• benjamin@webkit.org's avatar
    Improve JSC use of Strings after the UString->String change · 762e2c65
    benjamin@webkit.org authored
    https://bugs.webkit.org/show_bug.cgi?id=95633
    
    Patch by Benjamin Poulain <bpoulain@apple.com> on 2012-09-04
    Reviewed by Geoffrey Garen.
    
    This patch improve the use of strings in the JSC runtime.
    
    The initialization of Identifier is left for future patches.
    
    The improvements are the following:
    -5% faster to raise one of the modified exception.
    -3 times faster to execute Boolean::toString()
    
    Most of the changes are just about using the new methods
    for string literals.
    
    With the changes, the binary on x86_64 gets 176 bytes smaller.
    
    * API/JSCallbackObjectFunctions.h:
    (JSC::::staticFunctionGetter):
    (JSC::::callbackGetter):
    * API/JSContextRef.cpp:
    (JSContextCreateBacktrace):
    * API/JSObjectRef.cpp:
    (JSObjectMakeFunctionWithCallback):
    * bytecode/CodeBlock.cpp:
    (JSC::valueToSourceString):
    (JSC::CodeBlock::nameForRegister):
    * interpreter/Interpreter.cpp:
    (JSC::Interpreter::addStackTraceIfNecessary):
    * runtime/ArrayConstructor.cpp:
    (JSC::constructArrayWithSizeQuirk):
    * runtime/ArrayPrototype.cpp:
    (JSC::shift):
    (JSC::unshift):
    (JSC::arrayProtoFuncPop):
    (JSC::arrayProtoFuncReverse):
    * runtime/BooleanPrototype.cpp:
    (JSC::booleanProtoFuncToString): Instead of instanciating new strings, reuse the
    keywords available in SmallStrings. Avoiding the creation of the JSString and StringImpl
    makes the method significantly faster.
    
    * runtime/DateConversion.cpp:
    (JSC::formatDateTime):
    * runtime/DatePrototype.cpp:
    (JSC::formatLocaleDate):
    (JSC::formateDateInstance):
    (JSC::dateProtoFuncToISOString):
    Change the way we use snprintf() for clarity and performance.
    
    Instead of allocating one extra byte to put a zero "just in case", we use the size returned
    by snprintf().
    To prevent any overflow from a programming mistake, we explicitely test for overflow and
    return an empty string.
    
    (JSC::dateProtoFuncToJSON):
    * runtime/Error.cpp:
    (JSC::createNotEnoughArgumentsError):
    (JSC::throwTypeError):
    (JSC::throwSyntaxError):
    * runtime/Error.h:
    (JSC::StrictModeTypeErrorFunction::create):
    * runtime/ErrorPrototype.cpp:
    (JSC::ErrorPrototype::finishCreation):
    (JSC::errorProtoFuncToString):
    Using a null String is correct because (8) uses jsString(), (9) tests for a length of 0.
    
    * runtime/ExceptionHelpers.cpp:
    (JSC::InterruptedExecutionError::defaultValue):
    (JSC::TerminatedExecutionError::defaultValue):
    (JSC::createStackOverflowError):
    (JSC::createOutOfMemoryError):
    * runtime/Executable.cpp:
    (JSC::EvalExecutable::compileInternal):
    (JSC::FunctionExecutable::paramString):
    * runtime/FunctionConstructor.cpp:
    (JSC::constructFunction):
    (JSC::constructFunctionSkippingEvalEnabledCheck):
    * runtime/FunctionPrototype.h:
    (JSC::FunctionPrototype::create):
    Using a null String for the name is correct because InternalFunction uses jsString()
    to create the name value.
    
    * runtime/InternalFunction.cpp:
    (JSC::InternalFunction::finishCreation):
    There is no need to create an empty string for a null string, jsString() handle both
    cases as empty JSString.
    
    * runtime/JSArray.cpp:
    (JSC::reject):
    (JSC::SparseArrayValueMap::put):
    (JSC::JSArray::put):
    (JSC::JSArray::putByIndexBeyondVectorLength):
    (JSC::JSArray::putDirectIndexBeyondVectorLength):
    (JSC::JSArray::setLength):
    (JSC::JSArray::pop):
    (JSC::JSArray::push):
    * runtime/JSFunction.cpp:
    (JSC::JSFunction::finishCreation): Same issue as InternalFunction::finishCreation.
    
    (JSC::JSFunction::callerGetter):
    (JSC::JSFunction::defineOwnProperty):
    * runtime/JSGlobalData.cpp:
    (JSC::enableAssembler): Use CFSTR() instead of CFStringCreateWithCString().
    CFStringCreateWithCString() copy the content and may choose to decode the data.
    CFSTR() is much more efficient.
    
    * runtime/JSGlobalObject.cpp:
    (JSC::JSGlobalObject::reset):
    JSFunction uses jsString() to create the name, we can use null strings instead
    of creating empty strings.
    
    (JSC::JSGlobalObject::createThrowTypeError): ditto.
    * runtime/JSGlobalObjectFunctions.cpp:
    (JSC::encode):
    (JSC::decode):
    (JSC::globalFuncEval):
    * runtime/JSONObject.cpp:
    (JSC::Stringifier::appendStringifiedValue):
    (JSC::Stringifier::Holder::appendNextProperty):
    (JSC::JSONProtoFuncParse):
    (JSC::JSONProtoFuncStringify):
    * runtime/JSObject.cpp:
    (JSC::JSObject::put):
    (JSC::JSObject::defaultValue):
    (JSC::JSObject::hasInstance):
    (JSC::JSObject::defineOwnProperty):
    * runtime/JSString.cpp:
    Return an empty JSString to avoid the creation of a temporary empty String.
    
    (JSC::JSRopeString::getIndexSlowCase):
    * runtime/JSString.h:
    (JSC): Remove the versions of jsNontrivialString() taking a char*. All the callers
    have been replaced by calls using ASCIILiteral.
    
    * runtime/JSValue.cpp:
    (JSC::JSValue::putToPrimitive):
    * runtime/LiteralParser.cpp:
    (JSC::::Lexer::lex):
    (JSC::::Lexer::lexString):
    (JSC::::Lexer::lexNumber):
    (JSC::::parse):
    * runtime/LiteralParser.h:
    (JSC::LiteralParser::getErrorMessage):
    * runtime/NumberPrototype.cpp:
    (JSC::numberProtoFuncToExponential):
    (JSC::numberProtoFuncToFixed):
    (JSC::numberProtoFuncToPrecision):
    (JSC::numberProtoFuncToString):
    * runtime/ObjectConstructor.cpp:
    (JSC::objectConstructorGetPrototypeOf):
    (JSC::objectConstructorGetOwnPropertyDescriptor):
    (JSC::objectConstructorGetOwnPropertyNames):
    (JSC::objectConstructorKeys):
    (JSC::toPropertyDescriptor):
    (JSC::objectConstructorDefineProperty):
    (JSC::objectConstructorDefineProperties):
    (JSC::objectConstructorCreate):
    (JSC::objectConstructorSeal):
    (JSC::objectConstructorFreeze):
    (JSC::objectConstructorPreventExtensions):
    (JSC::objectConstructorIsSealed):
    (JSC::objectConstructorIsFrozen):
    (JSC::objectConstructorIsExtensible):
    * runtime/ObjectPrototype.cpp:
    (JSC::objectProtoFuncDefineGetter):
    (JSC::objectProtoFuncDefineSetter):
    (JSC::objectProtoFuncToString):
    * runtime/RegExpConstructor.cpp:
    (JSC::constructRegExp):
    * runtime/RegExpObject.cpp:
    (JSC::reject):
    (JSC::regExpObjectSource):
    * runtime/RegExpPrototype.cpp:
    (JSC::regExpProtoFuncCompile):
    * runtime/StringObject.cpp:
    (JSC::StringObject::defineOwnProperty):
    * runtime/StringPrototype.cpp:
    (JSC::jsSpliceSubstrings):
    (JSC::jsSpliceSubstringsWithSeparators):
    
    
    git-svn-id: http://svn.webkit.org/repository/webkit/trunk@127505 268f45cc-cd09-0410-ab3c-d52691b4dbfc
    762e2c65