Bug 204481 – Optimize String.prototype.replace() and replaceAll() for string searches.

• Status: ASSIGNED
• Component: JavaScriptCore

[Mark Lam]

...

[Mark Lam]

I created 3 microbenchmarks based on string-replace.js, string-replace-generic.js, and string-replace-empty.js, but use "f" as the searchValue instead of /f/g.  With these, I see that the patch in https://bugs.webkit.org/show_bug.cgi?id=202471 did indeed regressed performance:

                                               Old                       New
string-replace-generic-2                       30.0312+-1.2393     !     34.9829+-1.4384        ! definitely 1.1649x slower
string-replace-2                               29.4600+-1.1706     !     33.9296+-2.0799        ! definitely 1.1517x slower
string-replace-empty-2                         20.7875+-0.4358     !     24.9824+-1.1148        ! definitely 1.2018x slower