Small change to stack checks in unoptimized code.

src/x64/full-codegen-x64.cc

-// Copyright 2010 the V8 project authors. All rights reserved.
+// Copyright 2011 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
 //       with the distribution.
@@ skipping 191 matching lines @@
 }
 
 
 void FullCodeGenerator::EmitStackCheck(IterationStatement* stmt) {
   Comment cmnt(masm_, "[ Stack check");
   NearLabel ok;
   __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
   __ j(above_equal, &ok);
   StackCheckStub stub;
   __ CallStub(&stub);
+  // Record a mapping of this PC offset to the OSR id.  This is used to find
+  // the AST id from the unoptimized code in order to use it as a key into
+  // the deoptimization input data found in the optimized code.
+  RecordStackCheck(stmt->OsrEntryId());
+
   __ bind(&ok);
   PrepareForBailoutForId(stmt->EntryId(), NO_REGISTERS);
+  // Record a mapping of the OSR id to this PC.  This is used if the OSR
+  // entry becomes the target of a bailout.  We don't expect it to be, but
+  // we want it to work if it is.
   PrepareForBailoutForId(stmt->OsrEntryId(), NO_REGISTERS);
-  RecordStackCheck(stmt->OsrEntryId());
 }
 
 
 void FullCodeGenerator::EmitReturnSequence() {
   Comment cmnt(masm_, "[ Return sequence");
   if (return_label_.is_bound()) {
     __ jmp(&return_label_);
   } else {
     __ bind(&return_label_);
     if (FLAG_trace) {
@@ skipping 3294 matching lines @@
   __ ret(0);
 }
 
 
 #undef __
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64