Changeset 102489 in webkit for trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp

Timestamp:

Dec 9, 2011, 4:09:55 PM (13 years ago)

Author:

[email protected]

Message:

DFG's interpretation of rare case profiles should be frequency-based not count-based
​https://bugs.webkit.org/show_bug.cgi?id=74170

Reviewed by Geoff Garen.

DFG optimizes for rare cases only when the rare case counter is above some threshold
and it also constitutes a large enough fraction of total function executions. Also
added some minor debug logic.

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::CodeBlock):

• bytecode/CodeBlock.h:

(JSC::CodeBlock::likelyToTakeSlowCase):
(JSC::CodeBlock::couldTakeSlowCase):
(JSC::CodeBlock::likelyToTakeSpecialFastCase):
(JSC::CodeBlock::likelyToTakeDeepestSlowCase):
(JSC::CodeBlock::likelyToTakeAnySlowCase):
(JSC::CodeBlock::executionEntryCount):

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::makeSafe):
(JSC::DFG::ByteCodeParser::makeDivSafe):
(JSC::DFG::ByteCodeParser::handleCall):
(JSC::DFG::ByteCodeParser::parseBlock):

• dfg/DFGDriver.cpp:

(JSC::DFG::compile):

• jit/JIT.cpp:

(JSC::JIT::privateCompile):

• runtime/Heuristics.cpp:

(JSC::Heuristics::initializeHeuristics):

• runtime/Heuristics.h:

File:

• trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/bytecode/CodeBlock.cpp

@@ -1434 +1434 @@
     , m_globalResolveInfos(other.m_globalResolveInfos)
 #endif
+#if ENABLE(VALUE_PROFILER)
+    , m_executionEntryCount(0)
+#endif
     , m_jumpTargets(other.m_jumpTargets)
     , m_loopTargets(other.m_loopTargets)
@@ -1482 +1485 @@
     , m_source(sourceProvider)
     , m_sourceOffset(sourceOffset)
+#if ENABLE(VALUE_PROFILER)
+    , m_executionEntryCount(0)
+#endif
     , m_symbolTable(symTab)
     , m_alternative(alternative)
@@ -2236 +2242 @@
 #endif
 
-#if ENABLE(VALUE_PROFILER)
-void CodeBlock::resetRareCaseProfiles()
-{
-    for (unsigned i = 0; i < numberOfRareCaseProfiles(); ++i)
-        rareCaseProfile(i)->m_counter = 0;
-    for (unsigned i = 0; i < numberOfSpecialFastCaseProfiles(); ++i)
-        specialFastCaseProfile(i)->m_counter = 0;
-}
-#endif
-
 #if ENABLE(VERBOSE_VALUE_PROFILE)
 void CodeBlock::dumpValueProfiles()