Title: [127974] trunk/Source/WebCore
- Revision
- 127974
- Author
- [email protected]
- Date
- 2012-09-08 17:35:47 -0700 (Sat, 08 Sep 2012)
Log Message
Specialize nextBreakablePosition depending on breakNBSP
https://bugs.webkit.org/show_bug.cgi?id=96042
Patch by Benjamin Poulain <[email protected]> on 2012-09-08
Reviewed by Eric Seidel.
The speed of isBreakableSpace() is limited by the speed of the inner loop of nextBreakablePosition().
The branches done to handle noBreakSpace can be simplified outside the loop
to reduce the number of tests inside the loop.
This patch split the code of nextBreakablePosition() in two function, depending if breakNBSP is true
or false.
If breakNBSP is true, isBreakableSpace() would return true on noBreakSpace.
->There is no need to test that value again for needsLineBreakIterator().
->There is no need to special case the switch() of isBreakableSpace() for noBreakSpace.
If breakNBSP is false:
->isBreakableSpace() does not need to test for noBreakSpace.
On x86_64, this improves PerformanceTests/Layout/line-layout.html by 2.8%.
* rendering/break_lines.cpp:
(WebCore::isBreakableSpace):
(WebCore::nextBreakablePositionIgnoringNBSP):
(WebCore::nextBreakablePosition):
* rendering/break_lines.h:
(WebCore::isBreakable): Remove the default value for breakNBSP, no caller is using it.
Modified Paths
Diff
Modified: trunk/Source/WebCore/ChangeLog (127973 => 127974)
--- trunk/Source/WebCore/ChangeLog 2012-09-08 19:50:03 UTC (rev 127973)
+++ trunk/Source/WebCore/ChangeLog 2012-09-09 00:35:47 UTC (rev 127974)
@@ -1,3 +1,33 @@
+2012-09-08 Benjamin Poulain <[email protected]>
+
+ Specialize nextBreakablePosition depending on breakNBSP
+ https://bugs.webkit.org/show_bug.cgi?id=96042
+
+ Reviewed by Eric Seidel.
+
+ The speed of isBreakableSpace() is limited by the speed of the inner loop of nextBreakablePosition().
+ The branches done to handle noBreakSpace can be simplified outside the loop
+ to reduce the number of tests inside the loop.
+
+ This patch split the code of nextBreakablePosition() in two function, depending if breakNBSP is true
+ or false.
+
+ If breakNBSP is true, isBreakableSpace() would return true on noBreakSpace.
+ ->There is no need to test that value again for needsLineBreakIterator().
+ ->There is no need to special case the switch() of isBreakableSpace() for noBreakSpace.
+
+ If breakNBSP is false:
+ ->isBreakableSpace() does not need to test for noBreakSpace.
+
+ On x86_64, this improves PerformanceTests/Layout/line-layout.html by 2.8%.
+
+ * rendering/break_lines.cpp:
+ (WebCore::isBreakableSpace):
+ (WebCore::nextBreakablePositionIgnoringNBSP):
+ (WebCore::nextBreakablePosition):
+ * rendering/break_lines.h:
+ (WebCore::isBreakable): Remove the default value for breakNBSP, no caller is using it.
+
2012-09-08 Adam Barth <[email protected]>
[V8] DOM wrapper creation involves a bunch of sketchy code related to finding the Frame
Modified: trunk/Source/WebCore/rendering/break_lines.cpp (127973 => 127974)
--- trunk/Source/WebCore/rendering/break_lines.cpp 2012-09-08 19:50:03 UTC (rev 127973)
+++ trunk/Source/WebCore/rendering/break_lines.cpp 2012-09-09 00:35:47 UTC (rev 127974)
@@ -38,7 +38,8 @@
namespace WebCore {
-static inline bool isBreakableSpace(UChar ch, bool treatNoBreakSpaceAsBreak)
+template<bool treatNoBreakSpaceAsBreak>
+static inline bool isBreakableSpace(UChar ch)
{
switch (ch) {
case ' ':
@@ -138,12 +139,16 @@
return false;
}
-static inline bool needsLineBreakIterator(UChar ch)
+template<bool treatNoBreakSpaceAsBreak>
+inline bool needsLineBreakIterator(UChar ch)
{
+ if (treatNoBreakSpaceAsBreak)
+ return ch > asciiLineBreakTableLastChar;
return ch > asciiLineBreakTableLastChar && ch != noBreakSpace;
}
-int nextBreakablePosition(LazyLineBreakIterator& lazyBreakIterator, int pos, bool treatNoBreakSpaceAsBreak)
+template<bool treatNoBreakSpaceAsBreak>
+static inline int nextBreakablePosition(LazyLineBreakIterator& lazyBreakIterator, int pos)
{
const UChar* str = lazyBreakIterator.string();
int len = lazyBreakIterator.length();
@@ -154,16 +159,16 @@
for (int i = pos; i < len; i++) {
UChar ch = str[i];
- if (isBreakableSpace(ch, treatNoBreakSpaceAsBreak) || shouldBreakAfter(lastLastCh, lastCh, ch))
+ if (isBreakableSpace<treatNoBreakSpaceAsBreak>(ch) || shouldBreakAfter(lastLastCh, lastCh, ch))
return i;
- if (needsLineBreakIterator(ch) || needsLineBreakIterator(lastCh)) {
+ if (needsLineBreakIterator<treatNoBreakSpaceAsBreak>(ch) || needsLineBreakIterator<treatNoBreakSpaceAsBreak>(lastCh)) {
if (nextBreak < i && i) {
TextBreakIterator* breakIterator = lazyBreakIterator.get();
if (breakIterator)
nextBreak = textBreakFollowing(breakIterator, i - 1);
}
- if (i == nextBreak && !isBreakableSpace(lastCh, treatNoBreakSpaceAsBreak))
+ if (i == nextBreak && !isBreakableSpace<treatNoBreakSpaceAsBreak>(lastCh))
return i;
}
@@ -174,4 +179,14 @@
return len;
}
+int nextBreakablePositionIgnoringNBSP(LazyLineBreakIterator& lazyBreakIterator, int pos)
+{
+ return nextBreakablePosition<false>(lazyBreakIterator, pos);
+}
+
+int nextBreakablePosition(LazyLineBreakIterator& lazyBreakIterator, int pos)
+{
+ return nextBreakablePosition<true>(lazyBreakIterator, pos);
+}
+
} // namespace WebCore
Modified: trunk/Source/WebCore/rendering/break_lines.h (127973 => 127974)
--- trunk/Source/WebCore/rendering/break_lines.h 2012-09-08 19:50:03 UTC (rev 127973)
+++ trunk/Source/WebCore/rendering/break_lines.h 2012-09-09 00:35:47 UTC (rev 127974)
@@ -27,12 +27,17 @@
class LazyLineBreakIterator;
-int nextBreakablePosition(LazyLineBreakIterator&, int pos, bool breakNBSP = false);
+int nextBreakablePositionIgnoringNBSP(LazyLineBreakIterator&, int pos);
+int nextBreakablePosition(LazyLineBreakIterator&, int pos);
-inline bool isBreakable(LazyLineBreakIterator& lazyBreakIterator, int pos, int& nextBreakable, bool breakNBSP = false)
+inline bool isBreakable(LazyLineBreakIterator& lazyBreakIterator, int pos, int& nextBreakable, bool breakNBSP)
{
- if (pos > nextBreakable)
- nextBreakable = nextBreakablePosition(lazyBreakIterator, pos, breakNBSP);
+ if (pos > nextBreakable) {
+ if (breakNBSP)
+ nextBreakable = nextBreakablePosition(lazyBreakIterator, pos);
+ else
+ nextBreakable = nextBreakablePositionIgnoringNBSP(lazyBreakIterator, pos);
+ }
return pos == nextBreakable;
}
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