Merge GDB 7.5.1

gdb/mips-tdep.c

 /* Target-dependent code for the MIPS architecture, for GDB, the GNU Debugger.
 
    Copyright (C) 1988-2012 Free Software Foundation, Inc.
 
    Contributed by Alessandro Forin(af@cs.cmu.edu) at CMU
    and by Per Bothner(bothner@cs.wisc.edu) at U.Wisconsin.
 
    This file is part of GDB.
 
    This program is free software; you can redistribute it and/or modify
@@ skipping 44 matching lines @@
 #include "target-descriptions.h"
 #include "dwarf2-frame.h"
 #include "user-regs.h"
 #include "valprint.h"
 #include "ax.h"
 
 static const struct objfile_data *mips_pdr_data;
 
 static struct type *mips_register_type (struct gdbarch *gdbarch, int regnum);
 
+static int mips32_instruction_has_delay_slot (struct gdbarch *, CORE_ADDR);
+static int micromips_instruction_has_delay_slot (struct gdbarch *, CORE_ADDR,
+                                                 int);
+static int mips16_instruction_has_delay_slot (struct gdbarch *, CORE_ADDR,
+                                              int);
+
 /* A useful bit in the CP0 status register (MIPS_PS_REGNUM).  */
 /* This bit is set if we are emulating 32-bit FPRs on a 64-bit chip.  */
 #define ST0_FR (1 << 26)
 
 /* The sizes of floating point registers.  */
 
 enum
 {
   MIPS_FPU_SINGLE_REGSIZE = 4,
   MIPS_FPU_DOUBLE_REGSIZE = 8
 };
 
 enum
 {
   MIPS32_REGSIZE = 4,
   MIPS64_REGSIZE = 8
 };
 
 static const char *mips_abi_string;
 
-static const char *mips_abi_strings[] = {
+static const char *const mips_abi_strings[] = {
   "auto",
   "n32",
   "o32",
   "n64",
   "o64",
   "eabi32",
   "eabi64",
   NULL
 };
 
+/* For backwards compatibility we default to MIPS16.  This flag is
+   overridden as soon as unambiguous ELF file flags tell us the
+   compressed ISA encoding used.  */
+static const char mips_compression_mips16[] = "mips16";
+static const char mips_compression_micromips[] = "micromips";
+static const char *const mips_compression_strings[] =
+{
+  mips_compression_mips16,
+  mips_compression_micromips,
+  NULL
+};
+
+static const char *mips_compression_string = mips_compression_mips16;
+
 /* The standard register names, and all the valid aliases for them.  */
 struct register_alias
 {
   const char *name;
   int regnum;
 };
 
 /* Aliases for o32 and most other ABIs.  */
 const struct register_alias mips_o32_aliases[] = {
   { "ta0", 12 },
@@ skipping 66 matching lines @@
 {
   return gdbarch_tdep (gdbarch)->regnum;
 }
 
 static int
 mips_fpa0_regnum (struct gdbarch *gdbarch)
 {
   return mips_regnum (gdbarch)->fp0 + 12;
 }
 
+/* Return 1 if REGNUM refers to a floating-point general register, raw
+   or cooked.  Otherwise return 0.  */
+
+static int
+mips_float_register_p (struct gdbarch *gdbarch, int regnum)
+{
+  int rawnum = regnum % gdbarch_num_regs (gdbarch);
+
+  return (rawnum >= mips_regnum (gdbarch)->fp0
+          && rawnum < mips_regnum (gdbarch)->fp0 + 32);
+}
+
 #define MIPS_EABI(gdbarch) (gdbarch_tdep (gdbarch)->mips_abi \
                      == MIPS_ABI_EABI32 \
                    || gdbarch_tdep (gdbarch)->mips_abi == MIPS_ABI_EABI64)
 
 #define MIPS_LAST_FP_ARG_REGNUM(gdbarch) \
   (gdbarch_tdep (gdbarch)->mips_last_fp_arg_regnum)
 
 #define MIPS_LAST_ARG_REGNUM(gdbarch) \
   (gdbarch_tdep (gdbarch)->mips_last_arg_regnum)
 
 #define MIPS_FPU_TYPE(gdbarch) (gdbarch_tdep (gdbarch)->mips_fpu_type)
 
-/* MIPS16 function addresses are odd (bit 0 is set).  Here are some
-   functions to test, set, or clear bit 0 of addresses.  */
-
-static CORE_ADDR
-is_mips16_addr (CORE_ADDR addr)
-{
-  return ((addr) & 1);
-}
-
-static CORE_ADDR
-unmake_mips16_addr (CORE_ADDR addr)
-{
-  return ((addr) & ~(CORE_ADDR) 1);
-}
-
-static CORE_ADDR
-make_mips16_addr (CORE_ADDR addr)
-{
-  return ((addr) | (CORE_ADDR) 1);
-}
-
 /* Return the MIPS ABI associated with GDBARCH.  */
 enum mips_abi
 mips_abi (struct gdbarch *gdbarch)
 {
   return gdbarch_tdep (gdbarch)->mips_abi;
 }
 
 int
 mips_isa_regsize (struct gdbarch *gdbarch)
 {
@@ skipping 23 matching lines @@
     case MIPS_ABI_O64:
     case MIPS_ABI_EABI64:
       return 8;
     case MIPS_ABI_UNKNOWN:
     case MIPS_ABI_LAST:
     default:
       internal_error (__FILE__, __LINE__, _("bad switch"));
     }
 }
 
+/* MIPS16/microMIPS function addresses are odd (bit 0 is set).  Here
+   are some functions to handle addresses associated with compressed
+   code including but not limited to testing, setting, or clearing
+   bit 0 of such addresses.  */
+
+/* Return one iff compressed code is the MIPS16 instruction set.  */
+
+static int
+is_mips16_isa (struct gdbarch *gdbarch)
+{
+  return gdbarch_tdep (gdbarch)->mips_isa == ISA_MIPS16;
+}
+
+/* Return one iff compressed code is the microMIPS instruction set.  */
+
+static int
+is_micromips_isa (struct gdbarch *gdbarch)
+{
+  return gdbarch_tdep (gdbarch)->mips_isa == ISA_MICROMIPS;
+}
+
+/* Return one iff ADDR denotes compressed code.  */
+
+static int
+is_compact_addr (CORE_ADDR addr)
+{
+  return ((addr) & 1);
+}
+
+/* Return one iff ADDR denotes standard ISA code.  */
+
+static int
+is_mips_addr (CORE_ADDR addr)
+{
+  return !is_compact_addr (addr);
+}
+
+/* Return one iff ADDR denotes MIPS16 code.  */
+
+static int
+is_mips16_addr (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+  return is_compact_addr (addr) && is_mips16_isa (gdbarch);
+}
+
+/* Return one iff ADDR denotes microMIPS code.  */
+
+static int
+is_micromips_addr (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+  return is_compact_addr (addr) && is_micromips_isa (gdbarch);
+}
+
+/* Strip the ISA (compression) bit off from ADDR.  */
+
+static CORE_ADDR
+unmake_compact_addr (CORE_ADDR addr)
+{
+  return ((addr) & ~(CORE_ADDR) 1);
+}
+
+/* Add the ISA (compression) bit to ADDR.  */
+
+static CORE_ADDR
+make_compact_addr (CORE_ADDR addr)
+{
+  return ((addr) | (CORE_ADDR) 1);
+}
+
 /* Functions for setting and testing a bit in a minimal symbol that
-   marks it as 16-bit function.  The MSB of the minimal symbol's
-   "info" field is used for this purpose.
+   marks it as MIPS16 or microMIPS function.  The MSB of the minimal
+   symbol's "info" field is used for this purpose.
 
-   gdbarch_elf_make_msymbol_special tests whether an ELF symbol is "special",
-   i.e. refers to a 16-bit function, and sets a "special" bit in a
-   minimal symbol to mark it as a 16-bit function
+   gdbarch_elf_make_msymbol_special tests whether an ELF symbol is
+   "special", i.e. refers to a MIPS16 or microMIPS function, and sets
+   one of the "special" bits in a minimal symbol to mark it accordingly.
+   The test checks an ELF-private flag that is valid for true function
+   symbols only; in particular synthetic symbols such as for PLT stubs
+   have no ELF-private part at all.
 
-   MSYMBOL_IS_SPECIAL   tests the "special" bit in a minimal symbol  */
+   msymbol_is_mips16 and msymbol_is_micromips test the "special" bit
+   in a minimal symbol.  */
 
 static void
 mips_elf_make_msymbol_special (asymbol * sym, struct minimal_symbol *msym)
 {
-  if (((elf_symbol_type *) (sym))->internal_elf_sym.st_other == STO_MIPS16)
-    {
-      MSYMBOL_TARGET_FLAG_1 (msym) = 1;
-    }
+  elf_symbol_type *elfsym = (elf_symbol_type *) sym;
+
+  if ((sym->flags & BSF_SYNTHETIC) != 0)
+    return;
+
+  if (ELF_ST_IS_MICROMIPS (elfsym->internal_elf_sym.st_other))
+    MSYMBOL_TARGET_FLAG_2 (msym) = 1;
+  else if (ELF_ST_IS_MIPS16 (elfsym->internal_elf_sym.st_other))
+    MSYMBOL_TARGET_FLAG_1 (msym) = 1;
 }
 
+/* Return one iff MSYM refers to standard ISA code.  */
+
 static int
-msymbol_is_special (struct minimal_symbol *msym)
+msymbol_is_mips (struct minimal_symbol *msym)
+{
+  return !(MSYMBOL_TARGET_FLAG_1 (msym) | MSYMBOL_TARGET_FLAG_2 (msym));
+}
+
+/* Return one iff MSYM refers to MIPS16 code.  */
+
+static int
+msymbol_is_mips16 (struct minimal_symbol *msym)
 {
   return MSYMBOL_TARGET_FLAG_1 (msym);
 }
 
+/* Return one iff MSYM refers to microMIPS code.  */
+
+static int
+msymbol_is_micromips (struct minimal_symbol *msym)
+{
+  return MSYMBOL_TARGET_FLAG_2 (msym);
+}
+
 /* XFER a value from the big/little/left end of the register.
    Depending on the size of the value it might occupy the entire
    register or just part of it.  Make an allowance for this, aligning
    things accordingly.  */
 
 static void
 mips_xfer_register (struct gdbarch *gdbarch, struct regcache *regcache,
                     int reg_num, int length,
                     enum bfd_endian endian, gdb_byte *in,
                     const gdb_byte *out, int buf_offset)
@@ skipping 90 matching lines @@
 { NUM_MIPS_PROCESSOR_REGS = (90 - 32) };
 
 /* Generic MIPS.  */
 
 static const char *mips_generic_reg_names[NUM_MIPS_PROCESSOR_REGS] = {
   "sr", "lo", "hi", "bad", "cause", "pc",
   "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
   "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
   "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
   "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
-  "fsr", "fir", "" /*"fp" */ , "",
-  "", "", "", "", "", "", "", "",
-  "", "", "", "", "", "", "", "",
+  "fsr", "fir",
 };
 
 /* Names of IDT R3041 registers.  */
 
 static const char *mips_r3041_reg_names[] = {
   "sr", "lo", "hi", "bad", "cause", "pc",
   "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
   "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
   "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
   "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
   "fsr", "fir", "", /*"fp" */ "",
   "", "", "bus", "ccfg", "", "", "", "",
   "", "", "port", "cmp", "", "", "epc", "prid",
 };
 
 /* Names of tx39 registers.  */
 
 static const char *mips_tx39_reg_names[NUM_MIPS_PROCESSOR_REGS] = {
   "sr", "lo", "hi", "bad", "cause", "pc",
   "", "", "", "", "", "", "", "",
   "", "", "", "", "", "", "", "",
   "", "", "", "", "", "", "", "",
   "", "", "", "", "", "", "", "",
   "", "", "", "",
   "", "", "", "", "", "", "", "",
-  "", "", "config", "cache", "debug", "depc", "epc", ""
+  "", "", "config", "cache", "debug", "depc", "epc",
 };
 
 /* Names of IRIX registers.  */
 static const char *mips_irix_reg_names[NUM_MIPS_PROCESSOR_REGS] = {
   "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
   "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
   "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
   "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
   "pc", "cause", "bad", "hi", "lo", "fsr", "fir"
 };
 
+/* Names of registers with Linux kernels.  */
+static const char *mips_linux_reg_names[NUM_MIPS_PROCESSOR_REGS] = {
+  "sr", "lo", "hi", "bad", "cause", "pc",
+  "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7",
+  "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15",
+  "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23",
+  "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31",
+  "fsr", "fir"
+};
+
 
 /* Return the name of the register corresponding to REGNO.  */
 static const char *
 mips_register_name (struct gdbarch *gdbarch, int regno)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   /* GPR names for all ABIs other than n32/n64.  */
   static char *mips_gpr_names[] = {
     "zero", "at", "v0", "v1", "a0", "a1", "a2", "a3",
     "t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7",
@@ skipping 34 matching lines @@
       if (abi == MIPS_ABI_N32 || abi == MIPS_ABI_N64)
         return mips_n32_n64_gpr_names[rawnum];
       else
         return mips_gpr_names[rawnum];
     }
   else if (tdesc_has_registers (gdbarch_target_desc (gdbarch)))
     return tdesc_register_name (gdbarch, rawnum);
   else if (32 <= rawnum && rawnum < gdbarch_num_regs (gdbarch))
     {
       gdb_assert (rawnum - 32 < NUM_MIPS_PROCESSOR_REGS);
-      return tdep->mips_processor_reg_names[rawnum - 32];
+      if (tdep->mips_processor_reg_names[rawnum - 32])
+        return tdep->mips_processor_reg_names[rawnum - 32];
+      return "";
     }
   else
     internal_error (__FILE__, __LINE__,
                     _("mips_register_name: bad register number %d"), rawnum);
 }
 
 /* Return the groups that a MIPS register can be categorised into.  */
 
 static int
 mips_register_reggroup_p (struct gdbarch *gdbarch, int regnum,
@@ skipping 158 matching lines @@
           ax_const_l (ax, 32);
           ax_simple (ax, aop_rsh_signed);
         }
     }
   else
     internal_error (__FILE__, __LINE__, _("bad register size"));
 
   return 0;
 }
 
-/* Table to translate MIPS16 register field to actual register number.  */
-static int mips16_to_32_reg[8] = { 16, 17, 2, 3, 4, 5, 6, 7 };
+/* Table to translate 3-bit register field to actual register number.  */
+static const signed char mips_reg3_to_reg[8] = { 16, 17, 2, 3, 4, 5, 6, 7 };
 
 /* Heuristic_proc_start may hunt through the text section for a long
    time across a 2400 baud serial line.  Allows the user to limit this
    search.  */
 
 static unsigned int heuristic_fence_post = 0;
 
 /* Number of bytes of storage in the actual machine representation for
    register N.  NOTE: This defines the pseudo register type so need to
    rebuild the architecture vector.  */
@@ skipping 21 matching lines @@
 /* This predicate tests for the case of an 8 byte floating point
    value that is being transferred to or from a pair of floating point
    registers each of which are (or are considered to be) only 4 bytes
    wide.  */
 static int
 mips_convert_register_float_case_p (struct gdbarch *gdbarch, int regnum,
                                     struct type *type)
 {
   return (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG
           && register_size (gdbarch, regnum) == 4
-          && (regnum % gdbarch_num_regs (gdbarch))
-                >= mips_regnum (gdbarch)->fp0
-          && (regnum % gdbarch_num_regs (gdbarch))
-                < mips_regnum (gdbarch)->fp0 + 32
+          && mips_float_register_p (gdbarch, regnum)
           && TYPE_CODE (type) == TYPE_CODE_FLT && TYPE_LENGTH (type) == 8);
 }
 
 /* This predicate tests for the case of a value of less than 8
    bytes in width that is being transfered to or from an 8 byte
    general purpose register.  */
 static int
 mips_convert_register_gpreg_case_p (struct gdbarch *gdbarch, int regnum,
                                     struct type *type)
 {
   int num_regs = gdbarch_num_regs (gdbarch);
 
   return (register_size (gdbarch, regnum) == 8
           && regnum % num_regs > 0 && regnum % num_regs < 32
           && TYPE_LENGTH (type) < 8);
 }
 
 static int
 mips_convert_register_p (struct gdbarch *gdbarch,
                          int regnum, struct type *type)
 {
-  return mips_convert_register_float_case_p (gdbarch, regnum, type)
-      || mips_convert_register_gpreg_case_p (gdbarch, regnum, type);
+  return (mips_convert_register_float_case_p (gdbarch, regnum, type)
+          || mips_convert_register_gpreg_case_p (gdbarch, regnum, type));
 }
 
 static int
 mips_register_to_value (struct frame_info *frame, int regnum,
                         struct type *type, gdb_byte *to,
                         int *optimizedp, int *unavailablep)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
 
   if (mips_convert_register_float_case_p (gdbarch, regnum, type))
@@ skipping 79 matching lines @@
     }
 }
 
 /* Return the GDB type object for the "standard" data type of data in
    register REG.  */
 
 static struct type *
 mips_register_type (struct gdbarch *gdbarch, int regnum)
 {
   gdb_assert (regnum >= 0 && regnum < 2 * gdbarch_num_regs (gdbarch));
-  if ((regnum % gdbarch_num_regs (gdbarch)) >= mips_regnum (gdbarch)->fp0
-      && (regnum % gdbarch_num_regs (gdbarch))
-         < mips_regnum (gdbarch)->fp0 + 32)
+  if (mips_float_register_p (gdbarch, regnum))
     {
       /* The floating-point registers raw, or cooked, always match
          mips_isa_regsize(), and also map 1:1, byte for byte.  */
       if (mips_isa_regsize (gdbarch) == 4)
         return builtin_type (gdbarch)->builtin_float;
       else
         return builtin_type (gdbarch)->builtin_double;
     }
   else if (regnum < gdbarch_num_regs (gdbarch))
     {
       /* The raw or ISA registers.  These are all sized according to
          the ISA regsize.  */
       if (mips_isa_regsize (gdbarch) == 4)
         return builtin_type (gdbarch)->builtin_int32;
       else
         return builtin_type (gdbarch)->builtin_int64;
     }
   else
     {
+      int rawnum = regnum - gdbarch_num_regs (gdbarch);
+
       /* The cooked or ABI registers.  These are sized according to
          the ABI (with a few complications).  */
-      if (regnum >= (gdbarch_num_regs (gdbarch)
-                     + mips_regnum (gdbarch)->fp_control_status)
-          && regnum <= gdbarch_num_regs (gdbarch) + MIPS_LAST_EMBED_REGNUM)
+      if (rawnum == mips_regnum (gdbarch)->fp_control_status
+          || rawnum == mips_regnum (gdbarch)->fp_implementation_revision)
+        return builtin_type (gdbarch)->builtin_int32;
+      else if (gdbarch_osabi (gdbarch) != GDB_OSABI_IRIX
+               && gdbarch_osabi (gdbarch) != GDB_OSABI_LINUX
+               && rawnum >= MIPS_FIRST_EMBED_REGNUM
+               && rawnum <= MIPS_LAST_EMBED_REGNUM)
         /* The pseudo/cooked view of the embedded registers is always
            32-bit.  The raw view is handled below.  */
         return builtin_type (gdbarch)->builtin_int32;
       else if (gdbarch_tdep (gdbarch)->mips64_transfers_32bit_regs_p)
         /* The target, while possibly using a 64-bit register buffer,
            is only transfering 32-bits of each integer register.
            Reflect this in the cooked/pseudo (ABI) register value.  */
         return builtin_type (gdbarch)->builtin_int32;
       else if (mips_abi_regsize (gdbarch) == 4)
         /* The ABI is restricted to 32-bit registers (the ISA could be
            32- or 64-bit).  */
         return builtin_type (gdbarch)->builtin_int32;
       else
         /* 64-bit ABI.  */
         return builtin_type (gdbarch)->builtin_int64;
     }
 }
 
 /* Return the GDB type for the pseudo register REGNUM, which is the
    ABI-level view.  This function is only called if there is a target
    description which includes registers, so we know precisely the
    types of hardware registers.  */
 
 static struct type *
 mips_pseudo_register_type (struct gdbarch *gdbarch, int regnum)
 {
   const int num_regs = gdbarch_num_regs (gdbarch);
-  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   int rawnum = regnum % num_regs;
   struct type *rawtype;
 
   gdb_assert (regnum >= num_regs && regnum < 2 * num_regs);
 
   /* Absent registers are still absent.  */
   rawtype = gdbarch_register_type (gdbarch, rawnum);
   if (TYPE_LENGTH (rawtype) == 0)
     return rawtype;
 
-  if (rawnum >= MIPS_EMBED_FP0_REGNUM && rawnum < MIPS_EMBED_FP0_REGNUM + 32)
+  if (mips_float_register_p (gdbarch, rawnum))
     /* Present the floating point registers however the hardware did;
        do not try to convert between FPU layouts.  */
     return rawtype;
 
-  if (rawnum >= MIPS_EMBED_FP0_REGNUM + 32 && rawnum <= MIPS_LAST_EMBED_REGNUM)
+  /* Use pointer types for registers if we can.  For n32 we can not,
+     since we do not have a 64-bit pointer type.  */
+  if (mips_abi_regsize (gdbarch)
+      == TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr))
+    {
+      if (rawnum == MIPS_SP_REGNUM
+          || rawnum == mips_regnum (gdbarch)->badvaddr)
+        return builtin_type (gdbarch)->builtin_data_ptr;
+      else if (rawnum == mips_regnum (gdbarch)->pc)
+        return builtin_type (gdbarch)->builtin_func_ptr;
+    }
+
+  if (mips_abi_regsize (gdbarch) == 4 && TYPE_LENGTH (rawtype) == 8
+      && ((rawnum >= MIPS_ZERO_REGNUM && rawnum <= MIPS_PS_REGNUM)
+          || rawnum == mips_regnum (gdbarch)->lo
+          || rawnum == mips_regnum (gdbarch)->hi
+          || rawnum == mips_regnum (gdbarch)->badvaddr
+          || rawnum == mips_regnum (gdbarch)->cause
+          || rawnum == mips_regnum (gdbarch)->pc
+          || (mips_regnum (gdbarch)->dspacc != -1
+              && rawnum >= mips_regnum (gdbarch)->dspacc
+              && rawnum < mips_regnum (gdbarch)->dspacc + 6)))
+    return builtin_type (gdbarch)->builtin_int32;
+
+  if (gdbarch_osabi (gdbarch) != GDB_OSABI_IRIX
+      && gdbarch_osabi (gdbarch) != GDB_OSABI_LINUX
+      && rawnum >= MIPS_EMBED_FP0_REGNUM + 32
+      && rawnum <= MIPS_LAST_EMBED_REGNUM)
     {
       /* The pseudo/cooked view of embedded registers is always
          32-bit, even if the target transfers 64-bit values for them.
          New targets relying on XML descriptions should only transfer
          the necessary 32 bits, but older versions of GDB expected 64,
          so allow the target to provide 64 bits without interfering
          with the displayed type.  */
       return builtin_type (gdbarch)->builtin_int32;
     }
 
-  /* Use pointer types for registers if we can.  For n32 we can not,
-     since we do not have a 64-bit pointer type.  */
-  if (mips_abi_regsize (gdbarch)
-      == TYPE_LENGTH (builtin_type (gdbarch)->builtin_data_ptr))
-    {
-      if (rawnum == MIPS_SP_REGNUM || rawnum == MIPS_EMBED_BADVADDR_REGNUM)
-        return builtin_type (gdbarch)->builtin_data_ptr;
-      else if (rawnum == MIPS_EMBED_PC_REGNUM)
-        return builtin_type (gdbarch)->builtin_func_ptr;
-    }
-
-  if (mips_abi_regsize (gdbarch) == 4 && TYPE_LENGTH (rawtype) == 8
-      && rawnum >= MIPS_ZERO_REGNUM && rawnum <= MIPS_EMBED_PC_REGNUM)
-    return builtin_type (gdbarch)->builtin_int32;
-
   /* For all other registers, pass through the hardware type.  */
   return rawtype;
 }
 
 /* Should the upper word of 64-bit addresses be zeroed?  */
 enum auto_boolean mask_address_var = AUTO_BOOLEAN_AUTO;
 
 static int
 mips_mask_address_p (struct gdbarch_tdep *tdep)
 {
@@ skipping 32 matching lines @@
       printf_filtered
         ("The 32 bit address mask is set automatically.  Currently %s\n",
          mips_mask_address_p (tdep) ? "enabled" : "disabled");
       break;
     default:
       internal_error (__FILE__, __LINE__, _("show_mask_address: bad switch"));
       break;
     }
 }
 
+/* Tell if the program counter value in MEMADDR is in a standard ISA
+   function.  */
+
+int
+mips_pc_is_mips (CORE_ADDR memaddr)
+{
+  struct minimal_symbol *sym;
+
+  /* Flags indicating that this is a MIPS16 or microMIPS function is
+     stored by elfread.c in the high bit of the info field.  Use this
+     to decide if the function is standard MIPS.  Otherwise if bit 0
+     of the address is clear, then this is a standard MIPS function.  */
+  sym = lookup_minimal_symbol_by_pc (memaddr);
+  if (sym)
+    return msymbol_is_mips (sym);
+  else
+    return is_mips_addr (memaddr);
+}
+
 /* Tell if the program counter value in MEMADDR is in a MIPS16 function.  */
 
 int
-mips_pc_is_mips16 (CORE_ADDR memaddr)
+mips_pc_is_mips16 (struct gdbarch *gdbarch, CORE_ADDR memaddr)
 {
   struct minimal_symbol *sym;
 
   /* A flag indicating that this is a MIPS16 function is stored by
      elfread.c in the high bit of the info field.  Use this to decide
-     if the function is MIPS16 or normal MIPS.  Otherwise if bit 0 of
-     the address is set, assume this is a MIPS16 address.  */
+     if the function is MIPS16.  Otherwise if bit 0 of the address is
+     set, then ELF file flags will tell if this is a MIPS16 function.  */
   sym = lookup_minimal_symbol_by_pc (memaddr);
   if (sym)
-    return msymbol_is_special (sym);
+    return msymbol_is_mips16 (sym);
   else
-    return is_mips16_addr (memaddr);
+    return is_mips16_addr (gdbarch, memaddr);
+}
+
+/* Tell if the program counter value in MEMADDR is in a microMIPS function.  */
+
+int
+mips_pc_is_micromips (struct gdbarch *gdbarch, CORE_ADDR memaddr)
+{
+  struct minimal_symbol *sym;
+
+  /* A flag indicating that this is a microMIPS function is stored by
+     elfread.c in the high bit of the info field.  Use this to decide
+     if the function is microMIPS.  Otherwise if bit 0 of the address
+     is set, then ELF file flags will tell if this is a microMIPS
+     function.  */
+  sym = lookup_minimal_symbol_by_pc (memaddr);
+  if (sym)
+    return msymbol_is_micromips (sym);
+  else
+    return is_micromips_addr (gdbarch, memaddr);
+}
+
+/* Tell the ISA type of the function the program counter value in MEMADDR
+   is in.  */
+
+static enum mips_isa
+mips_pc_isa (struct gdbarch *gdbarch, CORE_ADDR memaddr)
+{
+  struct minimal_symbol *sym;
+
+  /* A flag indicating that this is a MIPS16 or a microMIPS function
+     is stored by elfread.c in the high bit of the info field.  Use
+     this to decide if the function is MIPS16 or microMIPS or normal
+     MIPS.  Otherwise if bit 0 of the address is set, then ELF file
+     flags will tell if this is a MIPS16 or a microMIPS function.  */
+  sym = lookup_minimal_symbol_by_pc (memaddr);
+  if (sym)
+    {
+      if (msymbol_is_micromips (sym))
+        return ISA_MICROMIPS;
+      else if (msymbol_is_mips16 (sym))
+        return ISA_MIPS16;
+      else
+        return ISA_MIPS;
+    }
+  else
+    {
+      if (is_mips_addr (memaddr))
+        return ISA_MIPS;
+      else if (is_micromips_addr (gdbarch, memaddr))
+        return ISA_MICROMIPS;
+      else
+        return ISA_MIPS16;
+    }
+}
+
+/* Various MIPS16 thunk (aka stub or trampoline) names.  */
+
+static const char mips_str_mips16_call_stub[] = "__mips16_call_stub_";
+static const char mips_str_mips16_ret_stub[] = "__mips16_ret_";
+static const char mips_str_call_fp_stub[] = "__call_stub_fp_";
+static const char mips_str_call_stub[] = "__call_stub_";
+static const char mips_str_fn_stub[] = "__fn_stub_";
+
+/* This is used as a PIC thunk prefix.  */
+
+static const char mips_str_pic[] = ".pic.";
+
+/* Return non-zero if the PC is inside a call thunk (aka stub or
+   trampoline) that should be treated as a temporary frame.  */
+
+static int
+mips_in_frame_stub (CORE_ADDR pc)
+{
+  CORE_ADDR start_addr;
+  const char *name;
+
+  /* Find the starting address of the function containing the PC.  */
+  if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0)
+    return 0;
+
+  /* If the PC is in __mips16_call_stub_*, this is a call/return stub.  */
+  if (strncmp (name, mips_str_mips16_call_stub,
+               strlen (mips_str_mips16_call_stub)) == 0)
+    return 1;
+  /* If the PC is in __call_stub_*, this is a call/return or a call stub.  */
+  if (strncmp (name, mips_str_call_stub, strlen (mips_str_call_stub)) == 0)
+    return 1;
+  /* If the PC is in __fn_stub_*, this is a call stub.  */
+  if (strncmp (name, mips_str_fn_stub, strlen (mips_str_fn_stub)) == 0)
+    return 1;
+
+  return 0;                     /* Not a stub.  */
 }
 
 /* MIPS believes that the PC has a sign extended value.  Perhaps the
    all registers should be sign extended for simplicity?  */
 
 static CORE_ADDR
 mips_read_pc (struct regcache *regcache)
 {
+  int regnum = gdbarch_pc_regnum (get_regcache_arch (regcache));
   ULONGEST pc;
-  int regnum = mips_regnum (get_regcache_arch (regcache))->pc;
+
   regcache_cooked_read_signed (regcache, regnum, &pc);
-  if (is_mips16_addr (pc))
-    pc = unmake_mips16_addr (pc);
+  if (is_compact_addr (pc))
+    pc = unmake_compact_addr (pc);
   return pc;
 }
 
 static CORE_ADDR
 mips_unwind_pc (struct gdbarch *gdbarch, struct frame_info *next_frame)
 {
-  ULONGEST pc;
+  CORE_ADDR pc;
 
-  pc = frame_unwind_register_signed
-         (next_frame, gdbarch_num_regs (gdbarch) + mips_regnum (gdbarch)->pc);
-  if (is_mips16_addr (pc))
-    pc = unmake_mips16_addr (pc);
+  pc = frame_unwind_register_signed (next_frame, gdbarch_pc_regnum (gdbarch));
+  if (is_compact_addr (pc))
+    pc = unmake_compact_addr (pc);
+  /* macro/2012-04-20: This hack skips over MIPS16 call thunks as
+     intermediate frames.  In this case we can get the caller's address
+     from $ra, or if $ra contains an address within a thunk as well, then
+     it must be in the return path of __mips16_call_stub_{s,d}{f,c}_{0..10}
+     and thus the caller's address is in $s2.  */
+  if (frame_relative_level (next_frame) >= 0 && mips_in_frame_stub (pc))
+    {
+      pc = frame_unwind_register_signed
+             (next_frame, gdbarch_num_regs (gdbarch) + MIPS_RA_REGNUM);
+      if (is_compact_addr (pc))
+        pc = unmake_compact_addr (pc);
+      if (mips_in_frame_stub (pc))
+        {
+          pc = frame_unwind_register_signed
+                 (next_frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM);
+          if (is_compact_addr (pc))
+            pc = unmake_compact_addr (pc);
+        }
+    }
   return pc;
 }
 
 static CORE_ADDR
 mips_unwind_sp (struct gdbarch *gdbarch, struct frame_info *next_frame)
 {
   return frame_unwind_register_signed
            (next_frame, gdbarch_num_regs (gdbarch) + MIPS_SP_REGNUM);
 }
 
 /* Assuming THIS_FRAME is a dummy, return the frame ID of that
    dummy frame.  The frame ID's base needs to match the TOS value
    saved by save_dummy_frame_tos(), and the PC match the dummy frame's
    breakpoint.  */
 
 static struct frame_id
 mips_dummy_id (struct gdbarch *gdbarch, struct frame_info *this_frame)
 {
   return frame_id_build
            (get_frame_register_signed (this_frame,
                                        gdbarch_num_regs (gdbarch)
                                        + MIPS_SP_REGNUM),
             get_frame_pc (this_frame));
 }
 
-static void
+/* Implement the "write_pc" gdbarch method.  */
+
+void
 mips_write_pc (struct regcache *regcache, CORE_ADDR pc)
 {
-  int regnum = mips_regnum (get_regcache_arch (regcache))->pc;
-  if (mips_pc_is_mips16 (pc))
-    regcache_cooked_write_unsigned (regcache, regnum, make_mips16_addr (pc));
+  int regnum = gdbarch_pc_regnum (get_regcache_arch (regcache));
+
+  if (mips_pc_is_mips (pc))
+    regcache_cooked_write_unsigned (regcache, regnum, pc);
   else
-    regcache_cooked_write_unsigned (regcache, regnum, pc);
+    regcache_cooked_write_unsigned (regcache, regnum, make_compact_addr (pc));
 }
 
-/* Fetch and return instruction from the specified location.  If the PC
-   is odd, assume it's a MIPS16 instruction; otherwise MIPS32.  */
+/* Fetch and return instruction from the specified location.  Handle
+   MIPS16/microMIPS as appropriate.  */
 
 static ULONGEST
-mips_fetch_instruction (struct gdbarch *gdbarch, CORE_ADDR addr)
+mips_fetch_instruction (struct gdbarch *gdbarch,
+                        enum mips_isa isa, CORE_ADDR addr, int *statusp)
 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   gdb_byte buf[MIPS_INSN32_SIZE];
   int instlen;
   int status;
 
-  if (mips_pc_is_mips16 (addr))
+  switch (isa)
     {
+    case ISA_MICROMIPS:
+    case ISA_MIPS16:
       instlen = MIPS_INSN16_SIZE;
-      addr = unmake_mips16_addr (addr);
+      addr = unmake_compact_addr (addr);
+      break;
+    case ISA_MIPS:
+      instlen = MIPS_INSN32_SIZE;
+      break;
+    default:
+      internal_error (__FILE__, __LINE__, _("invalid ISA"));
+      break;
     }
-  else
-    instlen = MIPS_INSN32_SIZE;
   status = target_read_memory (addr, buf, instlen);
+  if (statusp != NULL)
+    *statusp = status;
   if (status)
-    memory_error (status, addr);
+    {
+      if (statusp == NULL)
+        memory_error (status, addr);
+      return 0;
+    }
   return extract_unsigned_integer (buf, instlen, byte_order);
 }
 
 /* These are the fields of 32 bit mips instructions.  */
 #define mips32_op(x) (x >> 26)
 #define itype_op(x) (x >> 26)
 #define itype_rs(x) ((x >> 21) & 0x1f)
 #define itype_rt(x) ((x >> 16) & 0x1f)
 #define itype_immediate(x) (x & 0xffff)
 
 #define jtype_op(x) (x >> 26)
 #define jtype_target(x) (x & 0x03ffffff)
 
 #define rtype_op(x) (x >> 26)
 #define rtype_rs(x) ((x >> 21) & 0x1f)
 #define rtype_rt(x) ((x >> 16) & 0x1f)
 #define rtype_rd(x) ((x >> 11) & 0x1f)
 #define rtype_shamt(x) ((x >> 6) & 0x1f)
 #define rtype_funct(x) (x & 0x3f)
 
+/* MicroMIPS instruction fields.  */
+#define micromips_op(x) ((x) >> 10)
+
+/* 16-bit/32-bit-high-part instruction formats, B and S refer to the lowest
+   bit and the size respectively of the field extracted.  */
+#define b0s4_imm(x) ((x) & 0xf)
+#define b0s5_imm(x) ((x) & 0x1f)
+#define b0s5_reg(x) ((x) & 0x1f)
+#define b0s7_imm(x) ((x) & 0x7f)
+#define b0s10_imm(x) ((x) & 0x3ff)
+#define b1s4_imm(x) (((x) >> 1) & 0xf)
+#define b1s9_imm(x) (((x) >> 1) & 0x1ff)
+#define b2s3_cc(x) (((x) >> 2) & 0x7)
+#define b4s2_regl(x) (((x) >> 4) & 0x3)
+#define b5s5_op(x) (((x) >> 5) & 0x1f)
+#define b5s5_reg(x) (((x) >> 5) & 0x1f)
+#define b6s4_op(x) (((x) >> 6) & 0xf)
+#define b7s3_reg(x) (((x) >> 7) & 0x7)
+
+/* 32-bit instruction formats, B and S refer to the lowest bit and the size
+   respectively of the field extracted.  */
+#define b0s6_op(x) ((x) & 0x3f)
+#define b0s11_op(x) ((x) & 0x7ff)
+#define b0s12_imm(x) ((x) & 0xfff)
+#define b0s16_imm(x) ((x) & 0xffff)
+#define b0s26_imm(x) ((x) & 0x3ffffff)
+#define b6s10_ext(x) (((x) >> 6) & 0x3ff)
+#define b11s5_reg(x) (((x) >> 11) & 0x1f)
+#define b12s4_op(x) (((x) >> 12) & 0xf)
+
+/* Return the size in bytes of the instruction INSN encoded in the ISA
+   instruction set.  */
+
+static int
+mips_insn_size (enum mips_isa isa, ULONGEST insn)
+{
+  switch (isa)
+    {
+    case ISA_MICROMIPS:
+      if (micromips_op (insn) == 0x1f)
+        return 3 * MIPS_INSN16_SIZE;
+      else if (((micromips_op (insn) & 0x4) == 0x4)
+               || ((micromips_op (insn) & 0x7) == 0x0))
+        return 2 * MIPS_INSN16_SIZE;
+      else
+        return MIPS_INSN16_SIZE;
+    case ISA_MIPS16:
+      if ((insn & 0xf800) == 0xf000)
+        return 2 * MIPS_INSN16_SIZE;
+      else
+        return MIPS_INSN16_SIZE;
+    case ISA_MIPS:
+        return MIPS_INSN32_SIZE;
+    }
+  internal_error (__FILE__, __LINE__, _("invalid ISA"));
+}
+
 static LONGEST
 mips32_relative_offset (ULONGEST inst)
 {
   return ((itype_immediate (inst) ^ 0x8000) - 0x8000) << 2;
 }
 
+/* Determine the address of the next instruction executed after the INST
+   floating condition branch instruction at PC.  COUNT specifies the
+   number of the floating condition bits tested by the branch.  */
+
+static CORE_ADDR
+mips32_bc1_pc (struct gdbarch *gdbarch, struct frame_info *frame,
+               ULONGEST inst, CORE_ADDR pc, int count)
+{
+  int fcsr = mips_regnum (gdbarch)->fp_control_status;
+  int cnum = (itype_rt (inst) >> 2) & (count - 1);
+  int tf = itype_rt (inst) & 1;
+  int mask = (1 << count) - 1;
+  ULONGEST fcs;
+  int cond;
+
+  if (fcsr == -1)
+    /* No way to handle; it'll most likely trap anyway.  */
+    return pc;
+
+  fcs = get_frame_register_unsigned (frame, fcsr);
+  cond = ((fcs >> 24) & 0xfe) | ((fcs >> 23) & 0x01);
+
+  if (((cond >> cnum) & mask) != mask * !tf)
+    pc += mips32_relative_offset (inst);
+  else
+    pc += 4;
+
+  return pc;
+}
+
 /* Determine where to set a single step breakpoint while considering
    branch prediction.  */
 static CORE_ADDR
 mips32_next_pc (struct frame_info *frame, CORE_ADDR pc)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
   unsigned long inst;
   int op;
-  inst = mips_fetch_instruction (gdbarch, pc);
+  inst = mips_fetch_instruction (gdbarch, ISA_MIPS, pc, NULL);
   if ((inst & 0xe0000000) != 0)         /* Not a special, jump or branch
                                            instruction.  */
     {
       if (itype_op (inst) >> 2 == 5)
         /* BEQL, BNEL, BLEZL, BGTZL: bits 0101xx */
         {
           op = (itype_op (inst) & 0x03);
           switch (op)
             {
             case 0:             /* BEQL */
               goto equal_branch;
             case 1:             /* BNEL */
               goto neq_branch;
             case 2:             /* BLEZL */
               goto less_branch;
             case 3:             /* BGTZL */
               goto greater_branch;
             default:
               pc += 4;
             }
         }
       else if (itype_op (inst) == 17 && itype_rs (inst) == 8)
         /* BC1F, BC1FL, BC1T, BC1TL: 010001 01000 */
+        pc = mips32_bc1_pc (gdbarch, frame, inst, pc + 4, 1);
+      else if (itype_op (inst) == 17 && itype_rs (inst) == 9
+               && (itype_rt (inst) & 2) == 0)
+        /* BC1ANY2F, BC1ANY2T: 010001 01001 xxx0x */
+        pc = mips32_bc1_pc (gdbarch, frame, inst, pc + 4, 2);
+      else if (itype_op (inst) == 17 && itype_rs (inst) == 10
+               && (itype_rt (inst) & 2) == 0)
+        /* BC1ANY4F, BC1ANY4T: 010001 01010 xxx0x */
+        pc = mips32_bc1_pc (gdbarch, frame, inst, pc + 4, 4);
+      else if (itype_op (inst) == 29)
+        /* JALX: 011101 */
+        /* The new PC will be alternate mode.  */
         {
-          int tf = itype_rt (inst) & 0x01;
-          int cnum = itype_rt (inst) >> 2;
-          int fcrcs =
-            get_frame_register_signed (frame,
-                                       mips_regnum (get_frame_arch (frame))->
-                                                fp_control_status);
-          int cond = ((fcrcs >> 24) & 0xfe) | ((fcrcs >> 23) & 0x01);
+          unsigned long reg;
 
-          if (((cond >> cnum) & 0x01) == tf)
-            pc += mips32_relative_offset (inst) + 4;
-          else
-            pc += 8;
+          reg = jtype_target (inst) << 2;
+          /* Add 1 to indicate 16-bit mode -- invert ISA mode.  */
+          pc = ((pc + 4) & ~(CORE_ADDR) 0x0fffffff) + reg + 1;
         }
       else
         pc += 4;                /* Not a branch, next instruction is easy.  */
     }
   else
     {                           /* This gets way messy.  */
 
       /* Further subdivide into SPECIAL, REGIMM and other.  */
       switch (op = itype_op (inst) & 0x07)      /* Extract bits 28,27,26.  */
         {
@@ skipping 39 matching lines @@
                 break;
               case 1:           /* BGEZ */
               case 3:           /* BGEZL */
               case 17:          /* BGEZAL */
               case 19:          /* BGEZALL */
                 if (get_frame_register_signed (frame, itype_rs (inst)) >= 0)
                   pc += mips32_relative_offset (inst) + 4;
                 else
                   pc += 8;      /* after the delay slot */
                 break;
+              case 0x1c:        /* BPOSGE32 */
+              case 0x1e:        /* BPOSGE64 */
+                pc += 4;
+                if (itype_rs (inst) == 0)
+                  {
+                    unsigned int pos = (op & 2) ? 64 : 32;
+                    int dspctl = mips_regnum (gdbarch)->dspctl;
+
+                    if (dspctl == -1)
+                      /* No way to handle; it'll most likely trap anyway.  */
+                      break;
+
+                    if ((get_frame_register_unsigned (frame,
+                                                      dspctl) & 0x7f) >= pos)
+                      pc += mips32_relative_offset (inst);
+                    else
+                      pc += 4;
+                  }
+                break;
                 /* All of the other instructions in the REGIMM category */
               default:
                 pc += 4;
               }
           }
           break;                /* end REGIMM */
         case 2:         /* J */
         case 3:         /* JAL */
           {
             unsigned long reg;
             reg = jtype_target (inst) << 2;
             /* Upper four bits get never changed...  */
             pc = reg + ((pc + 4) & ~(CORE_ADDR) 0x0fffffff);
           }
           break;
-          /* FIXME case JALX : */
-          {
-            unsigned long reg;
-            reg = jtype_target (inst) << 2;
-            pc = reg + ((pc + 4) & ~(CORE_ADDR) 0x0fffffff) + 1;  /* yes, +1 */
-            /* Add 1 to indicate 16 bit mode - Invert ISA mode */
-          }
-          break;                /* The new PC will be alternate mode */
         case 4:         /* BEQ, BEQL */
         equal_branch:
           if (get_frame_register_signed (frame, itype_rs (inst)) ==
               get_frame_register_signed (frame, itype_rt (inst)))
             pc += mips32_relative_offset (inst) + 4;
           else
             pc += 8;
           break;
         case 5:         /* BNE, BNEL */
         neq_branch:
@@ skipping 15 matching lines @@
           if (get_frame_register_signed (frame, itype_rs (inst)) > 0)
             pc += mips32_relative_offset (inst) + 4;
           else
             pc += 8;
           break;
         }                       /* switch */
     }                           /* else */
   return pc;
 }                               /* mips32_next_pc */
 
+/* Extract the 7-bit signed immediate offset from the microMIPS instruction
+   INSN.  */
+
+static LONGEST
+micromips_relative_offset7 (ULONGEST insn)
+{
+  return ((b0s7_imm (insn) ^ 0x40) - 0x40) << 1;
+}
+
+/* Extract the 10-bit signed immediate offset from the microMIPS instruction
+   INSN.  */
+
+static LONGEST
+micromips_relative_offset10 (ULONGEST insn)
+{
+  return ((b0s10_imm (insn) ^ 0x200) - 0x200) << 1;
+}
+
+/* Extract the 16-bit signed immediate offset from the microMIPS instruction
+   INSN.  */
+
+static LONGEST
+micromips_relative_offset16 (ULONGEST insn)
+{
+  return ((b0s16_imm (insn) ^ 0x8000) - 0x8000) << 1;
+}
+
+/* Return the size in bytes of the microMIPS instruction at the address PC.  */
+
+static int
+micromips_pc_insn_size (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+  ULONGEST insn;
+
+  insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, NULL);
+  return mips_insn_size (ISA_MICROMIPS, insn);
+}
+
+/* Calculate the address of the next microMIPS instruction to execute
+   after the INSN coprocessor 1 conditional branch instruction at the
+   address PC.  COUNT denotes the number of coprocessor condition bits
+   examined by the branch.  */
+
+static CORE_ADDR
+micromips_bc1_pc (struct gdbarch *gdbarch, struct frame_info *frame,
+                  ULONGEST insn, CORE_ADDR pc, int count)
+{
+  int fcsr = mips_regnum (gdbarch)->fp_control_status;
+  int cnum = b2s3_cc (insn >> 16) & (count - 1);
+  int tf = b5s5_op (insn >> 16) & 1;
+  int mask = (1 << count) - 1;
+  ULONGEST fcs;
+  int cond;
+
+  if (fcsr == -1)
+    /* No way to handle; it'll most likely trap anyway.  */
+    return pc;
+
+  fcs = get_frame_register_unsigned (frame, fcsr);
+  cond = ((fcs >> 24) & 0xfe) | ((fcs >> 23) & 0x01);
+
+  if (((cond >> cnum) & mask) != mask * !tf)
+    pc += micromips_relative_offset16 (insn);
+  else
+    pc += micromips_pc_insn_size (gdbarch, pc);
+
+  return pc;
+}
+
+/* Calculate the address of the next microMIPS instruction to execute
+   after the instruction at the address PC.  */
+
+static CORE_ADDR
+micromips_next_pc (struct frame_info *frame, CORE_ADDR pc)
+{
+  struct gdbarch *gdbarch = get_frame_arch (frame);
+  ULONGEST insn;
+
+  insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, NULL);
+  pc += MIPS_INSN16_SIZE;
+  switch (mips_insn_size (ISA_MICROMIPS, insn))
+    {
+    /* 48-bit instructions.  */
+    case 3 * MIPS_INSN16_SIZE: /* POOL48A: bits 011111 */
+      /* No branch or jump instructions in this category.  */
+      pc += 2 * MIPS_INSN16_SIZE;
+      break;
+
+    /* 32-bit instructions.  */
+    case 2 * MIPS_INSN16_SIZE:
+      insn <<= 16;
+      insn |= mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, NULL);
+      pc += MIPS_INSN16_SIZE;
+      switch (micromips_op (insn >> 16))
+        {
+        case 0x00: /* POOL32A: bits 000000 */
+          if (b0s6_op (insn) == 0x3c
+                                /* POOL32Axf: bits 000000 ... 111100 */
+              && (b6s10_ext (insn) & 0x2bf) == 0x3c)
+                                /* JALR, JALR.HB: 000000 000x111100 111100 */
+                                /* JALRS, JALRS.HB: 000000 010x111100 111100 */
+            pc = get_frame_register_signed (frame, b0s5_reg (insn >> 16));
+          break;
+
+        case 0x10: /* POOL32I: bits 010000 */
+          switch (b5s5_op (insn >> 16))
+            {
+            case 0x00: /* BLTZ: bits 010000 00000 */
+            case 0x01: /* BLTZAL: bits 010000 00001 */
+            case 0x11: /* BLTZALS: bits 010000 10001 */
+              if (get_frame_register_signed (frame,
+                                             b0s5_reg (insn >> 16)) < 0)
+                pc += micromips_relative_offset16 (insn);
+              else
+                pc += micromips_pc_insn_size (gdbarch, pc);
+              break;
+
+            case 0x02: /* BGEZ: bits 010000 00010 */
+            case 0x03: /* BGEZAL: bits 010000 00011 */
+            case 0x13: /* BGEZALS: bits 010000 10011 */
+              if (get_frame_register_signed (frame,
+                                             b0s5_reg (insn >> 16)) >= 0)
+                pc += micromips_relative_offset16 (insn);
+              else
+                pc += micromips_pc_insn_size (gdbarch, pc);
+              break;
+
+            case 0x04: /* BLEZ: bits 010000 00100 */
+              if (get_frame_register_signed (frame,
+                                             b0s5_reg (insn >> 16)) <= 0)
+                pc += micromips_relative_offset16 (insn);
+              else
+                pc += micromips_pc_insn_size (gdbarch, pc);
+              break;
+
+            case 0x05: /* BNEZC: bits 010000 00101 */
+              if (get_frame_register_signed (frame,
+                                             b0s5_reg (insn >> 16)) != 0)
+                pc += micromips_relative_offset16 (insn);
+              break;
+
+            case 0x06: /* BGTZ: bits 010000 00110 */
+              if (get_frame_register_signed (frame,
+                                             b0s5_reg (insn >> 16)) > 0)
+                pc += micromips_relative_offset16 (insn);
+              else
+                pc += micromips_pc_insn_size (gdbarch, pc);
+              break;
+
+            case 0x07: /* BEQZC: bits 010000 00111 */
+              if (get_frame_register_signed (frame,
+                                             b0s5_reg (insn >> 16)) == 0)
+                pc += micromips_relative_offset16 (insn);
+              break;
+
+            case 0x14: /* BC2F: bits 010000 10100 xxx00 */
+            case 0x15: /* BC2T: bits 010000 10101 xxx00 */
+              if (((insn >> 16) & 0x3) == 0x0)
+                /* BC2F, BC2T: don't know how to handle these.  */
+                break;
+              break;
+
+            case 0x1a: /* BPOSGE64: bits 010000 11010 */
+            case 0x1b: /* BPOSGE32: bits 010000 11011 */
+              {
+                unsigned int pos = (b5s5_op (insn >> 16) & 1) ? 32 : 64;
+                int dspctl = mips_regnum (gdbarch)->dspctl;
+
+                if (dspctl == -1)
+                  /* No way to handle; it'll most likely trap anyway.  */
+                  break;
+
+                if ((get_frame_register_unsigned (frame,
+                                                  dspctl) & 0x7f) >= pos)
+                  pc += micromips_relative_offset16 (insn);
+                else
+                  pc += micromips_pc_insn_size (gdbarch, pc);
+              }
+              break;
+
+            case 0x1c: /* BC1F: bits 010000 11100 xxx00 */
+                       /* BC1ANY2F: bits 010000 11100 xxx01 */
+            case 0x1d: /* BC1T: bits 010000 11101 xxx00 */
+                       /* BC1ANY2T: bits 010000 11101 xxx01 */
+              if (((insn >> 16) & 0x2) == 0x0)
+                pc = micromips_bc1_pc (gdbarch, frame, insn, pc,
+                                       ((insn >> 16) & 0x1) + 1);
+              break;
+
+            case 0x1e: /* BC1ANY4F: bits 010000 11110 xxx01 */
+            case 0x1f: /* BC1ANY4T: bits 010000 11111 xxx01 */
+              if (((insn >> 16) & 0x3) == 0x1)
+                pc = micromips_bc1_pc (gdbarch, frame, insn, pc, 4);
+              break;
+            }
+          break;
+
+        case 0x1d: /* JALS: bits 011101 */
+        case 0x35: /* J: bits 110101 */
+        case 0x3d: /* JAL: bits 111101 */
+            pc = ((pc | 0x7fffffe) ^ 0x7fffffe) | (b0s26_imm (insn) << 1);
+          break;
+
+        case 0x25: /* BEQ: bits 100101 */
+            if (get_frame_register_signed (frame, b0s5_reg (insn >> 16))
+                == get_frame_register_signed (frame, b5s5_reg (insn >> 16)))
+              pc += micromips_relative_offset16 (insn);
+            else
+              pc += micromips_pc_insn_size (gdbarch, pc);
+          break;
+
+        case 0x2d: /* BNE: bits 101101 */
+            if (get_frame_register_signed (frame, b0s5_reg (insn >> 16))
+                != get_frame_register_signed (frame, b5s5_reg (insn >> 16)))
+              pc += micromips_relative_offset16 (insn);
+            else
+              pc += micromips_pc_insn_size (gdbarch, pc);
+          break;
+
+        case 0x3c: /* JALX: bits 111100 */
+            pc = ((pc | 0xfffffff) ^ 0xfffffff) | (b0s26_imm (insn) << 2);
+          break;
+        }
+      break;
+
+    /* 16-bit instructions.  */
+    case MIPS_INSN16_SIZE:
+      switch (micromips_op (insn))
+        {
+        case 0x11: /* POOL16C: bits 010001 */
+          if ((b5s5_op (insn) & 0x1c) == 0xc)
+            /* JR16, JRC, JALR16, JALRS16: 010001 011xx */
+            pc = get_frame_register_signed (frame, b0s5_reg (insn));
+          else if (b5s5_op (insn) == 0x18)
+            /* JRADDIUSP: bits 010001 11000 */
+            pc = get_frame_register_signed (frame, MIPS_RA_REGNUM);
+          break;
+
+        case 0x23: /* BEQZ16: bits 100011 */
+          {
+            int rs = mips_reg3_to_reg[b7s3_reg (insn)];
+
+            if (get_frame_register_signed (frame, rs) == 0)
+              pc += micromips_relative_offset7 (insn);
+            else
+              pc += micromips_pc_insn_size (gdbarch, pc);
+          }
+          break;
+
+        case 0x2b: /* BNEZ16: bits 101011 */
+          {
+            int rs = mips_reg3_to_reg[b7s3_reg (insn)];
+
+            if (get_frame_register_signed (frame, rs) != 0)
+              pc += micromips_relative_offset7 (insn);
+            else
+              pc += micromips_pc_insn_size (gdbarch, pc);
+          }
+          break;
+
+        case 0x33: /* B16: bits 110011 */
+          pc += micromips_relative_offset10 (insn);
+          break;
+        }
+      break;
+    }
+
+  return pc;
+}
+
 /* Decoding the next place to set a breakpoint is irregular for the
    mips 16 variant, but fortunately, there fewer instructions.  We have
    to cope ith extensions for 16 bit instructions and a pair of actual
    32 bit instructions.  We dont want to set a single step instruction
    on the extend instruction either.  */
 
 /* Lots of mips16 instruction formats */
 /* Predicting jumps requires itype,ritype,i8type
    and their extensions      extItype,extritype,extI8type.  */
 enum mips16_inst_fmts
@@ skipping 114 matching lines @@
         regx = (inst >> 8) & 0x07;                      /* i8 funct */
         regy = -1;
         break;
       }
     case jalxtype:
       {
         unsigned long value;
         unsigned int nexthalf;
         value = ((inst & 0x1f) << 5) | ((inst >> 5) & 0x1f);
         value = value << 16;
-        nexthalf = mips_fetch_instruction (gdbarch, pc + 2);  /* low bit
-                                                                 still set.  */
+        nexthalf = mips_fetch_instruction (gdbarch, ISA_MIPS16, pc + 2, NULL);
+                                                /* Low bit still set.  */
         value |= nexthalf;
         offset = value;
         regx = -1;
         regy = -1;
         break;
       }
     default:
       internal_error (__FILE__, __LINE__, _("bad switch"));
     }
   upk->offset = offset;
@@ skipping 11 matching lines @@
 static CORE_ADDR
 extended_mips16_next_pc (struct frame_info *frame, CORE_ADDR pc,
                          unsigned int extension, unsigned int insn)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
   int op = (insn >> 11);
   switch (op)
     {
     case 2:                     /* Branch */
       {
-        CORE_ADDR offset;
         struct upk_mips16 upk;
         unpack_mips16 (gdbarch, pc, extension, insn, itype, &upk);
         pc += (upk.offset << 1) + 2;
         break;
       }
     case 3:                     /* JAL , JALX - Watch out, these are 32 bit
                                    instructions.  */
       {
         struct upk_mips16 upk;
         unpack_mips16 (gdbarch, pc, extension, insn, jalxtype, &upk);
         pc = add_offset_16 (pc, upk.offset);
         if ((insn >> 10) & 0x01)        /* Exchange mode */
           pc = pc & ~0x01;      /* Clear low bit, indicate 32 bit mode.  */
         else
           pc |= 0x01;
         break;
       }
     case 4:                     /* beqz */
       {
         struct upk_mips16 upk;
         int reg;
         unpack_mips16 (gdbarch, pc, extension, insn, ritype, &upk);
-        reg = get_frame_register_signed (frame, mips16_to_32_reg[upk.regx]);
+        reg = get_frame_register_signed (frame, mips_reg3_to_reg[upk.regx]);
         if (reg == 0)
           pc += (upk.offset << 1) + 2;
         else
           pc += 2;
         break;
       }
     case 5:                     /* bnez */
       {
         struct upk_mips16 upk;
         int reg;
         unpack_mips16 (gdbarch, pc, extension, insn, ritype, &upk);
-        reg = get_frame_register_signed (frame, mips16_to_32_reg[upk.regx]);
+        reg = get_frame_register_signed (frame, mips_reg3_to_reg[upk.regx]);
         if (reg != 0)
           pc += (upk.offset << 1) + 2;
         else
           pc += 2;
         break;
       }
     case 12:                    /* I8 Formats btez btnez */
       {
         struct upk_mips16 upk;
         int reg;
@@ skipping 12 matching lines @@
       {
         struct upk_mips16 upk;
         /* upk.fmt = rrtype; */
         op = insn & 0x1f;
         if (op == 0)
           {
             int reg;
             upk.regx = (insn >> 8) & 0x07;
             upk.regy = (insn >> 5) & 0x07;
             if ((upk.regy & 1) == 0)
-              reg = mips16_to_32_reg[upk.regx];
+              reg = mips_reg3_to_reg[upk.regx];
             else
               reg = 31;         /* Function return instruction.  */
             pc = get_frame_register_signed (frame, reg);
           }
         else
           pc += 2;
         break;
       }
     case 30:
       /* This is an instruction extension.  Fetch the real instruction
@@ skipping 19 matching lines @@
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
   unsigned int insn = fetch_mips_16 (gdbarch, pc);
   return extended_mips16_next_pc (frame, pc, 0, insn);
 }
 
 /* The mips_next_pc function supports single_step when the remote
    target monitor or stub is not developed enough to do a single_step.
    It works by decoding the current instruction and predicting where a
    branch will go.  This isnt hard because all the data is available.
-   The MIPS32 and MIPS16 variants are quite different.  */
+   The MIPS32, MIPS16 and microMIPS variants are quite different.  */
 static CORE_ADDR
 mips_next_pc (struct frame_info *frame, CORE_ADDR pc)
 {
-  if (mips_pc_is_mips16 (pc))
+  struct gdbarch *gdbarch = get_frame_arch (frame);
+
+  if (mips_pc_is_mips16 (gdbarch, pc))
     return mips16_next_pc (frame, pc);
+  else if (mips_pc_is_micromips (gdbarch, pc))
+    return micromips_next_pc (frame, pc);
   else
     return mips32_next_pc (frame, pc);
 }
 
 struct mips_frame_cache
 {
   CORE_ADDR base;
   struct trad_frame_saved_reg *saved_regs;
 };
 
@@ skipping 96 matching lines @@
   if (limit_pc > start_pc + 200)
     limit_pc = start_pc + 200;
 
   for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSN16_SIZE)
     {
       /* Save the previous instruction.  If it's an EXTEND, we'll extract
          the immediate offset extension from it in mips16_get_imm.  */
       prev_inst = inst;
 
       /* Fetch and decode the instruction.  */
-      inst = (unsigned short) mips_fetch_instruction (gdbarch, cur_pc);
+      inst = (unsigned short) mips_fetch_instruction (gdbarch, ISA_MIPS16,
+                                                      cur_pc, NULL);
 
       /* Normally we ignore extend instructions.  However, if it is
          not followed by a valid prologue instruction, then this
          instruction is not part of the prologue either.  We must
          remember in this case to adjust the end_prologue_addr back
          over the extend.  */
       if ((inst & 0xf800) == 0xf000)    /* extend */
         {
           extend_bytes = MIPS_INSN16_SIZE;
           continue;
@@ skipping 10 matching lines @@
             frame_offset -= offset;
           else
             /* Exit loop if a positive stack adjustment is found, which
                usually means that the stack cleanup code in the function
                epilogue is reached.  */
             break;
         }
       else if ((inst & 0xf800) == 0xd000)       /* sw reg,n($sp) */
         {
           offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
-          reg = mips16_to_32_reg[(inst & 0x700) >> 8];
+          reg = mips_reg3_to_reg[(inst & 0x700) >> 8];
           set_reg_offset (gdbarch, this_cache, reg, sp + offset);
         }
       else if ((inst & 0xff00) == 0xf900)       /* sd reg,n($sp) */
         {
           offset = mips16_get_imm (prev_inst, inst, 5, 8, 0);
-          reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+          reg = mips_reg3_to_reg[(inst & 0xe0) >> 5];
           set_reg_offset (gdbarch, this_cache, reg, sp + offset);
         }
       else if ((inst & 0xff00) == 0x6200)       /* sw $ra,n($sp) */
         {
           offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
           set_reg_offset (gdbarch, this_cache, MIPS_RA_REGNUM, sp + offset);
         }
       else if ((inst & 0xff00) == 0xfa00)       /* sd $ra,n($sp) */
         {
           offset = mips16_get_imm (prev_inst, inst, 8, 8, 0);
           set_reg_offset (gdbarch, this_cache, MIPS_RA_REGNUM, sp + offset);
         }
       else if (inst == 0x673d)  /* move $s1, $sp */
         {
           frame_addr = sp;
           frame_reg = 17;
         }
       else if ((inst & 0xff00) == 0x0100)       /* addiu $s1,sp,n */
         {
           offset = mips16_get_imm (prev_inst, inst, 8, 4, 0);
           frame_addr = sp + offset;
           frame_reg = 17;
           frame_adjust = offset;
         }
       else if ((inst & 0xFF00) == 0xd900)       /* sw reg,offset($s1) */
         {
           offset = mips16_get_imm (prev_inst, inst, 5, 4, 0);
-          reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+          reg = mips_reg3_to_reg[(inst & 0xe0) >> 5];
           set_reg_offset (gdbarch, this_cache, reg, frame_addr + offset);
         }
       else if ((inst & 0xFF00) == 0x7900)       /* sd reg,offset($s1) */
         {
           offset = mips16_get_imm (prev_inst, inst, 5, 8, 0);
-          reg = mips16_to_32_reg[(inst & 0xe0) >> 5];
+          reg = mips_reg3_to_reg[(inst & 0xe0) >> 5];
           set_reg_offset (gdbarch, this_cache, reg, frame_addr + offset);
         }
       else if ((inst & 0xf81f) == 0xe809
                && (inst & 0x700) != 0x700)      /* entry */
         entry_inst = inst;      /* Save for later processing.  */
       else if ((inst & 0xff80) == 0x6480)       /* save */
         {
           save_inst = inst;     /* Save for later processing.  */
           if (prev_extend_bytes)                /* extend */
             save_inst |= prev_inst << 16;
@@ skipping 232 matching lines @@
 {
   struct mips_frame_cache *info = mips_insn16_frame_cache (this_frame,
                                                            this_cache);
   return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
 }
 
 static int
 mips_insn16_frame_sniffer (const struct frame_unwind *self,
                            struct frame_info *this_frame, void **this_cache)
 {
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
   CORE_ADDR pc = get_frame_pc (this_frame);
-  if (mips_pc_is_mips16 (pc))
+  if (mips_pc_is_mips16 (gdbarch, pc))
     return 1;
   return 0;
 }
 
 static const struct frame_unwind mips_insn16_frame_unwind =
 {
   NORMAL_FRAME,
   default_frame_unwind_stop_reason,
   mips_insn16_frame_this_id,
   mips_insn16_frame_prev_register,
@@ skipping 14 matching lines @@
 {
   &mips_insn16_frame_unwind,
   mips_insn16_frame_base_address,
   mips_insn16_frame_base_address,
   mips_insn16_frame_base_address
 };
 
 static const struct frame_base *
 mips_insn16_frame_base_sniffer (struct frame_info *this_frame)
 {
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
   CORE_ADDR pc = get_frame_pc (this_frame);
-  if (mips_pc_is_mips16 (pc))
+  if (mips_pc_is_mips16 (gdbarch, pc))
     return &mips_insn16_frame_base;
   else
     return NULL;
 }
+
+/* Decode a 9-bit signed immediate argument of ADDIUSP -- -2 is mapped
+   to -258, -1 -- to -257, 0 -- to 256, 1 -- to 257 and other values are
+   interpreted directly, and then multiplied by 4.  */
+
+static int
+micromips_decode_imm9 (int imm)
+{
+  imm = (imm ^ 0x100) - 0x100;
+  if (imm > -3 && imm < 2)
+    imm ^= 0x100;
+  return imm << 2;
+}
+
+/* Analyze the function prologue from START_PC to LIMIT_PC.  Return
+   the address of the first instruction past the prologue.  */
+
+static CORE_ADDR
+micromips_scan_prologue (struct gdbarch *gdbarch,
+                         CORE_ADDR start_pc, CORE_ADDR limit_pc,
+                         struct frame_info *this_frame,
+                         struct mips_frame_cache *this_cache)
+{
+  CORE_ADDR end_prologue_addr = 0;
+  int prev_non_prologue_insn = 0;
+  int frame_reg = MIPS_SP_REGNUM;
+  int this_non_prologue_insn;
+  int non_prologue_insns = 0;
+  long frame_offset = 0;        /* Size of stack frame.  */
+  long frame_adjust = 0;        /* Offset of FP from SP.  */
+  CORE_ADDR frame_addr = 0;     /* Value of $30, used as frame pointer.  */
+  CORE_ADDR prev_pc;
+  CORE_ADDR cur_pc;
+  ULONGEST insn;                /* current instruction */
+  CORE_ADDR sp;
+  long offset;
+  long sp_adj;
+  long v1_off = 0;              /* The assumption is LUI will replace it.  */
+  int reglist;
+  int breg;
+  int dreg;
+  int sreg;
+  int treg;
+  int loc;
+  int op;
+  int s;
+  int i;
+
+  /* Can be called when there's no process, and hence when there's no
+     THIS_FRAME.  */
+  if (this_frame != NULL)
+    sp = get_frame_register_signed (this_frame,
+                                    gdbarch_num_regs (gdbarch)
+                                    + MIPS_SP_REGNUM);
+  else
+    sp = 0;
+
+  if (limit_pc > start_pc + 200)
+    limit_pc = start_pc + 200;
+  prev_pc = start_pc;
+
+  /* Permit at most one non-prologue non-control-transfer instruction
+     in the middle which may have been reordered by the compiler for
+     optimisation.  */
+  for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += loc)
+    {
+      this_non_prologue_insn = 0;
+      sp_adj = 0;
+      loc = 0;
+      insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, cur_pc, NULL);
+      loc += MIPS_INSN16_SIZE;
+      switch (mips_insn_size (ISA_MICROMIPS, insn))
+        {
+        /* 48-bit instructions.  */
+        case 3 * MIPS_INSN16_SIZE:
+          /* No prologue instructions in this category.  */
+          this_non_prologue_insn = 1;
+          loc += 2 * MIPS_INSN16_SIZE;
+          break;
+
+        /* 32-bit instructions.  */
+        case 2 * MIPS_INSN16_SIZE:
+          insn <<= 16;
+          insn |= mips_fetch_instruction (gdbarch,
+                                          ISA_MICROMIPS, cur_pc + loc, NULL);
+          loc += MIPS_INSN16_SIZE;
+          switch (micromips_op (insn >> 16))
+            {
+            /* Record $sp/$fp adjustment.  */
+            /* Discard (D)ADDU $gp,$jp used for PIC code.  */
+            case 0x0: /* POOL32A: bits 000000 */
+            case 0x16: /* POOL32S: bits 010110 */
+              op = b0s11_op (insn);
+              sreg = b0s5_reg (insn >> 16);
+              treg = b5s5_reg (insn >> 16);
+              dreg = b11s5_reg (insn);
+              if (op == 0x1d0
+                                /* SUBU: bits 000000 00111010000 */
+                                /* DSUBU: bits 010110 00111010000 */
+                  && dreg == MIPS_SP_REGNUM && sreg == MIPS_SP_REGNUM
+                  && treg == 3)
+                                /* (D)SUBU $sp, $v1 */
+                    sp_adj = v1_off;
+              else if (op != 0x150
+                                /* ADDU: bits 000000 00101010000 */
+                                /* DADDU: bits 010110 00101010000 */
+                       || dreg != 28 || sreg != 28 || treg != MIPS_T9_REGNUM)
+                this_non_prologue_insn = 1;
+              break;
+
+            case 0x8: /* POOL32B: bits 001000 */
+              op = b12s4_op (insn);
+              breg = b0s5_reg (insn >> 16);
+              reglist = sreg = b5s5_reg (insn >> 16);
+              offset = (b0s12_imm (insn) ^ 0x800) - 0x800;
+              if ((op == 0x9 || op == 0xc)
+                                /* SWP: bits 001000 1001 */
+                                /* SDP: bits 001000 1100 */
+                  && breg == MIPS_SP_REGNUM && sreg < MIPS_RA_REGNUM)
+                                /* S[DW]P reg,offset($sp) */
+                {
+                  s = 4 << ((b12s4_op (insn) & 0x4) == 0x4);
+                  set_reg_offset (gdbarch, this_cache,
+                                  sreg, sp + offset);
+                  set_reg_offset (gdbarch, this_cache,
+                                  sreg + 1, sp + offset + s);
+                }
+              else if ((op == 0xd || op == 0xf)
+                                /* SWM: bits 001000 1101 */
+                                /* SDM: bits 001000 1111 */
+                       && breg == MIPS_SP_REGNUM
+                                /* SWM reglist,offset($sp) */
+                       && ((reglist >= 1 && reglist <= 9)
+                           || (reglist >= 16 && reglist <= 25)))
+                {
+                  int sreglist = min(reglist & 0xf, 8);
+
+                  s = 4 << ((b12s4_op (insn) & 0x2) == 0x2);
+                  for (i = 0; i < sreglist; i++)
+                    set_reg_offset (gdbarch, this_cache, 16 + i, sp + s * i);
+                  if ((reglist & 0xf) > 8)
+                    set_reg_offset (gdbarch, this_cache, 30, sp + s * i++);
+                  if ((reglist & 0x10) == 0x10)
+                    set_reg_offset (gdbarch, this_cache,
+                                    MIPS_RA_REGNUM, sp + s * i++);
+                }
+              else
+                this_non_prologue_insn = 1;
+              break;
+
+            /* Record $sp/$fp adjustment.  */
+            /* Discard (D)ADDIU $gp used for PIC code.  */
+            case 0xc: /* ADDIU: bits 001100 */
+            case 0x17: /* DADDIU: bits 010111 */
+              sreg = b0s5_reg (insn >> 16);
+              dreg = b5s5_reg (insn >> 16);
+              offset = (b0s16_imm (insn) ^ 0x8000) - 0x8000;
+              if (sreg == MIPS_SP_REGNUM && dreg == MIPS_SP_REGNUM)
+                                /* (D)ADDIU $sp, imm */
+                sp_adj = offset;
+              else if (sreg == MIPS_SP_REGNUM && dreg == 30)
+                                /* (D)ADDIU $fp, $sp, imm */
+                {
+                  frame_addr = sp + offset;
+                  frame_adjust = offset;
+                  frame_reg = 30;
+                }
+              else if (sreg != 28 || dreg != 28)
+                                /* (D)ADDIU $gp, imm */
+                this_non_prologue_insn = 1;
+              break;
+
+            /* LUI $v1 is used for larger $sp adjustments.  */
+            /* Discard LUI $gp is used for PIC code.  */
+            case 0x10: /* POOL32I: bits 010000 */
+              if (b5s5_op (insn >> 16) == 0xd
+                                /* LUI: bits 010000 001101 */
+                  && b0s5_reg (insn >> 16) == 3)
+                                /* LUI $v1, imm */
+                v1_off = ((b0s16_imm (insn) << 16) ^ 0x80000000) - 0x80000000;
+              else if (b5s5_op (insn >> 16) != 0xd
+                                /* LUI: bits 010000 001101 */
+                       || b0s5_reg (insn >> 16) != 28)
+                                /* LUI $gp, imm */
+                this_non_prologue_insn = 1;
+              break;
+
+            /* ORI $v1 is used for larger $sp adjustments.  */
+            case 0x14: /* ORI: bits 010100 */
+              sreg = b0s5_reg (insn >> 16);
+              dreg = b5s5_reg (insn >> 16);
+              if (sreg == 3 && dreg == 3)
+                                /* ORI $v1, imm */
+                v1_off |= b0s16_imm (insn);
+              else
+                this_non_prologue_insn = 1;
+              break;
+
+            case 0x26: /* SWC1: bits 100110 */
+            case 0x2e: /* SDC1: bits 101110 */
+              breg = b0s5_reg (insn >> 16);
+              if (breg != MIPS_SP_REGNUM)
+                                /* S[DW]C1 reg,offset($sp) */
+                this_non_prologue_insn = 1;
+              break;
+
+            case 0x36: /* SD: bits 110110 */
+            case 0x3e: /* SW: bits 111110 */
+              breg = b0s5_reg (insn >> 16);
+              sreg = b5s5_reg (insn >> 16);
+              offset = (b0s16_imm (insn) ^ 0x8000) - 0x8000;
+              if (breg == MIPS_SP_REGNUM)
+                                /* S[DW] reg,offset($sp) */
+                set_reg_offset (gdbarch, this_cache, sreg, sp + offset);
+              else
+                this_non_prologue_insn = 1;
+              break;
+
+            default:
+              this_non_prologue_insn = 1;
+              break;
+            }
+          break;
+
+        /* 16-bit instructions.  */
+        case MIPS_INSN16_SIZE:
+          switch (micromips_op (insn))
+            {
+            case 0x3: /* MOVE: bits 000011 */
+              sreg = b0s5_reg (insn);
+              dreg = b5s5_reg (insn);
+              if (sreg == MIPS_SP_REGNUM && dreg == 30)
+                                /* MOVE  $fp, $sp */
+                {
+                  frame_addr = sp;
+                  frame_reg = 30;
+                }
+              else if ((sreg & 0x1c) != 0x4)
+                                /* MOVE  reg, $a0-$a3 */
+                this_non_prologue_insn = 1;
+              break;
+
+            case 0x11: /* POOL16C: bits 010001 */
+              if (b6s4_op (insn) == 0x5)
+                                /* SWM: bits 010001 0101 */
+                {
+                  offset = ((b0s4_imm (insn) << 2) ^ 0x20) - 0x20;
+                  reglist = b4s2_regl (insn);
+                  for (i = 0; i <= reglist; i++)
+                    set_reg_offset (gdbarch, this_cache, 16 + i, sp + 4 * i);
+                  set_reg_offset (gdbarch, this_cache,
+                                  MIPS_RA_REGNUM, sp + 4 * i++);
+                }
+              else
+                this_non_prologue_insn = 1;
+              break;
+
+            case 0x13: /* POOL16D: bits 010011 */
+              if ((insn & 0x1) == 0x1)
+                                /* ADDIUSP: bits 010011 1 */
+                sp_adj = micromips_decode_imm9 (b1s9_imm (insn));
+              else if (b5s5_reg (insn) == MIPS_SP_REGNUM)
+                                /* ADDIUS5: bits 010011 0 */
+                                /* ADDIUS5 $sp, imm */
+                sp_adj = (b1s4_imm (insn) ^ 8) - 8;
+              else
+                this_non_prologue_insn = 1;
+              break;
+
+            case 0x32: /* SWSP: bits 110010 */
+              offset = b0s5_imm (insn) << 2;
+              sreg = b5s5_reg (insn);
+              set_reg_offset (gdbarch, this_cache, sreg, sp + offset);
+              break;
+
+            default:
+              this_non_prologue_insn = 1;
+              break;
+            }
+          break;
+        }
+      if (sp_adj < 0)
+        frame_offset -= sp_adj;
+
+      non_prologue_insns += this_non_prologue_insn;
+      /* Enough non-prologue insns seen or positive stack adjustment? */
+      if (end_prologue_addr == 0 && (non_prologue_insns > 1 || sp_adj > 0))
+        {
+          end_prologue_addr = prev_non_prologue_insn ? prev_pc : cur_pc;
+          break;
+        }
+      prev_non_prologue_insn = this_non_prologue_insn;
+      prev_pc = cur_pc;
+    }
+
+  if (this_cache != NULL)
+    {
+      this_cache->base =
+        (get_frame_register_signed (this_frame,
+                                    gdbarch_num_regs (gdbarch) + frame_reg)
+         + frame_offset - frame_adjust);
+      /* FIXME: brobecker/2004-10-10: Just as in the mips32 case, we should
+         be able to get rid of the assignment below, evetually. But it's
+         still needed for now.  */
+      this_cache->saved_regs[gdbarch_num_regs (gdbarch)
+                             + mips_regnum (gdbarch)->pc]
+        = this_cache->saved_regs[gdbarch_num_regs (gdbarch) + MIPS_RA_REGNUM];
+    }
+
+  /* If we didn't reach the end of the prologue when scanning the function
+     instructions, then set end_prologue_addr to the address of the
+     instruction immediately after the last one we scanned.  Unless the
+     last one looked like a non-prologue instruction (and we looked ahead),
+     in which case use its address instead.  */
+  if (end_prologue_addr == 0)
+    end_prologue_addr = prev_non_prologue_insn ? prev_pc : cur_pc;
+
+  return end_prologue_addr;
+}
+
+/* Heuristic unwinder for procedures using microMIPS instructions.
+   Procedures that use the 32-bit instruction set are handled by the
+   mips_insn32 unwinder.  Likewise MIPS16 and the mips_insn16 unwinder. */
+
+static struct mips_frame_cache *
+mips_micro_frame_cache (struct frame_info *this_frame, void **this_cache)
+{
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
+  struct mips_frame_cache *cache;
+
+  if ((*this_cache) != NULL)
+    return (*this_cache);
+
+  cache = FRAME_OBSTACK_ZALLOC (struct mips_frame_cache);
+  (*this_cache) = cache;
+  cache->saved_regs = trad_frame_alloc_saved_regs (this_frame);
+
+  /* Analyze the function prologue.  */
+  {
+    const CORE_ADDR pc = get_frame_address_in_block (this_frame);
+    CORE_ADDR start_addr;
+
+    find_pc_partial_function (pc, NULL, &start_addr, NULL);
+    if (start_addr == 0)
+      start_addr = heuristic_proc_start (get_frame_arch (this_frame), pc);
+    /* We can't analyze the prologue if we couldn't find the begining
+       of the function.  */
+    if (start_addr == 0)
+      return cache;
+
+    micromips_scan_prologue (gdbarch, start_addr, pc, this_frame, *this_cache);
+  }
+
+  /* gdbarch_sp_regnum contains the value and not the address.  */
+  trad_frame_set_value (cache->saved_regs,
+                        gdbarch_num_regs (gdbarch) + MIPS_SP_REGNUM,
+                        cache->base);
+
+  return (*this_cache);
+}
+
+static void
+mips_micro_frame_this_id (struct frame_info *this_frame, void **this_cache,
+                          struct frame_id *this_id)
+{
+  struct mips_frame_cache *info = mips_micro_frame_cache (this_frame,
+                                                          this_cache);
+  /* This marks the outermost frame.  */
+  if (info->base == 0)
+    return;
+  (*this_id) = frame_id_build (info->base, get_frame_func (this_frame));
+}
+
+static struct value *
+mips_micro_frame_prev_register (struct frame_info *this_frame,
+                                void **this_cache, int regnum)
+{
+  struct mips_frame_cache *info = mips_micro_frame_cache (this_frame,
+                                                          this_cache);
+  return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
+}
+
+static int
+mips_micro_frame_sniffer (const struct frame_unwind *self,
+                          struct frame_info *this_frame, void **this_cache)
+{
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
+  CORE_ADDR pc = get_frame_pc (this_frame);
+
+  if (mips_pc_is_micromips (gdbarch, pc))
+    return 1;
+  return 0;
+}
+
+static const struct frame_unwind mips_micro_frame_unwind =
+{
+  NORMAL_FRAME,
+  default_frame_unwind_stop_reason,
+  mips_micro_frame_this_id,
+  mips_micro_frame_prev_register,
+  NULL,
+  mips_micro_frame_sniffer
+};
+
+static CORE_ADDR
+mips_micro_frame_base_address (struct frame_info *this_frame,
+                               void **this_cache)
+{
+  struct mips_frame_cache *info = mips_micro_frame_cache (this_frame,
+                                                          this_cache);
+  return info->base;
+}
+
+static const struct frame_base mips_micro_frame_base =
+{
+  &mips_micro_frame_unwind,
+  mips_micro_frame_base_address,
+  mips_micro_frame_base_address,
+  mips_micro_frame_base_address
+};
+
+static const struct frame_base *
+mips_micro_frame_base_sniffer (struct frame_info *this_frame)
+{
+  struct gdbarch *gdbarch = get_frame_arch (this_frame);
+  CORE_ADDR pc = get_frame_pc (this_frame);
+
+  if (mips_pc_is_micromips (gdbarch, pc))
+    return &mips_micro_frame_base;
+  else
+    return NULL;
+}
 
 /* Mark all the registers as unset in the saved_regs array
    of THIS_CACHE.  Do nothing if THIS_CACHE is null.  */
 
 static void
 reset_saved_regs (struct gdbarch *gdbarch, struct mips_frame_cache *this_cache)
 {
   if (this_cache == NULL || this_cache->saved_regs == NULL)
     return;
 
@@ skipping 45 matching lines @@
 
 restart:
 
   frame_offset = 0;
   for (cur_pc = start_pc; cur_pc < limit_pc; cur_pc += MIPS_INSN32_SIZE)
     {
       unsigned long inst, high_word, low_word;
       int reg;
 
       /* Fetch the instruction.  */
-      inst = (unsigned long) mips_fetch_instruction (gdbarch, cur_pc);
+      inst = (unsigned long) mips_fetch_instruction (gdbarch, ISA_MIPS,
+                                                     cur_pc, NULL);
 
       /* Save some code by pre-extracting some useful fields.  */
       high_word = (inst >> 16) & 0xffff;
       low_word = inst & 0xffff;
       reg = high_word & 0x1f;
 
       if (high_word == 0x27bd           /* addiu $sp,$sp,-i */
           || high_word == 0x23bd        /* addi $sp,$sp,-i */
           || high_word == 0x67bd)       /* daddiu $sp,$sp,-i */
         {
@@ skipping 82 matching lines @@
           set_reg_offset (gdbarch, this_cache, reg, frame_addr + low_word);
         }
       else if ((high_word & 0xFFE0) == 0xE7A0 /* swc1 freg,n($sp) */
                || (high_word & 0xF3E0) == 0xA3C0 /* sx reg,n($s8) */
                || (inst & 0xFF9F07FF) == 0x00800021 /* move reg,$a0-$a3 */
                || high_word == 0x3c1c /* lui $gp,n */
                || high_word == 0x279c /* addiu $gp,$gp,n */
                || inst == 0x0399e021 /* addu $gp,$gp,$t9 */
                || inst == 0x033ce021 /* addu $gp,$t9,$gp */
               )
-       {
-         /* These instructions are part of the prologue, but we don't
-            need to do anything special to handle them.  */
-       }
+        {
+          /* These instructions are part of the prologue, but we don't
+             need to do anything special to handle them.  */
+        }
       /* The instructions below load $at or $t0 with an immediate
          value in preparation for a stack adjustment via
          subu $sp,$sp,[$at,$t0].  These instructions could also
          initialize a local variable, so we accept them only before
          a stack adjustment instruction was seen.  */
       else if (!seen_sp_adjust
-               && (high_word == 0x3c01 /* lui $at,n */
-                   || high_word == 0x3c08 /* lui $t0,n */
-                   || high_word == 0x3421 /* ori $at,$at,n */
-                   || high_word == 0x3508 /* ori $t0,$t0,n */
-                   || high_word == 0x3401 /* ori $at,$zero,n */
-                   || high_word == 0x3408 /* ori $t0,$zero,n */
-                  ))
-       {
-         if (end_prologue_addr == 0)
-           load_immediate_bytes += MIPS_INSN32_SIZE;            /* FIXME!  */
-       }
+               && (high_word == 0x3c01 /* lui $at,n */
+                   || high_word == 0x3c08 /* lui $t0,n */
+                   || high_word == 0x3421 /* ori $at,$at,n */
+                   || high_word == 0x3508 /* ori $t0,$t0,n */
+                   || high_word == 0x3401 /* ori $at,$zero,n */
+                   || high_word == 0x3408 /* ori $t0,$zero,n */
+                  ))
+        {
+          if (end_prologue_addr == 0)
+            load_immediate_bytes += MIPS_INSN32_SIZE;           /* FIXME!  */
+        }
       else
-       {
-         /* This instruction is not an instruction typically found
-            in a prologue, so we must have reached the end of the
-            prologue.  */
-         /* FIXME: brobecker/2004-10-10: Can't we just break out of this
-            loop now?  Why would we need to continue scanning the function
-            instructions?  */
-         if (end_prologue_addr == 0)
-           end_prologue_addr = cur_pc;
+        {
+          /* This instruction is not an instruction typically found
+             in a prologue, so we must have reached the end of the
+             prologue.  */
+          /* FIXME: brobecker/2004-10-10: Can't we just break out of this
+             loop now?  Why would we need to continue scanning the function
+             instructions?  */
+          if (end_prologue_addr == 0)
+            end_prologue_addr = cur_pc;
 
-         /* Check for branches and jumps.  For now, only jump to
-            register are caught (i.e. returns).  */
-         if ((itype_op (inst) & 0x07) == 0 && rtype_funct (inst) == 8)
-           in_delay_slot = 1;
-       }
+          /* Check for branches and jumps.  For now, only jump to
+             register are caught (i.e. returns).  */
+          if ((itype_op (inst) & 0x07) == 0 && rtype_funct (inst) == 8)
+            in_delay_slot = 1;
+        }
 
       /* If the previous instruction was a jump, we must have reached
          the end of the prologue by now.  Stop scanning so that we do
          not go past the function return.  */
       if (in_delay_slot)
         break;
     }
 
   if (this_cache != NULL)
     {
@@ skipping 24 matching lines @@
      if the load immediate was not followed by a stack adjustment.  */
   if (load_immediate_bytes && !seen_sp_adjust)
     end_prologue_addr -= load_immediate_bytes;
 
   return end_prologue_addr;
 }
 
 /* Heuristic unwinder for procedures using 32-bit instructions (covers
    both 32-bit and 64-bit MIPS ISAs).  Procedures using 16-bit
    instructions (a.k.a. MIPS16) are handled by the mips_insn16
-   unwinder.  */
+   unwinder.  Likewise microMIPS and the mips_micro unwinder. */
 
 static struct mips_frame_cache *
 mips_insn32_frame_cache (struct frame_info *this_frame, void **this_cache)
 {
   struct gdbarch *gdbarch = get_frame_arch (this_frame);
   struct mips_frame_cache *cache;
 
   if ((*this_cache) != NULL)
     return (*this_cache);
 
@@ skipping 44 matching lines @@
   struct mips_frame_cache *info = mips_insn32_frame_cache (this_frame,
                                                            this_cache);
   return trad_frame_get_prev_register (this_frame, info->saved_regs, regnum);
 }
 
 static int
 mips_insn32_frame_sniffer (const struct frame_unwind *self,
                            struct frame_info *this_frame, void **this_cache)
 {
   CORE_ADDR pc = get_frame_pc (this_frame);
-  if (! mips_pc_is_mips16 (pc))
+  if (mips_pc_is_mips (pc))
     return 1;
   return 0;
 }
 
 static const struct frame_unwind mips_insn32_frame_unwind =
 {
   NORMAL_FRAME,
   default_frame_unwind_stop_reason,
   mips_insn32_frame_this_id,
   mips_insn32_frame_prev_register,
@@ skipping 15 matching lines @@
   &mips_insn32_frame_unwind,
   mips_insn32_frame_base_address,
   mips_insn32_frame_base_address,
   mips_insn32_frame_base_address
 };
 
 static const struct frame_base *
 mips_insn32_frame_base_sniffer (struct frame_info *this_frame)
 {
   CORE_ADDR pc = get_frame_pc (this_frame);
-  if (! mips_pc_is_mips16 (pc))
+  if (mips_pc_is_mips (pc))
     return &mips_insn32_frame_base;
   else
     return NULL;
 }
 
 static struct trad_frame_cache *
 mips_stub_frame_cache (struct frame_info *this_frame, void **this_cache)
 {
   CORE_ADDR pc;
   CORE_ADDR start_addr;
@@ skipping 116 matching lines @@
     return NULL;
 }
 
 /* mips_addr_bits_remove - remove useless address bits  */
 
 static CORE_ADDR
 mips_addr_bits_remove (struct gdbarch *gdbarch, CORE_ADDR addr)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 
-  if (is_mips16_addr (addr))
-    addr = unmake_mips16_addr (addr);
+  if (is_compact_addr (addr))
+    addr = unmake_compact_addr (addr);
 
   if (mips_mask_address_p (tdep) && (((ULONGEST) addr) >> 32 == 0xffffffffUL))
     /* This hack is a work-around for existing boards using PMON, the
        simulator, and any other 64-bit targets that doesn't have true
        64-bit addressing.  On these targets, the upper 32 bits of
        addresses are ignored by the hardware.  Thus, the PC or SP are
        likely to have been sign extended to all 1s by instruction
        sequences that load 32-bit addresses.  For example, a typical
        piece of code that loads an address is this:
 
        lui $r2, <upper 16 bits>
        ori $r2, <lower 16 bits>
 
        But the lui sign-extends the value such that the upper 32 bits
        may be all 1s.  The workaround is simply to mask off these
        bits.  In the future, gcc may be changed to support true 64-bit
        addressing, and this masking will have to be disabled.  */
     return addr &= 0xffffffffUL;
   else
     return addr;
 }
 
-/* Instructions used during single-stepping of atomic sequences.  */
-#define LL_OPCODE 0x30
-#define LLD_OPCODE 0x34
-#define SC_OPCODE 0x38
-#define SCD_OPCODE 0x3c
 
 /* Checks for an atomic sequence of instructions beginning with a LL/LLD
    instruction and ending with a SC/SCD instruction.  If such a sequence
    is found, attempt to step through it.  A breakpoint is placed at the end of 
    the sequence.  */
 
+/* Instructions used during single-stepping of atomic sequences, standard
+   ISA version.  */
+#define LL_OPCODE 0x30
+#define LLD_OPCODE 0x34
+#define SC_OPCODE 0x38
+#define SCD_OPCODE 0x3c
+
 static int
-deal_with_atomic_sequence (struct gdbarch *gdbarch,
-                           struct address_space *aspace, CORE_ADDR pc)
+mips_deal_with_atomic_sequence (struct gdbarch *gdbarch,
+                                struct address_space *aspace, CORE_ADDR pc)
 {
   CORE_ADDR breaks[2] = {-1, -1};
   CORE_ADDR loc = pc;
   CORE_ADDR branch_bp; /* Breakpoint at branch instruction's destination.  */
-  unsigned long insn;
+  ULONGEST insn;
   int insn_count;
   int index;
   int last_breakpoint = 0; /* Defaults to 0 (no breakpoints placed).  */  
   const int atomic_sequence_length = 16; /* Instruction sequence length.  */
 
-  if (pc & 0x01)
-    return 0;
-
-  insn = mips_fetch_instruction (gdbarch, loc);
+  insn = mips_fetch_instruction (gdbarch, ISA_MIPS, loc, NULL);
   /* Assume all atomic sequences start with a ll/lld instruction.  */
   if (itype_op (insn) != LL_OPCODE && itype_op (insn) != LLD_OPCODE)
     return 0;
 
   /* Assume that no atomic sequence is longer than "atomic_sequence_length" 
      instructions.  */
   for (insn_count = 0; insn_count < atomic_sequence_length; ++insn_count)
     {
       int is_branch = 0;
       loc += MIPS_INSN32_SIZE;
-      insn = mips_fetch_instruction (gdbarch, loc);
+      insn = mips_fetch_instruction (gdbarch, ISA_MIPS, loc, NULL);
 
       /* Assume that there is at most one branch in the atomic
          sequence.  If a branch is found, put a breakpoint in its
          destination address.  */
       switch (itype_op (insn))
         {
         case 0: /* SPECIAL */
           if (rtype_funct (insn) >> 1 == 4) /* JR, JALR */
             return 0; /* fallback to the standard single-step code.  */
           break;
         case 1: /* REGIMM */
-          is_branch = ((itype_rt (insn) & 0xc) == 0); /* B{LT,GE}Z* */
+          is_branch = ((itype_rt (insn) & 0xc) == 0 /* B{LT,GE}Z* */
+                       || ((itype_rt (insn) & 0x1e) == 0
+                           && itype_rs (insn) == 0)); /* BPOSGE* */
           break;
         case 2: /* J */
         case 3: /* JAL */
           return 0; /* fallback to the standard single-step code.  */
         case 4: /* BEQ */
         case 5: /* BNE */
         case 6: /* BLEZ */
         case 7: /* BGTZ */
         case 20: /* BEQL */
         case 21: /* BNEL */
         case 22: /* BLEZL */
         case 23: /* BGTTL */
           is_branch = 1;
           break;
         case 17: /* COP1 */
+          is_branch = ((itype_rs (insn) == 9 || itype_rs (insn) == 10)
+                       && (itype_rt (insn) & 0x2) == 0);
+          if (is_branch) /* BC1ANY2F, BC1ANY2T, BC1ANY4F, BC1ANY4T */
+            break;
+        /* Fall through.  */
         case 18: /* COP2 */
         case 19: /* COP3 */
           is_branch = (itype_rs (insn) == 8); /* BCzF, BCzFL, BCzT, BCzTL */
           break;
         }
       if (is_branch)
         {
           branch_bp = loc + mips32_relative_offset (insn) + 4;
           if (last_breakpoint >= 1)
             return 0; /* More than one branch found, fallback to the
@@ skipping 20 matching lines @@
   if (last_breakpoint && pc <= breaks[1] && breaks[1] <= breaks[0])
     last_breakpoint = 0;
 
   /* Effectively inserts the breakpoints.  */
   for (index = 0; index <= last_breakpoint; index++)
     insert_single_step_breakpoint (gdbarch, aspace, breaks[index]);
 
   return 1;
 }
 
+static int
+micromips_deal_with_atomic_sequence (struct gdbarch *gdbarch,
+                                     struct address_space *aspace,
+                                     CORE_ADDR pc)
+{
+  const int atomic_sequence_length = 16; /* Instruction sequence length.  */
+  int last_breakpoint = 0; /* Defaults to 0 (no breakpoints placed).  */
+  CORE_ADDR breaks[2] = {-1, -1};
+  CORE_ADDR branch_bp; /* Breakpoint at branch instruction's destination.  */
+  CORE_ADDR loc = pc;
+  int sc_found = 0;
+  ULONGEST insn;
+  int insn_count;
+  int index;
+
+  /* Assume all atomic sequences start with a ll/lld instruction.  */
+  insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, loc, NULL);
+  if (micromips_op (insn) != 0x18)      /* POOL32C: bits 011000 */
+    return 0;
+  loc += MIPS_INSN16_SIZE;
+  insn <<= 16;
+  insn |= mips_fetch_instruction (gdbarch, ISA_MICROMIPS, loc, NULL);
+  if ((b12s4_op (insn) & 0xb) != 0x3)   /* LL, LLD: bits 011000 0x11 */
+    return 0;
+  loc += MIPS_INSN16_SIZE;
+
+  /* Assume all atomic sequences end with an sc/scd instruction.  Assume
+     that no atomic sequence is longer than "atomic_sequence_length"
+     instructions.  */
+  for (insn_count = 0;
+       !sc_found && insn_count < atomic_sequence_length;
+       ++insn_count)
+    {
+      int is_branch = 0;
+
+      insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, loc, NULL);
+      loc += MIPS_INSN16_SIZE;
+
+      /* Assume that there is at most one conditional branch in the
+         atomic sequence.  If a branch is found, put a breakpoint in
+         its destination address.  */
+      switch (mips_insn_size (ISA_MICROMIPS, insn))
+        {
+        /* 48-bit instructions.  */
+        case 3 * MIPS_INSN16_SIZE: /* POOL48A: bits 011111 */
+          loc += 2 * MIPS_INSN16_SIZE;
+          break;
+
+        /* 32-bit instructions.  */
+        case 2 * MIPS_INSN16_SIZE:
+          switch (micromips_op (insn))
+            {
+            case 0x10: /* POOL32I: bits 010000 */
+              if ((b5s5_op (insn) & 0x18) != 0x0
+                                /* BLTZ, BLTZAL, BGEZ, BGEZAL: 010000 000xx */
+                                /* BLEZ, BNEZC, BGTZ, BEQZC: 010000 001xx */
+                  && (b5s5_op (insn) & 0x1d) != 0x11
+                                /* BLTZALS, BGEZALS: bits 010000 100x1 */
+                  && ((b5s5_op (insn) & 0x1e) != 0x14
+                      || (insn & 0x3) != 0x0)
+                                /* BC2F, BC2T: bits 010000 1010x xxx00 */
+                  && (b5s5_op (insn) & 0x1e) != 0x1a
+                                /* BPOSGE64, BPOSGE32: bits 010000 1101x */
+                  && ((b5s5_op (insn) & 0x1e) != 0x1c
+                      || (insn & 0x3) != 0x0)
+                                /* BC1F, BC1T: bits 010000 1110x xxx00 */
+                  && ((b5s5_op (insn) & 0x1c) != 0x1c
+                      || (insn & 0x3) != 0x1))
+                                /* BC1ANY*: bits 010000 111xx xxx01 */
+                break;
+              /* Fall through.  */
+
+            case 0x25: /* BEQ: bits 100101 */
+            case 0x2d: /* BNE: bits 101101 */
+              insn <<= 16;
+              insn |= mips_fetch_instruction (gdbarch,
+                                              ISA_MICROMIPS, loc, NULL);
+              branch_bp = (loc + MIPS_INSN16_SIZE
+                           + micromips_relative_offset16 (insn));
+              is_branch = 1;
+              break;
+
+            case 0x00: /* POOL32A: bits 000000 */
+              insn <<= 16;
+              insn |= mips_fetch_instruction (gdbarch,
+                                              ISA_MICROMIPS, loc, NULL);
+              if (b0s6_op (insn) != 0x3c
+                                /* POOL32Axf: bits 000000 ... 111100 */
+                  || (b6s10_ext (insn) & 0x2bf) != 0x3c)
+                                /* JALR, JALR.HB: 000000 000x111100 111100 */
+                                /* JALRS, JALRS.HB: 000000 010x111100 111100 */
+                break;
+              /* Fall through.  */
+
+            case 0x1d: /* JALS: bits 011101 */
+            case 0x35: /* J: bits 110101 */
+            case 0x3d: /* JAL: bits 111101 */
+            case 0x3c: /* JALX: bits 111100 */
+              return 0; /* Fall back to the standard single-step code. */
+
+            case 0x18: /* POOL32C: bits 011000 */
+              if ((b12s4_op (insn) & 0xb) == 0xb)
+                                /* SC, SCD: bits 011000 1x11 */
+                sc_found = 1;
+              break;
+            }
+          loc += MIPS_INSN16_SIZE;
+          break;
+
+        /* 16-bit instructions.  */
+        case MIPS_INSN16_SIZE:
+          switch (micromips_op (insn))
+            {
+            case 0x23: /* BEQZ16: bits 100011 */
+            case 0x2b: /* BNEZ16: bits 101011 */
+              branch_bp = loc + micromips_relative_offset7 (insn);
+              is_branch = 1;
+              break;
+
+            case 0x11: /* POOL16C: bits 010001 */
+              if ((b5s5_op (insn) & 0x1c) != 0xc
+                                /* JR16, JRC, JALR16, JALRS16: 010001 011xx */
+                  && b5s5_op (insn) != 0x18)
+                                /* JRADDIUSP: bits 010001 11000 */
+                break;
+              return 0; /* Fall back to the standard single-step code. */
+
+            case 0x33: /* B16: bits 110011 */
+              return 0; /* Fall back to the standard single-step code. */
+            }
+          break;
+        }
+      if (is_branch)
+        {
+          if (last_breakpoint >= 1)
+            return 0; /* More than one branch found, fallback to the
+                         standard single-step code.  */
+          breaks[1] = branch_bp;
+          last_breakpoint++;
+        }
+    }
+  if (!sc_found)
+    return 0;
+
+  /* Insert a breakpoint right after the end of the atomic sequence.  */
+  breaks[0] = loc;
+
+  /* Check for duplicated breakpoints.  Check also for a breakpoint
+     placed (branch instruction's destination) in the atomic sequence */
+  if (last_breakpoint && pc <= breaks[1] && breaks[1] <= breaks[0])
+    last_breakpoint = 0;
+
+  /* Effectively inserts the breakpoints.  */
+  for (index = 0; index <= last_breakpoint; index++)
+      insert_single_step_breakpoint (gdbarch, aspace, breaks[index]);
+
+  return 1;
+}
+
+static int
+deal_with_atomic_sequence (struct gdbarch *gdbarch,
+                           struct address_space *aspace, CORE_ADDR pc)
+{
+  if (mips_pc_is_mips (pc))
+    return mips_deal_with_atomic_sequence (gdbarch, aspace, pc);
+  else if (mips_pc_is_micromips (gdbarch, pc))
+    return micromips_deal_with_atomic_sequence (gdbarch, aspace, pc);
+  else
+    return 0;
+}
+
 /* mips_software_single_step() is called just before we want to resume
    the inferior, if we want to single-step it but there is no hardware
    or kernel single-step support (MIPS on GNU/Linux for example).  We find
    the target of the coming instruction and breakpoint it.  */
 
 int
 mips_software_single_step (struct frame_info *frame)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
   struct address_space *aspace = get_frame_address_space (frame);
   CORE_ADDR pc, next_pc;
 
   pc = get_frame_pc (frame);
   if (deal_with_atomic_sequence (gdbarch, aspace, pc))
     return 1;
 
   next_pc = mips_next_pc (frame, pc);
 
   insert_single_step_breakpoint (gdbarch, aspace, next_pc);
   return 1;
 }
 
 /* Test whether the PC points to the return instruction at the
    end of a function.  */
 
 static int
 mips_about_to_return (struct gdbarch *gdbarch, CORE_ADDR pc)
 {
-  if (mips_pc_is_mips16 (pc))
-    /* This mips16 case isn't necessarily reliable.  Sometimes the compiler
-       generates a "jr $ra"; other times it generates code to load
-       the return address from the stack to an accessible register (such
-       as $a3), then a "jr" using that register.  This second case
-       is almost impossible to distinguish from an indirect jump
-       used for switch statements, so we don't even try.  */
-    return mips_fetch_instruction (gdbarch, pc) == 0xe820;      /* jr $ra */
-  else
-    return mips_fetch_instruction (gdbarch, pc) == 0x3e00008;   /* jr $ra */
+  ULONGEST insn;
+  ULONGEST hint;
+
+  /* This used to check for MIPS16, but this piece of code is never
+     called for MIPS16 functions.  And likewise microMIPS ones.  */
+  gdb_assert (mips_pc_is_mips (pc));
+
+  insn = mips_fetch_instruction (gdbarch, ISA_MIPS, pc, NULL);
+  hint = 0x7c0;
+  return (insn & ~hint) == 0x3e00008;                   /* jr(.hb) $ra */
 }
 
 
 /* This fencepost looks highly suspicious to me.  Removing it also
    seems suspicious as it could affect remote debugging across serial
    lines.  */
 
 static CORE_ADDR
 heuristic_proc_start (struct gdbarch *gdbarch, CORE_ADDR pc)
 {
   CORE_ADDR start_pc;
   CORE_ADDR fence;
   int instlen;
   int seen_adjsp = 0;
   struct inferior *inf;
 
   pc = gdbarch_addr_bits_remove (gdbarch, pc);
   start_pc = pc;
   fence = start_pc - heuristic_fence_post;
   if (start_pc == 0)
     return 0;
 
   if (heuristic_fence_post == UINT_MAX || fence < VM_MIN_ADDRESS)
     fence = VM_MIN_ADDRESS;
 
-  instlen = mips_pc_is_mips16 (pc) ? MIPS_INSN16_SIZE : MIPS_INSN32_SIZE;
+  instlen = mips_pc_is_mips (pc) ? MIPS_INSN32_SIZE : MIPS_INSN16_SIZE;
 
   inf = current_inferior ();
 
   /* Search back for previous return.  */
   for (start_pc -= instlen;; start_pc -= instlen)
     if (start_pc < fence)
       {
         /* It's not clear to me why we reach this point when
            stop_soon, but with this test, at least we
            don't print out warnings for every child forked (eg, on
@@ skipping 24 matching lines @@
 from %s for code which looks like the beginning of a\n\
 function, you can increase the range of the search using the `set\n\
 heuristic-fence-post' command.\n",
                         paddress (gdbarch, pc), paddress (gdbarch, pc));
                 blurb_printed = 1;
               }
           }
 
         return 0;
       }
-    else if (mips_pc_is_mips16 (start_pc))
+    else if (mips_pc_is_mips16 (gdbarch, start_pc))
       {
         unsigned short inst;
 
         /* On MIPS16, any one of the following is likely to be the
            start of a function:
            extend save
            save
            entry
            addiu sp,-n
            daddiu sp,-n
            extend -n followed by 'addiu sp,+n' or 'daddiu sp,+n'.  */
-        inst = mips_fetch_instruction (gdbarch, start_pc);
+        inst = mips_fetch_instruction (gdbarch, ISA_MIPS16, start_pc, NULL);
         if ((inst & 0xff80) == 0x6480)          /* save */
           {
             if (start_pc - instlen >= fence)
               {
-                inst = mips_fetch_instruction (gdbarch, start_pc - instlen);
+                inst = mips_fetch_instruction (gdbarch, ISA_MIPS16,
+                                               start_pc - instlen, NULL);
                 if ((inst & 0xf800) == 0xf000)  /* extend */
                   start_pc -= instlen;
               }
             break;
           }
         else if (((inst & 0xf81f) == 0xe809
                   && (inst & 0x700) != 0x700)   /* entry */
                  || (inst & 0xff80) == 0x6380   /* addiu sp,-n */
                  || (inst & 0xff80) == 0xfb80   /* daddiu sp,-n */
                  || ((inst & 0xf810) == 0xf010 && seen_adjsp))  /* extend -n */
           break;
         else if ((inst & 0xff00) == 0x6300      /* addiu sp */
                  || (inst & 0xff00) == 0xfb00)  /* daddiu sp */
           seen_adjsp = 1;
         else
           seen_adjsp = 0;
       }
+    else if (mips_pc_is_micromips (gdbarch, start_pc))
+      {
+        ULONGEST insn;
+        int stop = 0;
+        long offset;
+        int dreg;
+        int sreg;
+
+        /* On microMIPS, any one of the following is likely to be the
+           start of a function:
+           ADDIUSP -imm
+           (D)ADDIU $sp, -imm
+           LUI $gp, imm  */
+        insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, NULL);
+        switch (micromips_op (insn))
+          {
+          case 0xc: /* ADDIU: bits 001100 */
+          case 0x17: /* DADDIU: bits 010111 */
+            sreg = b0s5_reg (insn);
+            dreg = b5s5_reg (insn);
+            insn <<= 16;
+            insn |= mips_fetch_instruction (gdbarch, ISA_MICROMIPS,
+                                            pc + MIPS_INSN16_SIZE, NULL);
+            offset = (b0s16_imm (insn) ^ 0x8000) - 0x8000;
+            if (sreg == MIPS_SP_REGNUM && dreg == MIPS_SP_REGNUM
+                                /* (D)ADDIU $sp, imm */
+                && offset < 0)
+              stop = 1;
+            break;
+
+          case 0x10: /* POOL32I: bits 010000 */
+            if (b5s5_op (insn) == 0xd
+                                /* LUI: bits 010000 001101 */
+                && b0s5_reg (insn >> 16) == 28)
+                                /* LUI $gp, imm */
+              stop = 1;
+            break;
+
+          case 0x13: /* POOL16D: bits 010011 */
+            if ((insn & 0x1) == 0x1)
+                                /* ADDIUSP: bits 010011 1 */
+              {
+                offset = micromips_decode_imm9 (b1s9_imm (insn));
+                if (offset < 0)
+                                /* ADDIUSP -imm */
+                  stop = 1;
+              }
+            else
+                                /* ADDIUS5: bits 010011 0 */
+              {
+                dreg = b5s5_reg (insn);
+                offset = (b1s4_imm (insn) ^ 8) - 8;
+                if (dreg == MIPS_SP_REGNUM && offset < 0)
+                                /* ADDIUS5  $sp, -imm */
+                  stop = 1;
+              }
+            break;
+          }
+        if (stop)
+          break;
+      }
     else if (mips_about_to_return (gdbarch, start_pc))
       {
         /* Skip return and its delay slot.  */
         start_pc += 2 * MIPS_INSN32_SIZE;
         break;
       }
 
   return start_pc;
 }
 
@@ skipping 53 matching lines @@
 }
 
 /* Adjust the address downward (direction of stack growth) so that it
    is correctly aligned for a new stack frame.  */
 static CORE_ADDR
 mips_frame_align (struct gdbarch *gdbarch, CORE_ADDR addr)
 {
   return align_down (addr, 16);
 }
 
+/* Implement the "push_dummy_code" gdbarch method.  */
+
+static CORE_ADDR
+mips_push_dummy_code (struct gdbarch *gdbarch, CORE_ADDR sp,
+                      CORE_ADDR funaddr, struct value **args,
+                      int nargs, struct type *value_type,
+                      CORE_ADDR *real_pc, CORE_ADDR *bp_addr,
+                      struct regcache *regcache)
+{
+  static gdb_byte nop_insn[] = { 0, 0, 0, 0 };
+  CORE_ADDR nop_addr;
+  CORE_ADDR bp_slot;
+
+  /* Reserve enough room on the stack for our breakpoint instruction.  */
+  bp_slot = sp - sizeof (nop_insn);
+
+  /* Return to microMIPS mode if calling microMIPS code to avoid
+     triggering an address error exception on processors that only
+     support microMIPS execution.  */
+  *bp_addr = (mips_pc_is_micromips (gdbarch, funaddr)
+              ? make_compact_addr (bp_slot) : bp_slot);
+
+  /* The breakpoint layer automatically adjusts the address of
+     breakpoints inserted in a branch delay slot.  With enough
+     bad luck, the 4 bytes located just before our breakpoint
+     instruction could look like a branch instruction, and thus
+     trigger the adjustement, and break the function call entirely.
+     So, we reserve those 4 bytes and write a nop instruction
+     to prevent that from happening.  */
+  nop_addr = bp_slot - sizeof (nop_insn);
+  write_memory (nop_addr, nop_insn, sizeof (nop_insn));
+  sp = mips_frame_align (gdbarch, nop_addr);
+
+  /* Inferior resumes at the function entry point.  */
+  *real_pc = funaddr;
+
+  return sp;
+}
+
 static CORE_ADDR
 mips_eabi_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
                            struct regcache *regcache, CORE_ADDR bp_addr,
                            int nargs, struct value **args, CORE_ADDR sp,
                            int struct_return, CORE_ADDR struct_addr)
 {
   int argreg;
   int float_argreg;
   int argnum;
   int len = 0;
   int stack_offset = 0;
-  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   CORE_ADDR func_addr = find_function_addr (function, NULL);
   int regsize = mips_abi_regsize (gdbarch);
 
   /* For shared libraries, "t9" needs to point at the function
      address.  */
   regcache_cooked_write_signed (regcache, MIPS_T9_REGNUM, func_addr);
 
   /* Set the return address register to point to the entry point of
      the program, where a breakpoint lies in wait.  */
@@ skipping 52 matching lines @@
                             "mips_eabi_push_dummy_call: %d len=%d type=%d",
                             argnum + 1, len, (int) typecode);
 
       /* Function pointer arguments to mips16 code need to be made into
          mips16 pointers.  */
       if (typecode == TYPE_CODE_PTR
           && TYPE_CODE (TYPE_TARGET_TYPE (arg_type)) == TYPE_CODE_FUNC)
         {
           CORE_ADDR addr = extract_signed_integer (value_contents (arg),
                                                    len, byte_order);
-          if (mips_pc_is_mips16 (addr))
+          if (mips_pc_is_mips (addr))
+            val = value_contents (arg);
+          else
             {
               store_signed_integer (valbuf, len, byte_order, 
-                                    make_mips16_addr (addr));
+                                    make_compact_addr (addr));
               val = valbuf;
             }
-          else
-            val = value_contents (arg);
         }
       /* The EABI passes structures that do not fit in a register by
          reference.  */
       else if (len > regsize
           && (typecode == TYPE_CODE_STRUCT || typecode == TYPE_CODE_UNION))
         {
           store_unsigned_integer (valbuf, regsize, byte_order,
                                   value_address (arg));
           typecode = TYPE_CODE_PTR;
           len = regsize;
@@ skipping 179 matching lines @@
 
   regcache_cooked_write_signed (regcache, MIPS_SP_REGNUM, sp);
 
   /* Return adjusted stack pointer.  */
   return sp;
 }
 
 /* Determine the return value convention being used.  */
 
 static enum return_value_convention
-mips_eabi_return_value (struct gdbarch *gdbarch, struct type *func_type,
+mips_eabi_return_value (struct gdbarch *gdbarch, struct value *function,
                         struct type *type, struct regcache *regcache,
                         gdb_byte *readbuf, const gdb_byte *writebuf)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   int fp_return_type = 0;
   int offset, regnum, xfer;
 
   if (TYPE_LENGTH (type) > 2 * mips_abi_regsize (gdbarch))
     return RETURN_VALUE_STRUCT_CONVENTION;
 
@@ skipping 107 matching lines @@
 mips_n32n64_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
                              struct regcache *regcache, CORE_ADDR bp_addr,
                              int nargs, struct value **args, CORE_ADDR sp,
                              int struct_return, CORE_ADDR struct_addr)
 {
   int argreg;
   int float_argreg;
   int argnum;
   int len = 0;
   int stack_offset = 0;
-  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   CORE_ADDR func_addr = find_function_addr (function, NULL);
 
   /* For shared libraries, "t9" needs to point at the function
      address.  */
   regcache_cooked_write_signed (regcache, MIPS_T9_REGNUM, func_addr);
 
   /* Set the return address register to point to the entry point of
      the program, where a breakpoint lies in wait.  */
   regcache_cooked_write_signed (regcache, MIPS_RA_REGNUM, bp_addr);
@@ skipping 241 matching lines @@
         fprintf_unfiltered (gdb_stdlog, "\n");
     }
 
   regcache_cooked_write_signed (regcache, MIPS_SP_REGNUM, sp);
 
   /* Return adjusted stack pointer.  */
   return sp;
 }
 
 static enum return_value_convention
-mips_n32n64_return_value (struct gdbarch *gdbarch, struct type *func_type,
+mips_n32n64_return_value (struct gdbarch *gdbarch, struct value *function,
                           struct type *type, struct regcache *regcache,
                           gdb_byte *readbuf, const gdb_byte *writebuf)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
 
   /* From MIPSpro N32 ABI Handbook, Document Number: 007-2816-004
 
      Function results are returned in $2 (and $3 if needed), or $f0 (and $f2
      if needed), as appropriate for the type.  Composite results (struct,
      union, or array) are returned in $2/$f0 and $3/$f2 according to the
@@ skipping 19 matching lines @@
   else if (TYPE_CODE (type) == TYPE_CODE_FLT
            && TYPE_LENGTH (type) == 16
            && tdep->mips_fpu_type != MIPS_FPU_NONE)
     {
       /* A 128-bit floating-point value fills both $f0 and $f2.  The
          two registers are used in the same as memory order, so the
          eight bytes with the lower memory address are in $f0.  */
       if (mips_debug)
         fprintf_unfiltered (gdb_stderr, "Return float in $f0 and $f2\n");
       mips_xfer_register (gdbarch, regcache,
-                          gdbarch_num_regs (gdbarch)
-                          + mips_regnum (gdbarch)->fp0,
+                          (gdbarch_num_regs (gdbarch)
+                           + mips_regnum (gdbarch)->fp0),
                           8, gdbarch_byte_order (gdbarch),
                           readbuf, writebuf, 0);
       mips_xfer_register (gdbarch, regcache,
-                          gdbarch_num_regs (gdbarch)
-                          + mips_regnum (gdbarch)->fp0 + 2,
+                          (gdbarch_num_regs (gdbarch)
+                           + mips_regnum (gdbarch)->fp0 + 2),
                           8, gdbarch_byte_order (gdbarch),
                           readbuf ? readbuf + 8 : readbuf,
                           writebuf ? writebuf + 8 : writebuf, 0);
       return RETURN_VALUE_REGISTER_CONVENTION;
     }
   else if (TYPE_CODE (type) == TYPE_CODE_FLT
            && tdep->mips_fpu_type != MIPS_FPU_NONE)
     {
       /* A single or double floating-point value that fits in FP0.  */
       if (mips_debug)
         fprintf_unfiltered (gdb_stderr, "Return float in $fp0\n");
       mips_xfer_register (gdbarch, regcache,
-                          gdbarch_num_regs (gdbarch)
-                          + mips_regnum (gdbarch)->fp0,
+                          (gdbarch_num_regs (gdbarch)
+                           + mips_regnum (gdbarch)->fp0),
                           TYPE_LENGTH (type),
                           gdbarch_byte_order (gdbarch),
                           readbuf, writebuf, 0);
       return RETURN_VALUE_REGISTER_CONVENTION;
     }
   else if (TYPE_CODE (type) == TYPE_CODE_STRUCT
            && TYPE_NFIELDS (type) <= 2
            && TYPE_NFIELDS (type) >= 1
            && ((TYPE_NFIELDS (type) == 1
                 && (TYPE_CODE (check_typedef (TYPE_FIELD_TYPE (type, 0)))
@@ skipping 87 matching lines @@
                                 offset, xfer, regnum);
           mips_xfer_register (gdbarch, regcache,
                               gdbarch_num_regs (gdbarch) + regnum,
                               xfer, gdbarch_byte_order (gdbarch),
                               readbuf, writebuf, offset);
         }
       return RETURN_VALUE_REGISTER_CONVENTION;
     }
 }
 
+/* Which registers to use for passing floating-point values between
+   function calls, one of floating-point, general and both kinds of
+   registers.  O32 and O64 use different register kinds for standard
+   MIPS and MIPS16 code; to make the handling of cases where we may
+   not know what kind of code is being used (e.g. no debug information)
+   easier we sometimes use both kinds.  */
+
+enum mips_fval_reg
+{
+  mips_fval_fpr,
+  mips_fval_gpr,
+  mips_fval_both
+};
+
 /* O32 ABI stuff.  */
 
 static CORE_ADDR
 mips_o32_push_dummy_call (struct gdbarch *gdbarch, struct value *function,
                           struct regcache *regcache, CORE_ADDR bp_addr,
                           int nargs, struct value **args, CORE_ADDR sp,
                           int struct_return, CORE_ADDR struct_addr)
 {
   int argreg;
   int float_argreg;
   int argnum;
   int len = 0;
   int stack_offset = 0;
-  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   CORE_ADDR func_addr = find_function_addr (function, NULL);
 
   /* For shared libraries, "t9" needs to point at the function
      address.  */
   regcache_cooked_write_signed (regcache, MIPS_T9_REGNUM, func_addr);
 
   /* Set the return address register to point to the entry point of
      the program, where a breakpoint lies in wait.  */
   regcache_cooked_write_signed (regcache, MIPS_RA_REGNUM, bp_addr);
@@ skipping 56 matching lines @@
       if (mips_debug)
         fprintf_unfiltered (gdb_stdlog,
                             "mips_o32_push_dummy_call: %d len=%d type=%d",
                             argnum + 1, len, (int) typecode);
 
       val = value_contents (arg);
 
       /* 32-bit ABIs always start floating point arguments in an
          even-numbered floating point register.  Round the FP register
          up before the check to see if there are any FP registers
-         left.  O32/O64 targets also pass the FP in the integer
-         registers so also round up normal registers.  */
+         left.  O32 targets also pass the FP in the integer registers
+         so also round up normal registers.  */
       if (fp_register_arg_p (gdbarch, typecode, arg_type))
         {
           if ((float_argreg & 1))
             float_argreg++;
         }
 
       /* Floating point arguments passed in registers have to be
-         treated specially.  On 32-bit architectures, doubles
-         are passed in register pairs; the even register gets
-         the low word, and the odd register gets the high word.
-         On O32/O64, the first two floating point arguments are
-         also copied to general registers, because MIPS16 functions
-         don't use float registers for arguments.  This duplication of
-         arguments in general registers can't hurt non-MIPS16 functions
-         because those registers are normally skipped.  */
+         treated specially.  On 32-bit architectures, doubles are
+         passed in register pairs; the even FP register gets the
+         low word, and the odd FP register gets the high word.
+         On O32, the first two floating point arguments are also
+         copied to general registers, following their memory order,
+         because MIPS16 functions don't use float registers for
+         arguments.  This duplication of arguments in general
+         registers can't hurt non-MIPS16 functions, because those
+         registers are normally skipped.  */
 
       if (fp_register_arg_p (gdbarch, typecode, arg_type)
           && float_argreg <= MIPS_LAST_FP_ARG_REGNUM (gdbarch))
         {
           if (register_size (gdbarch, float_argreg) < 8 && len == 8)
             {
-              int low_offset = gdbarch_byte_order (gdbarch)
-                               == BFD_ENDIAN_BIG ? 4 : 0;
+              int freg_offset = gdbarch_byte_order (gdbarch)
+                                == BFD_ENDIAN_BIG ? 1 : 0;
               unsigned long regval;
 
-              /* Write the low word of the double to the even register(s).  */
-              regval = extract_unsigned_integer (val + low_offset,
-                                                 4, byte_order);
+              /* First word.  */
+              regval = extract_unsigned_integer (val, 4, byte_order);
               if (mips_debug)
                 fprintf_unfiltered (gdb_stdlog, " - fpreg=%d val=%s",
-                                    float_argreg, phex (regval, 4));
+                                    float_argreg + freg_offset,
+                                    phex (regval, 4));
               regcache_cooked_write_unsigned (regcache,
-                                              float_argreg++, regval);
+                                              float_argreg++ + freg_offset,
+                                              regval);
               if (mips_debug)
                 fprintf_unfiltered (gdb_stdlog, " - reg=%d val=%s",
                                     argreg, phex (regval, 4));
               regcache_cooked_write_unsigned (regcache, argreg++, regval);
 
-              /* Write the high word of the double to the odd register(s).  */
-              regval = extract_unsigned_integer (val + 4 - low_offset,
-                                                 4, byte_order);
+              /* Second word.  */
+              regval = extract_unsigned_integer (val + 4, 4, byte_order);
               if (mips_debug)
                 fprintf_unfiltered (gdb_stdlog, " - fpreg=%d val=%s",
-                                    float_argreg, phex (regval, 4));
+                                    float_argreg - freg_offset,
+                                    phex (regval, 4));
               regcache_cooked_write_unsigned (regcache,
-                                              float_argreg++, regval);
-
+                                              float_argreg++ - freg_offset,
+                                              regval);
               if (mips_debug)
                 fprintf_unfiltered (gdb_stdlog, " - reg=%d val=%s",
                                     argreg, phex (regval, 4));
               regcache_cooked_write_unsigned (regcache, argreg++, regval);
             }
           else
             {
               /* This is a floating point value that fits entirely
                  in a single register.  */
               /* On 32 bit ABI's the float_argreg is further adjusted
@@ skipping 154 matching lines @@
         fprintf_unfiltered (gdb_stdlog, "\n");
     }
 
   regcache_cooked_write_signed (regcache, MIPS_SP_REGNUM, sp);
 
   /* Return adjusted stack pointer.  */
   return sp;
 }
 
 static enum return_value_convention
-mips_o32_return_value (struct gdbarch *gdbarch, struct type *func_type,
+mips_o32_return_value (struct gdbarch *gdbarch, struct value *function,
                        struct type *type, struct regcache *regcache,
                        gdb_byte *readbuf, const gdb_byte *writebuf)
 {
+  CORE_ADDR func_addr = function ? find_function_addr (function, NULL) : 0;
+  int mips16 = mips_pc_is_mips16 (gdbarch, func_addr);
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+  enum mips_fval_reg fval_reg;
 
+  fval_reg = readbuf ? mips16 ? mips_fval_gpr : mips_fval_fpr : mips_fval_both;
   if (TYPE_CODE (type) == TYPE_CODE_STRUCT
       || TYPE_CODE (type) == TYPE_CODE_UNION
       || TYPE_CODE (type) == TYPE_CODE_ARRAY)
     return RETURN_VALUE_STRUCT_CONVENTION;
   else if (TYPE_CODE (type) == TYPE_CODE_FLT
            && TYPE_LENGTH (type) == 4 && tdep->mips_fpu_type != MIPS_FPU_NONE)
     {
-      /* A single-precision floating-point value.  It fits in the
-         least significant part of FP0.  */
+      /* A single-precision floating-point value.  If reading in or copying,
+         then we get it from/put it to FP0 for standard MIPS code or GPR2
+         for MIPS16 code.  If writing out only, then we put it to both FP0
+         and GPR2.  We do not support reading in with no function known, if
+         this safety check ever triggers, then we'll have to try harder.  */
+      gdb_assert (function || !readbuf);
       if (mips_debug)
-        fprintf_unfiltered (gdb_stderr, "Return float in $fp0\n");
-      mips_xfer_register (gdbarch, regcache,
-                          gdbarch_num_regs (gdbarch)
-                            + mips_regnum (gdbarch)->fp0,
-                          TYPE_LENGTH (type),
-                          gdbarch_byte_order (gdbarch),
-                          readbuf, writebuf, 0);
+        switch (fval_reg)
+          {
+          case mips_fval_fpr:
+            fprintf_unfiltered (gdb_stderr, "Return float in $fp0\n");
+            break;
+          case mips_fval_gpr:
+            fprintf_unfiltered (gdb_stderr, "Return float in $2\n");
+            break;
+          case mips_fval_both:
+            fprintf_unfiltered (gdb_stderr, "Return float in $fp0 and $2\n");
+            break;
+          }
+      if (fval_reg != mips_fval_gpr)
+        mips_xfer_register (gdbarch, regcache,
+                            (gdbarch_num_regs (gdbarch)
+                             + mips_regnum (gdbarch)->fp0),
+                            TYPE_LENGTH (type),
+                            gdbarch_byte_order (gdbarch),
+                            readbuf, writebuf, 0);
+      if (fval_reg != mips_fval_fpr)
+        mips_xfer_register (gdbarch, regcache,
+                            gdbarch_num_regs (gdbarch) + 2,
+                            TYPE_LENGTH (type),
+                            gdbarch_byte_order (gdbarch),
+                            readbuf, writebuf, 0);
       return RETURN_VALUE_REGISTER_CONVENTION;
     }
   else if (TYPE_CODE (type) == TYPE_CODE_FLT
            && TYPE_LENGTH (type) == 8 && tdep->mips_fpu_type != MIPS_FPU_NONE)
     {
-      /* A double-precision floating-point value.  The most
-         significant part goes in FP1, and the least significant in
-         FP0.  */
+      /* A double-precision floating-point value.  If reading in or copying,
+         then we get it from/put it to FP1 and FP0 for standard MIPS code or
+         GPR2 and GPR3 for MIPS16 code.  If writing out only, then we put it
+         to both FP1/FP0 and GPR2/GPR3.  We do not support reading in with
+         no function known, if this safety check ever triggers, then we'll
+         have to try harder.  */
+      gdb_assert (function || !readbuf);
       if (mips_debug)
-        fprintf_unfiltered (gdb_stderr, "Return float in $fp1/$fp0\n");
-      switch (gdbarch_byte_order (gdbarch))
+        switch (fval_reg)
+          {
+          case mips_fval_fpr:
+            fprintf_unfiltered (gdb_stderr, "Return float in $fp1/$fp0\n");
+            break;
+          case mips_fval_gpr:
+            fprintf_unfiltered (gdb_stderr, "Return float in $2/$3\n");
+            break;
+          case mips_fval_both:
+            fprintf_unfiltered (gdb_stderr,
+                                "Return float in $fp1/$fp0 and $2/$3\n");
+            break;
+          }
+      if (fval_reg != mips_fval_gpr)
         {
-        case BFD_ENDIAN_LITTLE:
+          /* The most significant part goes in FP1, and the least significant
+             in FP0.  */
+          switch (gdbarch_byte_order (gdbarch))
+            {
+            case BFD_ENDIAN_LITTLE:
+              mips_xfer_register (gdbarch, regcache,
+                                  (gdbarch_num_regs (gdbarch)
+                                   + mips_regnum (gdbarch)->fp0 + 0),
+                                  4, gdbarch_byte_order (gdbarch),
+                                  readbuf, writebuf, 0);
+              mips_xfer_register (gdbarch, regcache,
+                                  (gdbarch_num_regs (gdbarch)
+                                   + mips_regnum (gdbarch)->fp0 + 1),
+                                  4, gdbarch_byte_order (gdbarch),
+                                  readbuf, writebuf, 4);
+              break;
+            case BFD_ENDIAN_BIG:
+              mips_xfer_register (gdbarch, regcache,
+                                  (gdbarch_num_regs (gdbarch)
+                                   + mips_regnum (gdbarch)->fp0 + 1),
+                                  4, gdbarch_byte_order (gdbarch),
+                                  readbuf, writebuf, 0);
+              mips_xfer_register (gdbarch, regcache,
+                                  (gdbarch_num_regs (gdbarch)
+                                   + mips_regnum (gdbarch)->fp0 + 0),
+                                  4, gdbarch_byte_order (gdbarch),
+                                  readbuf, writebuf, 4);
+              break;
+            default:
+              internal_error (__FILE__, __LINE__, _("bad switch"));
+            }
+        }
+      if (fval_reg != mips_fval_fpr)
+        {
+          /* The two 32-bit parts are always placed in GPR2 and GPR3
+             following these registers' memory order.  */
           mips_xfer_register (gdbarch, regcache,
-                              gdbarch_num_regs (gdbarch)
-                                + mips_regnum (gdbarch)->fp0 +
-                              0, 4, gdbarch_byte_order (gdbarch),
-                              readbuf, writebuf, 0);
-          mips_xfer_register (gdbarch, regcache,
-                              gdbarch_num_regs (gdbarch)
-                                + mips_regnum (gdbarch)->fp0 + 1,
-                              4, gdbarch_byte_order (gdbarch),
-                              readbuf, writebuf, 4);
-          break;
-        case BFD_ENDIAN_BIG:
-          mips_xfer_register (gdbarch, regcache,
-                              gdbarch_num_regs (gdbarch)
-                                + mips_regnum (gdbarch)->fp0 + 1,
+                              gdbarch_num_regs (gdbarch) + 2,
                               4, gdbarch_byte_order (gdbarch),
                               readbuf, writebuf, 0);
           mips_xfer_register (gdbarch, regcache,
-                              gdbarch_num_regs (gdbarch)
-                                + mips_regnum (gdbarch)->fp0 + 0,
+                              gdbarch_num_regs (gdbarch) + 3,
                               4, gdbarch_byte_order (gdbarch),
                               readbuf, writebuf, 4);
-          break;
-        default:
-          internal_error (__FILE__, __LINE__, _("bad switch"));
         }
       return RETURN_VALUE_REGISTER_CONVENTION;
     }
 #if 0
   else if (TYPE_CODE (type) == TYPE_CODE_STRUCT
            && TYPE_NFIELDS (type) <= 2
            && TYPE_NFIELDS (type) >= 1
            && ((TYPE_NFIELDS (type) == 1
                 && (TYPE_CODE (TYPE_FIELD_TYPE (type, 0))
                     == TYPE_CODE_FLT))
@@ skipping 87 matching lines @@
                           struct regcache *regcache, CORE_ADDR bp_addr,
                           int nargs,
                           struct value **args, CORE_ADDR sp,
                           int struct_return, CORE_ADDR struct_addr)
 {
   int argreg;
   int float_argreg;
   int argnum;
   int len = 0;
   int stack_offset = 0;
-  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   CORE_ADDR func_addr = find_function_addr (function, NULL);
 
   /* For shared libraries, "t9" needs to point at the function
      address.  */
   regcache_cooked_write_signed (regcache, MIPS_T9_REGNUM, func_addr);
 
   /* Set the return address register to point to the entry point of
      the program, where a breakpoint lies in wait.  */
   regcache_cooked_write_signed (regcache, MIPS_RA_REGNUM, bp_addr);
@@ skipping 58 matching lines @@
 
       val = value_contents (arg);
 
       /* Function pointer arguments to mips16 code need to be made into
          mips16 pointers.  */
       if (typecode == TYPE_CODE_PTR
           && TYPE_CODE (TYPE_TARGET_TYPE (arg_type)) == TYPE_CODE_FUNC)
         {
           CORE_ADDR addr = extract_signed_integer (value_contents (arg),
                                                    len, byte_order);
-          if (mips_pc_is_mips16 (addr))
+          if (!mips_pc_is_mips (addr))
             {
               store_signed_integer (valbuf, len, byte_order, 
-                                    make_mips16_addr (addr));
+                                    make_compact_addr (addr));
               val = valbuf;
             }
         }
 
       /* Floating point arguments passed in registers have to be
-         treated specially.  On 32-bit architectures, doubles
-         are passed in register pairs; the even register gets
-         the low word, and the odd register gets the high word.
-         On O32/O64, the first two floating point arguments are
-         also copied to general registers, because MIPS16 functions
-         don't use float registers for arguments.  This duplication of
-         arguments in general registers can't hurt non-MIPS16 functions
-         because those registers are normally skipped.  */
+         treated specially.  On 32-bit architectures, doubles are
+         passed in register pairs; the even FP register gets the
+         low word, and the odd FP register gets the high word.
+         On O64, the first two floating point arguments are also
+         copied to general registers, because MIPS16 functions
+         don't use float registers for arguments.  This duplication
+         of arguments in general registers can't hurt non-MIPS16
+         functions because those registers are normally skipped.  */
 
       if (fp_register_arg_p (gdbarch, typecode, arg_type)
           && float_argreg <= MIPS_LAST_FP_ARG_REGNUM (gdbarch))
         {
           LONGEST regval = extract_unsigned_integer (val, len, byte_order);
           if (mips_debug)
             fprintf_unfiltered (gdb_stdlog, " - fpreg=%d val=%s",
                                 float_argreg, phex (regval, len));
           regcache_cooked_write_unsigned (regcache, float_argreg++, regval);
           if (mips_debug)
@@ skipping 124 matching lines @@
         fprintf_unfiltered (gdb_stdlog, "\n");
     }
 
   regcache_cooked_write_signed (regcache, MIPS_SP_REGNUM, sp);
 
   /* Return adjusted stack pointer.  */
   return sp;
 }
 
 static enum return_value_convention
-mips_o64_return_value (struct gdbarch *gdbarch, struct type *func_type,
+mips_o64_return_value (struct gdbarch *gdbarch, struct value *function,
                        struct type *type, struct regcache *regcache,
                        gdb_byte *readbuf, const gdb_byte *writebuf)
 {
+  CORE_ADDR func_addr = function ? find_function_addr (function, NULL) : 0;
+  int mips16 = mips_pc_is_mips16 (gdbarch, func_addr);
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+  enum mips_fval_reg fval_reg;
 
+  fval_reg = readbuf ? mips16 ? mips_fval_gpr : mips_fval_fpr : mips_fval_both;
   if (TYPE_CODE (type) == TYPE_CODE_STRUCT
       || TYPE_CODE (type) == TYPE_CODE_UNION
       || TYPE_CODE (type) == TYPE_CODE_ARRAY)
     return RETURN_VALUE_STRUCT_CONVENTION;
   else if (fp_register_arg_p (gdbarch, TYPE_CODE (type), type))
     {
-      /* A floating-point value.  It fits in the least significant
-         part of FP0.  */
+      /* A floating-point value.  If reading in or copying, then we get it
+         from/put it to FP0 for standard MIPS code or GPR2 for MIPS16 code.
+         If writing out only, then we put it to both FP0 and GPR2.  We do
+         not support reading in with no function known, if this safety
+         check ever triggers, then we'll have to try harder.  */
+      gdb_assert (function || !readbuf);
       if (mips_debug)
-        fprintf_unfiltered (gdb_stderr, "Return float in $fp0\n");
-      mips_xfer_register (gdbarch, regcache,
-                          gdbarch_num_regs (gdbarch)
-                            + mips_regnum (gdbarch)->fp0,
-                          TYPE_LENGTH (type),
-                          gdbarch_byte_order (gdbarch),
-                          readbuf, writebuf, 0);
+        switch (fval_reg)
+          {
+          case mips_fval_fpr:
+            fprintf_unfiltered (gdb_stderr, "Return float in $fp0\n");
+            break;
+          case mips_fval_gpr:
+            fprintf_unfiltered (gdb_stderr, "Return float in $2\n");
+            break;
+          case mips_fval_both:
+            fprintf_unfiltered (gdb_stderr, "Return float in $fp0 and $2\n");
+            break;
+          }
+      if (fval_reg != mips_fval_gpr)
+        mips_xfer_register (gdbarch, regcache,
+                            (gdbarch_num_regs (gdbarch)
+                             + mips_regnum (gdbarch)->fp0),
+                            TYPE_LENGTH (type),
+                            gdbarch_byte_order (gdbarch),
+                            readbuf, writebuf, 0);
+      if (fval_reg != mips_fval_fpr)
+        mips_xfer_register (gdbarch, regcache,
+                            gdbarch_num_regs (gdbarch) + 2,
+                            TYPE_LENGTH (type),
+                            gdbarch_byte_order (gdbarch),
+                            readbuf, writebuf, 0);
       return RETURN_VALUE_REGISTER_CONVENTION;
     }
   else
     {
       /* A scalar extract each part but least-significant-byte
          justified.  */
       int offset;
       int regnum;
       for (offset = 0, regnum = MIPS_V0_REGNUM;
            offset < TYPE_LENGTH (type);
@@ skipping 201 matching lines @@
       else
         fprintf_filtered (file, "%-24.17g", doub);
     }
 }
 
 static void
 mips_print_register (struct ui_file *file, struct frame_info *frame,
                      int regnum)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
-  int offset;
   struct value_print_options opts;
   struct value *val;
 
-  if (TYPE_CODE (register_type (gdbarch, regnum)) == TYPE_CODE_FLT)
+  if (mips_float_register_p (gdbarch, regnum))
     {
       mips_print_fp_register (file, frame, regnum);
       return;
     }
 
   val = get_frame_register_value (frame, regnum);
   if (value_optimized_out (val))
     {
       fprintf_filtered (file, "%s: [Invalid]",
                         gdbarch_register_name (gdbarch, regnum));
@@ skipping 48 matching lines @@
   int regnum;
 
   /* For GP registers, we print a separate row of names above the vals.  */
   for (col = 0, regnum = start_regnum;
        col < ncols && regnum < gdbarch_num_regs (gdbarch)
                                + gdbarch_num_pseudo_regs (gdbarch);
        regnum++)
     {
       if (*gdbarch_register_name (gdbarch, regnum) == '\0')
         continue;               /* unused register */
-      if (TYPE_CODE (register_type (gdbarch, regnum)) ==
-          TYPE_CODE_FLT)
+      if (mips_float_register_p (gdbarch, regnum))
         break;                  /* End the row: reached FP register.  */
       /* Large registers are handled separately.  */
       if (register_size (gdbarch, regnum) > mips_abi_regsize (gdbarch))
         {
           if (col > 0)
             break;              /* End the row before this register.  */
 
           /* Print this register on a row by itself.  */
           mips_print_register (file, frame, regnum);
           fprintf_filtered (file, "\n");
@@ skipping 18 matching lines @@
     fprintf_filtered (file, "\n      ");
 
   /* Now print the values in hex, 4 or 8 to the row.  */
   for (col = 0, regnum = start_regnum;
        col < ncols && regnum < gdbarch_num_regs (gdbarch)
                                + gdbarch_num_pseudo_regs (gdbarch);
        regnum++)
     {
       if (*gdbarch_register_name (gdbarch, regnum) == '\0')
         continue;               /* unused register */
-      if (TYPE_CODE (register_type (gdbarch, regnum)) ==
-          TYPE_CODE_FLT)
+      if (mips_float_register_p (gdbarch, regnum))
         break;                  /* End row: reached FP register.  */
       if (register_size (gdbarch, regnum) > mips_abi_regsize (gdbarch))
         break;                  /* End row: large register.  */
 
       /* OK: get the data in raw format.  */
       if (!frame_register_read (frame, regnum, raw_buffer))
         error (_("can't read register %d (%s)"),
                regnum, gdbarch_register_name (gdbarch, regnum));
       /* pad small registers */
       for (byte = 0;
@@ skipping 34 matching lines @@
       mips_print_register (file, frame, regnum);
       fprintf_filtered (file, "\n");
     }
   else
     /* Do all (or most) registers.  */
     {
       regnum = gdbarch_num_regs (gdbarch);
       while (regnum < gdbarch_num_regs (gdbarch)
                       + gdbarch_num_pseudo_regs (gdbarch))
         {
-          if (TYPE_CODE (register_type (gdbarch, regnum)) ==
-              TYPE_CODE_FLT)
+          if (mips_float_register_p (gdbarch, regnum))
             {
               if (all)          /* True for "INFO ALL-REGISTERS" command.  */
                 regnum = print_fp_register_row (file, frame, regnum);
               else
                 regnum += MIPS_NUMREGS; /* Skip floating point regs.  */
             }
           else
             regnum = print_gp_register_row (file, frame, regnum);
         }
     }
 }
 
-/* Is this a branch with a delay slot?  */
-
-static int
-is_delayed (unsigned long insn)
-{
-  int i;
-  for (i = 0; i < NUMOPCODES; ++i)
-    if (mips_opcodes[i].pinfo != INSN_MACRO
-        && (insn & mips_opcodes[i].mask) == mips_opcodes[i].match)
-      break;
-  return (i < NUMOPCODES
-          && (mips_opcodes[i].pinfo & (INSN_UNCOND_BRANCH_DELAY
-                                       | INSN_COND_BRANCH_DELAY
-                                       | INSN_COND_BRANCH_LIKELY)));
-}
-
 static int
 mips_single_step_through_delay (struct gdbarch *gdbarch,
                                 struct frame_info *frame)
 {
   enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
   CORE_ADDR pc = get_frame_pc (frame);
-  gdb_byte buf[MIPS_INSN32_SIZE];
+  struct address_space *aspace;
+  enum mips_isa isa;
+  ULONGEST insn;
+  int status;
+  int size;
 
-  /* There is no branch delay slot on MIPS16.  */
-  if (mips_pc_is_mips16 (pc))
+  if ((mips_pc_is_mips (pc)
+       && !mips32_instruction_has_delay_slot (gdbarch, pc))
+      || (mips_pc_is_micromips (gdbarch, pc)
+          && !micromips_instruction_has_delay_slot (gdbarch, pc, 0))
+      || (mips_pc_is_mips16 (gdbarch, pc)
+          && !mips16_instruction_has_delay_slot (gdbarch, pc, 0)))
     return 0;
 
-  if (!breakpoint_here_p (get_frame_address_space (frame), pc + 4))
-    return 0;
-
-  if (!safe_frame_unwind_memory (frame, pc, buf, sizeof buf))
-    /* If error reading memory, guess that it is not a delayed
-       branch.  */
-    return 0;
-  return is_delayed (extract_unsigned_integer (buf, sizeof buf, byte_order));
+  isa = mips_pc_isa (gdbarch, pc);
+  /* _has_delay_slot above will have validated the read.  */
+  insn = mips_fetch_instruction (gdbarch, isa, pc, NULL);
+  size = mips_insn_size (isa, insn);
+  aspace = get_frame_address_space (frame);
+  return breakpoint_here_p (aspace, pc + size) != no_breakpoint_here;
 }
 
 /* To skip prologues, I use this predicate.  Returns either PC itself
    if the code at PC does not look like a function prologue; otherwise
    returns an address that (if we're lucky) follows the prologue.  If
    LENIENT, then we must skip everything which is involved in setting
    up the frame (it's OK to skip more, just so long as we don't skip
    anything which might clobber the registers which are being saved.
    We must skip more in the case where part of the prologue is in the
    delay slot of a non-prologue instruction).  */
@@ skipping 18 matching lines @@
   /* Can't determine prologue from the symbol table, need to examine
      instructions.  */
 
   /* Find an upper limit on the function prologue using the debug
      information.  If the debug information could not be used to provide
      that bound, then use an arbitrary large number as the upper bound.  */
   limit_pc = skip_prologue_using_sal (gdbarch, pc);
   if (limit_pc == 0)
     limit_pc = pc + 100;          /* Magic.  */
 
-  if (mips_pc_is_mips16 (pc))
+  if (mips_pc_is_mips16 (gdbarch, pc))
     return mips16_scan_prologue (gdbarch, pc, limit_pc, NULL, NULL);
+  else if (mips_pc_is_micromips (gdbarch, pc))
+    return micromips_scan_prologue (gdbarch, pc, limit_pc, NULL, NULL);
   else
     return mips32_scan_prologue (gdbarch, pc, limit_pc, NULL, NULL);
 }
 
 /* Check whether the PC is in a function epilogue (32-bit version).
    This is a helper function for mips_in_function_epilogue_p.  */
 static int
 mips32_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
 {
   CORE_ADDR func_addr = 0, func_end = 0;
 
   if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
     {
       /* The MIPS epilogue is max. 12 bytes long.  */
       CORE_ADDR addr = func_end - 12;
 
       if (addr < func_addr + 4)
         addr = func_addr + 4;
       if (pc < addr)
         return 0;
 
       for (; pc < func_end; pc += MIPS_INSN32_SIZE)
         {
           unsigned long high_word;
           unsigned long inst;
 
-          inst = mips_fetch_instruction (gdbarch, pc);
+          inst = mips_fetch_instruction (gdbarch, ISA_MIPS, pc, NULL);
           high_word = (inst >> 16) & 0xffff;
 
           if (high_word != 0x27bd       /* addiu $sp,$sp,offset */
               && high_word != 0x67bd    /* daddiu $sp,$sp,offset */
               && inst != 0x03e00008     /* jr $ra */
               && inst != 0x00000000)    /* nop */
             return 0;
         }
 
       return 1;
     }
 
   return 0;
 }
 
+/* Check whether the PC is in a function epilogue (microMIPS version).
+   This is a helper function for mips_in_function_epilogue_p.  */
+
+static int
+micromips_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
+{
+  CORE_ADDR func_addr = 0;
+  CORE_ADDR func_end = 0;
+  CORE_ADDR addr;
+  ULONGEST insn;
+  long offset;
+  int dreg;
+  int sreg;
+  int loc;
+
+  if (!find_pc_partial_function (pc, NULL, &func_addr, &func_end))
+    return 0;
+
+  /* The microMIPS epilogue is max. 12 bytes long.  */
+  addr = func_end - 12;
+
+  if (addr < func_addr + 2)
+    addr = func_addr + 2;
+  if (pc < addr)
+    return 0;
+
+  for (; pc < func_end; pc += loc)
+    {
+      loc = 0;
+      insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, NULL);
+      loc += MIPS_INSN16_SIZE;
+      switch (mips_insn_size (ISA_MICROMIPS, insn))
+        {
+        /* 48-bit instructions.  */
+        case 3 * MIPS_INSN16_SIZE:
+          /* No epilogue instructions in this category.  */
+          return 0;
+
+        /* 32-bit instructions.  */
+        case 2 * MIPS_INSN16_SIZE:
+          insn <<= 16;
+          insn |= mips_fetch_instruction (gdbarch,
+                                          ISA_MICROMIPS, pc + loc, NULL);
+          loc += MIPS_INSN16_SIZE;
+          switch (micromips_op (insn >> 16))
+            {
+            case 0xc: /* ADDIU: bits 001100 */
+            case 0x17: /* DADDIU: bits 010111 */
+              sreg = b0s5_reg (insn >> 16);
+              dreg = b5s5_reg (insn >> 16);
+              offset = (b0s16_imm (insn) ^ 0x8000) - 0x8000;
+              if (sreg == MIPS_SP_REGNUM && dreg == MIPS_SP_REGNUM
+                            /* (D)ADDIU $sp, imm */
+                  && offset >= 0)
+                break;
+              return 0;
+
+            default:
+              return 0;
+            }
+          break;
+
+        /* 16-bit instructions.  */
+        case MIPS_INSN16_SIZE:
+          switch (micromips_op (insn))
+            {
+            case 0x3: /* MOVE: bits 000011 */
+              sreg = b0s5_reg (insn);
+              dreg = b5s5_reg (insn);
+              if (sreg == 0 && dreg == 0)
+                                /* MOVE $zero, $zero aka NOP */
+                break;
+              return 0;
+
+            case 0x11: /* POOL16C: bits 010001 */
+              if (b5s5_op (insn) == 0x18
+                                /* JRADDIUSP: bits 010011 11000 */
+                  || (b5s5_op (insn) == 0xd
+                                /* JRC: bits 010011 01101 */
+                      && b0s5_reg (insn) == MIPS_RA_REGNUM))
+                                /* JRC $ra */
+                break;
+              return 0;
+
+            case 0x13: /* POOL16D: bits 010011 */
+              offset = micromips_decode_imm9 (b1s9_imm (insn));
+              if ((insn & 0x1) == 0x1
+                                /* ADDIUSP: bits 010011 1 */
+                  && offset > 0)
+                break;
+              return 0;
+
+            default:
+              return 0;
+            }
+        }
+    }
+
+  return 1;
+}
+
 /* Check whether the PC is in a function epilogue (16-bit version).
    This is a helper function for mips_in_function_epilogue_p.  */
 static int
 mips16_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
 {
   CORE_ADDR func_addr = 0, func_end = 0;
 
   if (find_pc_partial_function (pc, NULL, &func_addr, &func_end))
     {
       /* The MIPS epilogue is max. 12 bytes long.  */
       CORE_ADDR addr = func_end - 12;
 
       if (addr < func_addr + 4)
         addr = func_addr + 4;
       if (pc < addr)
         return 0;
 
       for (; pc < func_end; pc += MIPS_INSN16_SIZE)
         {
           unsigned short inst;
 
-          inst = mips_fetch_instruction (gdbarch, pc);
+          inst = mips_fetch_instruction (gdbarch, ISA_MIPS16, pc, NULL);
 
           if ((inst & 0xf800) == 0xf000)        /* extend */
             continue;
 
           if (inst != 0x6300            /* addiu $sp,offset */
               && inst != 0xfb00         /* daddiu $sp,$sp,offset */
               && inst != 0xe820         /* jr $ra */
               && inst != 0xe8a0         /* jrc $ra */
               && inst != 0x6500)        /* nop */
             return 0;
         }
 
       return 1;
     }
 
   return 0;
 }
 
 /* The epilogue is defined here as the area at the end of a function,
    after an instruction which destroys the function's stack frame.  */
 static int
 mips_in_function_epilogue_p (struct gdbarch *gdbarch, CORE_ADDR pc)
 {
-  if (mips_pc_is_mips16 (pc))
+  if (mips_pc_is_mips16 (gdbarch, pc))
     return mips16_in_function_epilogue_p (gdbarch, pc);
+  else if (mips_pc_is_micromips (gdbarch, pc))
+    return micromips_in_function_epilogue_p (gdbarch, pc);
   else
     return mips32_in_function_epilogue_p (gdbarch, pc);
 }
 
 /* Root of all "set mips "/"show mips " commands.  This will eventually be
    used for all MIPS-specific commands.  */
 
 static void
 show_mips_command (char *args, int from_tty)
 {
@@ skipping 128 matching lines @@
 static void
 reinit_frame_cache_sfunc (char *args, int from_tty,
                           struct cmd_list_element *c)
 {
   reinit_frame_cache ();
 }
 
 static int
 gdb_print_insn_mips (bfd_vma memaddr, struct disassemble_info *info)
 {
+  struct gdbarch *gdbarch = info->application_data;
+
   /* FIXME: cagney/2003-06-26: Is this even necessary?  The
      disassembler needs to be able to locally determine the ISA, and
      not rely on GDB.  Otherwize the stand-alone 'objdump -d' will not
      work.  */
-  if (mips_pc_is_mips16 (memaddr))
+  if (mips_pc_is_mips16 (gdbarch, memaddr))
     info->mach = bfd_mach_mips16;
+  else if (mips_pc_is_micromips (gdbarch, memaddr))
+    info->mach = bfd_mach_mips_micromips;
 
   /* Round down the instruction address to the appropriate boundary.  */
-  memaddr &= (info->mach == bfd_mach_mips16 ? ~1 : ~3);
+  memaddr &= (info->mach == bfd_mach_mips16
+              || info->mach == bfd_mach_mips_micromips) ? ~1 : ~3;
 
   /* Set the disassembler options.  */
   if (!info->disassembler_options)
     /* This string is not recognized explicitly by the disassembler,
        but it tells the disassembler to not try to guess the ABI from
        the bfd elf headers, such that, if the user overrides the ABI
        of a program linked as NewABI, the disassembly will follow the
        register naming conventions specified by the user.  */
     info->disassembler_options = "gpr-names=32";
 
@@ skipping 30 matching lines @@
    program counter value to determine whether a 16- or 32-bit breakpoint
    should be used.  It returns a pointer to a string of bytes that encode a
    breakpoint instruction, stores the length of the string to *lenptr, and
    adjusts pc (if necessary) to point to the actual memory location where
    the breakpoint should be inserted.  */
 
 static const gdb_byte *
 mips_breakpoint_from_pc (struct gdbarch *gdbarch,
                          CORE_ADDR *pcptr, int *lenptr)
 {
+  CORE_ADDR pc = *pcptr;
+
   if (gdbarch_byte_order (gdbarch) == BFD_ENDIAN_BIG)
     {
-      if (mips_pc_is_mips16 (*pcptr))
+      if (mips_pc_is_mips16 (gdbarch, pc))
         {
           static gdb_byte mips16_big_breakpoint[] = { 0xe8, 0xa5 };
-          *pcptr = unmake_mips16_addr (*pcptr);
+          *pcptr = unmake_compact_addr (pc);
           *lenptr = sizeof (mips16_big_breakpoint);
           return mips16_big_breakpoint;
         }
+      else if (mips_pc_is_micromips (gdbarch, pc))
+        {
+          static gdb_byte micromips16_big_breakpoint[] = { 0x46, 0x85 };
+          static gdb_byte micromips32_big_breakpoint[] = { 0, 0x5, 0, 0x7 };
+          ULONGEST insn;
+          int status;
+          int size;
+
+          insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, &status);
+          size = status ? 2
+                        : mips_insn_size (ISA_MICROMIPS, insn) == 2 ? 2 : 4;
+          *pcptr = unmake_compact_addr (pc);
+          *lenptr = size;
+          return (size == 2) ? micromips16_big_breakpoint
+                             : micromips32_big_breakpoint;
+        }
       else
         {
           /* The IDT board uses an unusual breakpoint value, and
              sometimes gets confused when it sees the usual MIPS
              breakpoint instruction.  */
           static gdb_byte big_breakpoint[] = { 0, 0x5, 0, 0xd };
           static gdb_byte pmon_big_breakpoint[] = { 0, 0, 0, 0xd };
           static gdb_byte idt_big_breakpoint[] = { 0, 0, 0x0a, 0xd };
           /* Likewise, IRIX appears to expect a different breakpoint,
              although this is not apparent until you try to use pthreads.  */
           static gdb_byte irix_big_breakpoint[] = { 0, 0, 0, 0xd };
 
           *lenptr = sizeof (big_breakpoint);
 
           if (strcmp (target_shortname, "mips") == 0)
             return idt_big_breakpoint;
           else if (strcmp (target_shortname, "ddb") == 0
                    || strcmp (target_shortname, "pmon") == 0
                    || strcmp (target_shortname, "lsi") == 0)
             return pmon_big_breakpoint;
           else if (gdbarch_osabi (gdbarch) == GDB_OSABI_IRIX)
             return irix_big_breakpoint;
           else
             return big_breakpoint;
         }
     }
   else
     {
-      if (mips_pc_is_mips16 (*pcptr))
+      if (mips_pc_is_mips16 (gdbarch, pc))
         {
           static gdb_byte mips16_little_breakpoint[] = { 0xa5, 0xe8 };
-          *pcptr = unmake_mips16_addr (*pcptr);
+          *pcptr = unmake_compact_addr (pc);
           *lenptr = sizeof (mips16_little_breakpoint);
           return mips16_little_breakpoint;
         }
+      else if (mips_pc_is_micromips (gdbarch, pc))
+        {
+          static gdb_byte micromips16_little_breakpoint[] = { 0x85, 0x46 };
+          static gdb_byte micromips32_little_breakpoint[] = { 0x5, 0, 0x7, 0 };
+          ULONGEST insn;
+          int status;
+          int size;
+
+          insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, &status);
+          size = status ? 2
+                        : mips_insn_size (ISA_MICROMIPS, insn) == 2 ? 2 : 4;
+          *pcptr = unmake_compact_addr (pc);
+          *lenptr = size;
+          return (size == 2) ? micromips16_little_breakpoint
+                             : micromips32_little_breakpoint;
+        }
       else
         {
           static gdb_byte little_breakpoint[] = { 0xd, 0, 0x5, 0 };
           static gdb_byte pmon_little_breakpoint[] = { 0xd, 0, 0, 0 };
           static gdb_byte idt_little_breakpoint[] = { 0xd, 0x0a, 0, 0 };
 
           *lenptr = sizeof (little_breakpoint);
 
           if (strcmp (target_shortname, "mips") == 0)
             return idt_little_breakpoint;
           else if (strcmp (target_shortname, "ddb") == 0
                    || strcmp (target_shortname, "pmon") == 0
                    || strcmp (target_shortname, "lsi") == 0)
             return pmon_little_breakpoint;
           else
             return little_breakpoint;
         }
     }
 }
 
-/* If PC is in a mips16 call or return stub, return the address of the target
-   PC, which is either the callee or the caller.  There are several
+/* Determine the remote breakpoint kind suitable for the PC.  The following
+   kinds are used:
+
+   * 2 -- 16-bit MIPS16 mode breakpoint,
+
+   * 3 -- 16-bit microMIPS mode breakpoint,
+
+   * 4 -- 32-bit standard MIPS mode breakpoint,
+
+   * 5 -- 32-bit microMIPS mode breakpoint.  */
+
+static void
+mips_remote_breakpoint_from_pc (struct gdbarch *gdbarch, CORE_ADDR *pcptr,
+                                int *kindptr)
+{
+  CORE_ADDR pc = *pcptr;
+
+  if (mips_pc_is_mips16 (gdbarch, pc))
+    {
+      *pcptr = unmake_compact_addr (pc);
+      *kindptr = 2;
+    }
+  else if (mips_pc_is_micromips (gdbarch, pc))
+    {
+      ULONGEST insn;
+      int status;
+      int size;
+
+      insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, pc, &status);
+      size = status ? 2 : mips_insn_size (ISA_MICROMIPS, insn) == 2 ? 2 : 4;
+      *pcptr = unmake_compact_addr (pc);
+      *kindptr = size | 1;
+    }
+  else
+    *kindptr = 4;
+}
+
+/* Return non-zero if the ADDR instruction has a branch delay slot
+   (i.e. it is a jump or branch instruction).  This function is based
+   on mips32_next_pc.  */
+
+static int
+mips32_instruction_has_delay_slot (struct gdbarch *gdbarch, CORE_ADDR addr)
+{
+  unsigned long inst;
+  int status;
+  int op;
+  int rs;
+  int rt;
+
+  inst = mips_fetch_instruction (gdbarch, ISA_MIPS, addr, &status);
+  if (status)
+    return 0;
+
+  op = itype_op (inst);
+  if ((inst & 0xe0000000) != 0)
+    {
+      rs = itype_rs (inst);
+      rt = itype_rt (inst);
+      return (op >> 2 == 5      /* BEQL, BNEL, BLEZL, BGTZL: bits 0101xx  */
+              || op == 29       /* JALX: bits 011101  */
+              || (op == 17
+                  && (rs == 8
+                                /* BC1F, BC1FL, BC1T, BC1TL: 010001 01000  */
+                      || (rs == 9 && (rt & 0x2) == 0)
+                                /* BC1ANY2F, BC1ANY2T: bits 010001 01001  */
+                      || (rs == 10 && (rt & 0x2) == 0))));
+                                /* BC1ANY4F, BC1ANY4T: bits 010001 01010  */
+    }
+  else
+    switch (op & 0x07)          /* extract bits 28,27,26  */
+      {
+      case 0:                   /* SPECIAL  */
+        op = rtype_funct (inst);
+        return (op == 8         /* JR  */
+                || op == 9);    /* JALR  */
+        break;                  /* end SPECIAL  */
+      case 1:                   /* REGIMM  */
+        rs = itype_rs (inst);
+        rt = itype_rt (inst);   /* branch condition  */
+        return ((rt & 0xc) == 0
+                                /* BLTZ, BLTZL, BGEZ, BGEZL: bits 000xx  */
+                                /* BLTZAL, BLTZALL, BGEZAL, BGEZALL: 100xx  */
+                || ((rt & 0x1e) == 0x1c && rs == 0));
+                                /* BPOSGE32, BPOSGE64: bits 1110x  */
+        break;                  /* end REGIMM  */
+      default:                  /* J, JAL, BEQ, BNE, BLEZ, BGTZ  */
+        return 1;
+        break;
+      }
+}
+
+/* Return non-zero if the ADDR instruction, which must be a 32-bit
+   instruction if MUSTBE32 is set or can be any instruction otherwise,
+   has a branch delay slot (i.e. it is a non-compact jump instruction).  */
+
+static int
+micromips_instruction_has_delay_slot (struct gdbarch *gdbarch,
+                                      CORE_ADDR addr, int mustbe32)
+{
+  ULONGEST insn;
+  int status;
+
+  insn = mips_fetch_instruction (gdbarch, ISA_MICROMIPS, addr, &status);
+  if (status)
+    return 0;
+
+  if (!mustbe32)                /* 16-bit instructions.  */
+    return (micromips_op (insn) == 0x11
+                                /* POOL16C: bits 010001 */
+            && (b5s5_op (insn) == 0xc
+                                /* JR16: bits 010001 01100 */
+                || (b5s5_op (insn) & 0x1e) == 0xe))
+                                /* JALR16, JALRS16: bits 010001 0111x */
+           || (micromips_op (insn) & 0x37) == 0x23
+                                /* BEQZ16, BNEZ16: bits 10x011 */
+           || micromips_op (insn) == 0x33;
+                                /* B16: bits 110011 */
+
+                                /* 32-bit instructions.  */
+  if (micromips_op (insn) == 0x0)
+                                /* POOL32A: bits 000000 */
+    {
+      insn <<= 16;
+      insn |= mips_fetch_instruction (gdbarch, ISA_MICROMIPS, addr, &status);
+      if (status)
+        return 0;
+      return b0s6_op (insn) == 0x3c
+                                /* POOL32Axf: bits 000000 ... 111100 */
+             && (b6s10_ext (insn) & 0x2bf) == 0x3c;
+                                /* JALR, JALR.HB: 000000 000x111100 111100 */
+                                /* JALRS, JALRS.HB: 000000 010x111100 111100 */
+    }
+
+  return (micromips_op (insn) == 0x10
+                                /* POOL32I: bits 010000 */
+          && ((b5s5_op (insn) & 0x1c) == 0x0
+                                /* BLTZ, BLTZAL, BGEZ, BGEZAL: 010000 000xx */
+              || (b5s5_op (insn) & 0x1d) == 0x4
+                                /* BLEZ, BGTZ: bits 010000 001x0 */
+              || (b5s5_op (insn) & 0x1d) == 0x11
+                                /* BLTZALS, BGEZALS: bits 010000 100x1 */
+              || ((b5s5_op (insn) & 0x1e) == 0x14
+                  && (insn & 0x3) == 0x0)
+                                /* BC2F, BC2T: bits 010000 1010x xxx00 */
+              || (b5s5_op (insn) & 0x1e) == 0x1a
+                                /* BPOSGE64, BPOSGE32: bits 010000 1101x */
+              || ((b5s5_op (insn) & 0x1e) == 0x1c
+                  && (insn & 0x3) == 0x0)
+                                /* BC1F, BC1T: bits 010000 1110x xxx00 */
+              || ((b5s5_op (insn) & 0x1c) == 0x1c
+                  && (insn & 0x3) == 0x1)))
+                                /* BC1ANY*: bits 010000 111xx xxx01 */
+         || (micromips_op (insn) & 0x1f) == 0x1d
+                                /* JALS, JAL: bits x11101 */
+         || (micromips_op (insn) & 0x37) == 0x25
+                                /* BEQ, BNE: bits 10x101 */
+         || micromips_op (insn) == 0x35
+                                /* J: bits 110101 */
+         || micromips_op (insn) == 0x3c;
+                                /* JALX: bits 111100 */
+}
+
+static int
+mips16_instruction_has_delay_slot (struct gdbarch *gdbarch, CORE_ADDR addr,
+                                   int mustbe32)
+{
+  unsigned short inst;
+  int status;
+
+  inst = mips_fetch_instruction (gdbarch, ISA_MIPS16, addr, &status);
+  if (status)
+    return 0;
+
+  if (!mustbe32)
+    return (inst & 0xf89f) == 0xe800;   /* JR/JALR (16-bit instruction)  */
+  return (inst & 0xf800) == 0x1800;     /* JAL/JALX (32-bit instruction)  */
+}
+
+/* Calculate the starting address of the MIPS memory segment BPADDR is in.
+   This assumes KSSEG exists.  */
+
+static CORE_ADDR
+mips_segment_boundary (CORE_ADDR bpaddr)
+{
+  CORE_ADDR mask = CORE_ADDR_MAX;
+  int segsize;
+
+  if (sizeof (CORE_ADDR) == 8)
+    /* Get the topmost two bits of bpaddr in a 32-bit safe manner (avoid
+       a compiler warning produced where CORE_ADDR is a 32-bit type even
+       though in that case this is dead code).  */
+    switch (bpaddr >> ((sizeof (CORE_ADDR) << 3) - 2) & 3)
+      {
+      case 3:
+        if (bpaddr == (bfd_signed_vma) (int32_t) bpaddr)
+          segsize = 29;                 /* 32-bit compatibility segment  */
+        else
+          segsize = 62;                 /* xkseg  */
+        break;
+      case 2:                           /* xkphys  */
+        segsize = 59;
+        break;
+      default:                          /* xksseg (1), xkuseg/kuseg (0)  */
+        segsize = 62;
+        break;
+      }
+  else if (bpaddr & 0x80000000)         /* kernel segment  */
+    segsize = 29;
+  else
+    segsize = 31;                       /* user segment  */
+  mask <<= segsize;
+  return bpaddr & mask;
+}
+
+/* Move the breakpoint at BPADDR out of any branch delay slot by shifting
+   it backwards if necessary.  Return the address of the new location.  */
+
+static CORE_ADDR
+mips_adjust_breakpoint_address (struct gdbarch *gdbarch, CORE_ADDR bpaddr)
+{
+  CORE_ADDR prev_addr;
+  CORE_ADDR boundary;
+  CORE_ADDR func_addr;
+
+  /* If a breakpoint is set on the instruction in a branch delay slot,
+     GDB gets confused.  When the breakpoint is hit, the PC isn't on
+     the instruction in the branch delay slot, the PC will point to
+     the branch instruction.  Since the PC doesn't match any known
+     breakpoints, GDB reports a trap exception.
+
+     There are two possible fixes for this problem.
+
+     1) When the breakpoint gets hit, see if the BD bit is set in the
+     Cause register (which indicates the last exception occurred in a
+     branch delay slot).  If the BD bit is set, fix the PC to point to
+     the instruction in the branch delay slot.
+
+     2) When the user sets the breakpoint, don't allow him to set the
+     breakpoint on the instruction in the branch delay slot.  Instead
+     move the breakpoint to the branch instruction (which will have
+     the same result).
+
+     The problem with the first solution is that if the user then
+     single-steps the processor, the branch instruction will get
+     skipped (since GDB thinks the PC is on the instruction in the
+     branch delay slot).
+
+     So, we'll use the second solution.  To do this we need to know if
+     the instruction we're trying to set the breakpoint on is in the
+     branch delay slot.  */
+
+  boundary = mips_segment_boundary (bpaddr);
+
+  /* Make sure we don't scan back before the beginning of the current
+     function, since we may fetch constant data or insns that look like
+     a jump.  Of course we might do that anyway if the compiler has
+     moved constants inline. :-(  */
+  if (find_pc_partial_function (bpaddr, NULL, &func_addr, NULL)
+      && func_addr > boundary && func_addr <= bpaddr)
+    boundary = func_addr;
+
+  if (mips_pc_is_mips (bpaddr))
+    {
+      if (bpaddr == boundary)
+        return bpaddr;
+
+      /* If the previous instruction has a branch delay slot, we have
+         to move the breakpoint to the branch instruction. */
+      prev_addr = bpaddr - 4;
+      if (mips32_instruction_has_delay_slot (gdbarch, prev_addr))
+        bpaddr = prev_addr;
+    }
+  else
+    {
+      int (*instruction_has_delay_slot) (struct gdbarch *, CORE_ADDR, int);
+      CORE_ADDR addr, jmpaddr;
+      int i;
+
+      boundary = unmake_compact_addr (boundary);
+
+      /* The only MIPS16 instructions with delay slots are JAL, JALX,
+         JALR and JR.  An absolute JAL/JALX is always 4 bytes long,
+         so try for that first, then try the 2 byte JALR/JR.
+         The microMIPS ASE has a whole range of jumps and branches
+         with delay slots, some of which take 4 bytes and some take
+         2 bytes, so the idea is the same.
+         FIXME: We have to assume that bpaddr is not the second half
+         of an extended instruction.  */
+      instruction_has_delay_slot = (mips_pc_is_micromips (gdbarch, bpaddr)
+                                     ? micromips_instruction_has_delay_slot
+                                     : mips16_instruction_has_delay_slot);
+
+      jmpaddr = 0;
+      addr = bpaddr;
+      for (i = 1; i < 4; i++)
+        {
+          if (unmake_compact_addr (addr) == boundary)
+            break;
+          addr -= MIPS_INSN16_SIZE;
+          if (i == 1 && instruction_has_delay_slot (gdbarch, addr, 0))
+            /* Looks like a JR/JALR at [target-1], but it could be
+               the second word of a previous JAL/JALX, so record it
+               and check back one more.  */
+            jmpaddr = addr;
+          else if (i > 1 && instruction_has_delay_slot (gdbarch, addr, 1))
+            {
+              if (i == 2)
+                /* Looks like a JAL/JALX at [target-2], but it could also
+                   be the second word of a previous JAL/JALX, record it,
+                   and check back one more.  */
+                jmpaddr = addr;
+              else
+                /* Looks like a JAL/JALX at [target-3], so any previously
+                   recorded JAL/JALX or JR/JALR must be wrong, because:
+
+                   >-3: JAL
+                    -2: JAL-ext (can't be JAL/JALX)
+                    -1: bdslot (can't be JR/JALR)
+                     0: target insn
+
+                   Of course it could be another JAL-ext which looks
+                   like a JAL, but in that case we'd have broken out
+                   of this loop at [target-2]:
+
+                    -4: JAL
+                   >-3: JAL-ext
+                    -2: bdslot (can't be jmp)
+                    -1: JR/JALR
+                     0: target insn  */
+                jmpaddr = 0;
+            }
+          else
+            {
+              /* Not a jump instruction: if we're at [target-1] this
+                 could be the second word of a JAL/JALX, so continue;
+                 otherwise we're done.  */
+              if (i > 1)
+                break;
+            }
+        }
+
+      if (jmpaddr)
+        bpaddr = jmpaddr;
+    }
+
+  return bpaddr;
+}
+
+/* Return non-zero if SUFFIX is one of the numeric suffixes used for MIPS16
+   call stubs, one of 1, 2, 5, 6, 9, 10, or, if ZERO is non-zero, also 0.  */
+
+static int
+mips_is_stub_suffix (const char *suffix, int zero)
+{
+  switch (suffix[0])
+   {
+   case '0':
+     return zero && suffix[1] == '\0';
+   case '1':
+     return suffix[1] == '\0' || (suffix[1] == '0' && suffix[2] == '\0');
+   case '2':
+   case '5':
+   case '6':
+   case '9':
+     return suffix[1] == '\0';
+   default:
+     return 0;
+   }
+}
+
+/* Return non-zero if MODE is one of the mode infixes used for MIPS16
+   call stubs, one of sf, df, sc, or dc.  */
+
+static int
+mips_is_stub_mode (const char *mode)
+{
+  return ((mode[0] == 's' || mode[0] == 'd')
+          && (mode[1] == 'f' || mode[1] == 'c'));
+}
+
+/* Code at PC is a compiler-generated stub.  Such a stub for a function
+   bar might have a name like __fn_stub_bar, and might look like this:
+
+      mfc1    $4, $f13
+      mfc1    $5, $f12
+      mfc1    $6, $f15
+      mfc1    $7, $f14
+
+   followed by (or interspersed with):
+
+      j       bar
+
+   or:
+
+      lui     $25, %hi(bar)
+      addiu   $25, $25, %lo(bar)
+      jr      $25
+
+   ($1 may be used in old code; for robustness we accept any register)
+   or, in PIC code:
+
+      lui     $28, %hi(_gp_disp)
+      addiu   $28, $28, %lo(_gp_disp)
+      addu    $28, $28, $25
+      lw      $25, %got(bar)
+      addiu   $25, $25, %lo(bar)
+      jr      $25
+
+   In the case of a __call_stub_bar stub, the sequence to set up
+   arguments might look like this:
+
+      mtc1    $4, $f13
+      mtc1    $5, $f12
+      mtc1    $6, $f15
+      mtc1    $7, $f14
+
+   followed by (or interspersed with) one of the jump sequences above.
+
+   In the case of a __call_stub_fp_bar stub, JAL or JALR is used instead
+   of J or JR, respectively, followed by:
+
+      mfc1    $2, $f0
+      mfc1    $3, $f1
+      jr      $18
+
+   We are at the beginning of the stub here, and scan down and extract
+   the target address from the jump immediate instruction or, if a jump
+   register instruction is used, from the register referred.  Return
+   the value of PC calculated or 0 if inconclusive.
+
+   The limit on the search is arbitrarily set to 20 instructions.  FIXME.  */
+
+static CORE_ADDR
+mips_get_mips16_fn_stub_pc (struct frame_info *frame, CORE_ADDR pc)
+{
+  struct gdbarch *gdbarch = get_frame_arch (frame);
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
+  int addrreg = MIPS_ZERO_REGNUM;
+  CORE_ADDR start_pc = pc;
+  CORE_ADDR target_pc = 0;
+  CORE_ADDR addr = 0;
+  CORE_ADDR gp = 0;
+  int status = 0;
+  int i;
+
+  for (i = 0;
+       status == 0 && target_pc == 0 && i < 20;
+       i++, pc += MIPS_INSN32_SIZE)
+    {
+      ULONGEST inst = mips_fetch_instruction (gdbarch, ISA_MIPS, pc, NULL);
+      CORE_ADDR imm;
+      int rt;
+      int rs;
+      int rd;
+
+      switch (itype_op (inst))
+        {
+        case 0:         /* SPECIAL */
+          switch (rtype_funct (inst))
+            {
+            case 8:             /* JR */
+            case 9:             /* JALR */
+              rs = rtype_rs (inst);
+              if (rs == MIPS_GP_REGNUM)
+                target_pc = gp;                         /* Hmm...  */
+              else if (rs == addrreg)
+                target_pc = addr;
+              break;
+
+            case 0x21:          /* ADDU */
+              rt = rtype_rt (inst);
+              rs = rtype_rs (inst);
+              rd = rtype_rd (inst);
+              if (rd == MIPS_GP_REGNUM
+                  && ((rs == MIPS_GP_REGNUM && rt == MIPS_T9_REGNUM)
+                      || (rs == MIPS_T9_REGNUM && rt == MIPS_GP_REGNUM)))
+                gp += start_pc;
+              break;
+            }
+          break;
+
+        case 2:         /* J */
+        case 3:         /* JAL */
+          target_pc = jtype_target (inst) << 2;
+          target_pc += ((pc + 4) & ~(CORE_ADDR) 0x0fffffff);
+          break;
+
+        case 9:         /* ADDIU */
+          rt = itype_rt (inst);
+          rs = itype_rs (inst);
+          if (rt == rs)
+            {
+              imm = (itype_immediate (inst) ^ 0x8000) - 0x8000;
+              if (rt == MIPS_GP_REGNUM)
+                gp += imm;
+              else if (rt == addrreg)
+                addr += imm;
+            }
+          break;
+
+        case 0xf:       /* LUI */
+          rt = itype_rt (inst);
+          imm = ((itype_immediate (inst) ^ 0x8000) - 0x8000) << 16;
+          if (rt == MIPS_GP_REGNUM)
+            gp = imm;
+          else if (rt != MIPS_ZERO_REGNUM)
+            {
+              addrreg = rt;
+              addr = imm;
+            }
+          break;
+
+        case 0x23:      /* LW */
+          rt = itype_rt (inst);
+          rs = itype_rs (inst);
+          imm = (itype_immediate (inst) ^ 0x8000) - 0x8000;
+          if (gp != 0 && rs == MIPS_GP_REGNUM)
+            {
+              gdb_byte buf[4];
+
+              memset (buf, 0, sizeof (buf));
+              status = target_read_memory (gp + imm, buf, sizeof (buf));
+              addrreg = rt;
+              addr = extract_signed_integer (buf, sizeof (buf), byte_order);
+            }
+          break;
+        }
+    }
+
+  return target_pc;
+}
+
+/* If PC is in a MIPS16 call or return stub, return the address of the
+   target PC, which is either the callee or the caller.  There are several
    cases which must be handled:
 
-   * If the PC is in __mips16_ret_{d,s}f, this is a return stub and the
-   target PC is in $31 ($ra).
+   * If the PC is in __mips16_ret_{d,s}{f,c}, this is a return stub
+     and the target PC is in $31 ($ra).
    * If the PC is in __mips16_call_stub_{1..10}, this is a call stub
-   and the target PC is in $2.
-   * If the PC at the start of __mips16_call_stub_{s,d}f_{0..10}, i.e.
-   before the jal instruction, this is effectively a call stub
-   and the target PC is in $2.  Otherwise this is effectively
-   a return stub and the target PC is in $18.
-
-   See the source code for the stubs in gcc/config/mips/mips16.S for
+     and the target PC is in $2.
+   * If the PC at the start of __mips16_call_stub_{s,d}{f,c}_{0..10},
+     i.e. before the JALR instruction, this is effectively a call stub
+     and the target PC is in $2.  Otherwise this is effectively
+     a return stub and the target PC is in $18.
+   * If the PC is at the start of __call_stub_fp_*, i.e. before the
+     JAL or JALR instruction, this is effectively a call stub and the
+     target PC is buried in the instruction stream.  Otherwise this
+     is effectively a return stub and the target PC is in $18.
+   * If the PC is in __call_stub_* or in __fn_stub_*, this is a call
+     stub and the target PC is buried in the instruction stream.
+
+   See the source code for the stubs in gcc/config/mips/mips16.S, or the
+   stub builder in gcc/config/mips/mips.c (mips16_build_call_stub) for the
    gory details.  */
 
 static CORE_ADDR
 mips_skip_mips16_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
-  char *name;
   CORE_ADDR start_addr;
+  const char *name;
+  size_t prefixlen;
 
   /* Find the starting address and name of the function containing the PC.  */
   if (find_pc_partial_function (pc, &name, &start_addr, NULL) == 0)
     return 0;
 
-  /* If the PC is in __mips16_ret_{d,s}f, this is a return stub and the
-     target PC is in $31 ($ra).  */
-  if (strcmp (name, "__mips16_ret_sf") == 0
-      || strcmp (name, "__mips16_ret_df") == 0)
-    return get_frame_register_signed (frame, MIPS_RA_REGNUM);
-
-  if (strncmp (name, "__mips16_call_stub_", 19) == 0)
+  /* If the PC is in __mips16_ret_{d,s}{f,c}, this is a return stub
+     and the target PC is in $31 ($ra).  */
+  prefixlen = strlen (mips_str_mips16_ret_stub);
+  if (strncmp (name, mips_str_mips16_ret_stub, prefixlen) == 0
+      && mips_is_stub_mode (name + prefixlen)
+      && name[prefixlen + 2] == '\0')
+    return get_frame_register_signed
+             (frame, gdbarch_num_regs (gdbarch) + MIPS_RA_REGNUM);
+
+  /* If the PC is in __mips16_call_stub_*, this is one of the call
+     call/return stubs.  */
+  prefixlen = strlen (mips_str_mips16_call_stub);
+  if (strncmp (name, mips_str_mips16_call_stub, prefixlen) == 0)
     {
       /* If the PC is in __mips16_call_stub_{1..10}, this is a call stub
          and the target PC is in $2.  */
-      if (name[19] >= '0' && name[19] <= '9')
-        return get_frame_register_signed (frame, 2);
-
-      /* If the PC at the start of __mips16_call_stub_{s,d}f_{0..10}, i.e.
-         before the jal instruction, this is effectively a call stub
+      if (mips_is_stub_suffix (name + prefixlen, 0))
+        return get_frame_register_signed
+                 (frame, gdbarch_num_regs (gdbarch) + MIPS_V0_REGNUM);
+
+      /* If the PC at the start of __mips16_call_stub_{s,d}{f,c}_{0..10},
+         i.e. before the JALR instruction, this is effectively a call stub
          and the target PC is in $2.  Otherwise this is effectively
          a return stub and the target PC is in $18.  */
-      else if (name[19] == 's' || name[19] == 'd')
+      else if (mips_is_stub_mode (name + prefixlen)
+               && name[prefixlen + 2] == '_'
+               && mips_is_stub_suffix (name + prefixlen + 3, 0))
         {
           if (pc == start_addr)
-            {
-              /* Check if the target of the stub is a compiler-generated
-                 stub.  Such a stub for a function bar might have a name
-                 like __fn_stub_bar, and might look like this:
-                 mfc1    $4,$f13
-                 mfc1    $5,$f12
-                 mfc1    $6,$f15
-                 mfc1    $7,$f14
-                 la      $1,bar   (becomes a lui/addiu pair)
-                 jr      $1
-                 So scan down to the lui/addi and extract the target
-                 address from those two instructions.  */
-
-              CORE_ADDR target_pc = get_frame_register_signed (frame, 2);
-              int i;
-
-              /* See if the name of the target function is  __fn_stub_*.  */
-              if (find_pc_partial_function (target_pc, &name, NULL, NULL) ==
-                  0)
-                return target_pc;
-              if (strncmp (name, "__fn_stub_", 10) != 0
-                  && strcmp (name, "etext") != 0
-                  && strcmp (name, "_etext") != 0)
-                return target_pc;
-
-              /* Scan through this _fn_stub_ code for the lui/addiu pair.
-                 The limit on the search is arbitrarily set to 20
-                 instructions.  FIXME.  */
-              for (i = 0, pc = 0; i < 20; i++, target_pc += MIPS_INSN32_SIZE)
-                {
-                  ULONGEST inst = mips_fetch_instruction (gdbarch, target_pc);
-                  CORE_ADDR addr = inst;
-
-                  if ((inst & 0xffff0000) == 0x3c010000)        /* lui $at */
-                    pc = (((addr & 0xffff) ^ 0x8000) - 0x8000) << 16;
-                                                                /* high word */
-                  else if ((inst & 0xffff0000) == 0x24210000)   /* addiu $at */
-                    return pc + ((addr & 0xffff) ^ 0x8000) - 0x8000;
-                                                                /* low word */
-                }
-
-              /* Couldn't find the lui/addui pair, so return stub address.  */
-              return target_pc;
-            }
+            /* This is the 'call' part of a call stub.  The return
+               address is in $2.  */
+            return get_frame_register_signed
+                     (frame, gdbarch_num_regs (gdbarch) + MIPS_V0_REGNUM);
           else
             /* This is the 'return' part of a call stub.  The return
-               address is in $r18.  */
-            return get_frame_register_signed (frame, 18);
+               address is in $18.  */
+            return get_frame_register_signed
+                     (frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM);
         }
-    }
-  return 0;                     /* not a stub */
+      else
+        return 0;               /* Not a stub.  */
+    }
+
+  /* If the PC is in __call_stub_* or __fn_stub*, this is one of the
+     compiler-generated call or call/return stubs.  */
+  if (strncmp (name, mips_str_fn_stub, strlen (mips_str_fn_stub)) == 0
+      || strncmp (name, mips_str_call_stub, strlen (mips_str_call_stub)) == 0)
+    {
+      if (pc == start_addr)
+        /* This is the 'call' part of a call stub.  Call this helper
+           to scan through this code for interesting instructions
+           and determine the final PC.  */
+        return mips_get_mips16_fn_stub_pc (frame, pc);
+      else
+        /* This is the 'return' part of a call stub.  The return address
+           is in $18.  */
+        return get_frame_register_signed
+                 (frame, gdbarch_num_regs (gdbarch) + MIPS_S2_REGNUM);
+    }
+
+  return 0;                     /* Not a stub.  */
+}
+
+/* Return non-zero if the PC is inside a return thunk (aka stub or trampoline).
+   This implements the IN_SOLIB_RETURN_TRAMPOLINE macro.  */
+
+static int
+mips_in_return_stub (struct gdbarch *gdbarch, CORE_ADDR pc, const char *name)
+{
+  CORE_ADDR start_addr;
+  size_t prefixlen;
+
+  /* Find the starting address of the function containing the PC.  */
+  if (find_pc_partial_function (pc, NULL, &start_addr, NULL) == 0)
+    return 0;
+
+  /* If the PC is in __mips16_call_stub_{s,d}{f,c}_{0..10} but not at
+     the start, i.e. after the JALR instruction, this is effectively
+     a return stub.  */
+  prefixlen = strlen (mips_str_mips16_call_stub);
+  if (pc != start_addr
+      && strncmp (name, mips_str_mips16_call_stub, prefixlen) == 0
+      && mips_is_stub_mode (name + prefixlen)
+      && name[prefixlen + 2] == '_'
+      && mips_is_stub_suffix (name + prefixlen + 3, 1))
+    return 1;
+
+  /* If the PC is in __call_stub_fp_* but not at the start, i.e. after
+     the JAL or JALR instruction, this is effectively a return stub.  */
+  prefixlen = strlen (mips_str_call_fp_stub);
+  if (pc != start_addr
+      && strncmp (name, mips_str_call_fp_stub, prefixlen) == 0)
+    return 1;
+
+  /* Consume the .pic. prefix of any PIC stub, this function must return
+     true when the PC is in a PIC stub of a __mips16_ret_{d,s}{f,c} stub
+     or the call stub path will trigger in handle_inferior_event causing
+     it to go astray.  */
+  prefixlen = strlen (mips_str_pic);
+  if (strncmp (name, mips_str_pic, prefixlen) == 0)
+    name += prefixlen;
+
+  /* If the PC is in __mips16_ret_{d,s}{f,c}, this is a return stub.  */
+  prefixlen = strlen (mips_str_mips16_ret_stub);
+  if (strncmp (name, mips_str_mips16_ret_stub, prefixlen) == 0
+      && mips_is_stub_mode (name + prefixlen)
+      && name[prefixlen + 2] == '\0')
+    return 1;
+
+  return 0;                     /* Not a stub.  */
 }
 
 /* If the current PC is the start of a non-PIC-to-PIC stub, return the
    PC of the stub target.  The stub just loads $t9 and jumps to it,
    so that $t9 has the correct value at function entry.  */
 
 static CORE_ADDR
 mips_skip_pic_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 {
   struct gdbarch *gdbarch = get_frame_arch (frame);
@@ skipping 31 matching lines @@
          j      target
           addiu t9, t9, %lo(target)
          nop
 
          This works even for N64, since stubs are only generated with
          -msym32.  */
       if ((stub_words[0] & 0xffff0000U) == 0x3c190000
           && (stub_words[1] & 0xfc000000U) == 0x08000000
           && (stub_words[2] & 0xffff0000U) == 0x27390000
           && stub_words[3] == 0x00000000)
-        return (((stub_words[0] & 0x0000ffff) << 16)
-                + (stub_words[2] & 0x0000ffff));
+        return ((((stub_words[0] & 0x0000ffff) << 16)
+                 + (stub_words[2] & 0x0000ffff)) ^ 0x8000) - 0x8000;
     }
 
   /* Not a recognized stub.  */
   return 0;
 }
 
 static CORE_ADDR
 mips_skip_trampoline_code (struct frame_info *frame, CORE_ADDR pc)
 {
+  CORE_ADDR requested_pc = pc;
   CORE_ADDR target_pc;
+  CORE_ADDR new_pc;
 
-  target_pc = mips_skip_mips16_trampoline_code (frame, pc);
-  if (target_pc)
-    return target_pc;
+  do
+    {
+      target_pc = pc;
 
-  target_pc = find_solib_trampoline_target (frame, pc);
-  if (target_pc)
-    return target_pc;
+      new_pc = mips_skip_mips16_trampoline_code (frame, pc);
+      if (new_pc)
+        {
+          pc = new_pc;
+          if (is_compact_addr (pc))
+            pc = unmake_compact_addr (pc);
+        }
 
-  target_pc = mips_skip_pic_trampoline_code (frame, pc);
-  if (target_pc)
-    return target_pc;
+      new_pc = find_solib_trampoline_target (frame, pc);
+      if (new_pc)
+        {
+          pc = new_pc;
+          if (is_compact_addr (pc))
+            pc = unmake_compact_addr (pc);
+        }
 
-  return 0;
+      new_pc = mips_skip_pic_trampoline_code (frame, pc);
+      if (new_pc)
+        {
+          pc = new_pc;
+          if (is_compact_addr (pc))
+            pc = unmake_compact_addr (pc);
+        }
+    }
+  while (pc != target_pc);
+
+  return pc != requested_pc ? pc : 0;
 }
 
 /* Convert a dbx stab register number (from `r' declaration) to a GDB
    [1 * gdbarch_num_regs .. 2 * gdbarch_num_regs) REGNUM.  */
 
 static int
 mips_stab_reg_to_regnum (struct gdbarch *gdbarch, int num)
 {
   int regnum;
   if (num >= 0 && num < 32)
     regnum = num;
   else if (num >= 38 && num < 70)
     regnum = num + mips_regnum (gdbarch)->fp0 - 38;
   else if (num == 70)
     regnum = mips_regnum (gdbarch)->hi;
   else if (num == 71)
     regnum = mips_regnum (gdbarch)->lo;
+  else if (mips_regnum (gdbarch)->dspacc != -1 && num >= 72 && num < 78)
+    regnum = num + mips_regnum (gdbarch)->dspacc - 72;
   else
     /* This will hopefully (eventually) provoke a warning.  Should
        we be calling complaint() here?  */
     return gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
   return gdbarch_num_regs (gdbarch) + regnum;
 }
 
 
 /* Convert a dwarf, dwarf2, or ecoff register number to a GDB [1 *
    gdbarch_num_regs .. 2 * gdbarch_num_regs) REGNUM.  */
 
 static int
 mips_dwarf_dwarf2_ecoff_reg_to_regnum (struct gdbarch *gdbarch, int num)
 {
   int regnum;
   if (num >= 0 && num < 32)
     regnum = num;
   else if (num >= 32 && num < 64)
     regnum = num + mips_regnum (gdbarch)->fp0 - 32;
   else if (num == 64)
     regnum = mips_regnum (gdbarch)->hi;
   else if (num == 65)
     regnum = mips_regnum (gdbarch)->lo;
+  else if (mips_regnum (gdbarch)->dspacc != -1 && num >= 66 && num < 72)
+    regnum = num + mips_regnum (gdbarch)->dspacc - 66;
   else
     /* This will hopefully (eventually) provoke a warning.  Should we
        be calling complaint() here?  */
     return gdbarch_num_regs (gdbarch) + gdbarch_num_pseudo_regs (gdbarch);
   return gdbarch_num_regs (gdbarch) + regnum;
 }
 
 static int
 mips_register_sim_regno (struct gdbarch *gdbarch, int regnum)
 {
@@ skipping 84 matching lines @@
 {
   int i;
 
   for (i = 0; mips_abi_strings[i] != NULL; i++)
     if (mips_abi_strings[i] == mips_abi_string)
       return (enum mips_abi) i;
 
   internal_error (__FILE__, __LINE__, _("unknown ABI string"));
 }
 
+/* Return the default compressed instruction set, either of MIPS16
+   or microMIPS, selected when none could have been determined from
+   the ELF header of the binary being executed (or no binary has been
+   selected.  */
+
+static enum mips_isa
+global_mips_compression (void)
+{
+  int i;
+
+  for (i = 0; mips_compression_strings[i] != NULL; i++)
+    if (mips_compression_strings[i] == mips_compression_string)
+      return (enum mips_isa) i;
+
+  internal_error (__FILE__, __LINE__, _("unknown compressed ISA string"));
+}
+
 static void
 mips_register_g_packet_guesses (struct gdbarch *gdbarch)
 {
   /* If the size matches the set of 32-bit or 64-bit integer registers,
      assume that's what we've got.  */
   register_remote_g_packet_guess (gdbarch, 38 * 4, mips_tdesc_gp32);
   register_remote_g_packet_guess (gdbarch, 38 * 8, mips_tdesc_gp64);
 
   /* If the size matches the full set of registers GDB traditionally
      knows about, including floating point, for either 32-bit or
@@ skipping 15 matching lines @@
 mips_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 {
   struct gdbarch *gdbarch;
   struct gdbarch_tdep *tdep;
   int elf_flags;
   enum mips_abi mips_abi, found_abi, wanted_abi;
   int i, num_regs;
   enum mips_fpu_type fpu_type;
   struct tdesc_arch_data *tdesc_data = NULL;
   int elf_fpu_type = 0;
+  const char **reg_names;
+  struct mips_regnum mips_regnum, *regnum;
+  enum mips_isa mips_isa;
+  int dspacc;
+  int dspctl;
+
+  /* Fill in the OS dependent register numbers and names.  */
+  if (info.osabi == GDB_OSABI_IRIX)
+    {
+      mips_regnum.fp0 = 32;
+      mips_regnum.pc = 64;
+      mips_regnum.cause = 65;
+      mips_regnum.badvaddr = 66;
+      mips_regnum.hi = 67;
+      mips_regnum.lo = 68;
+      mips_regnum.fp_control_status = 69;
+      mips_regnum.fp_implementation_revision = 70;
+      mips_regnum.dspacc = dspacc = -1;
+      mips_regnum.dspctl = dspctl = -1;
+      num_regs = 71;
+      reg_names = mips_irix_reg_names;
+    }
+  else if (info.osabi == GDB_OSABI_LINUX)
+    {
+      mips_regnum.fp0 = 38;
+      mips_regnum.pc = 37;
+      mips_regnum.cause = 36;
+      mips_regnum.badvaddr = 35;
+      mips_regnum.hi = 34;
+      mips_regnum.lo = 33;
+      mips_regnum.fp_control_status = 70;
+      mips_regnum.fp_implementation_revision = 71;
+      mips_regnum.dspacc = -1;
+      mips_regnum.dspctl = -1;
+      dspacc = 72;
+      dspctl = 78;
+      num_regs = 79;
+      reg_names = mips_linux_reg_names;
+    }
+  else
+    {
+      mips_regnum.lo = MIPS_EMBED_LO_REGNUM;
+      mips_regnum.hi = MIPS_EMBED_HI_REGNUM;
+      mips_regnum.badvaddr = MIPS_EMBED_BADVADDR_REGNUM;
+      mips_regnum.cause = MIPS_EMBED_CAUSE_REGNUM;
+      mips_regnum.pc = MIPS_EMBED_PC_REGNUM;
+      mips_regnum.fp0 = MIPS_EMBED_FP0_REGNUM;
+      mips_regnum.fp_control_status = 70;
+      mips_regnum.fp_implementation_revision = 71;
+      mips_regnum.dspacc = dspacc = -1;
+      mips_regnum.dspctl = dspctl = -1;
+      num_regs = MIPS_LAST_EMBED_REGNUM + 1;
+      if (info.bfd_arch_info != NULL
+          && info.bfd_arch_info->mach == bfd_mach_mips3900)
+        reg_names = mips_tx39_reg_names;
+      else
+        reg_names = mips_generic_reg_names;
+    }
 
   /* Check any target description for validity.  */
   if (tdesc_has_registers (info.target_desc))
     {
       static const char *const mips_gprs[] = {
         "r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7",
         "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",
         "r16", "r17", "r18", "r19", "r20", "r21", "r22", "r23",
         "r24", "r25", "r26", "r27", "r28", "r29", "r30", "r31"
       };
@@ skipping 14 matching lines @@
 
       tdesc_data = tdesc_data_alloc ();
 
       valid_p = 1;
       for (i = MIPS_ZERO_REGNUM; i <= MIPS_RA_REGNUM; i++)
         valid_p &= tdesc_numbered_register (feature, tdesc_data, i,
                                             mips_gprs[i]);
 
 
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_LO_REGNUM, "lo");
+                                          mips_regnum.lo, "lo");
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_HI_REGNUM, "hi");
+                                          mips_regnum.hi, "hi");
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_PC_REGNUM, "pc");
+                                          mips_regnum.pc, "pc");
 
       if (!valid_p)
         {
           tdesc_data_cleanup (tdesc_data);
           return NULL;
         }
 
       feature = tdesc_find_feature (info.target_desc,
                                     "org.gnu.gdb.mips.cp0");
       if (feature == NULL)
         {
           tdesc_data_cleanup (tdesc_data);
           return NULL;
         }
 
       valid_p = 1;
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_BADVADDR_REGNUM,
-                                          "badvaddr");
+                                          mips_regnum.badvaddr, "badvaddr");
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
                                           MIPS_PS_REGNUM, "status");
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_CAUSE_REGNUM, "cause");
+                                          mips_regnum.cause, "cause");
 
       if (!valid_p)
         {
           tdesc_data_cleanup (tdesc_data);
           return NULL;
         }
 
       /* FIXME drow/2007-05-17: The FPU should be optional.  The MIPS
          backend is not prepared for that, though.  */
       feature = tdesc_find_feature (info.target_desc,
                                     "org.gnu.gdb.mips.fpu");
       if (feature == NULL)
         {
           tdesc_data_cleanup (tdesc_data);
           return NULL;
         }
 
       valid_p = 1;
       for (i = 0; i < 32; i++)
         valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                            i + MIPS_EMBED_FP0_REGNUM,
-                                            mips_fprs[i]);
+                                            i + mips_regnum.fp0, mips_fprs[i]);
 
       valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_FP0_REGNUM + 32, "fcsr");
-      valid_p &= tdesc_numbered_register (feature, tdesc_data,
-                                          MIPS_EMBED_FP0_REGNUM + 33, "fir");
+                                          mips_regnum.fp_control_status,
+                                          "fcsr");
+      valid_p
+        &= tdesc_numbered_register (feature, tdesc_data,
+                                    mips_regnum.fp_implementation_revision,
+                                    "fir");
 
       if (!valid_p)
         {
           tdesc_data_cleanup (tdesc_data);
           return NULL;
         }
 
+      if (dspacc >= 0)
+        {
+          feature = tdesc_find_feature (info.target_desc,
+                                        "org.gnu.gdb.mips.dsp");
+          /* The DSP registers are optional; it's OK if they are absent.  */
+          if (feature != NULL)
+            {
+              i = 0;
+              valid_p = 1;
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspacc + i++, "hi1");
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspacc + i++, "lo1");
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspacc + i++, "hi2");
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspacc + i++, "lo2");
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspacc + i++, "hi3");
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspacc + i++, "lo3");
+
+              valid_p &= tdesc_numbered_register (feature, tdesc_data,
+                                                  dspctl, "dspctl");
+
+              if (!valid_p)
+                {
+                  tdesc_data_cleanup (tdesc_data);
+                  return NULL;
+                }
+
+              mips_regnum.dspacc = dspacc;
+              mips_regnum.dspctl = dspctl;
+            }
+        }
+
       /* It would be nice to detect an attempt to use a 64-bit ABI
          when only 32-bit registers are provided.  */
+      reg_names = NULL;
     }
 
   /* First of all, extract the elf_flags, if available.  */
   if (info.abfd && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour)
     elf_flags = elf_elfheader (info.abfd)->e_flags;
   else if (arches != NULL)
     elf_flags = gdbarch_tdep (arches->gdbarch)->elf_flags;
   else
     elf_flags = 0;
   if (gdbarch_debug)
@@ skipping 82 matching lines @@
   if (wanted_abi != MIPS_ABI_UNKNOWN)
     mips_abi = wanted_abi;
   else if (found_abi != MIPS_ABI_UNKNOWN)
     mips_abi = found_abi;
   else
     mips_abi = MIPS_ABI_O32;
   if (gdbarch_debug)
     fprintf_unfiltered (gdb_stdlog, "mips_gdbarch_init: mips_abi = %d\n",
                         mips_abi);
 
+  /* Determine the default compressed ISA.  */
+  if ((elf_flags & EF_MIPS_ARCH_ASE_MICROMIPS) != 0
+      && (elf_flags & EF_MIPS_ARCH_ASE_M16) == 0)
+    mips_isa = ISA_MICROMIPS;
+  else if ((elf_flags & EF_MIPS_ARCH_ASE_M16) != 0
+           && (elf_flags & EF_MIPS_ARCH_ASE_MICROMIPS) == 0)
+    mips_isa = ISA_MIPS16;
+  else
+    mips_isa = global_mips_compression ();
+  mips_compression_string = mips_compression_strings[mips_isa];
+
   /* Also used when doing an architecture lookup.  */
   if (gdbarch_debug)
     fprintf_unfiltered (gdb_stdlog,
                         "mips_gdbarch_init: "
                         "mips64_transfers_32bit_regs_p = %d\n",
                         mips64_transfers_32bit_regs_p);
 
   /* Determine the MIPS FPU type.  */
 #ifdef HAVE_ELF
   if (info.abfd
@@ skipping 85 matching lines @@
       return arches->gdbarch;
     }
 
   /* Need a new architecture.  Fill in a target specific vector.  */
   tdep = (struct gdbarch_tdep *) xmalloc (sizeof (struct gdbarch_tdep));
   gdbarch = gdbarch_alloc (&info, tdep);
   tdep->elf_flags = elf_flags;
   tdep->mips64_transfers_32bit_regs_p = mips64_transfers_32bit_regs_p;
   tdep->found_abi = found_abi;
   tdep->mips_abi = mips_abi;
+  tdep->mips_isa = mips_isa;
   tdep->mips_fpu_type = fpu_type;
   tdep->register_size_valid_p = 0;
   tdep->register_size = 0;
   tdep->gregset = NULL;
   tdep->gregset64 = NULL;
   tdep->fpregset = NULL;
   tdep->fpregset64 = NULL;
 
   if (info.target_desc)
     {
@@ skipping 21 matching lines @@
   set_gdbarch_pseudo_register_write (gdbarch, mips_pseudo_register_write);
 
   set_gdbarch_ax_pseudo_register_collect (gdbarch,
                                           mips_ax_pseudo_register_collect);
   set_gdbarch_ax_pseudo_register_push_stack
       (gdbarch, mips_ax_pseudo_register_push_stack);
 
   set_gdbarch_elf_make_msymbol_special (gdbarch,
                                         mips_elf_make_msymbol_special);
 
-  /* Fill in the OS dependant register numbers and names.  */
-  {
-    const char **reg_names;
-    struct mips_regnum *regnum = GDBARCH_OBSTACK_ZALLOC (gdbarch,
-                                                         struct mips_regnum);
-    if (tdesc_has_registers (info.target_desc))
-      {
-        regnum->lo = MIPS_EMBED_LO_REGNUM;
-        regnum->hi = MIPS_EMBED_HI_REGNUM;
-        regnum->badvaddr = MIPS_EMBED_BADVADDR_REGNUM;
-        regnum->cause = MIPS_EMBED_CAUSE_REGNUM;
-        regnum->pc = MIPS_EMBED_PC_REGNUM;
-        regnum->fp0 = MIPS_EMBED_FP0_REGNUM;
-        regnum->fp_control_status = 70;
-        regnum->fp_implementation_revision = 71;
-        num_regs = MIPS_LAST_EMBED_REGNUM + 1;
-        reg_names = NULL;
-      }
-    else if (info.osabi == GDB_OSABI_IRIX)
-      {
-        regnum->fp0 = 32;
-        regnum->pc = 64;
-        regnum->cause = 65;
-        regnum->badvaddr = 66;
-        regnum->hi = 67;
-        regnum->lo = 68;
-        regnum->fp_control_status = 69;
-        regnum->fp_implementation_revision = 70;
-        num_regs = 71;
-        reg_names = mips_irix_reg_names;
-      }
-    else
-      {
-        regnum->lo = MIPS_EMBED_LO_REGNUM;
-        regnum->hi = MIPS_EMBED_HI_REGNUM;
-        regnum->badvaddr = MIPS_EMBED_BADVADDR_REGNUM;
-        regnum->cause = MIPS_EMBED_CAUSE_REGNUM;
-        regnum->pc = MIPS_EMBED_PC_REGNUM;
-        regnum->fp0 = MIPS_EMBED_FP0_REGNUM;
-        regnum->fp_control_status = 70;
-        regnum->fp_implementation_revision = 71;
-        num_regs = 90;
-        if (info.bfd_arch_info != NULL
-            && info.bfd_arch_info->mach == bfd_mach_mips3900)
-          reg_names = mips_tx39_reg_names;
-        else
-          reg_names = mips_generic_reg_names;
-      }
-    /* FIXME: cagney/2003-11-15: For MIPS, hasn't gdbarch_pc_regnum been
-       replaced by gdbarch_read_pc?  */
-    set_gdbarch_pc_regnum (gdbarch, regnum->pc + num_regs);
-    set_gdbarch_sp_regnum (gdbarch, MIPS_SP_REGNUM + num_regs);
-    set_gdbarch_fp0_regnum (gdbarch, regnum->fp0);
-    set_gdbarch_num_regs (gdbarch, num_regs);
-    set_gdbarch_num_pseudo_regs (gdbarch, num_regs);
-    set_gdbarch_register_name (gdbarch, mips_register_name);
-    set_gdbarch_virtual_frame_pointer (gdbarch, mips_virtual_frame_pointer);
-    tdep->mips_processor_reg_names = reg_names;
-    tdep->regnum = regnum;
-  }
+  regnum = GDBARCH_OBSTACK_ZALLOC (gdbarch, struct mips_regnum);
+  *regnum = mips_regnum;
+  set_gdbarch_fp0_regnum (gdbarch, regnum->fp0);
+  set_gdbarch_num_regs (gdbarch, num_regs);
+  set_gdbarch_num_pseudo_regs (gdbarch, num_regs);
+  set_gdbarch_register_name (gdbarch, mips_register_name);
+  set_gdbarch_virtual_frame_pointer (gdbarch, mips_virtual_frame_pointer);
+  tdep->mips_processor_reg_names = reg_names;
+  tdep->regnum = regnum;
 
   switch (mips_abi)
     {
     case MIPS_ABI_O32:
       set_gdbarch_push_dummy_call (gdbarch, mips_o32_push_dummy_call);
       set_gdbarch_return_value (gdbarch, mips_o32_return_value);
       tdep->mips_last_arg_regnum = MIPS_A0_REGNUM + 4 - 1;
       tdep->mips_last_fp_arg_regnum = tdep->regnum->fp0 + 12 + 4 - 1;
       tdep->default_mask_address_p = 0;
       set_gdbarch_long_bit (gdbarch, 32);
@@ skipping 145 matching lines @@
   /* Map debug register numbers onto internal register numbers.  */
   set_gdbarch_stab_reg_to_regnum (gdbarch, mips_stab_reg_to_regnum);
   set_gdbarch_ecoff_reg_to_regnum (gdbarch,
                                    mips_dwarf_dwarf2_ecoff_reg_to_regnum);
   set_gdbarch_dwarf2_reg_to_regnum (gdbarch,
                                     mips_dwarf_dwarf2_ecoff_reg_to_regnum);
   set_gdbarch_register_sim_regno (gdbarch, mips_register_sim_regno);
 
   /* MIPS version of CALL_DUMMY.  */
 
-  /* NOTE: cagney/2003-08-05: Eventually call dummy location will be
-     replaced by a command, and all targets will default to on stack
-     (regardless of the stack's execute status).  */
-  set_gdbarch_call_dummy_location (gdbarch, AT_SYMBOL);
+  set_gdbarch_call_dummy_location (gdbarch, ON_STACK);
+  set_gdbarch_push_dummy_code (gdbarch, mips_push_dummy_code);
   set_gdbarch_frame_align (gdbarch, mips_frame_align);
 
   set_gdbarch_convert_register_p (gdbarch, mips_convert_register_p);
   set_gdbarch_register_to_value (gdbarch, mips_register_to_value);
   set_gdbarch_value_to_register (gdbarch, mips_value_to_register);
 
   set_gdbarch_inner_than (gdbarch, core_addr_lessthan);
   set_gdbarch_breakpoint_from_pc (gdbarch, mips_breakpoint_from_pc);
+  set_gdbarch_remote_breakpoint_from_pc (gdbarch,
+                                         mips_remote_breakpoint_from_pc);
+  set_gdbarch_adjust_breakpoint_address (gdbarch,
+                                         mips_adjust_breakpoint_address);
 
   set_gdbarch_skip_prologue (gdbarch, mips_skip_prologue);
 
   set_gdbarch_in_function_epilogue_p (gdbarch, mips_in_function_epilogue_p);
 
   set_gdbarch_pointer_to_address (gdbarch, signed_pointer_to_address);
   set_gdbarch_address_to_pointer (gdbarch, address_to_signed_pointer);
   set_gdbarch_integer_to_address (gdbarch, mips_integer_to_address);
 
   set_gdbarch_register_type (gdbarch, mips_register_type);
@@ skipping 10 matching lines @@
   /* FIXME: cagney/2003-08-29: The macros target_have_steppable_watchpoint,
      HAVE_NONSTEPPABLE_WATCHPOINT, and target_have_continuable_watchpoint
      need to all be folded into the target vector.  Since they are
      being used as guards for target_stopped_by_watchpoint, why not have
      target_stopped_by_watchpoint return the type of watchpoint that the code
      is sitting on?  */
   set_gdbarch_have_nonsteppable_watchpoint (gdbarch, 1);
 
   set_gdbarch_skip_trampoline_code (gdbarch, mips_skip_trampoline_code);
 
+  /* NOTE drow/2012-04-25: We overload the core solib trampoline code
+     to support MIPS16.  This is a bad thing.  Make sure not to do it
+     if we have an OS ABI that actually supports shared libraries, since
+     shared library support is more important.  If we have an OS someday
+     that supports both shared libraries and MIPS16, we'll have to find
+     a better place for these.
+     macro/2012-04-25: But that applies to return trampolines only and
+     currently no MIPS OS ABI uses shared libraries that have them.  */
+  set_gdbarch_in_solib_return_trampoline (gdbarch, mips_in_return_stub);
+
   set_gdbarch_single_step_through_delay (gdbarch,
                                          mips_single_step_through_delay);
 
   /* Virtual tables.  */
   set_gdbarch_vbit_in_delta (gdbarch, 1);
 
   mips_register_g_packet_guesses (gdbarch);
 
   /* Hook in OS ABI-specific overrides, if they have been registered.  */
   info.tdep_info = (void *) tdesc_data;
   gdbarch_init_osabi (info, gdbarch);
 
+  /* The hook may have adjusted num_regs, fetch the final value and
+     set pc_regnum and sp_regnum now that it has been fixed.  */
+  num_regs = gdbarch_num_regs (gdbarch);
+  set_gdbarch_pc_regnum (gdbarch, regnum->pc + num_regs);
+  set_gdbarch_sp_regnum (gdbarch, MIPS_SP_REGNUM + num_regs);
+
   /* Unwind the frame.  */
   dwarf2_append_unwinders (gdbarch);
   frame_unwind_append_unwinder (gdbarch, &mips_stub_frame_unwind);
   frame_unwind_append_unwinder (gdbarch, &mips_insn16_frame_unwind);
+  frame_unwind_append_unwinder (gdbarch, &mips_micro_frame_unwind);
   frame_unwind_append_unwinder (gdbarch, &mips_insn32_frame_unwind);
   frame_base_append_sniffer (gdbarch, dwarf2_frame_base_sniffer);
   frame_base_append_sniffer (gdbarch, mips_stub_frame_base_sniffer);
   frame_base_append_sniffer (gdbarch, mips_insn16_frame_base_sniffer);
+  frame_base_append_sniffer (gdbarch, mips_micro_frame_base_sniffer);
   frame_base_append_sniffer (gdbarch, mips_insn32_frame_base_sniffer);
 
   if (tdesc_data)
     {
       set_tdesc_pseudo_register_type (gdbarch, mips_pseudo_register_type);
       tdesc_use_registers (gdbarch, info.target_desc, tdesc_data);
 
       /* Override the normal target description methods to handle our
          dual real and pseudo registers.  */
       set_gdbarch_register_name (gdbarch, mips_register_name);
@@ skipping 73 matching lines @@
         {
           /* Probably shouldn't happen...  */
           fprintf_filtered (file,
                             "The (auto detected) MIPS ABI \"%s\" is in use "
                             "even though the user setting was \"%s\".\n",
              actual_abi_str, mips_abi_strings[global_abi]);
         }
     }
 }
 
+/* Print out which MIPS compressed ISA encoding is used.  */
+
+static void
+show_mips_compression (struct ui_file *file, int from_tty,
+                       struct cmd_list_element *c, const char *value)
+{
+  fprintf_filtered (file, _("The compressed ISA encoding used is %s.\n"),
+                    value);
+}
+
 static void
 mips_dump_tdep (struct gdbarch *gdbarch, struct ui_file *file)
 {
   struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
   if (tdep != NULL)
     {
       int ef_mips_arch;
       int ef_mips_32bitmode;
       /* Determine the ISA.  */
       switch (tdep->elf_flags & EF_MIPS_ARCH)
@@ skipping 96 matching lines @@
   o32\n\
   o64\n\
   n32\n\
   n64\n\
   eabi32\n\
   eabi64"),
                         mips_abi_update,
                         show_mips_abi,
                         &setmipscmdlist, &showmipscmdlist);
 
+  /* Allow the user to set the ISA to assume for compressed code if ELF
+     file flags don't tell or there is no program file selected.  This
+     setting is updated whenever unambiguous ELF file flags are interpreted,
+     and carried over to subsequent sessions.  */
+  add_setshow_enum_cmd ("compression", class_obscure, mips_compression_strings,
+                        &mips_compression_string, _("\
+Set the compressed ISA encoding used by MIPS code."), _("\
+Show the compressed ISA encoding used by MIPS code."), _("\
+Select the compressed ISA encoding used in functions that have no symbol\n\
+information available.  The encoding can be set to either of:\n\
+  mips16\n\
+  micromips\n\
+and is updated automatically from ELF file flags if available."),
+                        mips_abi_update,
+                        show_mips_compression,
+                        &setmipscmdlist, &showmipscmdlist);
+
   /* Let the user turn off floating point and set the fence post for
      heuristic_proc_start.  */
 
   add_prefix_cmd ("mipsfpu", class_support, set_mipsfpu_command,
                   _("Set use of MIPS floating-point coprocessor."),
                   &mipsfpulist, "set mipsfpu ", 0, &setlist);
   add_cmd ("single", class_support, set_mipsfpu_single_command,
            _("Select single-precision MIPS floating-point coprocessor."),
            &mipsfpulist);
   add_cmd ("double", class_support, set_mipsfpu_double_command,
@@ skipping 61 matching lines @@
   add_setshow_zinteger_cmd ("mips", class_maintenance,
                             &mips_debug, _("\
 Set mips debugging."), _("\
 Show mips debugging."), _("\
 When non-zero, mips specific debugging is enabled."),
                             NULL,
                             NULL, /* FIXME: i18n: Mips debugging is
                                      currently %s.  */
                             &setdebuglist, &showdebuglist);
 }