Changeset 222871 in webkit for trunk/Source/JavaScriptCore/assembler/ProbeStack.h

Timestamp:

Oct 4, 2017, 1:00:01 PM (8 years ago)

Author:

[email protected]

Message:

Add support for using Probe DFG OSR Exit behind a runtime flag.
​https://bugs.webkit.org/show_bug.cgi?id=177844
<rdar://problem/34801425>

Reviewed by Saam Barati.

Source/JavaScriptCore:

This is based on the code originally posted in ​https://bugs.webkit.org/show_bug.cgi?id=175144
(in r221774 and r221832) with some optimizations and bug fixes added. The probe
based DFG OSR Exit is only enabled if Options::useProbeOSRExit() is true. We're
landing this behind an option switch to make it easier to tune performance using
the probe based OSR exit.

• JavaScriptCore.xcodeproj/project.pbxproj:
• assembler/MacroAssembler.cpp:

(JSC::stdFunctionCallback):

• assembler/MacroAssemblerPrinter.cpp:

(JSC::Printer::printCallback):

• assembler/ProbeContext.cpp:

(JSC::Probe::executeProbe):
(JSC::Probe::flushDirtyStackPages):

• assembler/ProbeContext.h:

(JSC::Probe::Context::Context):
(JSC::Probe::Context::arg):

• assembler/ProbeFrame.h: Added.

(JSC::Probe::Frame::Frame):
(JSC::Probe::Frame::argument):
(JSC::Probe::Frame::operand):
(JSC::Probe::Frame::setArgument):
(JSC::Probe::Frame::setOperand):
(JSC::Probe::Frame::get):
(JSC::Probe::Frame::set):

• assembler/ProbeStack.cpp:

(JSC::Probe::Page::lowWatermarkFromVisitingDirtyChunks):
(JSC::Probe::Stack::Stack):
(JSC::Probe::Stack::lowWatermarkFromVisitingDirtyPages):

• assembler/ProbeStack.h:

(JSC::Probe::Stack::Stack):
(JSC::Probe::Stack::lowWatermark):
(JSC::Probe::Stack::set):
(JSC::Probe::Stack::savedStackPointer const):
(JSC::Probe::Stack::setSavedStackPointer):
(JSC::Probe::Stack::newStackPointer const): Deleted.
(JSC::Probe::Stack::setNewStackPointer): Deleted.

• bytecode/ArrayProfile.h:

(JSC::ArrayProfile::observeArrayMode):

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::updateOSRExitCounterAndCheckIfNeedToReoptimize):

• bytecode/CodeBlock.h:

(JSC::CodeBlock::addressOfOSRExitCounter): Deleted.

• bytecode/ExecutionCounter.h:

(JSC::ExecutionCounter::hasCrossedThreshold const):
(JSC::ExecutionCounter::setNewThresholdForOSRExit):

• bytecode/MethodOfGettingAValueProfile.cpp:

(JSC::MethodOfGettingAValueProfile::reportValue):

• bytecode/MethodOfGettingAValueProfile.h:
• dfg/DFGDriver.cpp:

(JSC::DFG::compileImpl):

• dfg/DFGJITCompiler.cpp:

(JSC::DFG::JITCompiler::linkOSRExits):
(JSC::DFG::JITCompiler::link):

• dfg/DFGOSRExit.cpp:

(JSC::DFG::jsValueFor):
(JSC::DFG::restoreCalleeSavesFor):
(JSC::DFG::saveCalleeSavesFor):
(JSC::DFG::restoreCalleeSavesFromVMEntryFrameCalleeSavesBuffer):
(JSC::DFG::copyCalleeSavesToVMEntryFrameCalleeSavesBuffer):
(JSC::DFG::saveOrCopyCalleeSavesFor):
(JSC::DFG::createDirectArgumentsDuringExit):
(JSC::DFG::createClonedArgumentsDuringExit):
(JSC::DFG::emitRestoreArguments):
(JSC::DFG::OSRExit::executeOSRExit):
(JSC::DFG::reifyInlinedCallFrames):
(JSC::DFG::adjustAndJumpToTarget):
(JSC::DFG::printOSRExit):

• dfg/DFGOSRExit.h:

(JSC::DFG::OSRExitState::OSRExitState):

• dfg/DFGThunks.cpp:

(JSC::DFG::osrExitThunkGenerator):

• dfg/DFGThunks.h:
• dfg/DFGVariableEventStream.cpp:

(JSC::DFG::tryToSetConstantRecovery):
(JSC::DFG::VariableEventStream::reconstruct const):
(JSC::DFG::VariableEventStream::tryToSetConstantRecovery const): Deleted.

• dfg/DFGVariableEventStream.h:
• profiler/ProfilerOSRExit.h:

(JSC::Profiler::OSRExit::incCount):

• runtime/JSCJSValue.h:
• runtime/JSCJSValueInlines.h:
• runtime/Options.h:

Tools:

Enable --useProbeOSrExit=true for dfg-eager and ftl-no-cjit-validate-sampling-profiler
test configurations.

• Scripts/run-jsc-stress-tests:

File:

• trunk/Source/JavaScriptCore/assembler/ProbeStack.h (modified) (5 diffs)

trunk/Source/JavaScriptCore/assembler/ProbeStack.h

@@ -96 +96 @@
     }
 
+    void* lowWatermarkFromVisitingDirtyChunks();
+
 private:
     uint64_t dirtyBitFor(void* logicalAddress)
@@ -147 +149 @@
 public:
     Stack()
-        : m_lowWatermark(reinterpret_cast<void*>(-1))
-        , m_stackBounds(Thread::current().stack())
+        : m_stackBounds(Thread::current().stack())
     { }
     Stack(Stack&& other);
 
-    void* lowWatermark()
-    {
-        // We use the chunkAddress for the low watermark because we'll be doing write backs
-        // to the stack in increments of chunks. Hence, we'll treat the lowest address of
-        // the chunk as the low watermark of any given set address.
-        return Page::chunkAddressFor(m_lowWatermark);
+    void* lowWatermarkFromVisitingDirtyPages();
+    void* lowWatermark(void* stackPointer)
+    {
+        ASSERT(Page::chunkAddressFor(stackPointer) == lowWatermarkFromVisitingDirtyPages());
+        return Page::chunkAddressFor(stackPointer);
     }
 
@@ -177 +177 @@
         Page* page = pageFor(address);
         page->set<T>(address, value);
-
-        if (address < m_lowWatermark)
-            m_lowWatermark = address;
     }
 
@@ -190 +187 @@
     JS_EXPORT_PRIVATE Page* ensurePageFor(void* address);
 
-    void* newStackPointer() const { return m_newStackPointer; };
-    void setNewStackPointer(void* sp) { m_newStackPointer = sp; };
+    void* savedStackPointer() const { return m_savedStackPointer; }
+    void setSavedStackPointer(void* sp) { m_savedStackPointer = sp; }
 
     bool hasWritesToFlush();
@@ -208 +205 @@
     }
 
-    void* m_newStackPointer { nullptr };
-    void* m_lowWatermark;
+    void* m_savedStackPointer { nullptr };
 
     // A cache of the last accessed page details for quick access.