/*
* Copyright (C) 2008 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
* 3. Neither the name of Apple Computer, Inc. ("Apple") nor the names of
* its contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef SamplingTool_h
#define SamplingTool_h
#include "Strong.h"
#include "Nodes.h"
#include "Opcode.h"
#include <wtf/Assertions.h>
#include <wtf/HashMap.h>
#include <wtf/Threading.h>
namespace JSC {
class ScriptExecutable;
class SamplingFlags {
friend class JIT;
public:
static void start();
static void stop();
#if ENABLE(SAMPLING_FLAGS)
static void setFlag(unsigned flag)
{
ASSERT(flag >= 1);
ASSERT(flag <= 32);
s_flags |= 1u << (flag - 1);
}
static void clearFlag(unsigned flag)
{
ASSERT(flag >= 1);
ASSERT(flag <= 32);
s_flags &= ~(1u << (flag - 1));
}
static void sample();
class ScopedFlag {
public:
ScopedFlag(int flag)
: m_flag(flag)
{
setFlag(flag);
}
~ScopedFlag()
{
clearFlag(m_flag);
}
private:
int m_flag;
};
#endif
private:
static uint32_t s_flags;
#if ENABLE(SAMPLING_FLAGS)
static uint64_t s_flagCounts[33];
#endif
};
class CodeBlock;
class ExecState;
class Interpreter;
class ScopeNode;
struct Instruction;
struct ScriptSampleRecord {
ScriptSampleRecord(JSGlobalData& globalData, ScriptExecutable* executable)
: m_executable(globalData, executable)
, m_codeBlock(0)
, m_sampleCount(0)
, m_opcodeSampleCount(0)
, m_samples(0)
, m_size(0)
{
}
~ScriptSampleRecord()
{
if (m_samples)
free(m_samples);
}
void sample(CodeBlock*, Instruction*);
Strong<ScriptExecutable> m_executable;
CodeBlock* m_codeBlock;
int m_sampleCount;
int m_opcodeSampleCount;
int* m_samples;
unsigned m_size;
};
typedef WTF::HashMap<ScriptExecutable*, ScriptSampleRecord*> ScriptSampleRecordMap;
class SamplingThread {
public:
// Sampling thread state.
static bool s_running;
static unsigned s_hertz;
static ThreadIdentifier s_samplingThread;
static void start(unsigned hertz=10000);
static void stop();
static void* threadStartFunc(void*);
};
class SamplingTool {
public:
friend struct CallRecord;
friend class HostCallRecord;
#if ENABLE(OPCODE_SAMPLING)
class CallRecord {
WTF_MAKE_NONCOPYABLE(CallRecord);
public:
CallRecord(SamplingTool* samplingTool)
: m_samplingTool(samplingTool)
, m_savedSample(samplingTool->m_sample)
, m_savedCodeBlock(samplingTool->m_codeBlock)
{
}
~CallRecord()
{
m_samplingTool->m_sample = m_savedSample;
m_samplingTool->m_codeBlock = m_savedCodeBlock;
}
private:
SamplingTool* m_samplingTool;
intptr_t m_savedSample;
CodeBlock* m_savedCodeBlock;
};
class HostCallRecord : public CallRecord {
public:
HostCallRecord(SamplingTool* samplingTool)
: CallRecord(samplingTool)
{
samplingTool->m_sample |= 0x1;
}
};
#else
class CallRecord {
WTF_MAKE_NONCOPYABLE(CallRecord);
public:
CallRecord(SamplingTool*)
{
}
};
class HostCallRecord : public CallRecord {
public:
HostCallRecord(SamplingTool* samplingTool)
: CallRecord(samplingTool)
{
}
};
#endif
SamplingTool(Interpreter* interpreter)
: m_interpreter(interpreter)
, m_codeBlock(0)
, m_sample(0)
, m_sampleCount(0)
, m_opcodeSampleCount(0)
#if ENABLE(CODEBLOCK_SAMPLING)
, m_scopeSampleMap(new ScriptSampleRecordMap())
#endif
{
memset(m_opcodeSamples, 0, sizeof(m_opcodeSamples));
memset(m_opcodeSamplesInCTIFunctions, 0, sizeof(m_opcodeSamplesInCTIFunctions));
}
~SamplingTool()
{
#if ENABLE(CODEBLOCK_SAMPLING)
deleteAllValues(*m_scopeSampleMap);
#endif
}
void setup();
void dump(ExecState*);
void notifyOfScope(ScriptExecutable* scope);
void sample(CodeBlock* codeBlock, Instruction* vPC)
{
ASSERT(!(reinterpret_cast<intptr_t>(vPC) & 0x3));
m_codeBlock = codeBlock;
m_sample = reinterpret_cast<intptr_t>(vPC);
}
CodeBlock** codeBlockSlot() { return &m_codeBlock; }
intptr_t* sampleSlot() { return &m_sample; }
void* encodeSample(Instruction* vPC, bool inCTIFunction = false, bool inHostFunction = false)
{
ASSERT(!(reinterpret_cast<intptr_t>(vPC) & 0x3));
return reinterpret_cast<void*>(reinterpret_cast<intptr_t>(vPC) | (static_cast<intptr_t>(inCTIFunction) << 1) | static_cast<intptr_t>(inHostFunction));
}
static void sample();
private:
class Sample {
public:
Sample(volatile intptr_t sample, CodeBlock* volatile codeBlock)
: m_sample(sample)
, m_codeBlock(codeBlock)
{
}
bool isNull() { return !m_sample; }
CodeBlock* codeBlock() { return m_codeBlock; }
Instruction* vPC() { return reinterpret_cast<Instruction*>(m_sample & ~0x3); }
bool inHostFunction() { return m_sample & 0x1; }
bool inCTIFunction() { return m_sample & 0x2; }
private:
intptr_t m_sample;
CodeBlock* m_codeBlock;
};
void doRun();
static SamplingTool* s_samplingTool;
Interpreter* m_interpreter;
// State tracked by the main thread, used by the sampling thread.
CodeBlock* m_codeBlock;
intptr_t m_sample;
// Gathered sample data.
long long m_sampleCount;
long long m_opcodeSampleCount;
unsigned m_opcodeSamples[numOpcodeIDs];
unsigned m_opcodeSamplesInCTIFunctions[numOpcodeIDs];
#if ENABLE(CODEBLOCK_SAMPLING)
Mutex m_scriptSampleMapMutex;
OwnPtr<ScriptSampleRecordMap> m_scopeSampleMap;
#endif
};
// AbstractSamplingCounter:
//
// Implements a named set of counters, printed on exit if ENABLE(SAMPLING_COUNTERS).
// See subclasses below, SamplingCounter, GlobalSamplingCounter and DeletableSamplingCounter.
class AbstractSamplingCounter {
friend class DeletableSamplingCounter;
public:
void count(uint32_t count = 1)
{
m_counter += count;
}
static void dump();
int64_t* addressOfCounter() { return &m_counter; }
protected:
// Effectively the contructor, however called lazily in the case of GlobalSamplingCounter.
void init(const char* name)
{
m_counter = 0;
m_name = name;
// Set m_next to point to the head of the chain, and inform whatever is
// currently at the head that this node will now hold the pointer to it.
m_next = s_abstractSamplingCounterChain;
s_abstractSamplingCounterChain->m_referer = &m_next;
// Add this node to the head of the list.
s_abstractSamplingCounterChain = this;
m_referer = &s_abstractSamplingCounterChain;
}
int64_t m_counter;
const char* m_name;
AbstractSamplingCounter* m_next;
// This is a pointer to the pointer to this node in the chain; used to
// allow fast linked list deletion.
AbstractSamplingCounter** m_referer;
// Null object used to detect end of static chain.
static AbstractSamplingCounter s_abstractSamplingCounterChainEnd;
static AbstractSamplingCounter* s_abstractSamplingCounterChain;
static bool s_completed;
};
#if ENABLE(SAMPLING_COUNTERS)
// SamplingCounter:
//
// This class is suitable and (hopefully!) convenient for cases where a counter is
// required within the scope of a single function. It can be instantiated as a
// static variable since it contains a constructor but not a destructor (static
// variables in WebKit cannot have destructors).
//
// For example:
//
// void someFunction()
// {
// static SamplingCounter countMe("This is my counter. There are many like it, but this one is mine.");
// countMe.count();
// // ...
// }
//
class SamplingCounter : public AbstractSamplingCounter {
public:
SamplingCounter(const char* name) { init(name); }
};
// GlobalSamplingCounter:
//
// This class is suitable for use where a counter is to be declared globally,
// since it contains neither a constructor nor destructor. Instead, ensure
// that 'name()' is called to provide the counter with a name (and also to
// allow it to be printed out on exit).
//
// GlobalSamplingCounter globalCounter;
//
// void firstFunction()
// {
// // Put this within a function that is definitely called!
// // (Or alternatively alongside all calls to 'count()').
// globalCounter.name("I Name You Destroyer.");
// globalCounter.count();
// // ...
// }
//
// void secondFunction()
// {
// globalCounter.count();
// // ...
// }
//
class GlobalSamplingCounter : public AbstractSamplingCounter {
public:
void name(const char* name)
{
// Global objects should be mapped in zero filled memory, so this should
// be a safe (albeit not necessarily threadsafe) check for 'first call'.
if (!m_next)
init(name);
}
};
// DeletableSamplingCounter:
//
// The above classes (SamplingCounter, GlobalSamplingCounter), are intended for
// use within a global or static scope, and as such cannot have a destructor.
// This means there is no convenient way for them to remove themselves from the
// static list of counters, and should an instance of either class be freed
// before 'dump()' has walked over the list it will potentially walk over an
// invalid pointer.
//
// This class is intended for use where the counter may possibly be deleted before
// the program exits. Should this occur, the counter will print it's value to
// stderr, and remove itself from the static list. Example:
//
// DeletableSamplingCounter* counter = new DeletableSamplingCounter("The Counter With No Name");
// counter->count();
// delete counter;
//
class DeletableSamplingCounter : public AbstractSamplingCounter {
public:
DeletableSamplingCounter(const char* name) { init(name); }
~DeletableSamplingCounter()
{
if (!s_completed)
fprintf(stderr, "DeletableSamplingCounter \"%s\" deleted early (with count %lld)\n", m_name, m_counter);
// Our m_referer pointer should know where the pointer to this node is,
// and m_next should know that this node is the previous node in the list.
ASSERT(*m_referer == this);
ASSERT(m_next->m_referer == &m_next);
// Remove this node from the list, and inform m_next that we have done so.
m_next->m_referer = m_referer;
*m_referer = m_next;
}
};
#endif
} // namespace JSC
#endif // SamplingTool_h