Changeset 113552 in webkit for trunk/Source/JavaScriptCore/bytecode/DFGExitProfile.h

Timestamp:

Apr 8, 2012, 1:46:12 PM (13 years ago)

Author:

[email protected]

Message:

Forced OSR exits should lead to recompilation based on count, not rate
​https://bugs.webkit.org/show_bug.cgi?id=83247
<rdar://problem/10720925>

Reviewed by Geoff Garen.

Track which OSR exits happen because of inadequate coverage. Count them
separately. If the count reaches a threshold, immediately trigger
reoptimization.

This is in contrast to the recompilation trigger for all other OSR exits.
Normally recomp is triggered when the exit rate exceeds a certain ratio.

Looks like a slight V8 speedup (sub 1%).

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::CodeBlock):

• bytecode/CodeBlock.h:

(JSC::CodeBlock::forcedOSRExitCounter):
(JSC::CodeBlock::addressOfForcedOSRExitCounter):
(JSC::CodeBlock::offsetOfForcedOSRExitCounter):
(JSC::CodeBlock::shouldReoptimizeNow):
(JSC::CodeBlock::shouldReoptimizeFromLoopNow):
(CodeBlock):

• bytecode/DFGExitProfile.h:

(JSC::DFG::exitKindToString):

• dfg/DFGOSRExitCompiler.cpp:

(JSC::DFG::OSRExitCompiler::handleExitCounts):
(DFG):

• dfg/DFGOSRExitCompiler.h:

(OSRExitCompiler):

• dfg/DFGOSRExitCompiler32_64.cpp:

(JSC::DFG::OSRExitCompiler::compileExit):

• dfg/DFGOSRExitCompiler64.cpp:

(JSC::DFG::OSRExitCompiler::compileExit):

• dfg/DFGOperations.cpp:
• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::compileGetIndexedPropertyStorage):

• dfg/DFGSpeculativeJIT32_64.cpp:

(JSC::DFG::SpeculativeJIT::compile):

• dfg/DFGSpeculativeJIT64.cpp:

(JSC::DFG::SpeculativeJIT::compile):

• runtime/Options.cpp:

(Options):
(JSC::Options::initializeOptions):

• runtime/Options.h:

(Options):

File:

• trunk/Source/JavaScriptCore/bytecode/DFGExitProfile.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/bytecode/DFGExitProfile.h

@@ -39 +39 @@
     Overflow, // We exited because of overflow.
     NegativeZero, // We exited because we encountered negative zero.
+    InadequateCoverage, // We exited because we ended up in code that didn't have profiling coverage.
     Uncountable, // We exited for none of the above reasons, and we should not count it. Most uses of this should be viewed as a FIXME.
 };
@@ -55 +56 @@
     case NegativeZero:
         return "NegativeZero";
+    case InadequateCoverage:
+        return "InadequateCoverage";
     default:
         return "Unknown";