commit d5d9bae290b69340d2d3ba3fe0ad4a70354ee448
author fpizlo@apple.com <fpizlo@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> Sat Aug 18 06:01:33 2012 +0000
committer fpizlo@apple.com <fpizlo@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> Sat Aug 18 06:01:33 2012 +0000
tree 01b8ed95708531eb71afb30443ed16929890997c
parent bfc750f3ccb8bb169580524db6eec888c3df262a

DFG CSE should be more honest about when it changed the IR
https://bugs.webkit.org/show_bug.cgi?id=94408

Reviewed by Geoffrey Garen.

The CSE phase now always returns true if it changed the IR.

* dfg/DFGCSEPhase.cpp:
(JSC::DFG::CSEPhase::setReplacement):
(JSC::DFG::CSEPhase::eliminate):
(JSC::DFG::CSEPhase::performNodeCSE):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@125964 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/JavaScriptCore/ChangeLog

diff --git a/Source/JavaScriptCore/ChangeLog b/Source/JavaScriptCore/ChangeLog
index 2522b03..695778a 100644
--- a/Source/JavaScriptCore/ChangeLog
+++ b/Source/JavaScriptCore/ChangeLog
@@ -1,5 +1,19 @@
 2012-08-17  Filip Pizlo  <fpizlo@apple.com>
 
+        DFG CSE should be more honest about when it changed the IR
+        https://bugs.webkit.org/show_bug.cgi?id=94408
+
+        Reviewed by Geoffrey Garen.
+
+        The CSE phase now always returns true if it changed the IR.
+
+        * dfg/DFGCSEPhase.cpp:
+        (JSC::DFG::CSEPhase::setReplacement):
+        (JSC::DFG::CSEPhase::eliminate):
+        (JSC::DFG::CSEPhase::performNodeCSE):
+
+2012-08-17  Filip Pizlo  <fpizlo@apple.com>
+
         DFG is still too pessimistic about what constitutes a side-effect on array accesses
         https://bugs.webkit.org/show_bug.cgi?id=94309
 

Source/JavaScriptCore/dfg/DFGCSEPhase.cpp

diff --git a/Source/JavaScriptCore/dfg/DFGCSEPhase.cpp b/Source/JavaScriptCore/dfg/DFGCSEPhase.cpp
index a5215cc..2bf1ef9d 100644
--- a/Source/JavaScriptCore/dfg/DFGCSEPhase.cpp
+++ b/Source/JavaScriptCore/dfg/DFGCSEPhase.cpp
@@ -843,6 +843,8 @@
         // At this point we will eliminate all references to this node.
         m_replacements[m_compileIndex] = replacement;
         
+        m_changed = true;
+        
         return true;
     }
     
@@ -856,6 +858,8 @@
         ASSERT(node.refCount() == 1);
         ASSERT(node.mustGenerate());
         node.setOpAndDefaultFlags(Phantom);
+        
+        m_changed = true;
     }
     
     void eliminate(NodeIndex nodeIndex, NodeType phantomType = Phantom)
@@ -867,6 +871,8 @@
             return;
         ASSERT(node.mustGenerate());
         node.setOpAndDefaultFlags(phantomType);
+        
+        m_changed = true;
     }
     
     void performNodeCSE(Node& node)
@@ -982,7 +988,7 @@
             
         case GetLocalUnlinked: {
             NodeIndex relevantLocalOpIgnored;
-            m_changed |= setReplacement(getLocalLoadElimination(node.unlinkedLocal(), relevantLocalOpIgnored, true));
+            setReplacement(getLocalLoadElimination(node.unlinkedLocal(), relevantLocalOpIgnored, true));
             break;
         }