Less aggressive polling when concurrently compiling for OSR.

src/x64/builtins-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 1383 matching lines @@
   __ lea(rax, Operand(rax, rbx, times_1, Code::kHeaderSize - kHeapObjectTag));
 
   // Overwrite the return address on the stack.
   __ movq(Operand(rsp, 0), rax);
 
   // And "return" to the OSR entry point of the function.
   __ ret(0);
 }
 
 
+void Builtins::Generate_OsrAfterStackCheck(MacroAssembler* masm) {
+  // We check the stack limit as indicator that recompilation might be done.
+  Label ok;
+  __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
+  __ j(above_equal, &ok);
+  {
+    FrameScope scope(masm, StackFrame::INTERNAL);
+    __ CallRuntime(Runtime::kStackGuard, 0);
+  }
+  __ jmp(masm->isolate()->builtins()->OnStackReplacement(),
+         RelocInfo::CODE_TARGET);
+
+  __ bind(&ok);
+  __ ret(0);
+}
+
+
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64