tree 57db3ae060b7256de20cd60f887e1a18a42fc550
parent 8aab4c94f039132b270ab03968f74d24d315e141
author Ian Lance Taylor <iant@golang.org> 1751343971 -0700
committer Ian Lance Taylor <iant@golang.org> 1752014868 -0700

runtime: avoid libc memmove and memclr

The libc memmove and memclr don't reliably operate on full memory words.
We already avoided them on PPC64, but the same problem can occur even
on x86, where some processors use "rep movsb" and "rep stosb".
Always use C code that stores full memory words.

While we're here, clean up the C code. We don't need special handling
if the memmove/memclr pointers are not pointer-aligned.

Unfortunately, this will likely be slower. Perhaps some day we can
have our own assembly code that operates a word at a time,
or we can use different operations when we know there are no pointers.

Change-Id: I87f66331cc04aa07cb28f59cbc16810dc903c049
Reviewed-on: https://go-review.googlesource.com/c/gofrontend/+/685178
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Than McIntosh <thanm@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>