Diff
Modified: trunk/LayoutTests/ChangeLog (98198 => 98199)
--- trunk/LayoutTests/ChangeLog 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/LayoutTests/ChangeLog 2011-10-23 07:21:19 UTC (rev 98199)
@@ -1,3 +1,27 @@
+2011-10-21 Geoffrey Garen <[email protected]>
+
+ Separated string lifetime bits from character buffer state bits
+ https://bugs.webkit.org/show_bug.cgi?id=70673
+
+ Reviewed by Anders Carlsson.
+
+ These tests depended on non-deterministic effects of hash order, so I
+ had to update them:
+
+ * fast/dom/prototype-inheritance-2-expected.txt: Updated for slightly
+ different order of discovering properties.
+
+ * fast/js/delete-syntax-expected.txt:
+ * fast/js/script-tests/delete-syntax.js: Updated not to depend on iteration
+ order, since that's not what this test is about.
+
+ * http/tests/inspector/inspector-test.js: Updated not to depend on
+ global function iteration order. This test setup is pretty spaghetti.
+ I think I avoided making it even more spaghetti.
+
+ * inspector/storage-panel-dom-storage-expected.txt: Updated for changed
+ iteration order.
+
2011-10-22 Benjamin Poulain <[email protected]>
Make relayout-nested-positioned-elements-crash.html more reliable
Modified: trunk/LayoutTests/fast/dom/prototype-inheritance-2-expected.txt (98198 => 98199)
--- trunk/LayoutTests/fast/dom/prototype-inheritance-2-expected.txt 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/LayoutTests/fast/dom/prototype-inheritance-2-expected.txt 2011-10-23 07:21:19 UTC (rev 98199)
@@ -168,26 +168,26 @@
PASS MediaListPrototype from inner.document.forms.testForm.0.ownerDocument.styleSheets.0.media.__proto__
PASS MemoryInfo from inner.document.forms.testForm.0.ownerDocument.defaultView.console.memory
PASS MemoryInfoPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.console.memory.__proto__
-PASS MimeType from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.0
-PASS MimeTypeArray from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes
-PASS MimeTypeArrayConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.constructor
-PASS MimeTypeArrayPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.__proto__
-PASS MimeTypeConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.0.constructor
-PASS MimeTypePrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.0.__proto__
+PASS MimeType from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.mimeTypes.0
+PASS MimeTypeArray from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.mimeTypes
+PASS MimeTypeArrayConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.mimeTypes.constructor
+PASS MimeTypeArrayPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.mimeTypes.__proto__
+PASS MimeTypeConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.mimeTypes.0.constructor
+PASS MimeTypePrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.mimeTypes.0.__proto__
PASS NamedNodeMap from inner.document.forms.testForm.0.parentNode.attributes
-PASS Navigator from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation
-PASS NavigatorPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.__proto__
+PASS Navigator from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator
+PASS NavigatorPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.__proto__
PASS NodeList from inner.document.forms.testForm
PASS NodeListConstructor from inner.document.forms.testForm.constructor
PASS NodeListPrototype from inner.document.forms.testForm.__proto__
-PASS NodePrototype from inner.document.forms.testForm.0.attributes.0.__proto__.__proto__
+PASS NodePrototype from inner.document.forms.testForm.0.ownerDocument.__proto__.__proto__.__proto__
PASS Object from inner.document.location.__proto__.__proto__
-PASS Plugin from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.0.enabledPlugin
-PASS PluginArray from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.plugins
-PASS PluginArrayConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.plugins.constructor
-PASS PluginArrayPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.plugins.__proto__
-PASS PluginConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.plugins.0.constructor
-PASS PluginPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.clientInformation.mimeTypes.0.enabledPlugin.__proto__
+PASS Plugin from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.plugins.5
+PASS PluginArray from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.plugins
+PASS PluginArrayConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.plugins.constructor
+PASS PluginArrayPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.plugins.__proto__
+PASS PluginConstructor from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.plugins.0.constructor
+PASS PluginPrototype from inner.document.forms.testForm.0.ownerDocument.defaultView.navigator.plugins.5.__proto__
PASS RGBColor from inner.getComputedStyle(inner.document.body).getPropertyCSSValue(fill).rgbColor
PASS RGBColorConstructor from inner.getComputedStyle(inner.document.body).getPropertyCSSValue(fill).rgbColor.constructor
PASS RGBColorPrototype from inner.getComputedStyle(inner.document.body).getPropertyCSSValue(fill).rgbColor.__proto__
@@ -213,9 +213,9 @@
PASS Text from inner.document.forms.testForm.0.parentNode.lastElementChild.previousElementSibling.firstChild
PASS TextConstructor from inner.document.forms.testForm.0.attributes.0.lastChild.constructor
PASS TextPrototype from inner.document.forms.testForm.0.attributes.0.lastChild.__proto__
-PASS TimeRanges from inner.document.forms.testForm.0.previousElementSibling.played
-PASS TimeRangesConstructor from inner.document.forms.testForm.0.previousElementSibling.played.constructor
-PASS TimeRangesPrototype from inner.document.forms.testForm.0.previousElementSibling.played.__proto__
+PASS TimeRanges from inner.document.forms.testForm.0.previousElementSibling.seekable
+PASS TimeRangesConstructor from inner.document.forms.testForm.0.previousElementSibling.seekable.constructor
+PASS TimeRangesPrototype from inner.document.forms.testForm.0.previousElementSibling.seekable.__proto__
PASS ValidityState from inner.document.forms.testForm.0.0.validity
PASS ValidityStatePrototype from inner.document.forms.testForm.0.0.validity.__proto__
PASS WebKitCSSKeyframeRule from inner.document.getElementById("dummyStyle").sheet.cssRules.6.0
@@ -225,6 +225,8 @@
PASS WebKitCSSKeyframesRuleConstructor from inner.document.getElementById("dummyStyle").sheet.cssRules.6.constructor
PASS WebKitCSSKeyframesRulePrototype from inner.document.getElementById("dummyStyle").sheet.cssRules.6.__proto__
Never found Audio
+Never found AudioContext
+Never found AudioPannerNode
Never found Blob
Never found CDATASection
Never found CSSRule
@@ -438,6 +440,7 @@
Never found SharedWorker
Never found StyleSheet
Never found TextMetrics
+Never found WebKitCSSFilterValue
Never found WebKitCSSMatrix
Never found WebKitCSSTransformValue
Never found WebKitPoint
Modified: trunk/LayoutTests/fast/js/delete-syntax-expected.txt (98198 => 98199)
--- trunk/LayoutTests/fast/js/delete-syntax-expected.txt 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/LayoutTests/fast/js/delete-syntax-expected.txt 2011-10-23 07:21:19 UTC (rev 98199)
@@ -29,7 +29,7 @@
PASS RegExp.prototype.compile is regExpPrototypeCompile
PASS RegExp.prototype.exec is undefined
PASS RegExp.prototype.test is null
-PASS String(Object.getOwnPropertyNames(Object.prototype)) is "constructor,valueOf,__lookupGetter__,toLocaleString,__defineGetter__,hasOwnProperty,propertyIsEnumerable,toString,__lookupSetter__,isPrototypeOf"
+PASS Object.getOwnPropertyNames(Object.prototype).indexOf('__defineSetter__') is -1
PASS successfullyParsed is true
TEST COMPLETE
Modified: trunk/LayoutTests/fast/js/script-tests/delete-syntax.js (98198 => 98199)
--- trunk/LayoutTests/fast/js/script-tests/delete-syntax.js 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/LayoutTests/fast/js/script-tests/delete-syntax.js 2011-10-23 07:21:19 UTC (rev 98199)
@@ -70,7 +70,7 @@
// Check that once a property is deleted its name is removed from the property name array.
delete Object.prototype.__defineSetter__;
-shouldBe("String(Object.getOwnPropertyNames(Object.prototype))", '"constructor,valueOf,__lookupGetter__,toLocaleString,__defineGetter__,hasOwnProperty,propertyIsEnumerable,toString,__lookupSetter__,isPrototypeOf"');
+shouldBe("Object.getOwnPropertyNames(Object.prototype).indexOf('__defineSetter__')", "-1");
var successfullyParsed = true;
Modified: trunk/LayoutTests/http/tests/inspector/inspector-test.js (98198 => 98199)
--- trunk/LayoutTests/http/tests/inspector/inspector-test.js 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/LayoutTests/http/tests/inspector/inspector-test.js 2011-10-23 07:21:19 UTC (rev 98199)
@@ -438,9 +438,9 @@
}
}
- var initializationFunctions = [];
+ var initializationFunctions = [ String(initialize_InspectorTest) ];
for (var name in window) {
- if (name.indexOf("initialize_") === 0 && typeof window[name] === "function")
+ if (name.indexOf("initialize_") === 0 && typeof window[name] === "function" && name !== "initialize_InspectorTest")
initializationFunctions.push(window[name].toString());
}
var parameters = ["[" + initializationFunctions + "]", test, completeTestCallId];
Modified: trunk/LayoutTests/inspector/storage-panel-dom-storage-expected.txt (98198 => 98199)
--- trunk/LayoutTests/inspector/storage-panel-dom-storage-expected.txt 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/LayoutTests/inspector/storage-panel-dom-storage-expected.txt 2011-10-23 07:21:19 UTC (rev 98199)
@@ -4,8 +4,8 @@
Did show: Local storage
Did show: Session storage
Local storage content:
-KeyValuea0=value0, a6=value6, a8=value8, a4=value4, a2=value2, a1=value1, resource-history{}a9=value9, a3=value3, a7=value7, a5=value5,
+KeyValueresource-history{}a4=value4, a0=value0, a2=value2, a7=value7, a9=value9, a5=value5, a8=value8, a1=value1, a3=value3, a6=value6,
Session storage content:
-KeyValueb5=value15, b4=value14, b3=value13, b6=value16, b7=value17, b0=value10, b9=value19, b8=value18, b2=value12, b1=value11,
+KeyValueb4=value14, b3=value13, b0=value10, b9=value19, b5=value15, b6=value16, b7=value17, b8=value18, b1=value11, b2=value12,
DONE
Modified: trunk/Source/_javascript_Core/ChangeLog (98198 => 98199)
--- trunk/Source/_javascript_Core/ChangeLog 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/_javascript_Core/ChangeLog 2011-10-23 07:21:19 UTC (rev 98199)
@@ -1,3 +1,52 @@
+2011-10-21 Geoffrey Garen <[email protected]>
+
+ Separated string lifetime bits from character buffer state bits
+ https://bugs.webkit.org/show_bug.cgi?id=70673
+
+ Reviewed by Anders Carlsson.
+
+ Moved the static/immortal bit into the bottom bit of the refcount, and
+ moved all other bits into the high bits of the hash code.
+
+ This is the first step toward a new Characters/PassString class, and it
+ makes ref/deref slightly more efficient.
+
+ * create_hash_table:
+ * wtf/StringHasher.h:
+ (WTF::StringHasher::hash): Tweaked the string hashing function to leave
+ the top bits clear, so they can be used as flags.
+
+ Fixed some small differences between the PERL copy of this function and
+ the C++ copy of this function, which could have in theory caused subtle
+ crashes.
+
+ * wtf/text/StringImpl.cpp:
+ (WTF::StringImpl::sharedBuffer):
+ (WTF::StringImpl::createWithTerminatingNullCharacter):
+ * wtf/text/StringImpl.h:
+ (WTF::StringImpl::StringImpl):
+ (WTF::StringImpl::cost): Renamed s_refCountFlagShouldReportedCost to
+ s_didReportExtraCost, since the original name was both self-contradictory
+ and used as a double-negative.
+
+ (WTF::StringImpl::isIdentifier):
+ (WTF::StringImpl::setIsIdentifier):
+ (WTF::StringImpl::hasTerminatingNullCharacter):
+ (WTF::StringImpl::isAtomic):
+ (WTF::StringImpl::setIsAtomic):
+ (WTF::StringImpl::setHash):
+ (WTF::StringImpl::rawHash):
+ (WTF::StringImpl::hasHash):
+ (WTF::StringImpl::existingHash):
+ (WTF::StringImpl::hash):
+ (WTF::StringImpl::hasOneRef):
+ (WTF::StringImpl::ref):
+ (WTF::StringImpl::deref):
+ (WTF::StringImpl::bufferOwnership):
+ (WTF::StringImpl::isStatic): Moved the static/immortal bit into the bottom
+ bit of the refcount. Now, all lifetime information lives in the refcount
+ field. Moved the other bits into the hash code field.
+
2011-10-21 Filip Pizlo <[email protected]>
DFG inlining sometimes fails to reset constant references
Modified: trunk/Source/_javascript_Core/create_hash_table (98198 => 98199)
--- trunk/Source/_javascript_Core/create_hash_table 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/_javascript_Core/create_hash_table 2011-10-23 07:21:19 UTC (rev 98199)
@@ -179,7 +179,6 @@
# Paul Hsieh's SuperFastHash
# http://www.azillionmonkeys.com/qed/hash.html
-# Ported from UString..
sub hashValue($) {
my @chars = split(/ */, $_[0]);
@@ -207,7 +206,7 @@
}
# Handle end case
- if ($rem !=0) {
+ if ($rem != 0) {
$hash += ord($chars[$s]);
$hash ^= (leftShift($hash, 11)% $EXP2_32);
$hash += $hash >> 17;
@@ -221,12 +220,16 @@
$hash += ($hash >> 15);
$hash = $hash% $EXP2_32;
$hash ^= (leftShift($hash, 10)% $EXP2_32);
-
- # this avoids ever returning a hash code of 0, since that is used to
- # signal "hash not computed yet", using a value that is likely to be
- # effectively the same as 0 when the low bits are masked
- $hash = 0x80000000 if ($hash == 0);
+ # Save 6 bits for StringImpl to use as flags.
+ $hash = ($hash >> 6);
+
+ # This avoids ever returning a hash code of 0, since that is used to
+ # signal "hash not computed yet". Setting the high bit maintains
+ # reasonable fidelity to a hash code of 0 because it is likely to yield
+ # exactly 0 when hash lookup masks out the high bits.
+ $hash = (0x80000000 >> 6) if ($hash == 0);
+
return $hash;
}
Modified: trunk/Source/_javascript_Core/wtf/StringHasher.h (98198 => 98199)
--- trunk/Source/_javascript_Core/wtf/StringHasher.h 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/_javascript_Core/wtf/StringHasher.h 2011-10-23 07:21:19 UTC (rev 98199)
@@ -31,8 +31,13 @@
// Paul Hsieh's SuperFastHash
// http://www.azillionmonkeys.com/qed/hash.html
// char* data is interpreted as latin-encoded (zero extended to 16 bits).
+
+// NOTE: This class must stay in sync with the create_hash_table script in
+// _javascript_Core and the CodeGeneratorJS.pm script in WebCore.
class StringHasher {
public:
+ static const unsigned flagCount = 6; // Save 6 bits for StringImpl to use as flags.
+
inline StringHasher()
: m_hash(stringHashingStartValue)
, m_hasPendingCharacter(false)
@@ -76,14 +81,16 @@
result += result >> 15;
result ^= result << 10;
- // First bit is used in UStringImpl for m_isIdentifier.
- result &= 0x7fffffff;
+ // Reserving the high bits for flags perserves most of the hash's value,
+ // since hash lookup typically masks out the high bits anyway.
+ result >>= flagCount;
// This avoids ever returning a hash code of 0, since that is used to
- // signal "hash not computed yet", using a value that is likely to be
- // effectively the same as 0 when the low bits are masked.
+ // signal "hash not computed yet". Setting the high bit maintains
+ // reasonable fidelity to a hash code of 0 because it is likely to yield
+ // exactly 0 when hash lookup masks out the high bits.
if (!result)
- return 0x40000000;
+ result = 0x80000000 >> flagCount;
return result;
}
Modified: trunk/Source/_javascript_Core/wtf/text/StringImpl.cpp (98198 => 98199)
--- trunk/Source/_javascript_Core/wtf/text/StringImpl.cpp 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/_javascript_Core/wtf/text/StringImpl.cpp 2011-10-23 07:21:19 UTC (rev 98199)
@@ -168,7 +168,7 @@
if (ownership == BufferOwned) {
ASSERT(!m_sharedBuffer);
m_sharedBuffer = SharedUChar::create(new SharableUChar(m_data)).leakRef();
- m_refCountAndFlags = (m_refCountAndFlags & ~s_refCountMaskBufferOwnership) | BufferShared;
+ m_hashAndFlags = (m_hashAndFlags & ~s_hashMaskBufferOwnership) | BufferShared;
}
ASSERT(bufferOwnership() == BufferShared);
@@ -1156,8 +1156,7 @@
memcpy(data, string.m_data, length * sizeof(UChar));
data[length] = 0;
terminatedString->m_length--;
- terminatedString->m_hash = string.m_hash;
- terminatedString->m_refCountAndFlags |= s_refCountFlagHasTerminatingNullCharacter;
+ terminatedString->m_hashAndFlags = (string.m_hashAndFlags & ~s_flagMask) | s_hashFlagHasTerminatingNullCharacter;
return terminatedString.release();
}
Modified: trunk/Source/_javascript_Core/wtf/text/StringImpl.h (98198 => 98199)
--- trunk/Source/_javascript_Core/wtf/text/StringImpl.h 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/_javascript_Core/wtf/text/StringImpl.h 2011-10-23 07:21:19 UTC (rev 98199)
@@ -83,13 +83,13 @@
// Used to construct static strings, which have an special refCount that can never hit zero.
// This means that the static string will never be destroyed, which is important because
// static strings will be shared across threads & ref-counted in a non-threadsafe manner.
- enum StaticStringConstructType { ConstructStaticString };
- StringImpl(const UChar* characters, unsigned length, StaticStringConstructType)
- : m_refCountAndFlags(s_refCountFlagStatic | s_refCountFlagIsIdentifier | BufferOwned)
+ enum ConstructStaticStringTag { ConstructStaticString };
+ StringImpl(const UChar* characters, unsigned length, ConstructStaticStringTag)
+ : m_refCount(s_refCountFlagIsStaticString)
, m_length(length)
, m_data(characters)
, m_buffer(0)
- , m_hash(0)
+ , m_hashAndFlags(s_hashFlagIsIdentifier | BufferOwned)
{
// Ensure that the hash is computed so that AtomicStringHash can call existingHash()
// with impunity. The empty string is special because it is never entered into
@@ -99,11 +99,11 @@
// Create a normal string with internal storage (BufferInternal)
StringImpl(unsigned length)
- : m_refCountAndFlags(s_refCountIncrement | s_refCountFlagShouldReportedCost | BufferInternal)
+ : m_refCount(s_refCountIncrement)
, m_length(length)
, m_data(reinterpret_cast<const UChar*>(this + 1))
, m_buffer(0)
- , m_hash(0)
+ , m_hashAndFlags(BufferInternal)
{
ASSERT(m_data);
ASSERT(m_length);
@@ -111,11 +111,11 @@
// Create a StringImpl adopting ownership of the provided buffer (BufferOwned)
StringImpl(const UChar* characters, unsigned length)
- : m_refCountAndFlags(s_refCountIncrement | s_refCountFlagShouldReportedCost | BufferOwned)
+ : m_refCount(s_refCountIncrement)
, m_length(length)
, m_data(characters)
, m_buffer(0)
- , m_hash(0)
+ , m_hashAndFlags(BufferOwned)
{
ASSERT(m_data);
ASSERT(m_length);
@@ -123,11 +123,11 @@
// Used to create new strings that are a substring of an existing StringImpl (BufferSubstring)
StringImpl(const UChar* characters, unsigned length, PassRefPtr<StringImpl> base)
- : m_refCountAndFlags(s_refCountIncrement | s_refCountFlagShouldReportedCost | BufferSubstring)
+ : m_refCount(s_refCountIncrement)
, m_length(length)
, m_data(characters)
, m_substringBuffer(base.leakRef())
- , m_hash(0)
+ , m_hashAndFlags(BufferSubstring)
{
ASSERT(m_data);
ASSERT(m_length);
@@ -136,25 +136,16 @@
// Used to construct new strings sharing an existing SharedUChar (BufferShared)
StringImpl(const UChar* characters, unsigned length, PassRefPtr<SharedUChar> sharedBuffer)
- : m_refCountAndFlags(s_refCountIncrement | s_refCountFlagShouldReportedCost | BufferShared)
+ : m_refCount(s_refCountIncrement)
, m_length(length)
, m_data(characters)
, m_sharedBuffer(sharedBuffer.leakRef())
- , m_hash(0)
+ , m_hashAndFlags(BufferShared)
{
ASSERT(m_data);
ASSERT(m_length);
}
- // For use only by AtomicString's XXXTranslator helpers.
- void setHash(unsigned hash)
- {
- ASSERT(!isStatic());
- ASSERT(!m_hash);
- ASSERT(hash == StringHasher::computeHash(m_data, m_length));
- m_hash = hash;
- }
-
public:
~StringImpl();
@@ -217,7 +208,6 @@
}
static PassRefPtr<StringImpl> adopt(StringBuffer&);
- void ref() { m_refCountAndFlags += s_refCountIncrement; }
unsigned length() const { return m_length; }
SharedUChar* sharedBuffer();
const UChar* characters() const { return m_data; }
@@ -228,42 +218,96 @@
if (bufferOwnership() == BufferSubstring)
return m_substringBuffer->cost();
- if (m_refCountAndFlags & s_refCountFlagShouldReportedCost) {
- m_refCountAndFlags &= ~s_refCountFlagShouldReportedCost;
- return m_length;
- }
- return 0;
+ if (m_hashAndFlags & s_hashFlagDidReportCost)
+ return 0;
+
+ m_hashAndFlags |= s_hashFlagDidReportCost;
+ return m_length;
}
- bool isIdentifier() const { return m_refCountAndFlags & s_refCountFlagIsIdentifier; }
+ bool isIdentifier() const { return m_hashAndFlags & s_hashFlagIsIdentifier; }
void setIsIdentifier(bool isIdentifier)
{
ASSERT(!isStatic());
if (isIdentifier)
- m_refCountAndFlags |= s_refCountFlagIsIdentifier;
+ m_hashAndFlags |= s_hashFlagIsIdentifier;
else
- m_refCountAndFlags &= ~s_refCountFlagIsIdentifier;
+ m_hashAndFlags &= ~s_hashFlagIsIdentifier;
}
- bool hasTerminatingNullCharacter() const { return m_refCountAndFlags & s_refCountFlagHasTerminatingNullCharacter; }
+ bool hasTerminatingNullCharacter() const { return m_hashAndFlags & s_hashFlagHasTerminatingNullCharacter; }
- bool isAtomic() const { return m_refCountAndFlags & s_refCountFlagIsAtomic; }
+ bool isAtomic() const { return m_hashAndFlags & s_hashFlagIsAtomic; }
void setIsAtomic(bool isIdentifier)
{
ASSERT(!isStatic());
if (isIdentifier)
- m_refCountAndFlags |= s_refCountFlagIsAtomic;
+ m_hashAndFlags |= s_hashFlagIsAtomic;
else
- m_refCountAndFlags &= ~s_refCountFlagIsAtomic;
+ m_hashAndFlags &= ~s_hashFlagIsAtomic;
}
- unsigned hash() const { if (!m_hash) m_hash = StringHasher::computeHash(m_data, m_length); return m_hash; }
- unsigned existingHash() const { ASSERT(m_hash); return m_hash; }
- bool hasHash() const { return m_hash; }
+private:
+ // The high bits of 'hash' are always empty, but we prefer to store our flags
+ // in the low bits because it makes them slightly more efficient to access.
+ // So, we shift left and right when setting and getting our hash code.
+ void setHash(unsigned hash) const
+ {
+ ASSERT(!hasHash());
+ ASSERT(hash == StringHasher::computeHash(m_data, m_length)); // Multiple clients assume that StringHasher is the canonical string hash function.
+ ASSERT(!(hash & (s_flagMask << (8 * sizeof(hash) - s_flagCount)))); // Verify that enough high bits are empty.
+
+ hash <<= s_flagCount;
+ ASSERT(!(hash & m_hashAndFlags)); // Verify that enough low bits are empty after shift.
+ ASSERT(hash); // Verify that 0 is a valid sentinel hash value.
- ALWAYS_INLINE void deref() { m_refCountAndFlags -= s_refCountIncrement; if (!(m_refCountAndFlags & (s_refCountMask | s_refCountFlagStatic))) delete this; }
- ALWAYS_INLINE bool hasOneRef() const { return (m_refCountAndFlags & (s_refCountMask | s_refCountFlagStatic)) == s_refCountIncrement; }
+ m_hashAndFlags |= hash; // Store hash with flags in low bits.
+ }
+ unsigned rawHash() const
+ {
+ return m_hashAndFlags >> s_flagCount;
+ }
+
+public:
+ bool hasHash() const
+ {
+ return rawHash() != 0;
+ }
+
+ unsigned existingHash() const
+ {
+ ASSERT(hasHash());
+ return rawHash();
+ }
+
+ unsigned hash() const
+ {
+ if (!hasHash())
+ setHash(StringHasher::computeHash(m_data, m_length));
+ return existingHash();
+ }
+
+ inline bool hasOneRef() const
+ {
+ return m_refCount == s_refCountIncrement;
+ }
+
+ inline void ref()
+ {
+ m_refCount += s_refCountIncrement;
+ }
+
+ inline void deref()
+ {
+ if (m_refCount == s_refCountIncrement) {
+ delete this;
+ return;
+ }
+
+ m_refCount -= s_refCountIncrement;
+ }
+
static StringImpl* empty();
static void copyChars(UChar* destination, const UChar* source, unsigned numCharacters)
@@ -351,24 +395,27 @@
static PassRefPtr<StringImpl> createStrippingNullCharactersSlowCase(const UChar*, unsigned length);
- BufferOwnership bufferOwnership() const { return static_cast<BufferOwnership>(m_refCountAndFlags & s_refCountMaskBufferOwnership); }
- bool isStatic() const { return m_refCountAndFlags & s_refCountFlagStatic; }
+ BufferOwnership bufferOwnership() const { return static_cast<BufferOwnership>(m_hashAndFlags & s_hashMaskBufferOwnership); }
+ bool isStatic() const { return m_refCount & s_refCountFlagIsStaticString; }
template <class UCharPredicate> PassRefPtr<StringImpl> stripMatchedCharacters(UCharPredicate);
template <class UCharPredicate> PassRefPtr<StringImpl> simplifyMatchedCharactersToSpace(UCharPredicate);
- // The bottom 7 bits hold flags, the top 25 bits hold the ref count.
- // When dereferencing StringImpls we check for the ref count AND the
- // static bit both being zero - static strings are never deleted.
- static const unsigned s_refCountMask = 0xFFFFFF80;
- static const unsigned s_refCountIncrement = 0x80;
- static const unsigned s_refCountFlagStatic = 0x40;
- static const unsigned s_refCountFlagHasTerminatingNullCharacter = 0x20;
- static const unsigned s_refCountFlagIsAtomic = 0x10;
- static const unsigned s_refCountFlagShouldReportedCost = 0x8;
- static const unsigned s_refCountFlagIsIdentifier = 0x4;
- static const unsigned s_refCountMaskBufferOwnership = 0x3;
+ // The bottom bit in the ref count indicates a static (immortal) string.
+ static const unsigned s_refCountFlagIsStaticString = 0x1;
+ static const unsigned s_refCountIncrement = 0x2; // This allows us to ref / deref without disturbing the static string flag.
- unsigned m_refCountAndFlags;
+ // The bottom 6 bits in the hash are flags.
+ static const unsigned s_flagCount = 6;
+ static const unsigned s_flagMask = (1u << s_flagCount) - 1;
+ COMPILE_ASSERT(s_flagCount == StringHasher::flagCount, StringHasher_reserves_enough_bits_for_StringImpl_flags);
+
+ static const unsigned s_hashFlagHasTerminatingNullCharacter = 1u << 5;
+ static const unsigned s_hashFlagIsAtomic = 1u << 4;
+ static const unsigned s_hashFlagDidReportCost = 1u << 3;
+ static const unsigned s_hashFlagIsIdentifier = 1u << 2;
+ static const unsigned s_hashMaskBufferOwnership = 1u | (1u << 1);
+
+ unsigned m_refCount;
unsigned m_length;
const UChar* m_data;
union {
@@ -376,7 +423,7 @@
StringImpl* m_substringBuffer;
SharedUChar* m_sharedBuffer;
};
- mutable unsigned m_hash;
+ mutable unsigned m_hashAndFlags;
};
bool equal(const StringImpl*, const StringImpl*);
Modified: trunk/Source/WebCore/ChangeLog (98198 => 98199)
--- trunk/Source/WebCore/ChangeLog 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/WebCore/ChangeLog 2011-10-23 07:21:19 UTC (rev 98199)
@@ -1,3 +1,13 @@
+2011-10-22 Geoffrey Garen <[email protected]>
+
+ Separated string lifetime bits from character buffer state bits
+ https://bugs.webkit.org/show_bug.cgi?id=70673
+
+ Reviewed by Anders Carlsson.
+
+ * bindings/scripts/CodeGeneratorJS.pm:
+ (GenerateHashValue): Updated for string hashing changes in _javascript_Core.
+
2011-10-22 Pratik Solanki <[email protected]>
HTTPBodyStream in NSURLRequest gets lost when using CFNetwork loader
Modified: trunk/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm (98198 => 98199)
--- trunk/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm 2011-10-23 05:03:19 UTC (rev 98198)
+++ trunk/Source/WebCore/bindings/scripts/CodeGeneratorJS.pm 2011-10-23 07:21:19 UTC (rev 98199)
@@ -3038,7 +3038,8 @@
push(@implContent, "static JSC_CONST_HASHTABLE HashTable $name = { $compactSize, $compactSizeMask, $nameEntries, 0 };\n");
}
-# Internal helper
+# Paul Hsieh's SuperFastHash
+# http://www.azillionmonkeys.com/qed/hash.html
sub GenerateHashValue
{
my $object = shift;
@@ -3048,16 +3049,16 @@
# This hash is designed to work on 16-bit chunks at a time. But since the normal case
# (above) is to hash UTF-16 characters, we just treat the 8-bit chars as if they
# were 16-bit chunks, which should give matching results
-
+
my $EXP2_32 = 4294967296;
-
+
my $hash = 0x9e3779b9;
my $l = scalar @chars; #I wish this was in Ruby --- Maks
my $rem = $l & 1;
$l = $l >> 1;
-
+
my $s = 0;
-
+
# Main loop
for (; $l > 0; $l--) {
$hash += ord($chars[$s]);
@@ -3067,14 +3068,14 @@
$hash += $hash >> 11;
$hash %= $EXP2_32;
}
-
+
# Handle end case
if ($rem != 0) {
$hash += ord($chars[$s]);
$hash ^= (leftShift($hash, 11)% $EXP2_32);
$hash += $hash >> 17;
}
-
+
# Force "avalanching" of final 127 bits
$hash ^= leftShift($hash, 3);
$hash += ($hash >> 5);
@@ -3083,12 +3084,16 @@
$hash += ($hash >> 15);
$hash = $hash% $EXP2_32;
$hash ^= (leftShift($hash, 10)% $EXP2_32);
-
- # this avoids ever returning a hash code of 0, since that is used to
- # signal "hash not computed yet", using a value that is likely to be
- # effectively the same as 0 when the low bits are masked
- $hash = 0x80000000 if ($hash == 0);
-
+
+ # Save 6 bits for StringImpl to use as flags.
+ $hash = ($hash >> 6);
+
+ # This avoids ever returning a hash code of 0, since that is used to
+ # signal "hash not computed yet". Setting the high bit maintains
+ # reasonable fidelity to a hash code of 0 because it is likely to yield
+ # exactly 0 when hash lookup masks out the high bits.
+ $hash = (0x80000000 >> 6) if ($hash == 0);
+
return $hash;
}
