[turbofan] Add support for reinterpreting integers as floating point and vice versa.

src/compiler/ia32/code-generator-ia32.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/compiler/code-generator.h"
 
 #include "src/compiler/code-generator-impl.h"
 #include "src/compiler/gap-resolver.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/osr.h"
@@ skipping 822 matching lines @@
       break;
     case kIA32Movss:
       if (instr->HasOutput()) {
         __ movss(i.OutputDoubleRegister(), i.MemoryOperand());
       } else {
         size_t index = 0;
         Operand operand = i.MemoryOperand(&index);
         __ movss(operand, i.InputDoubleRegister(index));
       }
       break;
+    case kIA32BitcastFI:
+      if (instr->InputAt(0)->IsDoubleStackSlot()) {
+        __ mov(i.OutputRegister(), i.InputOperand(0));
+      } else {
+        __ movd(i.OutputRegister(), i.InputDoubleRegister(0));
+      }
+      break;
+    case kIA32BitcastIF:
+      if (instr->InputAt(0)->IsRegister()) {
+        __ movd(i.OutputDoubleRegister(), i.InputRegister(0));
+      } else {
+        __ movss(i.OutputDoubleRegister(), i.InputOperand(0));
+      }
+      break;
     case kIA32Lea: {
       AddressingMode mode = AddressingModeField::decode(instr->opcode());
       // Shorten "leal" to "addl", "subl" or "shll" if the register allocation
       // and addressing mode just happens to work out. The "addl"/"subl" forms
       // in these cases are faster based on measurements.
       if (mode == kMode_MI) {
         __ Move(i.OutputRegister(), Immediate(i.InputInt32(0)));
       } else if (i.InputRegister(0).is(i.OutputRegister())) {
         if (mode == kMode_MRI) {
           int32_t constant_summand = i.InputInt32(1);
@@ skipping 681 matching lines @@
     int padding_size = last_lazy_deopt_pc_ + space_needed - current_pc;
     __ Nop(padding_size);
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8