Count-based profiling for primitive functions (hidden behind a flag)

src/x64/full-codegen-x64.cc

Index: src/x64/full-codegen-x64.cc
diff --git a/src/x64/full-codegen-x64.cc b/src/x64/full-codegen-x64.cc
index 466c3f7238dec7e4a6cfde43700a2c699e16452b..def8aa15f5d55650923b85391b885d858f5d963b 100644
--- a/src/x64/full-codegen-x64.cc
+++ b/src/x64/full-codegen-x64.cc
@@ -1,4 +1,4 @@
-// Copyright 2011 the V8 project authors. All rights reserved.
+// 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:
@@ -129,6 +129,27 @@ void FullCodeGenerator::Generate(CompilationInfo* info) {
   }
 #endif
 
+  // We can optionally optimize based on counters rather than statistical
+  // sampling.
+  if (info->ShouldSelfOptimize()) {
+    if (FLAG_trace_opt) {
+      PrintF("[adding self-optimization header to %s]\n",
+             *info->function()->debug_name()->ToCString());
+    }
+    MaybeObject* maybe_cell = isolate()->heap()->AllocateJSGlobalPropertyCell(
+        Smi::FromInt(Compiler::kCallsUntilPrimitiveOpt));
+    JSGlobalPropertyCell* cell;
+    if (maybe_cell->To(&cell)) {
+      __ movq(rax, Handle<JSGlobalPropertyCell>(cell),
+              RelocInfo::EMBEDDED_OBJECT);
+      __ SmiAddConstant(FieldOperand(rax, JSGlobalPropertyCell::kValueOffset),
+                        Smi::FromInt(-1));
+      Handle<Code> compile_stub(
+          isolate()->builtins()->builtin(Builtins::kLazyRecompile));
+      __ j(zero, compile_stub, RelocInfo::CODE_TARGET);
+    }
+  }
+
   // Strict mode functions and builtins need to replace the receiver
   // with undefined when called as functions (without an explicit
   // receiver object). rcx is zero for method calls and non-zero for