gecko/js/public/ProfilingFrameIterator.h

144 lines
4.2 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* vim: set ts=8 sts=4 et sw=4 tw=99:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef js_ProfilingFrameIterator_h
#define js_ProfilingFrameIterator_h
#include "mozilla/Alignment.h"
#include <stdint.h>
#include "js/Utility.h"
class JSAtom;
struct JSRuntime;
namespace js {
class Activation;
class AsmJSProfilingFrameIterator;
namespace jit {
class JitActivation;
class JitProfilingFrameIterator;
}
}
namespace JS {
// This iterator can be used to walk the stack of a thread suspended at an
// arbitrary pc. To provide acurate results, profiling must have been enabled
// (via EnableRuntimeProfilingStack) before executing the callstack being
// unwound.
class JS_PUBLIC_API(ProfilingFrameIterator)
{
JSRuntime *rt_;
uint32_t sampleBufferGen_;
js::Activation *activation_;
// When moving past a JitActivation, we need to save the prevJitTop
// from it to use as the exit-frame pointer when the next caller jit
// activation (if any) comes around.
void *savedPrevJitTop_;
static const unsigned StorageSpace = 6 * sizeof(void*);
mozilla::AlignedStorage<StorageSpace> storage_;
js::AsmJSProfilingFrameIterator &asmJSIter() {
MOZ_ASSERT(!done());
MOZ_ASSERT(isAsmJS());
return *reinterpret_cast<js::AsmJSProfilingFrameIterator*>(storage_.addr());
}
const js::AsmJSProfilingFrameIterator &asmJSIter() const {
MOZ_ASSERT(!done());
MOZ_ASSERT(isAsmJS());
return *reinterpret_cast<const js::AsmJSProfilingFrameIterator*>(storage_.addr());
}
js::jit::JitProfilingFrameIterator &jitIter() {
MOZ_ASSERT(!done());
MOZ_ASSERT(isJit());
return *reinterpret_cast<js::jit::JitProfilingFrameIterator*>(storage_.addr());
}
const js::jit::JitProfilingFrameIterator &jitIter() const {
MOZ_ASSERT(!done());
MOZ_ASSERT(isJit());
return *reinterpret_cast<const js::jit::JitProfilingFrameIterator*>(storage_.addr());
}
void settle();
bool hasSampleBufferGen() const {
return sampleBufferGen_ != UINT32_MAX;
}
public:
struct RegisterState
{
RegisterState() : pc(nullptr), sp(nullptr), lr(nullptr) {}
void *pc;
void *sp;
void *lr;
};
ProfilingFrameIterator(JSRuntime *rt, const RegisterState &state,
uint32_t sampleBufferGen = UINT32_MAX);
~ProfilingFrameIterator();
void operator++();
bool done() const { return !activation_; }
// Assuming the stack grows down (we do), the return value:
// - always points into the stack
// - is weakly monotonically increasing (may be equal for successive frames)
// - will compare greater than newer native and psuedo-stack frame addresses
// and less than older native and psuedo-stack frame addresses
void *stackAddress() const;
enum FrameKind
{
Frame_Baseline,
Frame_Ion,
Frame_AsmJS
};
struct Frame
{
FrameKind kind;
void *stackAddress;
void *returnAddress;
void *activation;
const char *label;
bool hasTrackedOptimizations;
};
uint32_t extractStack(Frame *frames, uint32_t offset, uint32_t end) const;
private:
void iteratorConstruct(const RegisterState &state);
void iteratorConstruct();
void iteratorDestroy();
bool iteratorDone();
bool isAsmJS() const;
bool isJit() const;
};
JS_FRIEND_API(bool)
IsProfilingEnabledForRuntime(JSRuntime *runtime);
/**
* After each sample run, this method should be called with the latest sample
* buffer generation, and the lapCount. It will update corresponding fields on
* JSRuntime.
*
* See fields |profilerSampleBufferGen|, |profilerSampleBufferLapCount| on
* JSRuntime for documentation about what these values are used for.
*/
JS_FRIEND_API(void)
UpdateJSRuntimeProfilerSampleBufferGen(JSRuntime *runtime, uint32_t generation,
uint32_t lapCount);
} // namespace JS
#endif /* js_ProfilingFrameIterator_h */