Commit Graph

2 Commits

Author SHA1 Message Date
Polina Osadcha
0cf7623e9d cpu: add GODEBUG options to disable use of instruction set extensions
The GODEBUG environment variable can be used to disable usage of
specific processor features of Go programs that use the sys/cpu package.
This is useful for testing and benchmarking different code paths that
are guarded by sys/cpu variable checks.

Use of processor features can not be enabled through GODEBUG.

To disable usage of AVX and SSE41 cpu features on GOARCH amd64 use:
GODEBUG=cpu.avx=off,cpu.sse41=off

The special "all" option can be used to disable all options:
GODEBUG=all=off

This aligns the support of GODEBUG for sys/cpu with existing support
for GODEBUG in the Go standard library package internal/cpu.

Fixes golang/go#33963

Change-Id: I618b71af397bf06c57a49b2a300d032a16d05664
Reviewed-on: https://go-review.googlesource.com/c/sys/+/245237
Run-TryBot: Martin Möhrmann <moehrmann@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>
Reviewed-by: Tobias Klauser <tobias.klauser@gmail.com>
2020-08-05 06:55:43 +00:00
Tobias Klauser
2f3576d2c5 cpu: add basic support for GOARCH=riscv64
Updates golang/go#27532

Change-Id: I7250f272ff46f2765d498a97644fb570ae745a6c
Reviewed-on: https://go-review.googlesource.com/c/sys/+/206860
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
2019-11-13 15:47:02 +00:00