[strong] Disallow implicit conversions for comparison

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 1451 matching lines @@
 
   void PrintBaseName(std::ostream& os) const override;  // NOLINT
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(StringAdd);
   DEFINE_HYDROGEN_CODE_STUB(StringAdd, HydrogenCodeStub);
 };
 
 
 class CompareICStub : public PlatformCodeStub {
  public:
-  CompareICStub(Isolate* isolate, Token::Value op, CompareICState::State left,
-                CompareICState::State right, CompareICState::State state)
+  CompareICStub(Isolate* isolate, Token::Value op, bool strong,
+                CompareICState::State left, CompareICState::State right,
+                CompareICState::State state)
       : PlatformCodeStub(isolate) {
     DCHECK(Token::IsCompareOp(op));
-    minor_key_ = OpBits::encode(op - Token::EQ) | LeftStateBits::encode(left) |
-                 RightStateBits::encode(right) | StateBits::encode(state);
+    minor_key_ = OpBits::encode(op - Token::EQ) | StrongBits::encode(strong) |
+                 LeftStateBits::encode(left) | RightStateBits::encode(right) |
+                 StateBits::encode(state);
   }
 
   void set_known_map(Handle<Map> map) { known_map_ = map; }
 
   InlineCacheState GetICState() const override;
 
   Token::Value op() const {
     return static_cast<Token::Value>(Token::EQ + OpBits::decode(minor_key_));
   }
 
+  bool strong() const { return StrongBits::decode(minor_key_); }
+
   CompareICState::State left() const {
     return LeftStateBits::decode(minor_key_);
   }
   CompareICState::State right() const {
     return RightStateBits::decode(minor_key_);
   }
   CompareICState::State state() const { return StateBits::decode(minor_key_); }
 
  private:
   Code::Kind GetCodeKind() const override { return Code::COMPARE_IC; }
@@ skipping 11 matching lines @@
   bool strict() const { return op() == Token::EQ_STRICT; }
   Condition GetCondition() const;
 
   void AddToSpecialCache(Handle<Code> new_object) override;
   bool FindCodeInSpecialCache(Code** code_out) override;
   bool UseSpecialCache() override {
     return state() == CompareICState::KNOWN_OBJECT;
   }
 
   class OpBits : public BitField<int, 0, 3> {};
-  class LeftStateBits : public BitField<CompareICState::State, 3, 4> {};
-  class RightStateBits : public BitField<CompareICState::State, 7, 4> {};
-  class StateBits : public BitField<CompareICState::State, 11, 4> {};
+  class StrongBits : public BitField<bool, 3, 1> {};
+  class LeftStateBits : public BitField<CompareICState::State, 4, 4> {};
+  class RightStateBits : public BitField<CompareICState::State, 8, 4> {};
+  class StateBits : public BitField<CompareICState::State, 12, 4> {};
 
   Handle<Map> known_map_;
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(BinaryOp);
   DEFINE_PLATFORM_CODE_STUB(CompareIC, PlatformCodeStub);
 };
 
 
 class CompareNilICStub : public HydrogenCodeStub  {
  public:
@@ skipping 1303 matching lines @@
 
 #undef DEFINE_CALL_INTERFACE_DESCRIPTOR
 #undef DEFINE_PLATFORM_CODE_STUB
 #undef DEFINE_HANDLER_CODE_STUB
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_