Changeset 102442 in webkit for trunk/Source/JavaScriptCore/dfg/DFGByteCodeParser.cpp

Timestamp:

Dec 9, 2011, 12:45:46 AM (13 years ago)

Author:

[email protected]

Message:

Avoid reloading storage pointer for indexed properties unnecessarily
​https://bugs.webkit.org/show_bug.cgi?id=74136

Reviewed by Filip Pizlo.

Add a node to represent loading property storage for indexed properties.
This allows us to reduce code generated for sequential access of arrays,
strings, etc. This results in up to 5% improvement in code that is
very heavy on indexed reads, such as matrix operations in typed arrays
and 20% faster on microbenchmarks.

Currently this is only supported by GetByVal and other similar indexed reads.

• bytecode/PredictedType.h:

(JSC::isFixedIndexedStorageObjectPrediction):

• dfg/DFGAbstractState.cpp:

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

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::handleIntrinsic):
(JSC::DFG::ByteCodeParser::parseBlock):

• dfg/DFGNode.h:
• dfg/DFGPropagator.cpp:

(JSC::DFG::Propagator::propagateNodePredictions):
(JSC::DFG::Propagator::fixupNode):
(JSC::DFG::Propagator::getIndexedPropertyStorageLoadElimination):
(JSC::DFG::Propagator::performNodeCSE):

• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::compileGetCharCodeAt):
(JSC::DFG::SpeculativeJIT::compileGetByValOnString):
(JSC::DFG::SpeculativeJIT::compileGetByValOnByteArray):
(JSC::DFG::SpeculativeJIT::compileGetByValOnIntTypedArray):
(JSC::DFG::SpeculativeJIT::compileGetByValOnFloatTypedArray):
(JSC::DFG::SpeculativeJIT::compileGetIndexedPropertyStorage):

• dfg/DFGSpeculativeJIT.h:
• dfg/DFGSpeculativeJIT32_64.cpp:

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

• dfg/DFGSpeculativeJIT64.cpp:

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

File:

• trunk/Source/JavaScriptCore/dfg/DFGByteCodeParser.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/dfg/DFGByteCodeParser.cpp

@@ -1208 +1208 @@
         if (firstArg + 1 != lastArg)
             return false;
-
-        NodeIndex charCode = addToGraph(StringCharCodeAt, get(firstArg), getToInt32(firstArg + 1));
+        if (!(m_graph[get(firstArg)].prediction() & PredictString))
+            return false;
+        
+        NodeIndex storage = addToGraph(GetIndexedPropertyStorage, get(firstArg), getToInt32(firstArg + 1));
+        NodeIndex charCode = addToGraph(StringCharCodeAt, get(firstArg), getToInt32(firstArg + 1), storage);
         if (usesResult)
             set(resultOperand, charCode);
@@ -1218 +1221 @@
         if (firstArg + 1 != lastArg)
             return false;
-        
-        NodeIndex charCode = addToGraph(StringCharAt, get(firstArg), getToInt32(firstArg + 1));
+        if (!(m_graph[get(firstArg)].prediction() & PredictString))
+            return false;
+
+        NodeIndex storage = addToGraph(GetIndexedPropertyStorage, get(firstArg), getToInt32(firstArg + 1));
+        NodeIndex charCode = addToGraph(StringCharAt, get(firstArg), getToInt32(firstArg + 1), storage);
         if (usesResult)
             set(resultOperand, charCode);
@@ -1612 +1618 @@
             NodeIndex base = get(currentInstruction[2].u.operand);
             NodeIndex property = get(currentInstruction[3].u.operand);
-
-            NodeIndex getByVal = addToGraph(GetByVal, OpInfo(0), OpInfo(prediction), base, property);
+            NodeIndex propertyStorage = addToGraph(GetIndexedPropertyStorage, base, property);
+            NodeIndex getByVal = addToGraph(GetByVal, OpInfo(0), OpInfo(prediction), base, property, propertyStorage);
             set(currentInstruction[1].u.operand, getByVal);