[crankshaft] Re-add fast-case for string add left/right.

src/code-stubs.h

 // Copyright 2012 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_CODE_STUBS_H_
 #define V8_CODE_STUBS_H_
 
 #include "src/allocation.h"
 #include "src/assembler.h"
 #include "src/codegen.h"
@@ skipping 658 matching lines @@
 
 
 enum StringAddFlags {
   // Omit both parameter checks.
   STRING_ADD_CHECK_NONE = 0,
   // Check left parameter.
   STRING_ADD_CHECK_LEFT = 1 << 0,
   // Check right parameter.
   STRING_ADD_CHECK_RIGHT = 1 << 1,
   // Check both parameters.
-  STRING_ADD_CHECK_BOTH = STRING_ADD_CHECK_LEFT | STRING_ADD_CHECK_RIGHT
+  STRING_ADD_CHECK_BOTH = STRING_ADD_CHECK_LEFT | STRING_ADD_CHECK_RIGHT,
+  // Convert parameters when check fails (instead of throwing an exception).
+  STRING_ADD_CONVERT = 1 << 2,
+  STRING_ADD_CONVERT_LEFT = STRING_ADD_CHECK_LEFT | STRING_ADD_CONVERT,
+  STRING_ADD_CONVERT_RIGHT = STRING_ADD_CHECK_RIGHT | STRING_ADD_CONVERT
 };
 
 
 std::ostream& operator<<(std::ostream& os, const StringAddFlags& flags);
 
 
 class StringAddTFStub : public TurboFanCodeStub {
  public:
   StringAddTFStub(Isolate* isolate, StringAddFlags flags,
                   PretenureFlag pretenure_flag)
       : TurboFanCodeStub(isolate) {
     minor_key_ = StringAddFlagsBits::encode(flags) |
                  PretenureFlagBits::encode(pretenure_flag);
   }
 
   StringAddFlags flags() const {
     return StringAddFlagsBits::decode(MinorKey());
   }
 
   PretenureFlag pretenure_flag() const {
     return PretenureFlagBits::decode(MinorKey());
   }
 
  private:
-  class StringAddFlagsBits : public BitField<StringAddFlags, 0, 2> {};
-  class PretenureFlagBits : public BitField<PretenureFlag, 2, 1> {};
+  class StringAddFlagsBits : public BitField<StringAddFlags, 0, 3> {};
+  class PretenureFlagBits : public BitField<PretenureFlag, 3, 1> {};
 
   void PrintBaseName(std::ostream& os) const override;  // NOLINT
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(StringAdd);
   DEFINE_CODE_STUB(StringAddTF, TurboFanCodeStub);
 };
 
 
 class NumberToStringStub final : public HydrogenCodeStub {
  public:
@@ skipping 924 matching lines @@
 
   PretenureFlag pretenure_flag() const {
     return PretenureFlagBits::decode(sub_minor_key());
   }
 
   // Parameters accessed via CodeStubGraphBuilder::GetParameter()
   static const int kLeft = 0;
   static const int kRight = 1;
 
  private:
-  class StringAddFlagsBits: public BitField<StringAddFlags, 0, 2> {};
-  class PretenureFlagBits: public BitField<PretenureFlag, 2, 1> {};
+  class StringAddFlagsBits : public BitField<StringAddFlags, 0, 3> {};
+  class PretenureFlagBits : public BitField<PretenureFlag, 3, 1> {};
 
   void PrintBaseName(std::ostream& os) const override;  // NOLINT
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(StringAdd);
   DEFINE_HYDROGEN_CODE_STUB(StringAdd, HydrogenCodeStub);
 };
 
 
 class CompareICStub : public PlatformCodeStub {
  public:
@@ skipping 1413 matching lines @@
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 
 extern Representation RepresentationFromType(Type* type);
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODE_STUBS_H_