src/third_party/WebKit/Source/JavaScriptCore/bytecode/SamplingTool.cpp - cobalt - Git at Google

 /*
  * Copyright (C) 2008, 2009 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.
  */

 #include "config.h"
 #include "SamplingTool.h"

 #include "CodeBlock.h"
 #include "Interpreter.h"
 #include "Opcode.h"

 #if !OS(WINDOWS)
 #include <unistd.h>
 #endif

 namespace JSC {

 #if ENABLE(SAMPLING_FLAGS)

 void SamplingFlags::sample()
 {
     uint32_t mask = static_cast<uint32_t>(1 << 31);
     unsigned index;

     for (index = 0; index < 32; ++index) {
         if (mask & s_flags)
             break;
         mask >>= 1;
     }

     s_flagCounts[32 - index]++;
 }

 void SamplingFlags::start()
 {
     for (unsigned i = 0; i <= 32; ++i)
         s_flagCounts[i] = 0;
 }
 void SamplingFlags::stop()
 {
     uint64_t total = 0;
     for (unsigned i = 0; i <= 32; ++i)
         total += s_flagCounts[i];

     if (total) {
         dataLogF("\nSamplingFlags: sample counts with flags set: (%lld total)\n", total);
         for (unsigned i = 0; i <= 32; ++i) {
             if (s_flagCounts[i])
                 dataLogF("  [ %02d ] : %lld\t\t(%03.2f%%)\n", i, s_flagCounts[i], (100.0 * s_flagCounts[i]) / total);
         }
         dataLogF("\n");
     } else
     dataLogF("\nSamplingFlags: no samples.\n\n");
 }
 uint64_t SamplingFlags::s_flagCounts[33];

 #else
 void SamplingFlags::start() {}
 void SamplingFlags::stop() {}
 #endif

 #if ENABLE(SAMPLING_REGIONS)
 volatile uintptr_t SamplingRegion::s_currentOrReserved;
 Spectrum<const char*>* SamplingRegion::s_spectrum;
 unsigned long SamplingRegion::s_noneOfTheAbove;
 unsigned SamplingRegion::s_numberOfSamplesSinceDump;

 SamplingRegion::Locker::Locker()
 {
     uintptr_t previous;
     while (true) {
         previous = s_currentOrReserved;
         if (previous & 1) {
 #if OS(UNIX)
             sched_yield();
 #endif
             continue;
         }
         if (WTF::weakCompareAndSwapUIntPtr(&s_currentOrReserved, previous, previous | 1))
             break;
     }
 }

 SamplingRegion::Locker::~Locker()
 {
     // We don't need the CAS, but we do it out of an
     // abundance of caution (and because it gives us a memory fence, which is
     // never bad).
     uintptr_t previous;
     do {
         previous = s_currentOrReserved;
     } while (!WTF::weakCompareAndSwapUIntPtr(&s_currentOrReserved, previous, previous & ~1));
 }

 void SamplingRegion::sample()
 {
     // Make sure we lock s_current.
     Locker locker;

     // Create a spectrum if we don't have one already.
     if (!s_spectrum)
         s_spectrum = new Spectrum<const char*>();

     ASSERT(s_currentOrReserved & 1);

     // Walk the region stack, and record each region we see.
     SamplingRegion* region = bitwise_cast<SamplingRegion*>(s_currentOrReserved & ~1);
     if (region) {
         for (; region; region = region->m_previous)
             s_spectrum->add(region->m_name);
     } else
         s_noneOfTheAbove++;

     if (s_numberOfSamplesSinceDump++ == SamplingThread::s_hertz) {
         s_numberOfSamplesSinceDump = 0;
         dumpInternal();
     }
 }

 void SamplingRegion::dump()
 {
     Locker locker;

     dumpInternal();
 }

 void SamplingRegion::dumpInternal()
 {
     if (!s_spectrum) {
         dataLogF("\nSamplingRegion: was never sampled.\n\n");
         return;
     }

     Vector<Spectrum<const char*>::KeyAndCount> list = s_spectrum->buildList();

     unsigned long total = s_noneOfTheAbove;
     for (unsigned i = list.size(); i--;)
         total += list[i].count;

     dataLogF("\nSamplingRegion: sample counts for regions: (%lu samples)\n", total);

     for (unsigned i = list.size(); i--;)
         dataLogF("    %3.2lf%%  %s\n", (100.0 * list[i].count) / total, list[i].key);
 }
 #else // ENABLE(SAMPLING_REGIONS)
 void SamplingRegion::dump() { }
 #endif // ENABLE(SAMPLING_REGIONS)

 /*
   Start with flag 16 set.
   By doing this the monitoring of lower valued flags will be masked out
   until flag 16 is explictly cleared.
 */
 uint32_t SamplingFlags::s_flags = 1 << 15;


 #if OS(WINDOWS)

 static void sleepForMicroseconds(unsigned us)
 {
     unsigned ms = us / 1000;
     if (us && !ms)
         ms = 1;
     Sleep(ms);
 }

 #else

 static void sleepForMicroseconds(unsigned us)
 {
     usleep(us);
 }

 #endif

 static inline unsigned hertz2us(unsigned hertz)
 {
     return 1000000 / hertz;
 }


 SamplingTool* SamplingTool::s_samplingTool = 0;


 bool SamplingThread::s_running = false;
 unsigned SamplingThread::s_hertz = 10000;
 ThreadIdentifier SamplingThread::s_samplingThread;

 void SamplingThread::threadStartFunc(void*)
 {
     while (s_running) {
         sleepForMicroseconds(hertz2us(s_hertz));

 #if ENABLE(SAMPLING_FLAGS)
         SamplingFlags::sample();
 #endif
 #if ENABLE(SAMPLING_REGIONS)
         SamplingRegion::sample();
 #endif
 #if ENABLE(OPCODE_SAMPLING)
         SamplingTool::sample();
 #endif
     }
 }


 void SamplingThread::start(unsigned hertz)
 {
     ASSERT(!s_running);
     s_running = true;
     s_hertz = hertz;

     s_samplingThread = createThread(threadStartFunc, 0, "JavaScriptCore::Sampler");
 }

 void SamplingThread::stop()
 {
     ASSERT(s_running);
     s_running = false;
     waitForThreadCompletion(s_samplingThread);
 }


 void ScriptSampleRecord::sample(CodeBlock* codeBlock, Instruction* vPC)
 {
     if (!m_samples) {
         m_size = codeBlock->instructions().size();
         m_samples = static_cast<int*>(calloc(m_size, sizeof(int)));
         m_codeBlock = codeBlock;
     }

     ++m_sampleCount;

     unsigned offest = vPC - codeBlock->instructions().begin();
     // Since we don't read and write codeBlock and vPC atomically, this check
     // can fail if we sample mid op_call / op_ret.
     if (offest < m_size) {
         m_samples[offest]++;
         m_opcodeSampleCount++;
     }
 }

 void SamplingTool::doRun()
 {
     Sample sample(m_sample, m_codeBlock);
     ++m_sampleCount;

     if (sample.isNull())
         return;

     if (!sample.inHostFunction()) {
         unsigned opcodeID = m_interpreter->getOpcodeID(sample.vPC()[0].u.opcode);

         ++m_opcodeSampleCount;
         ++m_opcodeSamples[opcodeID];

         if (sample.inCTIFunction())
             m_opcodeSamplesInCTIFunctions[opcodeID]++;
     }

 #if ENABLE(CODEBLOCK_SAMPLING)
     if (CodeBlock* codeBlock = sample.codeBlock()) {
         MutexLocker locker(m_scriptSampleMapMutex);
         ScriptSampleRecord* record = m_scopeSampleMap->get(codeBlock->ownerExecutable());
         ASSERT(record);
         record->sample(codeBlock, sample.vPC());
     }
 #endif
 }

 void SamplingTool::sample()
 {
     s_samplingTool->doRun();
 }

 void SamplingTool::notifyOfScope(JSGlobalData& globalData, ScriptExecutable* script)
 {
 #if ENABLE(CODEBLOCK_SAMPLING)
     MutexLocker locker(m_scriptSampleMapMutex);
     m_scopeSampleMap->set(script, adoptPtr(new ScriptSampleRecord(globalData, script)));
 #else
     UNUSED_PARAM(globalData);
     UNUSED_PARAM(script);
 #endif
 }

 void SamplingTool::setup()
 {
     s_samplingTool = this;
 }

 #if ENABLE(OPCODE_SAMPLING)

 struct OpcodeSampleInfo {
     OpcodeID opcode;
     long long count;
     long long countInCTIFunctions;
 };

 struct LineCountInfo {
     unsigned line;
     unsigned count;
 };

 static int compareOpcodeIndicesSampling(const void* left, const void* right)
 {
     const OpcodeSampleInfo* leftSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(left);
     const OpcodeSampleInfo* rightSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(right);

     return (leftSampleInfo->count < rightSampleInfo->count) ? 1 : (leftSampleInfo->count > rightSampleInfo->count) ? -1 : 0;
 }

 #if ENABLE(CODEBLOCK_SAMPLING)
 static int compareLineCountInfoSampling(const void* left, const void* right)
 {
     const LineCountInfo* leftLineCount = reinterpret_cast<const LineCountInfo*>(left);
     const LineCountInfo* rightLineCount = reinterpret_cast<const LineCountInfo*>(right);

     return (leftLineCount->line > rightLineCount->line) ? 1 : (leftLineCount->line < rightLineCount->line) ? -1 : 0;
 }

 static int compareScriptSampleRecords(const void* left, const void* right)
 {
     const ScriptSampleRecord* const leftValue = *static_cast<const ScriptSampleRecord* const *>(left);
     const ScriptSampleRecord* const rightValue = *static_cast<const ScriptSampleRecord* const *>(right);

     return (leftValue->m_sampleCount < rightValue->m_sampleCount) ? 1 : (leftValue->m_sampleCount > rightValue->m_sampleCount) ? -1 : 0;
 }
 #endif

 void SamplingTool::dump(ExecState* exec)
 {
     // Tidies up SunSpider output by removing short scripts - such a small number of samples would likely not be useful anyhow.
     if (m_sampleCount < 10)
         return;

     // (1) Build and sort 'opcodeSampleInfo' array.

     OpcodeSampleInfo opcodeSampleInfo[numOpcodeIDs];
     for (int i = 0; i < numOpcodeIDs; ++i) {
         opcodeSampleInfo[i].opcode = static_cast<OpcodeID>(i);
         opcodeSampleInfo[i].count = m_opcodeSamples[i];
         opcodeSampleInfo[i].countInCTIFunctions = m_opcodeSamplesInCTIFunctions[i];
     }

     qsort(opcodeSampleInfo, numOpcodeIDs, sizeof(OpcodeSampleInfo), compareOpcodeIndicesSampling);

     // (2) Print Opcode sampling results.

     dataLogF("\nBytecode samples [*]\n");
     dataLogF("                             sample   %% of       %% of     |   cti     cti %%\n");
     dataLogF("opcode                       count     VM        total    |  count   of self\n");
     dataLogF("-------------------------------------------------------   |  ----------------\n");

     for (int i = 0; i < numOpcodeIDs; ++i) {
         long long count = opcodeSampleInfo[i].count;
         if (!count)
             continue;

         OpcodeID opcodeID = opcodeSampleInfo[i].opcode;

         const char* opcodeName = opcodeNames[opcodeID];
         const char* opcodePadding = padOpcodeName(opcodeID, 28);
         double percentOfVM = (static_cast<double>(count) * 100) / m_opcodeSampleCount;
         double percentOfTotal = (static_cast<double>(count) * 100) / m_sampleCount;
         long long countInCTIFunctions = opcodeSampleInfo[i].countInCTIFunctions;
         double percentInCTIFunctions = (static_cast<double>(countInCTIFunctions) * 100) / count;
         debugDebugPrintf("%s:%s%-6lld %.3f%%\t%.3f%%\t  |   %-6lld %.3f%%\n", opcodeName, opcodePadding, count, percentOfVM, percentOfTotal, countInCTIFunctions, percentInCTIFunctions);
     }

     dataLogF("\n[*] Samples inside host code are not charged to any Bytecode.\n\n");
     dataLogF("\tSamples inside VM:\t\t%lld / %lld (%.3f%%)\n", m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_opcodeSampleCount) * 100) / m_sampleCount);
     dataLogF("\tSamples inside host code:\t%lld / %lld (%.3f%%)\n\n", m_sampleCount - m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_sampleCount - m_opcodeSampleCount) * 100) / m_sampleCount);
     dataLogF("\tsample count:\tsamples inside this opcode\n");
     dataLogF("\t%% of VM:\tsample count / all opcode samples\n");
     dataLogF("\t%% of total:\tsample count / all samples\n");
     dataLogF("\t--------------\n");
     dataLogF("\tcti count:\tsamples inside a CTI function called by this opcode\n");
     dataLogF("\tcti %% of self:\tcti count / sample count\n");

 #if ENABLE(CODEBLOCK_SAMPLING)

     // (3) Build and sort 'codeBlockSamples' array.

     int scopeCount = m_scopeSampleMap->size();
     Vector<ScriptSampleRecord*> codeBlockSamples(scopeCount);
     ScriptSampleRecordMap::iterator iter = m_scopeSampleMap->begin();
     for (int i = 0; i < scopeCount; ++i, ++iter)
         codeBlockSamples[i] = iter->value.get();

     qsort(codeBlockSamples.begin(), scopeCount, sizeof(ScriptSampleRecord*), compareScriptSampleRecords);

     // (4) Print data from 'codeBlockSamples' array.

     dataLogF("\nCodeBlock samples\n\n");

     for (int i = 0; i < scopeCount; ++i) {
         ScriptSampleRecord* record = codeBlockSamples[i];
         CodeBlock* codeBlock = record->m_codeBlock;

         double blockPercent = (record->m_sampleCount * 100.0) / m_sampleCount;

         if (blockPercent >= 1) {
             //Instruction* code = codeBlock->instructions().begin();
             dataLogF("#%d: %s:%d: %d / %lld (%.3f%%)\n", i + 1, record->m_executable->sourceURL().utf8().data(), codeBlock->lineNumberForBytecodeOffset(0), record->m_sampleCount, m_sampleCount, blockPercent);
             if (i < 10) {
                 HashMap<unsigned,unsigned> lineCounts;
                 codeBlock->dump(exec);

                 dataLogF("    Opcode and line number samples [*]\n\n");
                 for (unsigned op = 0; op < record->m_size; ++op) {
                     int count = record->m_samples[op];
                     if (count) {
                         dataLogF("    [% 4d] has sample count: % 4d\n", op, count);
                         unsigned line = codeBlock->lineNumberForBytecodeOffset(op);
                         lineCounts.set(line, (lineCounts.contains(line) ? lineCounts.get(line) : 0) + count);
                     }
                 }
                 dataLogF("\n");

                 int linesCount = lineCounts.size();
                 Vector<LineCountInfo> lineCountInfo(linesCount);
                 int lineno = 0;
                 for (HashMap<unsigned,unsigned>::iterator iter = lineCounts.begin(); iter != lineCounts.end(); ++iter, ++lineno) {
                     lineCountInfo[lineno].line = iter->key;
                     lineCountInfo[lineno].count = iter->value;
                 }

                 qsort(lineCountInfo.begin(), linesCount, sizeof(LineCountInfo), compareLineCountInfoSampling);

                 for (lineno = 0; lineno < linesCount; ++lineno) {
                     dataLogF("    Line #%d has sample count %d.\n", lineCountInfo[lineno].line, lineCountInfo[lineno].count);
                 }
                 dataLogF("\n");
                 dataLogF("    [*] Samples inside host code are charged to the calling Bytecode.\n");
                 dataLogF("        Samples on a call / return boundary are not charged to a specific opcode or line.\n\n");
                 dataLogF("            Samples on a call / return boundary: %d / %d (%.3f%%)\n\n", record->m_sampleCount - record->m_opcodeSampleCount, record->m_sampleCount, (static_cast<double>(record->m_sampleCount - record->m_opcodeSampleCount) * 100) / record->m_sampleCount);
             }
         }
     }
 #else
     UNUSED_PARAM(exec);
 #endif
 }

 #else

 void SamplingTool::dump(ExecState*)
 {
 }

 #endif

 } // namespace JSC
	/*
	* Copyright (C) 2008, 2009 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.
	*/

	#include "config.h"
	#include "SamplingTool.h"

	#include "CodeBlock.h"
	#include "Interpreter.h"
	#include "Opcode.h"

	#if !OS(WINDOWS)
	#include <unistd.h>
	#endif

	namespace JSC {

	#if ENABLE(SAMPLING_FLAGS)

	void SamplingFlags::sample()
	{
	uint32_t mask = static_cast<uint32_t>(1 << 31);
	unsigned index;

	for (index = 0; index < 32; ++index) {
	if (mask & s_flags)
	break;
	mask >>= 1;
	}

	s_flagCounts[32 - index]++;
	}

	void SamplingFlags::start()
	{
	for (unsigned i = 0; i <= 32; ++i)
	s_flagCounts[i] = 0;
	}
	void SamplingFlags::stop()
	{
	uint64_t total = 0;
	for (unsigned i = 0; i <= 32; ++i)
	total += s_flagCounts[i];

	if (total) {
	dataLogF("\nSamplingFlags: sample counts with flags set: (%lld total)\n", total);
	for (unsigned i = 0; i <= 32; ++i) {
	if (s_flagCounts[i])
	dataLogF(" [ %02d ] : %lld\t\t(%03.2f%%)\n", i, s_flagCounts[i], (100.0 * s_flagCounts[i]) / total);
	}
	dataLogF("\n");
	} else
	dataLogF("\nSamplingFlags: no samples.\n\n");
	}
	uint64_t SamplingFlags::s_flagCounts[33];

	#else
	void SamplingFlags::start() {}
	void SamplingFlags::stop() {}
	#endif

	#if ENABLE(SAMPLING_REGIONS)
	volatile uintptr_t SamplingRegion::s_currentOrReserved;
	Spectrum<const char> SamplingRegion::s_spectrum;
	unsigned long SamplingRegion::s_noneOfTheAbove;
	unsigned SamplingRegion::s_numberOfSamplesSinceDump;

	SamplingRegion::Locker::Locker()
	{
	uintptr_t previous;
	while (true) {
	previous = s_currentOrReserved;
	if (previous & 1) {
	#if OS(UNIX)
	sched_yield();
	#endif
	continue;
	}
	if (WTF::weakCompareAndSwapUIntPtr(&s_currentOrReserved, previous, previous \| 1))
	break;
	}
	}

	SamplingRegion::Locker::~Locker()
	{
	// We don't need the CAS, but we do it out of an
	// abundance of caution (and because it gives us a memory fence, which is
	// never bad).
	uintptr_t previous;
	do {
	previous = s_currentOrReserved;
	} while (!WTF::weakCompareAndSwapUIntPtr(&s_currentOrReserved, previous, previous & ~1));
	}

	void SamplingRegion::sample()
	{
	// Make sure we lock s_current.
	Locker locker;

	// Create a spectrum if we don't have one already.
	if (!s_spectrum)
	s_spectrum = new Spectrum<const char*>();

	ASSERT(s_currentOrReserved & 1);

	// Walk the region stack, and record each region we see.
	SamplingRegion* region = bitwise_cast<SamplingRegion*>(s_currentOrReserved & ~1);
	if (region) {
	for (; region; region = region->m_previous)
	s_spectrum->add(region->m_name);
	} else
	s_noneOfTheAbove++;

	if (s_numberOfSamplesSinceDump++ == SamplingThread::s_hertz) {
	s_numberOfSamplesSinceDump = 0;
	dumpInternal();
	}
	}

	void SamplingRegion::dump()
	{
	Locker locker;

	dumpInternal();
	}

	void SamplingRegion::dumpInternal()
	{
	if (!s_spectrum) {
	dataLogF("\nSamplingRegion: was never sampled.\n\n");
	return;
	}

	Vector<Spectrum<const char*>::KeyAndCount> list = s_spectrum->buildList();

	unsigned long total = s_noneOfTheAbove;
	for (unsigned i = list.size(); i--;)
	total += list[i].count;

	dataLogF("\nSamplingRegion: sample counts for regions: (%lu samples)\n", total);

	for (unsigned i = list.size(); i--;)
	dataLogF(" %3.2lf%% %s\n", (100.0 * list[i].count) / total, list[i].key);
	}
	#else // ENABLE(SAMPLING_REGIONS)
	void SamplingRegion::dump() { }
	#endif // ENABLE(SAMPLING_REGIONS)

	/*
	Start with flag 16 set.
	By doing this the monitoring of lower valued flags will be masked out
	until flag 16 is explictly cleared.
	*/
	uint32_t SamplingFlags::s_flags = 1 << 15;


	#if OS(WINDOWS)

	static void sleepForMicroseconds(unsigned us)
	{
	unsigned ms = us / 1000;
	if (us && !ms)
	ms = 1;
	Sleep(ms);
	}

	#else

	static void sleepForMicroseconds(unsigned us)
	{
	usleep(us);
	}

	#endif

	static inline unsigned hertz2us(unsigned hertz)
	{
	return 1000000 / hertz;
	}


	SamplingTool* SamplingTool::s_samplingTool = 0;


	bool SamplingThread::s_running = false;
	unsigned SamplingThread::s_hertz = 10000;
	ThreadIdentifier SamplingThread::s_samplingThread;

	void SamplingThread::threadStartFunc(void*)
	{
	while (s_running) {
	sleepForMicroseconds(hertz2us(s_hertz));

	#if ENABLE(SAMPLING_FLAGS)
	SamplingFlags::sample();
	#endif
	#if ENABLE(SAMPLING_REGIONS)
	SamplingRegion::sample();
	#endif
	#if ENABLE(OPCODE_SAMPLING)
	SamplingTool::sample();
	#endif
	}
	}


	void SamplingThread::start(unsigned hertz)
	{
	ASSERT(!s_running);
	s_running = true;
	s_hertz = hertz;

	s_samplingThread = createThread(threadStartFunc, 0, "JavaScriptCore::Sampler");
	}

	void SamplingThread::stop()
	{
	ASSERT(s_running);
	s_running = false;
	waitForThreadCompletion(s_samplingThread);
	}


	void ScriptSampleRecord::sample(CodeBlock* codeBlock, Instruction* vPC)
	{
	if (!m_samples) {
	m_size = codeBlock->instructions().size();
	m_samples = static_cast<int*>(calloc(m_size, sizeof(int)));
	m_codeBlock = codeBlock;
	}

	++m_sampleCount;

	unsigned offest = vPC - codeBlock->instructions().begin();
	// Since we don't read and write codeBlock and vPC atomically, this check
	// can fail if we sample mid op_call / op_ret.
	if (offest < m_size) {
	m_samples[offest]++;
	m_opcodeSampleCount++;
	}
	}

	void SamplingTool::doRun()
	{
	Sample sample(m_sample, m_codeBlock);
	++m_sampleCount;

	if (sample.isNull())
	return;

	if (!sample.inHostFunction()) {
	unsigned opcodeID = m_interpreter->getOpcodeID(sample.vPC()[0].u.opcode);

	++m_opcodeSampleCount;
	++m_opcodeSamples[opcodeID];

	if (sample.inCTIFunction())
	m_opcodeSamplesInCTIFunctions[opcodeID]++;
	}

	#if ENABLE(CODEBLOCK_SAMPLING)
	if (CodeBlock* codeBlock = sample.codeBlock()) {
	MutexLocker locker(m_scriptSampleMapMutex);
	ScriptSampleRecord* record = m_scopeSampleMap->get(codeBlock->ownerExecutable());
	ASSERT(record);
	record->sample(codeBlock, sample.vPC());
	}
	#endif
	}

	void SamplingTool::sample()
	{
	s_samplingTool->doRun();
	}

	void SamplingTool::notifyOfScope(JSGlobalData& globalData, ScriptExecutable* script)
	{
	#if ENABLE(CODEBLOCK_SAMPLING)
	MutexLocker locker(m_scriptSampleMapMutex);
	m_scopeSampleMap->set(script, adoptPtr(new ScriptSampleRecord(globalData, script)));
	#else
	UNUSED_PARAM(globalData);
	UNUSED_PARAM(script);
	#endif
	}

	void SamplingTool::setup()
	{
	s_samplingTool = this;
	}

	#if ENABLE(OPCODE_SAMPLING)

	struct OpcodeSampleInfo {
	OpcodeID opcode;
	long long count;
	long long countInCTIFunctions;
	};

	struct LineCountInfo {
	unsigned line;
	unsigned count;
	};

	static int compareOpcodeIndicesSampling(const void* left, const void* right)
	{
	const OpcodeSampleInfo* leftSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(left);
	const OpcodeSampleInfo* rightSampleInfo = reinterpret_cast<const OpcodeSampleInfo*>(right);

	return (leftSampleInfo->count < rightSampleInfo->count) ? 1 : (leftSampleInfo->count > rightSampleInfo->count) ? -1 : 0;
	}

	#if ENABLE(CODEBLOCK_SAMPLING)
	static int compareLineCountInfoSampling(const void* left, const void* right)
	{
	const LineCountInfo* leftLineCount = reinterpret_cast<const LineCountInfo*>(left);
	const LineCountInfo* rightLineCount = reinterpret_cast<const LineCountInfo*>(right);

	return (leftLineCount->line > rightLineCount->line) ? 1 : (leftLineCount->line < rightLineCount->line) ? -1 : 0;
	}

	static int compareScriptSampleRecords(const void* left, const void* right)
	{
	const ScriptSampleRecord* const leftValue = static_cast<const ScriptSampleRecord const *>(left);
	const ScriptSampleRecord* const rightValue = static_cast<const ScriptSampleRecord const *>(right);

	return (leftValue->m_sampleCount < rightValue->m_sampleCount) ? 1 : (leftValue->m_sampleCount > rightValue->m_sampleCount) ? -1 : 0;
	}
	#endif

	void SamplingTool::dump(ExecState* exec)
	{
	// Tidies up SunSpider output by removing short scripts - such a small number of samples would likely not be useful anyhow.
	if (m_sampleCount < 10)
	return;

	// (1) Build and sort 'opcodeSampleInfo' array.

	OpcodeSampleInfo opcodeSampleInfo[numOpcodeIDs];
	for (int i = 0; i < numOpcodeIDs; ++i) {
	opcodeSampleInfo[i].opcode = static_cast<OpcodeID>(i);
	opcodeSampleInfo[i].count = m_opcodeSamples[i];
	opcodeSampleInfo[i].countInCTIFunctions = m_opcodeSamplesInCTIFunctions[i];
	}

	qsort(opcodeSampleInfo, numOpcodeIDs, sizeof(OpcodeSampleInfo), compareOpcodeIndicesSampling);

	// (2) Print Opcode sampling results.

	dataLogF("\nBytecode samples [*]\n");
	dataLogF(" sample %% of %% of \| cti cti %%\n");
	dataLogF("opcode count VM total \| count of self\n");
	dataLogF("------------------------------------------------------- \| ----------------\n");

	for (int i = 0; i < numOpcodeIDs; ++i) {
	long long count = opcodeSampleInfo[i].count;
	if (!count)
	continue;

	OpcodeID opcodeID = opcodeSampleInfo[i].opcode;

	const char* opcodeName = opcodeNames[opcodeID];
	const char* opcodePadding = padOpcodeName(opcodeID, 28);
	double percentOfVM = (static_cast<double>(count) * 100) / m_opcodeSampleCount;
	double percentOfTotal = (static_cast<double>(count) * 100) / m_sampleCount;
	long long countInCTIFunctions = opcodeSampleInfo[i].countInCTIFunctions;
	double percentInCTIFunctions = (static_cast<double>(countInCTIFunctions) * 100) / count;
	debugDebugPrintf("%s:%s%-6lld %.3f%%\t%.3f%%\t \| %-6lld %.3f%%\n", opcodeName, opcodePadding, count, percentOfVM, percentOfTotal, countInCTIFunctions, percentInCTIFunctions);
	}

	dataLogF("\n[*] Samples inside host code are not charged to any Bytecode.\n\n");
	dataLogF("\tSamples inside VM:\t\t%lld / %lld (%.3f%%)\n", m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_opcodeSampleCount) * 100) / m_sampleCount);
	dataLogF("\tSamples inside host code:\t%lld / %lld (%.3f%%)\n\n", m_sampleCount - m_opcodeSampleCount, m_sampleCount, (static_cast<double>(m_sampleCount - m_opcodeSampleCount) * 100) / m_sampleCount);
	dataLogF("\tsample count:\tsamples inside this opcode\n");
	dataLogF("\t%% of VM:\tsample count / all opcode samples\n");
	dataLogF("\t%% of total:\tsample count / all samples\n");
	dataLogF("\t--------------\n");
	dataLogF("\tcti count:\tsamples inside a CTI function called by this opcode\n");
	dataLogF("\tcti %% of self:\tcti count / sample count\n");

	#if ENABLE(CODEBLOCK_SAMPLING)

	// (3) Build and sort 'codeBlockSamples' array.

	int scopeCount = m_scopeSampleMap->size();
	Vector<ScriptSampleRecord*> codeBlockSamples(scopeCount);
	ScriptSampleRecordMap::iterator iter = m_scopeSampleMap->begin();
	for (int i = 0; i < scopeCount; ++i, ++iter)
	codeBlockSamples[i] = iter->value.get();

	qsort(codeBlockSamples.begin(), scopeCount, sizeof(ScriptSampleRecord*), compareScriptSampleRecords);

	// (4) Print data from 'codeBlockSamples' array.

	dataLogF("\nCodeBlock samples\n\n");

	for (int i = 0; i < scopeCount; ++i) {
	ScriptSampleRecord* record = codeBlockSamples[i];
	CodeBlock* codeBlock = record->m_codeBlock;

	double blockPercent = (record->m_sampleCount * 100.0) / m_sampleCount;

	if (blockPercent >= 1) {
	//Instruction* code = codeBlock->instructions().begin();
	dataLogF("#%d: %s:%d: %d / %lld (%.3f%%)\n", i + 1, record->m_executable->sourceURL().utf8().data(), codeBlock->lineNumberForBytecodeOffset(0), record->m_sampleCount, m_sampleCount, blockPercent);
	if (i < 10) {
	HashMap<unsigned,unsigned> lineCounts;
	codeBlock->dump(exec);

	dataLogF(" Opcode and line number samples [*]\n\n");
	for (unsigned op = 0; op < record->m_size; ++op) {
	int count = record->m_samples[op];
	if (count) {
	dataLogF(" [% 4d] has sample count: % 4d\n", op, count);
	unsigned line = codeBlock->lineNumberForBytecodeOffset(op);
	lineCounts.set(line, (lineCounts.contains(line) ? lineCounts.get(line) : 0) + count);
	}
	}
	dataLogF("\n");

	int linesCount = lineCounts.size();
	Vector<LineCountInfo> lineCountInfo(linesCount);
	int lineno = 0;
	for (HashMap<unsigned,unsigned>::iterator iter = lineCounts.begin(); iter != lineCounts.end(); ++iter, ++lineno) {
	lineCountInfo[lineno].line = iter->key;
	lineCountInfo[lineno].count = iter->value;
	}

	qsort(lineCountInfo.begin(), linesCount, sizeof(LineCountInfo), compareLineCountInfoSampling);

	for (lineno = 0; lineno < linesCount; ++lineno) {
	dataLogF(" Line #%d has sample count %d.\n", lineCountInfo[lineno].line, lineCountInfo[lineno].count);
	}
	dataLogF("\n");
	dataLogF(" [*] Samples inside host code are charged to the calling Bytecode.\n");
	dataLogF(" Samples on a call / return boundary are not charged to a specific opcode or line.\n\n");
	dataLogF(" Samples on a call / return boundary: %d / %d (%.3f%%)\n\n", record->m_sampleCount - record->m_opcodeSampleCount, record->m_sampleCount, (static_cast<double>(record->m_sampleCount - record->m_opcodeSampleCount) * 100) / record->m_sampleCount);
	}
	}
	}
	#else
	UNUSED_PARAM(exec);
	#endif
	}

	#else

	void SamplingTool::dump(ExecState*)
	{
	}

	#endif

	} // namespace JSC