[turbofan] Introduces the BitcastWordToTaggedSigned and BitcastTaggedToWord opcodes.

src/compiler/code-assembler.h

 // Copyright 2015 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.
 
 #ifndef V8_COMPILER_CODE_ASSEMBLER_H_
 #define V8_COMPILER_CODE_ASSEMBLER_H_
 
 #include <map>
 #include <memory>
 
@@ skipping 117 matching lines @@
   V(Float64Log10)                       \
   V(Float64Cbrt)                        \
   V(Float64Neg)                         \
   V(Float64Sin)                         \
   V(Float64Sinh)                        \
   V(Float64Sqrt)                        \
   V(Float64Tan)                         \
   V(Float64Tanh)                        \
   V(Float64ExtractLowWord32)            \
   V(Float64ExtractHighWord32)           \
+  V(BitcastTaggedToWord)                \
   V(BitcastWordToTagged)                \
+  V(BitcastWordToTaggedSigned)          \
   V(TruncateFloat64ToFloat32)           \
   V(TruncateFloat64ToWord32)            \
   V(TruncateInt64ToInt32)               \
   V(ChangeFloat32ToFloat64)             \
   V(ChangeFloat64ToUint32)              \
   V(ChangeInt32ToFloat64)               \
   V(ChangeInt32ToInt64)                 \
   V(ChangeUint32ToFloat64)              \
   V(ChangeUint32ToUint64)               \
   V(RoundFloat64ToInt32)                \
@@ skipping 357 matching lines @@
   // Map of variables to the list of value nodes that have been added from each
   // merge path in their order of merging.
   std::map<Variable::Impl*, std::vector<Node*>> variable_merges_;
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_CODE_ASSEMBLER_H_