Changeset 118278 in webkit for trunk/Source/JavaScriptCore/bytecode/DFGExitProfile.h

Timestamp:

May 23, 2012, 5:18:55 PM (13 years ago)

Author:

[email protected]

Message:

DFG should optimize inlined uses of arguments.length and arguments[i]
​https://bugs.webkit.org/show_bug.cgi?id=86327

Reviewed by Gavin Barraclough.

Merged r117017 from dfgopt.

Turns inlined uses of arguments.length into a constant.

Turns inlined uses of arguments[constant] into a direct reference to the
argument.

Big win on micro-benchmarks. Not yet a win on V8 because the hot uses of
arguments.length and arguments[i] are aliased. I'll leave the aliasing
optimizations to a later patch.

• CMakeLists.txt:
• GNUmakefile.list.am:
• JavaScriptCore.xcodeproj/project.pbxproj:
• Target.pri:
• bytecode/DFGExitProfile.h:

(FrequentExitSite):
(JSC::DFG::FrequentExitSite::FrequentExitSite):
(JSC::DFG::QueryableExitProfile::hasExitSite):
(QueryableExitProfile):

• dfg/DFGAbstractState.cpp:

(JSC::DFG::AbstractState::execute):

• dfg/DFGArgumentsSimplificationPhase.cpp: Added.

(DFG):
(ArgumentsSimplificationPhase):
(JSC::DFG::ArgumentsSimplificationPhase::ArgumentsSimplificationPhase):
(JSC::DFG::ArgumentsSimplificationPhase::run):
(JSC::DFG::performArgumentsSimplification):

• dfg/DFGArgumentsSimplificationPhase.h: Added.

(DFG):

• dfg/DFGAssemblyHelpers.cpp:

(JSC::DFG::AssemblyHelpers::executableFor):
(DFG):

• dfg/DFGAssemblyHelpers.h:

(AssemblyHelpers):

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::parseBlock):
(JSC::DFG::ByteCodeParser::InlineStackEntry::InlineStackEntry):

• dfg/DFGCSEPhase.cpp:

(JSC::DFG::CSEPhase::getLocalLoadElimination):
(JSC::DFG::CSEPhase::performNodeCSE):

• dfg/DFGDriver.cpp:

(JSC::DFG::compile):

• dfg/DFGGraph.h:

(JSC::DFG::Graph::Graph):
(JSC::DFG::Graph::executableFor):
(Graph):
(JSC::DFG::Graph::clobbersWorld):

• dfg/DFGNode.h:

(JSC::DFG::Node::convertToConstant):
(JSC::DFG::Node::convertToGetLocalUnlinked):
(Node):
(JSC::DFG::Node::unlinkedLocal):

• dfg/DFGNodeType.h:

(DFG):

• dfg/DFGOSRExit.cpp:

(JSC::DFG::OSRExit::considerAddingAsFrequentExitSiteSlow):

• dfg/DFGPredictionPropagationPhase.cpp:

(JSC::DFG::PredictionPropagationPhase::propagate):

• dfg/DFGSpeculativeJIT32_64.cpp:

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

• dfg/DFGSpeculativeJIT64.cpp:

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

File:

• trunk/Source/JavaScriptCore/bytecode/DFGExitProfile.h (modified) (3 diffs)

trunk/Source/JavaScriptCore/bytecode/DFGExitProfile.h

@@ -40 +40 @@
     NegativeZero, // We exited because we encountered negative zero.
     InadequateCoverage, // We exited because we ended up in code that didn't have profiling coverage.
+    ArgumentsEscaped, // We exited because arguments escaped but we didn't expect them to.
     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.
 };
@@ -97 +98 @@
     }
     
+    // Use this constructor if you wish for the exit site to be counted globally within its
+    // code block.
+    explicit FrequentExitSite(ExitKind kind)
+        : m_bytecodeOffset(0)
+        , m_kind(kind)
+    {
+        ASSERT(exitKindIsCountable(kind));
+    }
+    
     bool operator!() const
     {
@@ -179 +189 @@
     }
     
+    bool hasExitSite(ExitKind kind) const
+    {
+        return hasExitSite(FrequentExitSite(kind));
+    }
+    
     bool hasExitSite(unsigned bytecodeIndex, ExitKind kind) const
     {