Improve array to string conversion.

src/x64/full-codegen-x64.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 3029 matching lines @@
     __ jmp(&done);
   }
 
   __ bind(&not_date_object);
   __ CallRuntime(Runtime::kThrowNotDateError, 0);
   __ bind(&done);
   context()->Plug(rax);
 }
 
 
+void FullCodeGenerator::EmitOneByteSeqStringSetChar(CallRuntime* expr) {
+  ZoneList<Expression*>* args = expr->arguments();
+  ASSERT_EQ(3, args->length());
+
+  VisitForStackValue(args->at(1));  // index
+  VisitForStackValue(args->at(2));  // value
+  __ pop(rcx);
+  __ pop(rbx);
+  VisitForAccumulatorValue(args->at(0));  // string
+
+  SeqStringSetCharGenerator::Generate(masm_, true, rax, rbx, rcx);
+  context()->Plug(rax);
+}
+
+
+void FullCodeGenerator::EmitTwoByteSeqStringSetChar(CallRuntime* expr) {
+  ZoneList<Expression*>* args = expr->arguments();
+  ASSERT_EQ(3, args->length());
+
+  VisitForStackValue(args->at(1));  // index
+  VisitForStackValue(args->at(2));  // value
+  __ pop(rcx);
+  __ pop(rbx);
+  VisitForAccumulatorValue(args->at(0));  // string
+
+  SeqStringSetCharGenerator::Generate(masm_, false, rax, rbx, rcx);
+  context()->Plug(rax);
+}
+
+
 void FullCodeGenerator::EmitMathPow(CallRuntime* expr) {
   // Load the arguments on the stack and call the runtime function.
   ZoneList<Expression*>* args = expr->arguments();
   ASSERT(args->length() == 2);
   VisitForStackValue(args->at(0));
   VisitForStackValue(args->at(1));
   MathPowStub stub(MathPowStub::ON_STACK);
   __ CallStub(&stub);
   context()->Plug(rax);
 }
@@ skipping 1435 matching lines @@
   *context_length = 0;
   return previous_;
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64