Remove the obsolete OverwriteMode optimization.

src/x64/full-codegen-x64.cc

 // 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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
@@ skipping 1979 matching lines @@
           EmitKeyedPropertyLoad(property);
           PrepareForBailoutForId(property->LoadId(), TOS_REG);
           break;
       }
     }
 
     Token::Value op = expr->binary_op();
     __ Push(rax);  // Left operand goes on the stack.
     VisitForAccumulatorValue(expr->value());
 
-    OverwriteMode mode = expr->value()->ResultOverwriteAllowed()
-        ? OVERWRITE_RIGHT
-        : NO_OVERWRITE;
     SetSourcePosition(expr->position() + 1);
     AccumulatorValueContext context(this);
     if (ShouldInlineSmiCase(op)) {
       EmitInlineSmiBinaryOp(expr->binary_operation(),
                             op,
-                            mode,
                             expr->target(),
                             expr->value());
     } else {
-      EmitBinaryOp(expr->binary_operation(), op, mode);
+      EmitBinaryOp(expr->binary_operation(), op);
     }
     // Deoptimization point in case the binary operation may have side effects.
     PrepareForBailout(expr->binary_operation(), TOS_REG);
   } else {
     VisitForAccumulatorValue(expr->value());
   }
 
   // Record source position before possible IC call.
   SetSourcePosition(expr->position());
 
@@ skipping 359 matching lines @@
 void FullCodeGenerator::EmitKeyedSuperPropertyLoad(Property* prop) {
   // Stack: receiver, home_object, key.
   SetSourcePosition(prop->position());
 
   __ CallRuntime(Runtime::kLoadKeyedFromSuper, 3);
 }
 
 
 void FullCodeGenerator::EmitInlineSmiBinaryOp(BinaryOperation* expr,
                                               Token::Value op,
-                                              OverwriteMode mode,
                                               Expression* left,
                                               Expression* right) {
   // Do combined smi check of the operands. Left operand is on the
   // stack (popped into rdx). Right operand is in rax but moved into
   // rcx to make the shifts easier.
   Label done, stub_call, smi_case;
   __ Pop(rdx);
   __ movp(rcx, rax);
   __ orp(rax, rdx);
   JumpPatchSite patch_site(masm_);
   patch_site.EmitJumpIfSmi(rax, &smi_case, Label::kNear);
 
   __ bind(&stub_call);
   __ movp(rax, rcx);
-  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op, mode).code();
+  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op).code();
   CallIC(code, expr->BinaryOperationFeedbackId());
   patch_site.EmitPatchInfo();
   __ jmp(&done, Label::kNear);
 
   __ bind(&smi_case);
   switch (op) {
     case Token::SAR:
       __ SmiShiftArithmeticRight(rax, rdx, rcx);
       break;
     case Token::SHL:
@@ skipping 79 matching lines @@
   }
 
   // prototype
   __ CallRuntime(Runtime::kToFastProperties, 1);
 
   // constructor
   __ CallRuntime(Runtime::kToFastProperties, 1);
 }
 
 
-void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr,
-                                     Token::Value op,
-                                     OverwriteMode mode) {
+void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr, Token::Value op) {
   __ Pop(rdx);
-  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op, mode).code();
+  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op).code();
   JumpPatchSite patch_site(masm_);    // unbound, signals no inlined smi code.
   CallIC(code, expr->BinaryOperationFeedbackId());
   patch_site.EmitPatchInfo();
   context()->Plug(rax);
 }
 
 
 void FullCodeGenerator::EmitAssignment(Expression* expr) {
   DCHECK(expr->IsValidReferenceExpression());
 
@@ skipping 2270 matching lines @@
     }
   }
 
   // Record position before stub call.
   SetSourcePosition(expr->position());
 
   // Call stub for +1/-1.
   __ bind(&stub_call);
   __ movp(rdx, rax);
   __ Move(rax, Smi::FromInt(1));
-  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), expr->binary_op(),
-                                              NO_OVERWRITE).code();
+  Handle<Code> code =
+      CodeFactory::BinaryOpIC(isolate(), expr->binary_op()).code();
   CallIC(code, expr->CountBinOpFeedbackId());
   patch_site.EmitPatchInfo();
   __ bind(&done);
 
   // Store the value returned in rax.
   switch (assign_type) {
     case VARIABLE:
       if (expr->is_postfix()) {
         // Perform the assignment as if via '='.
         { EffectContext context(this);
@@ skipping 508 matching lines @@
   DCHECK_EQ(isolate->builtins()->OsrAfterStackCheck()->entry(),
             Assembler::target_address_at(call_target_address,
                                          unoptimized_code));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64