MIPS: Remove the obsolete OverwriteMode optimization.

src/mips64/full-codegen-mips64.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_MIPS64
 
 // Note on Mips implementation:
 //
@@ skipping 2008 matching lines @@
           EmitKeyedPropertyLoad(property);
           PrepareForBailoutForId(property->LoadId(), TOS_REG);
           break;
       }
     }
 
     Token::Value op = expr->binary_op();
     __ push(v0);  // 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 362 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, smi_case, stub_call;
 
   Register scratch1 = a2;
   Register scratch2 = a3;
 
   // Get the arguments.
   Register left = a1;
   Register right = a0;
   __ pop(left);
   __ mov(a0, result_register());
 
   // Perform combined smi check on both operands.
   __ Or(scratch1, left, Operand(right));
   STATIC_ASSERT(kSmiTag == 0);
   JumpPatchSite patch_site(masm_);
   patch_site.EmitJumpIfSmi(scratch1, &smi_case);
 
   __ bind(&stub_call);
-  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);
 
   __ bind(&smi_case);
   // Smi case. This code works the same way as the smi-smi case in the type
   // recording binary operation stub, see
   switch (op) {
     case Token::SAR:
       __ GetLeastBitsFromSmi(scratch1, right, 5);
@@ skipping 108 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) {
   __ mov(a0, result_register());
   __ pop(a1);
-  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(v0);
 }
 
 
 void FullCodeGenerator::EmitAssignment(Expression* expr) {
   DCHECK(expr->IsValidReferenceExpression());
 
@@ skipping 2253 matching lines @@
     }
   }
 
   __ bind(&stub_call);
   __ mov(a1, v0);
   __ li(a0, Operand(Smi::FromInt(count_value)));
 
   // Record position before stub call.
   SetSourcePosition(expr->position());
 
-  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 v0.
   switch (assign_type) {
     case VARIABLE:
       if (expr->is_postfix()) {
         { EffectContext context(this);
           EmitVariableAssignment(expr->expression()->AsVariableProxy()->var(),
@@ skipping 511 matching lines @@
       Assembler::target_address_at(pc_immediate_load_address)) ==
          reinterpret_cast<uint64_t>(
              isolate->builtins()->OsrAfterStackCheck()->entry()));
   return OSR_AFTER_STACK_CHECK;
 }
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_MIPS64