Bug 154772

Summary: Optimize parseHTMLInteger()
Product: WebKit Reporter: Chris Dumez <cdumez>
Component: DOMAssignee: Chris Dumez <cdumez>
Status: RESOLVED FIXED    
Severity: Normal CC: commit-queue, darin, esprehn+autocc, gyuyoung.kim, rniwa, sam
Priority: P2    
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
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Description Chris Dumez 2016-02-26 21:43:16 PST
Optimize parseHTMLInteger() now that it is used a lot more and that it has decent API test coverage.
Comment 1 Chris Dumez 2016-02-26 21:53:55 PST
Created attachment 272400 [details]
Patch
Comment 2 Ryosuke Niwa 2016-02-26 22:04:10 PST
Comment on attachment 272400 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=272400&action=review

> Source/WebCore/html/parser/HTMLParserIdioms.cpp:176
> +    value = charactersToIntStrict(numberStart, position - numberStart, &ok);

Can we just compute the result in the above loop instead of calling this function?
We're just parsing decimal number here and we've already traversed the entire string.
Comment 3 Chris Dumez 2016-02-26 22:34:16 PST
Created attachment 272409 [details]
Patch
Comment 4 Ryosuke Niwa 2016-02-26 22:49:58 PST
Comment on attachment 272409 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=272409&action=review

> Source/WebCore/html/parser/HTMLParserIdioms.cpp:178
> +    int result = 0;

Why don't we use unsigned here

> Source/WebCore/html/parser/HTMLParserIdioms.cpp:182
> +        if (result > maxMultiplier || (result == maxMultiplier && digitValue > (intMax % base) + isNegative))

So that we can simplify the second condition here?

Now that I'm seeing this code for overflow check, perhaps calling charactersToIntStrict wasn't that bad...
Comment 5 Chris Dumez 2016-02-27 09:43:13 PST
Created attachment 272418 [details]
Patch
Comment 6 WebKit Commit Bot 2016-02-27 10:30:52 PST
Comment on attachment 272418 [details]
Patch

Clearing flags on attachment: 272418

Committed r197255: <http://trac.webkit.org/changeset/197255>
Comment 7 WebKit Commit Bot 2016-02-27 10:30:56 PST
All reviewed patches have been landed.  Closing bug.