tree ccf0377dd82c0a1e3e953b23c3c515fb73387a80
parent 7a9ce7465575ac1bfda3aa44b95712cdd5dc47cf
author Rongrong <rongrong@oss.cipunited.com> 1669010740 +0800
committer Meng Zhuo <mzh@golangcn.org> 1669263143 +0000

syscall, runtime/internal/syscall: zero r2 before mips linux syscalls

All mips variant perform syscalls similarly. R2 (v0) holds r1 and R3
(v1) holds r2 of a syscall. The latter is only used by 2-ret syscalls.
A 1-ret syscall would not touch R3 but keeps it as is, making r2 be a
random value. Always reset it to 0 before SYSCALL to fix the issue.

Fixes #56426

Change-Id: Ie49965c0c3c224c4a895703ac659205cd040ff56
Reviewed-on: https://go-review.googlesource.com/c/go/+/452975
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Meng Zhuo <mzh@golangcn.org>
Reviewed-by: Austin Clements <austin@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Meng Zhuo <mzh@golangcn.org>