Changeset 183548 in webkit for trunk/Source/JavaScriptCore/dfg/DFGAbstractValue.cpp

Timestamp:

Apr 29, 2015, 8:55:54 AM (10 years ago)

Author:

[email protected]

Message:

TypeOf should return SpecStringIdent and the DFG should know this
​https://bugs.webkit.org/show_bug.cgi?id=144376

Reviewed by Andreas Kling.

Make TypeOf return atomic strings. That's a simple change in SmallStrings.

Make the DFG know this and use it for optimization. This makes Switch(TypeOf) a bit less
bad.

• dfg/DFGAbstractInterpreterInlines.h:

(JSC::DFG::AbstractInterpreter<AbstractStateType>::executeEffects):

• dfg/DFGAbstractValue.cpp:

(JSC::DFG::AbstractValue::setType):

• dfg/DFGAbstractValue.h:

(JSC::DFG::AbstractValue::setType):

• dfg/DFGInPlaceAbstractState.cpp:

(JSC::DFG::InPlaceAbstractState::initialize):

• dfg/DFGPredictionPropagationPhase.cpp:

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

• runtime/SmallStrings.cpp:

(JSC::SmallStrings::initialize):

• tests/stress/switch-typeof-indirect.js: Added.

(bar):
(foo):
(test):

• tests/stress/switch-typeof-slightly-indirect.js: Added.

(foo):
(test):

• tests/stress/switch-typeof.js: Added.

(foo):
(test):

File:

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

trunk/Source/JavaScriptCore/dfg/DFGAbstractValue.cpp

@@ -119 +119 @@
 }
 
+void AbstractValue::setType(Graph& graph, SpeculatedType type)
+{
+    SpeculatedType cellType = type & SpecCell;
+    if (cellType) {
+        if (!(cellType & ~SpecString))
+            m_structure = graph.m_vm.stringStructure.get();
+        else
+            m_structure.makeTop();
+        m_arrayModes = ALL_ARRAY_MODES;
+    } else {
+        m_structure.clear();
+        m_arrayModes = 0;
+    }
+    m_type = type;
+    m_value = JSValue();
+    checkConsistency();
+}
+
 void AbstractValue::fixTypeForRepresentation(NodeFlags representation)
 {