Changeset 192529 in webkit for trunk/Source/JavaScriptCore/dfg/DFGCriticalEdgeBreakingPhase.cpp

Timestamp:

Nov 17, 2015, 1:41:43 PM (10 years ago)

Author:

[email protected]

Message:

It's best for the DFG to always have some guess of basic block frequency
​https://bugs.webkit.org/show_bug.cgi?id=151350

Reviewed by Geoffrey Garen.

It'll simplify things for B3 if we always have some estimate of block frequency, even if it's not
a great estimate. Using NaN as an estimate is probably worse than using any non-NaN number.

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::inlineCall):
(JSC::DFG::ByteCodeParser::handleInlining):
(JSC::DFG::ByteCodeParser::parseCodeBlock):

• dfg/DFGCriticalEdgeBreakingPhase.cpp:

(JSC::DFG::CriticalEdgeBreakingPhase::breakCriticalEdge):

• dfg/DFGLoopPreHeaderCreationPhase.cpp:

(JSC::DFG::createPreHeader):

File:

• trunk/Source/JavaScriptCore/dfg/DFGCriticalEdgeBreakingPhase.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/dfg/DFGCriticalEdgeBreakingPhase.cpp

@@ -74 +74 @@
     void breakCriticalEdge(BasicBlock* predecessor, BasicBlock** successor)
     {
-        // Note that we pass NaN for the count of the critical edge block, because we honestly
-        // don't know its execution frequency.
-        BasicBlock* pad = m_insertionSet.insertBefore(*successor, PNaN);
+        BasicBlock* pad = m_insertionSet.insertBefore(*successor, (*successor)->executionCount);
         pad->appendNode(
             m_graph, SpecNone, Jump, (*successor)->at(0)->origin, OpInfo(*successor));