[webkit-changes] [WebKit/WebKit] 1f6f5b: Add <functional> to precompiled header set

[Commit Queue]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 1f6f5b1e5d879b8c2c3e41f76bf51325d7586847
      https://github.com/WebKit/WebKit/commit/1f6f5b1e5d879b8c2c3e41f76bf51325d7586847
  Author: Brent Fulgham <bfulgham at webkit.org>
  Date:   2023-03-10 (Fri, 10 Mar 2023)

  Changed paths:
    M Source/WebCore/WebCorePrefix.h
    M Source/WebKit/WebKit2Prefix.h

  Log Message:
  -----------
  Add <functional> to precompiled header set
https://bugs.webkit.org/show_bug.cgi?id=253725
<rdar://problem/106562509>

Reviewed by Tim Horton.

One of the most costly headers across the build is boyer_moore_searcher.h, which is
used inside <functional>. The file is included 2499 times, and only changes (sometimes)
when the SDK is updated.

We should precompile it!

Before the proposed change (M1 Pro):
Compilation (10226 times):
  Parsing (frontend):         9479.2 s
  Codegen & opts (backend):   3429.0 s

With the change:
Compilation (10196 times):
  Parsing (frontend):         9312.7 s
  Codegen & opts (backend):   3316.7 s

* Source/WebCore/WebCorePrefix.h:
* Source/WebKit/WebKit2Prefix.h:

Canonical link: https://commits.webkit.org/261531@main