X64: enable stack sampling in profiler.

src/x64/codegen-x64.cc

Index: src/x64/codegen-x64.cc
diff --git a/src/x64/codegen-x64.cc b/src/x64/codegen-x64.cc
index 3112ecc1262a034db63729e72031397ec1871ef8..4c2ae7a65e19827324541cb5abcaccfb070cea5b 100644
--- a/src/x64/codegen-x64.cc
+++ b/src/x64/codegen-x64.cc
@@ -3421,6 +3421,16 @@ void CodeGenerator::GenerateObjectEquals(ZoneList<Expression*>* args) {
 }
 
 
+void CodeGenerator::GenerateGetFramePointer(ZoneList<Expression*>* args) {
+  ASSERT(args->length() == 0);
+  ASSERT(kSmiTag == 0);  // RBP value is aligned, so it should look like Smi.
+  Result rbp_as_smi = allocator_->Allocate();
+  ASSERT(rbp_as_smi.is_valid());
+  __ movq(rbp_as_smi.reg(), rbp);
+  frame_->Push(&rbp_as_smi);
+}
+
+
 void CodeGenerator::GenerateRandomPositiveSmi(ZoneList<Expression*>* args) {
   ASSERT(args->length() == 0);
   frame_->SpillAll();
@@ -6570,6 +6580,9 @@ void CEntryStub::GenerateBody(MacroAssembler* masm, bool is_debug_break) {
 
 void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
   Label invoke, exit;
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  Label not_outermost_js, not_outermost_js_2;
+#endif
 
   // Setup frame.
   __ push(rbp);
@@ -6595,6 +6608,17 @@ void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
   __ load_rax(c_entry_fp);
   __ push(rax);
 
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  // If this is the outermost JS call, set js_entry_sp value.
+  ExternalReference js_entry_sp(Top::k_js_entry_sp_address);
+  __ load_rax(js_entry_sp);
+  __ testq(rax, rax);
+  __ j(NegateCondition(zero), &not_outermost_js);

[William Hesse, 2009/07/31 10:00:12]

What is the difference between not_zero and NegateCondition(zero)?

[Mikhail Naganov, 2009/07/31 11:06:05]

Thanks. I rarely touch code generation, so I'm not aware of all shortcuts it
has. Fixed.

+  __ movq(rax, rbp);
+  __ store_rax(js_entry_sp);
+  __ bind(&not_outermost_js);
+#endif
+
   // Call a faked try-block that does the invoke.
   __ call(&invoke);
 
@@ -6637,6 +6661,16 @@ void JSEntryStub::GenerateBody(MacroAssembler* masm, bool is_construct) {
   // Pop next_sp.
   __ addq(rsp, Immediate(StackHandlerConstants::kSize - kPointerSize));
 
+#ifdef ENABLE_LOGGING_AND_PROFILING
+  // If current EBP value is the same as js_entry_sp value, it means that
+  // the current function is the outermost.
+  __ movq(kScratchRegister, js_entry_sp);
+  __ cmpq(rbp, Operand(kScratchRegister, 0));
+  __ j(NegateCondition(equal), &not_outermost_js_2);
+  __ movq(Operand(kScratchRegister, 0), Immediate(0));
+  __ bind(&not_outermost_js_2);
+#endif
+
   // Restore the top frame descriptor from the stack.
   __ bind(&exit);
   __ movq(kScratchRegister, ExternalReference(Top::k_c_entry_fp_address));