Remove the obsolete OverwriteMode optimization.

src/arm64/full-codegen-arm64.cc

 // Copyright 2013 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_ARM64
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
@@ skipping 2000 matching lines @@
           EmitKeyedPropertyLoad(property);
           PrepareForBailoutForId(property->LoadId(), TOS_REG);
           break;
       }
     }
 
     Token::Value op = expr->binary_op();
     __ Push(x0);  // 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 69 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_expr,
                                               Expression* right_expr) {
   Label done, both_smis, stub_call;
 
   // Get the arguments.
   Register left = x1;
   Register right = x0;
   Register result = x0;
   __ Pop(left);
 
   // Perform combined smi check on both operands.
   __ Orr(x10, left, right);
   JumpPatchSite patch_site(masm_);
   patch_site.EmitJumpIfSmi(x10, &both_smis);
 
   __ Bind(&stub_call);
 
-  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op, mode).code();
+  Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), op).code();
   {
     Assembler::BlockPoolsScope scope(masm_);
     CallIC(code, expr->BinaryOperationFeedbackId());
     patch_site.EmitPatchInfo();
   }
   __ B(&done);
 
   __ Bind(&both_smis);
   // Smi case. This code works in the same way as the smi-smi case in the type
   // recording binary operation stub, see
@@ skipping 59 matching lines @@
       break;
     default:
       UNREACHABLE();
   }
 
   __ Bind(&done);
   context()->Plug(x0);
 }
 
 
-void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr,
-                                     Token::Value op,
-                                     OverwriteMode mode) {
+void FullCodeGenerator::EmitBinaryOp(BinaryOperation* expr, Token::Value op) {
   __ Pop(x1);
-  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.
   {
     Assembler::BlockPoolsScope scope(masm_);
     CallIC(code, expr->BinaryOperationFeedbackId());
     patch_site.EmitPatchInfo();
   }
   context()->Plug(x0);
 }
 
 
@@ skipping 2287 matching lines @@
 
   __ Bind(&stub_call);
   __ Mov(x1, x0);
   __ Mov(x0, Smi::FromInt(count_value));
 
   // Record position before stub call.
   SetSourcePosition(expr->position());
 
   {
     Assembler::BlockPoolsScope scope(masm_);
-    Handle<Code> code =
-        CodeFactory::BinaryOpIC(isolate(), Token::ADD, NO_OVERWRITE).code();
+    Handle<Code> code = CodeFactory::BinaryOpIC(isolate(), Token::ADD).code();
     CallIC(code, expr->CountBinOpFeedbackId());
     patch_site.EmitPatchInfo();
   }
   __ Bind(&done);
 
   // Store the value returned in x0.
   switch (assign_type) {
     case VARIABLE:
       if (expr->is_postfix()) {
         { EffectContext context(this);
@@ skipping 868 matching lines @@
   return previous_;
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM64