Title: [197542] trunk/Source/_javascript_Core
- Revision
- 197542
- Author
- fpi...@apple.com
- Date
- 2016-03-03 18:43:53 -0800 (Thu, 03 Mar 2016)
Log Message
Octane/regexp's Exec function should benefit from array length accessor inlining
https://bugs.webkit.org/show_bug.cgi?id=154994
Reviewed by Benjamin Poulain.
It does:
var thingy = blahbitty.blah;
if (thingy)
foo = thingy.length;
So, 'thingy' is SpecArray | SpecOther, which prevents the array length accessor inlining from
kicking in. Our strategy for this elsewhere in the DFG is to allow a one-time speculation that
we won't see SpecOther, since *usually* we see SpecOther mixed with other stuff in cases like
this where there is some null check guarding the code.
This gives another slight speed-up on Octane/regexp.
* bytecode/SpeculatedType.h:
(JSC::isCellSpeculation):
(JSC::isCellOrOtherSpeculation):
(JSC::isNotCellSpeculation):
* dfg/DFGFixupPhase.cpp:
(JSC::DFG::FixupPhase::fixupNode):
* dfg/DFGNode.h:
(JSC::DFG::Node::shouldSpeculateCell):
(JSC::DFG::Node::shouldSpeculateCellOrOther):
(JSC::DFG::Node::shouldSpeculateNotCell):
Modified Paths
Diff
Modified: trunk/Source/_javascript_Core/ChangeLog (197541 => 197542)
--- trunk/Source/_javascript_Core/ChangeLog 2016-03-04 02:26:49 UTC (rev 197541)
+++ trunk/Source/_javascript_Core/ChangeLog 2016-03-04 02:43:53 UTC (rev 197542)
@@ -1,3 +1,34 @@
+2016-03-03 Filip Pizlo <fpi...@apple.com>
+
+ Octane/regexp's Exec function should benefit from array length accessor inlining
+ https://bugs.webkit.org/show_bug.cgi?id=154994
+
+ Reviewed by Benjamin Poulain.
+
+ It does:
+
+ var thingy = blahbitty.blah;
+ if (thingy)
+ foo = thingy.length;
+
+ So, 'thingy' is SpecArray | SpecOther, which prevents the array length accessor inlining from
+ kicking in. Our strategy for this elsewhere in the DFG is to allow a one-time speculation that
+ we won't see SpecOther, since *usually* we see SpecOther mixed with other stuff in cases like
+ this where there is some null check guarding the code.
+
+ This gives another slight speed-up on Octane/regexp.
+
+ * bytecode/SpeculatedType.h:
+ (JSC::isCellSpeculation):
+ (JSC::isCellOrOtherSpeculation):
+ (JSC::isNotCellSpeculation):
+ * dfg/DFGFixupPhase.cpp:
+ (JSC::DFG::FixupPhase::fixupNode):
+ * dfg/DFGNode.h:
+ (JSC::DFG::Node::shouldSpeculateCell):
+ (JSC::DFG::Node::shouldSpeculateCellOrOther):
+ (JSC::DFG::Node::shouldSpeculateNotCell):
+
2016-03-03 Saam Barati <sbar...@apple.com>
Add Proxy tests for exceptions that depend on an object being non-extensible and having configurable properties
Modified: trunk/Source/_javascript_Core/bytecode/SpeculatedType.h (197541 => 197542)
--- trunk/Source/_javascript_Core/bytecode/SpeculatedType.h 2016-03-04 02:26:49 UTC (rev 197541)
+++ trunk/Source/_javascript_Core/bytecode/SpeculatedType.h 2016-03-04 02:43:53 UTC (rev 197542)
@@ -104,6 +104,11 @@
return !!(value & SpecCell) && !(value & ~SpecCell);
}
+inline bool isCellOrOtherSpeculation(SpeculatedType value)
+{
+ return !!value && !(value & ~(SpecCell | SpecOther));
+}
+
inline bool isNotCellSpeculation(SpeculatedType value)
{
return !(value & SpecCell) && value;
Modified: trunk/Source/_javascript_Core/dfg/DFGFixupPhase.cpp (197541 => 197542)
--- trunk/Source/_javascript_Core/dfg/DFGFixupPhase.cpp 2016-03-04 02:26:49 UTC (rev 197541)
+++ trunk/Source/_javascript_Core/dfg/DFGFixupPhase.cpp 2016-03-04 02:43:53 UTC (rev 197542)
@@ -1064,12 +1064,12 @@
case GetById:
case GetByIdFlush: {
- if (!node->child1()->shouldSpeculateCell())
- break;
-
- // If we hadn't exited because of BadCache, BadIndexingType, or ExoticObjectMode, then
- // leave this as a GetById.
- if (!m_graph.hasExitSite(node->origin.semantic, BadCache)
+ // FIXME: This should be done in the ByteCodeParser based on reading the
+ // PolymorphicAccess, which will surely tell us that this is a AccessCase::ArrayLength.
+ // https://bugs.webkit.org/show_bug.cgi?id=154990
+ if (node->child1()->shouldSpeculateCellOrOther()
+ && !m_graph.hasExitSite(node->origin.semantic, BadType)
+ && !m_graph.hasExitSite(node->origin.semantic, BadCache)
&& !m_graph.hasExitSite(node->origin.semantic, BadIndexingType)
&& !m_graph.hasExitSite(node->origin.semantic, ExoticObjectMode)) {
auto uid = m_graph.identifiers()[node->identifierNumber()];
@@ -1078,7 +1078,9 @@
break;
}
}
- fixEdge<CellUse>(node->child1());
+
+ if (node->child1()->shouldSpeculateCell())
+ fixEdge<CellUse>(node->child1());
break;
}
Modified: trunk/Source/_javascript_Core/dfg/DFGNode.h (197541 => 197542)
--- trunk/Source/_javascript_Core/dfg/DFGNode.h 2016-03-04 02:26:49 UTC (rev 197541)
+++ trunk/Source/_javascript_Core/dfg/DFGNode.h 2016-03-04 02:43:53 UTC (rev 197542)
@@ -2067,6 +2067,11 @@
return isCellSpeculation(prediction());
}
+ bool shouldSpeculateCellOrOther()
+ {
+ return isCellOrOtherSpeculation(prediction());
+ }
+
bool shouldSpeculateNotCell()
{
return isNotCellSpeculation(prediction());
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