Support profiler stack sampling in any situation.

src/log.cc

 // Copyright 2006-2008 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 124 matching lines @@
 
 //
 // StackTracer implementation
 //
 void StackTracer::Trace(TickSample* sample) {
   if (sample->state == GC) {
     sample->frames_count = 0;
     return;
   }
 
-  // If c_entry_fp is available, this means that we are inside a C++
-  // function and sample->fp value isn't reliable due to FPO.
-  if (Top::c_entry_fp(Top::GetCurrentThread()) != NULL) {
-    SafeStackTraceFrameIterator it(
-        reinterpret_cast<Address>(sample->sp),
-        reinterpret_cast<Address>(low_stack_bound_));
-    int i = 0;
-    while (!it.done() && i < TickSample::kMaxFramesCount) {
-      sample->stack[i++] = it.frame()->pc();
-      it.Advance();
-    }
-    sample->frames_count = i;
-  } else if (sample->sp < sample->fp && sample->fp < low_stack_bound_) {
-    // The check assumes that stack grows from lower addresses.
-    sample->stack[0] = Memory::Address_at(
-        (Address)(sample->fp + StandardFrameConstants::kCallerPCOffset));
-    sample->frames_count = 1;
-  } else {
-    // FP seems to be in some intermediate state,
-    // better discard this sample
-    sample->frames_count = 0;
+  SafeStackTraceFrameIterator it(
+      reinterpret_cast<Address>(sample->fp),
+      reinterpret_cast<Address>(sample->sp),
+      reinterpret_cast<Address>(sample->sp),
+      reinterpret_cast<Address>(low_stack_bound_));
+  int i = 0;
+  while (!it.done() && i < TickSample::kMaxFramesCount) {
+    sample->stack[i++] = it.frame()->pc();
+    it.Advance();
   }
+  sample->frames_count = i;
 }
 
 
 //
 // Ticker used to provide ticks to the profiler and the sliding state
 // window.
 //
 class Ticker: public Sampler {
  public:
   explicit Ticker(int interval, unsigned int low_stack_bound):
@@ skipping 752 matching lines @@
 #ifdef ENABLE_LOGGING_AND_PROFILING
 void Logger::TickEvent(TickSample* sample, bool overflow) {
   if (logfile_ == NULL || !FLAG_prof) return;
   LogMessageBuilder msg;
   msg.Append("tick,0x%x,0x%x,%d", sample->pc, sample->sp,
              static_cast<int>(sample->state));
   if (overflow) {
     msg.Append(",overflow");
   }
   for (int i = 0; i < sample->frames_count; ++i) {
-    msg.Append(",%p", sample->stack[i]);
+    msg.Append(",0x%x", reinterpret_cast<uint32_t>(sample->stack[i]));
   }
   msg.Append('\n');
   msg.WriteToLogFile();
 }
 
 
 bool Logger::IsProfilerPaused() {
   return profiler_->paused();
 }
 
@@ skipping 189 matching lines @@
   if (FLAG_log_state_changes) {
     LOG(UncheckedStringEvent("Leaving", StateToString(state_)));
     if (previous_) {
       LOG(UncheckedStringEvent("To", StateToString(previous_->state_)));
     }
   }
 }
 #endif
 
 } }  // namespace v8::internal