Changeset 227434 in webkit for trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp

Timestamp:

Jan 23, 2018, 12:39:34 PM (8 years ago)

Author:

[email protected]

Message:

Re-arrange TypedArray JSTypes to match the order of the TypedArrayType enum list.
​https://bugs.webkit.org/show_bug.cgi?id=181976
<rdar://problem/36766936>

Reviewed by Filip Pizlo.

1. The order of TypedArray JSTypes now matches the order the TypedArrayType enum list. I also added static asserts in TypedArrayType.h to enforce this.

Also redefined FOR_EACH_TYPED_ARRAY_TYPE() in terms of

2. Define 4 new values:
   1. FirstTypedArrayType
   2. LastTypedArrayType
   3. NumberOfTypedArrayTypesExcludingDataView
   4. NumberOfTypedArrayTypes

Use these everywhere where we iterate or bisect the TypedArray JSTypes.

3. Removed NUMBER_OF_TYPED_ARRAY_TYPES, and use NumberOfTypedArrayTypes instead.

4. Simplify the code that converts between TypedArrayType and JSType.

Changed typedArrayTypeForType() to be the mirror image of typeForTypedArrayType().
Previously, typedArrayTypeForType() converts DataViewType to NotTypedArray
instead of TypeDataView. Now, it converts to TypeDataView.

This does not result in any change of behavior because typedArrayTypeForType()
is only called in Structure::hasIndexingHeader(), and its result is passed to
isTypedView(), which handles TypeDataView correctly.

5. Also fixed a bug in SpeculativeJIT::compileGetTypedArrayByteOffset(). If the vector is null, we can skip the rest of the checks. While the current code does not result in incorrect behavior, it is inefficient, and communicates wrong information to the reader i.e. implying that there's something in the dataGPR when there's not. The dataGPR should also be null in this case.

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::handleConstantInternalFunction):

• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::compileIsTypedArrayView):
(JSC::DFG::SpeculativeJIT::compileGetTypedArrayByteOffset):

• ftl/FTLLowerDFGToB3.cpp:

(JSC::FTL::DFG::LowerDFGToB3::isTypedArrayView):

• ftl/FTLOSRExit.cpp:
• llint/LowLevelInterpreter.asm:
• llint/LowLevelInterpreter64.asm:
• runtime/JSGlobalObject.cpp:

(JSC::JSGlobalObject::visitChildren):

• runtime/JSType.h:
• runtime/TypedArrayType.cpp:

(JSC::typeForTypedArrayType): Deleted.

• runtime/TypedArrayType.h:

(JSC::typedArrayTypeForType):
(JSC::typeForTypedArrayType):

File:

• trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/runtime/JSGlobalObject.cpp

@@ -1421 +1421 @@
 #undef VISIT_LAZY_TYPE
 
-    for (unsigned i = NUMBER_OF_TYPED_ARRAY_TYPES; i--;)
+    for (unsigned i = NumberOfTypedArrayTypes; i--;)
         thisObject->lazyTypedArrayStructure(indexToTypedArrayType(i)).visit(visitor);