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.
Fixesgolang/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>
The current implementation for ppc64{,le} only supports linux (through
HWCaps read from /proc/self/auxv) and fails to build e.g. on
aix/ppc64.
Change-Id: I5e1efe75c781fd08bc7bbe797df88295726ba62b
Reviewed-on: https://go-review.googlesource.com/c/162798
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
This CL introduces a new cpu package for CPU/platform feature detection.
The cpu package is basically a copy of `internal/cpu` of the standard library.
Revision: bf86aec25972f3a100c3aa58a6abcbcc35bdea49
This CL does not export ARM64 and PPC64 feature detection since at the moment
ARM64/PPC64 requires standard library support.
Updates golang/go#24843
Change-Id: I11bc1ca60b116e902c941b5887c00870dbb1f899
Reviewed-on: https://go-review.googlesource.com/107015
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
