A64: Introduce 'branch types' that extend the architectural conditions.

src/a64/macro-assembler-a64.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 46 matching lines @@
 inline MemOperand FieldMemOperand(Register object, int offset);
 inline MemOperand UntagSmiFieldMemOperand(Register object, int offset);
 
 // Generate a MemOperand for loading a SMI from memory.
 inline MemOperand UntagSmiMemOperand(Register object, int offset);
 
 
 // ----------------------------------------------------------------------------
 // MacroAssembler
 
+enum BranchType {
+  // Copies of architectural conditions.
+  // The associated conditions can be used in place of those, the code will
+  // take care of reinterpreting them with the correct type.
+  integer_eq = eq,
+  integer_ne = ne,
+  integer_hs = hs,
+  integer_lo = lo,
+  integer_mi = mi,
+  integer_pl = pl,
+  integer_vs = vs,
+  integer_vc = vc,
+  integer_hi = hi,
+  integer_ls = ls,
+  integer_ge = ge,
+  integer_lt = lt,
+  integer_gt = gt,
+  integer_le = le,
+  integer_al = al,
+  integer_nv = nv,
+
+  // These two are *different* from the architectural codes al and nv.
+  // 'always' is used to generate unconditional branches.
+  // 'never' is used to not generate a branch (generally as the inverse
+  // branch type of 'always).
+  always, never,
+  // cbz and cbnz
+  reg_zero, reg_not_zero,
+  // tbz and tbnz
+  reg_bit_clear, reg_bit_set,
+
+  // Aliases.
+  kBranchTypeFirstCondition = eq,
+  kBranchTypeLastCondition = nv,
+  kBranchTypeFirstUsingReg = reg_zero,
+  kBranchTypeFirstUsingBit = reg_bit_clear
+};
+
+inline BranchType InvertBranchType(BranchType type) {
+  if (kBranchTypeFirstCondition <= type && type <= kBranchTypeLastCondition) {
+    return static_cast<BranchType>(
+        InvertCondition(static_cast<Condition>(type)));
+  } else {
+    return static_cast<BranchType>(type ^ 1);
+  }
+}
+
 enum RememberedSetAction { EMIT_REMEMBERED_SET, OMIT_REMEMBERED_SET };
 enum SmiCheck { INLINE_SMI_CHECK, OMIT_SMI_CHECK };
 enum LinkRegisterStatus { kLRHasNotBeenSaved, kLRHasBeenSaved };
 enum TargetAddressStorageMode {
   CAN_INLINE_TARGET_ADDRESS,
   NEVER_INLINE_TARGET_ADDRESS
 };
 enum UntagMode { kNotSpeculativeUntag, kSpeculativeUntag };
 enum ArrayHasHoles { kArrayCantHaveHoles, kArrayCanHaveHoles };
 enum CopyHint { kCopyUnknown, kCopyShort, kCopyLong };
@@ skipping 128 matching lines @@
                       LoadStoreOp op);
 
   // V8-specific load/store helpers.
   void Load(const Register& rt, const MemOperand& addr, Representation r);
   void Store(const Register& rt, const MemOperand& addr, Representation r);
 
   // Remaining instructions are simple pass-through calls to the assembler.
   inline void Adr(const Register& rd, Label* label);
   inline void Asr(const Register& rd, const Register& rn, unsigned shift);
   inline void Asr(const Register& rd, const Register& rn, const Register& rm);
+
+  // Branch type inversion relies on these relations.
+  STATIC_ASSERT((reg_zero      == (reg_not_zero ^ 1)) &&
+                (reg_bit_clear == (reg_bit_set ^ 1)) &&
+                (always        == (never ^ 1)));
+
+  void B(Label* label, BranchType type, Register reg = NoReg, int bit = -1);
+
   inline void B(Label* label);
   inline void B(Condition cond, Label* label);
   void B(Label* label, Condition cond);
   inline void Bfi(const Register& rd,
                   const Register& rn,
                   unsigned lsb,
                   unsigned width);
   inline void Bfxil(const Register& rd,
                     const Register& rn,
                     unsigned lsb,
@@ skipping 2035 matching lines @@
 #error "Unsupported option"
 #define CODE_COVERAGE_STRINGIFY(x) #x
 #define CODE_COVERAGE_TOSTRING(x) CODE_COVERAGE_STRINGIFY(x)
 #define __FILE_LINE__ __FILE__ ":" CODE_COVERAGE_TOSTRING(__LINE__)
 #define ACCESS_MASM(masm) masm->stop(__FILE_LINE__); masm->
 #else
 #define ACCESS_MASM(masm) masm->
 #endif
 
 #endif  // V8_A64_MACRO_ASSEMBLER_A64_H_