Fix usage of heap_

runtime/vm/profiler.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "platform/utils.h"
 
 #include "vm/allocation.h"
 #include "vm/atomic.h"
 #include "vm/code_patcher.h"
 #include "vm/isolate.h"
@@ skipping 856 matching lines @@
 // Notes on stack frame walking:
 //
 // The sampling profiler will collect up to Sample::kNumStackFrames stack frames
 // The stack frame walking code uses the frame pointer to traverse the stack.
 // If the VM is compiled without frame pointers (which is the default on
 // recent GCC versions with optimizing enabled) the stack walking code may
 // fail (sometimes leading to a crash).
 //
 class ProfilerSampleStackWalker : public ValueObject {
  public:
-  ProfilerSampleStackWalker(Heap* heap,
-                            Sample* sample,
+  ProfilerSampleStackWalker(Sample* sample,
                             uword stack_lower,
                             uword stack_upper,
                             uword pc,
                             uword fp,
                             uword sp)
-      : heap_(heap),
-        sample_(sample),
+      : sample_(sample),
         stack_upper_(stack_upper),
         original_pc_(pc),
         original_fp_(fp),
         original_sp_(sp),
         lower_bound_(stack_lower) {
     ASSERT(sample_ != NULL);
   }
 
+#if defined(DEBUG_STACK_WALK)

[siva, 2014/02/27 18:30:48]

I missed this in the last round, normally we don't do #defines like
this, I thought it was under #if defined(DEBUG) didn't realize
it was a different symbol.

Another question why does heap have to be an instance variable of
ProfilerSampleStackWalker why not just set a local variable
in walk and pass it down as an argument to VerifyCodeAddress.

+  void set_heap(Heap* heap) {
+    heap_ = heap;
+  }
+#endif
+
   int walk() {
     const intptr_t kMaxStep = 0x1000;  // 4K.
     const bool kWalkStack = true;  // Walk the stack.
     // Always store the exclusive PC.
     sample_->SetAt(0, original_pc_);
     if (!kWalkStack) {
       // Not walking the stack, only took exclusive sample.
       return 1;
     }
     uword* pc = reinterpret_cast<uword*>(original_pc_);
@@ skipping 69 matching lines @@
   bool ValidFramePointer(uword* fp) const {
     if (fp == NULL) {
       return false;
     }
     uword cursor = reinterpret_cast<uword>(fp);
     cursor += sizeof(fp);
     bool r = cursor >= lower_bound_ && cursor < stack_upper_;
     return r;
   }
 
+#if defined(DEBUG_STACK_WALK)
   Heap* heap_;
+#endif
   Sample* sample_;
   const uword stack_upper_;
   const uword original_pc_;
   const uword original_fp_;
   const uword original_sp_;
   uword lower_bound_;
 };
 
 void Profiler::RecordSampleInterruptCallback(
     const InterruptedThreadState& state,
@@ skipping 12 matching lines @@
   }
   Sample* sample = sample_buffer->ReserveSample();
   sample->Init(isolate, OS::GetCurrentTimeMicros(), state.tid);
   uword stack_lower = 0;
   uword stack_upper = 0;
   isolate->GetStackBounds(&stack_lower, &stack_upper);
   if ((stack_lower == 0) || (stack_upper == 0)) {
     stack_lower = 0;
     stack_upper = 0;
   }
-  ProfilerSampleStackWalker stackWalker(isolate->heap(), sample, stack_lower,
-                                        stack_upper, state.pc, state.fp,
-                                        state.sp);
+  ProfilerSampleStackWalker stackWalker(sample, stack_lower, stack_upper,
+                                        state.pc, state.fp, state.sp);
+#if defined(DEBUG_STACK_WALK)
+  stackWalker.set_heap(isolate->heap());
+#endif
   stackWalker.walk();
 }
 
 
 }  // namespace dart