ARM: Fix a number of issues with running without VFPv3 support

src/arm/simulator-arm.cc

 // Copyright 2011 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 49 matching lines @@
   void Debug();
 
  private:
   static const Instr kBreakpointInstr =
       (al | (7*B25) | (1*B24) | kBreakpoint);
   static const Instr kNopInstr = (al | (13*B21));
 
   Simulator* sim_;
 
   int32_t GetRegisterValue(int regnum);
+  double GetRegisterPairDoubleValue(int regnum);
   double GetVFPDoubleRegisterValue(int regnum);
   bool GetValue(const char* desc, int32_t* value);
   bool GetVFPSingleValue(const char* desc, float* value);
   bool GetVFPDoubleValue(const char* desc, double* value);
 
   // Set or delete a breakpoint. Returns true if successful.
   bool SetBreakpoint(Instruction* breakpc);
   bool DeleteBreakpoint(Instruction* breakpc);
 
   // Undo and redo all breakpoints. This is needed to bracket disassembly and
@@ skipping 81 matching lines @@
 
 int32_t ArmDebugger::GetRegisterValue(int regnum) {
   if (regnum == kPCRegister) {
     return sim_->get_pc();
   } else {
     return sim_->get_register(regnum);
   }
 }
 
 
+double ArmDebugger::GetRegisterPairDoubleValue(int regnum) {
+  return sim_->get_double_from_register_pair(regnum);
+}
+
+
 double ArmDebugger::GetVFPDoubleRegisterValue(int regnum) {
   return sim_->get_double_from_d_register(regnum);
 }
 
 
 bool ArmDebugger::GetValue(const char* desc, int32_t* value) {
   int regnum = Registers::Number(desc);
   if (regnum != kNoRegister) {
     *value = GetRegisterValue(regnum);
     return true;
@@ skipping 117 matching lines @@
                         "%" XSTR(ARG_SIZE) "s",
                         cmd, arg1, arg2);
       if ((strcmp(cmd, "si") == 0) || (strcmp(cmd, "stepi") == 0)) {
         sim_->InstructionDecode(reinterpret_cast<Instruction*>(sim_->get_pc()));
       } else if ((strcmp(cmd, "c") == 0) || (strcmp(cmd, "cont") == 0)) {
         // Execute the one instruction we broke at with breakpoints disabled.
         sim_->InstructionDecode(reinterpret_cast<Instruction*>(sim_->get_pc()));
         // Leave the debugger shell.
         done = true;
       } else if ((strcmp(cmd, "p") == 0) || (strcmp(cmd, "print") == 0)) {
-        if (argc == 2) {
+        if (argc == 2 || (argc == 3 && strcmp(arg2, "fp") == 0)) {
           int32_t value;
           float svalue;
           double dvalue;
           if (strcmp(arg1, "all") == 0) {
             for (int i = 0; i < kNumRegisters; i++) {
               value = GetRegisterValue(i);
-              PrintF("%3s: 0x%08x %10d\n", Registers::Name(i), value, value);
+              PrintF("%3s: 0x%08x %10d", Registers::Name(i), value, value);
+              if ((argc == 3 && strcmp(arg2, "fp") == 0) &&
+                  i < 8 &&
+                  (i % 2) == 0) {
+                dvalue = GetRegisterPairDoubleValue(i);
+                PrintF(" (%f)\n", dvalue);
+              } else {
+                PrintF("\n");
+              }
             }
             for (int i = 0; i < kNumVFPDoubleRegisters; i++) {
               dvalue = GetVFPDoubleRegisterValue(i);
               uint64_t as_words = BitCast<uint64_t>(dvalue);
               PrintF("%3s: %f 0x%08x %08x\n",
                      VFPRegisters::Name(i, true),
                      dvalue,
                      static_cast<uint32_t>(as_words >> 32),
                      static_cast<uint32_t>(as_words & 0xffffffff));
             }
@@ skipping 217 matching lines @@
         PrintF("Trace of executed instructions is %s\n",
                ::v8::internal::FLAG_trace_sim ? "on" : "off");
       } else if ((strcmp(cmd, "h") == 0) || (strcmp(cmd, "help") == 0)) {
         PrintF("cont\n");
         PrintF("  continue execution (alias 'c')\n");
         PrintF("stepi\n");
         PrintF("  step one instruction (alias 'si')\n");
         PrintF("print <register>\n");
         PrintF("  print register content (alias 'p')\n");
         PrintF("  use register name 'all' to print all registers\n");
+        PrintF("  add argument 'fp' to print register pair double values\n");
         PrintF("printobject <register>\n");
         PrintF("  print an object from a register (alias 'po')\n");
         PrintF("flags\n");
         PrintF("  print flags\n");
         PrintF("stack [<words>]\n");
         PrintF("  dump stack content, default dump 10 words)\n");
         PrintF("mem <address> [<words>]\n");
         PrintF("  dump memory content, default dump 10 words)\n");
         PrintF("disasm [<instructions>]\n");
         PrintF("disasm [<address/register>]\n");
@@ skipping 303 matching lines @@
 int32_t Simulator::get_register(int reg) const {
   ASSERT((reg >= 0) && (reg < num_registers));
   // Stupid code added to avoid bug in GCC.
   // See: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=43949
   if (reg >= num_registers) return 0;
   // End stupid code.
   return registers_[reg] + ((reg == pc) ? Instruction::kPCReadOffset : 0);
 }
 
 
+double Simulator::get_double_from_register_pair(int reg) {
+  ASSERT((reg >= 0) && (reg < num_registers) && ((reg % 2) == 0));
+
+  double dm_val = 0.0;
+  // Read the bits from the unsigned integer register_[] array
+  // into the double precision floating point value and return it.
+  char buffer[2 * sizeof(vfp_register[0])];
+  memcpy(buffer, &registers_[reg], 2 * sizeof(registers_[0]));
+  memcpy(&dm_val, buffer, 2 * sizeof(registers_[0]));
+  return(dm_val);
+}
+
+
 void Simulator::set_dw_register(int dreg, const int* dbl) {
   ASSERT((dreg >= 0) && (dreg < num_d_registers));
   registers_[dreg] = dbl[0];
   registers_[dreg + 1] = dbl[1];
 }
 
 
 // Raw access to the PC register.
 void Simulator::set_pc(int32_t value) {
   pc_modified_ = true;
@@ skipping 2383 matching lines @@
   uintptr_t address = *stack_slot;
   set_register(sp, current_sp + sizeof(uintptr_t));
   return address;
 }
 
 } }  // namespace v8::internal
 
 #endif  // USE_SIMULATOR
 
 #endif  // V8_TARGET_ARCH_ARM