[webkit-reviews] review denied: [Bug 121899] Optimize strings copies in srcset parser : [Attachment 212732] Patch

[bugzilla-daemon at webkit.org]

Benjamin Poulain <benjamin at webkit.org> has denied Romain Perier
<romain.perier at gmail.com>'s request for review:
Bug 121899: Optimize strings copies in srcset parser
https://bugs.webkit.org/show_bug.cgi?id=121899

Attachment 212732: Patch
https://bugs.webkit.org/attachment.cgi?id=212732&action=review

------- Additional Comments from Benjamin Poulain <benjamin at webkit.org>
View in context: https://bugs.webkit.org/attachment.cgi?id=212732&action=review


> Source/WebCore/html/parser/HTMLParserIdioms.cpp:303
> +    size_t imageURLStart;

String length are unsigned. You should have imageURLStart unsigned .

> Source/WebCore/html/parser/HTMLParserIdioms.cpp:309
> +	   return !imageURLStart && !imageURLLength;

Isn't !imageURLLength enough?

The method should probably be hasImageURL() and the caller use "!hasImage()".

>> Source/WebCore/html/parser/HTMLParserIdioms.cpp:433
>> -		return String(imageCandidates[i].imageURL);
>> +		return imageCandidates[i].hasNoImage() ? srcAttribute :
String(srcsetAttribute.characters() + imageCandidates[i].imageURLStart,
imageCandidates[i].imageURLLength);
>>	}
>> -	return String(imageCandidates.last().imageURL);
>> +	return imageCandidates.last().hasNoImage() ? srcAttribute :
String(srcsetAttribute.characters() + imageCandidates.last().imageURLStart,
imageCandidates.last().imageURLLength);
> 
> Please use srcsetAttribute.substring() instead. That's more readable, and
could help future optimizations.
> 
> Also, I'd use a local variable for imageCandidates.last().

substring() would be better indeed. StringImpl::substring takes into account
the 8/16 bits strings.
You could even use String::substringSharingImpl() here since srcsetAttribute
will stay alive anyway.