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

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

 // Copyright 2014 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 1058 matching lines @@
     case kPPC_DoubleConstruct:
 #if V8_TARGET_ARCH_PPC64
       __ MovInt64ComponentsToDouble(i.OutputDoubleRegister(),
                                     i.InputRegister(0), i.InputRegister(1), r0);
 #else
       __ MovInt64ToDouble(i.OutputDoubleRegister(), i.InputRegister(0),
                           i.InputRegister(1));
 #endif
       DCHECK_EQ(LeaveRC, i.OutputRCBit());
       break;
+#if V8_TARGET_ARCH_PPC64
+    case kPPC_BitcastDL:
+      __ mffprd(i.OutputRegister(), i.InputDoubleRegister(0));
+      break;
+    case kPPC_BitcastLD:
+      __ mtfprd(i.OutputDoubleRegister(), i.InputRegister(0));
+      break;
+#endif
     case kPPC_LoadWordU8:
       ASSEMBLE_LOAD_INTEGER(lbz, lbzx);
       break;
     case kPPC_LoadWordS8:
       ASSEMBLE_LOAD_INTEGER(lbz, lbzx);
       __ extsb(i.OutputRegister(), i.OutputRegister());
       break;
     case kPPC_LoadWordU16:
       ASSEMBLE_LOAD_INTEGER(lhz, lhzx);
       break;
@@ skipping 537 matching lines @@
       padding_size -= v8::internal::Assembler::kInstrSize;
     }
   }
 }
 
 #undef __
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8