[webkit-changes] [WebKit/WebKit] 602101: [JSC] Clear locals efficiently in WasmBBQ

[Yusuke Suzuki]

  Branch: refs/heads/main
  Home:   https://github.com/WebKit/WebKit
  Commit: 602101c35e26ecacc9d56980d9eae0b5716ad98d
      https://github.com/WebKit/WebKit/commit/602101c35e26ecacc9d56980d9eae0b5716ad98d
  Author: Yusuke Suzuki <ysuzuki at apple.com>
  Date:   2023-03-06 (Mon, 06 Mar 2023)

  Changed paths:
    M Source/JavaScriptCore/wasm/WasmBBQJIT.cpp

  Log Message:
  -----------
  [JSC] Clear locals efficiently in WasmBBQ
https://bugs.webkit.org/show_bug.cgi?id=253424
rdar://106269732

Reviewed by Mark Lam.

Locals are siblings in the stack locations and most of them are cleared via zeros.
This patch buffers local clearing and do efficient zero clear by using stp.

* Source/JavaScriptCore/wasm/WasmBBQJIT.cpp:
(JSC::Wasm::BBQJIT::sizeOfType):
(JSC::Wasm::BBQJIT::Value::size const):
(JSC::Wasm::BBQJIT::addTopLevel):

Canonical link: https://commits.webkit.org/261257@main