commit 9775655d6710da78d3c82a14893b05cfa147ea8c
author fpizlo@apple.com <fpizlo@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> Thu Jan 02 20:15:25 2014 +0000
committer fpizlo@apple.com <fpizlo@apple.com@268f45cc-cd09-0410-ab3c-d52691b4dbfc> Thu Jan 02 20:15:25 2014 +0000
tree 906bf4f49eafcd5495f8289b15b622f162c6d5c2
parent 04118560ac44017fc69277c6793def6b7172947f

Rationalize DFG DCE
https://bugs.webkit.org/show_bug.cgi?id=125523

Reviewed by Mark Hahnenberg.
        
Adds the ability to DCE more things. It's now the case that if a node is completely
pure, we clear NodeMustGenerate and the node becomes a DCE candidate.

* dfg/DFGAbstractInterpreterInlines.h:
(JSC::DFG::AbstractInterpreter<AbstractStateType>::executeEffects):
* dfg/DFGCSEPhase.cpp:
(JSC::DFG::CSEPhase::performNodeCSE):
* dfg/DFGClobberize.h:
(JSC::DFG::clobberize):
* dfg/DFGDCEPhase.cpp:
(JSC::DFG::DCEPhase::cleanVariables):
* dfg/DFGFixupPhase.cpp:
(JSC::DFG::FixupPhase::fixupNode):
* dfg/DFGGraph.h:
(JSC::DFG::Graph::clobbersWorld):
* dfg/DFGNodeType.h:
* dfg/DFGSpeculativeJIT.cpp:
(JSC::DFG::SpeculativeJIT::compileAdd):
* dfg/DFGSpeculativeJIT.h:
* dfg/DFGSpeculativeJIT32_64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* dfg/DFGSpeculativeJIT64.cpp:
(JSC::DFG::SpeculativeJIT::compile):
* ftl/FTLLowerDFGToLLVM.cpp:
(JSC::FTL::LowerDFGToLLVM::compileNode):
(JSC::FTL::LowerDFGToLLVM::compileValueAdd):



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@161218 268f45cc-cd09-0410-ab3c-d52691b4dbfc

Source/JavaScriptCore/dfg/DFGFixupPhase.cpp

diff --git a/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp b/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
index 03778c3..25eb9b5 100644
--- a/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
+++ b/Source/JavaScriptCore/dfg/DFGFixupPhase.cpp
@@ -154,11 +154,16 @@
         }
             
         case ValueAdd: {
-            if (attemptToMakeIntegerAdd(node))
+            if (attemptToMakeIntegerAdd(node)) {
+                node->setOp(ArithAdd);
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
+            }
             if (Node::shouldSpeculateNumberExpectingDefined(node->child1().node(), node->child2().node())) {
                 fixEdge<NumberUse>(node->child1());
                 fixEdge<NumberUse>(node->child2());
+                node->setOp(ArithAdd);
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             
@@ -326,17 +331,20 @@
             if (Node::shouldSpeculateInt32(node->child1().node(), node->child2().node())) {
                 fixEdge<Int32Use>(node->child1());
                 fixEdge<Int32Use>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (enableInt52()
                 && Node::shouldSpeculateMachineInt(node->child1().node(), node->child2().node())) {
                 fixEdge<MachineIntUse>(node->child1());
                 fixEdge<MachineIntUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (Node::shouldSpeculateNumber(node->child1().node(), node->child2().node())) {
                 fixEdge<NumberUse>(node->child1());
                 fixEdge<NumberUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (node->op() != CompareEq)
@@ -344,31 +352,37 @@
             if (Node::shouldSpeculateBoolean(node->child1().node(), node->child2().node())) {
                 fixEdge<BooleanUse>(node->child1());
                 fixEdge<BooleanUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (node->child1()->shouldSpeculateStringIdent() && node->child2()->shouldSpeculateStringIdent()) {
                 fixEdge<StringIdentUse>(node->child1());
                 fixEdge<StringIdentUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (node->child1()->shouldSpeculateString() && node->child2()->shouldSpeculateString() && GPRInfo::numberOfRegisters >= 7) {
                 fixEdge<StringUse>(node->child1());
                 fixEdge<StringUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (node->child1()->shouldSpeculateObject() && node->child2()->shouldSpeculateObject()) {
                 fixEdge<ObjectUse>(node->child1());
                 fixEdge<ObjectUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (node->child1()->shouldSpeculateObject() && node->child2()->shouldSpeculateObjectOrOther()) {
                 fixEdge<ObjectUse>(node->child1());
                 fixEdge<ObjectOrOtherUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             if (node->child1()->shouldSpeculateObjectOrOther() && node->child2()->shouldSpeculateObject()) {
                 fixEdge<ObjectOrOtherUse>(node->child1());
                 fixEdge<ObjectUse>(node->child2());
+                node->clearFlags(NodeMustGenerate | NodeClobbersWorld);
                 break;
             }
             break;