Optimize functions on a second thread.

src/x64/builtins-x64.cc

Index: src/x64/builtins-x64.cc
diff --git a/src/x64/builtins-x64.cc b/src/x64/builtins-x64.cc
index 0af0a434772602fbdb104c77f18e24e2d1813357..b19a3d0878a1205fae901f15d40badc07d9f0a31 100644
--- a/src/x64/builtins-x64.cc
+++ b/src/x64/builtins-x64.cc
@@ -73,6 +73,45 @@ void Builtins::Generate_Adaptor(MacroAssembler* masm,
 }
 
 
+static void GenerateTailCallToSharedCode(MacroAssembler* masm) {
+  __ movq(kScratchRegister,
+          FieldOperand(rdi, JSFunction::kSharedFunctionInfoOffset));
+  __ movq(kScratchRegister,
+          FieldOperand(kScratchRegister, SharedFunctionInfo::kCodeOffset));
+  __ lea(kScratchRegister, FieldOperand(kScratchRegister, Code::kHeaderSize));
+  __ jmp(kScratchRegister);
+}
+
+
+void Builtins::Generate_InRecompileQueue(MacroAssembler* masm) {
+  GenerateTailCallToSharedCode(masm);
+}
+
+
+void Builtins::Generate_ParallelRecompile(MacroAssembler* masm) {
+  {
+    FrameScope scope(masm, StackFrame::INTERNAL);
+
+    // Push a copy of the function onto the stack.
+    __ push(rdi);
+    // Push call kind information.
+    __ push(rcx);
+
+    __ push(rdi);  // Function is also the parameter to the runtime call.
+    __ CallRuntime(Runtime::kParallelRecompile, 1);
+
+    // Restore call kind information.
+    __ pop(rcx);
+    // Restore receiver.
+    __ pop(rdi);
+
+    // Tear down internal frame.
+  }
+
+  GenerateTailCallToSharedCode(masm);
+}
+
+
 static void Generate_JSConstructStubHelper(MacroAssembler* masm,
                                            bool is_api_function,
                                            bool count_constructions) {