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authorLibravatar dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>2024-11-11 15:15:24 +0000
committerLibravatar GitHub <noreply@github.com>2024-11-11 15:15:24 +0000
commit98eef328ea1635436072051b3b3d520ea7071dd5 (patch)
tree7f9969a659b903eb0aab75e5a1e3c6f82272e124 /vendor/golang.org/x/sys/cpu/cpu_darwin_x86.go
parent[chore] update bun libraries to v1.2.5 (#3528) (diff)
downloadgotosocial-98eef328ea1635436072051b3b3d520ea7071dd5.tar.xz
[chore]: Bump golang.org/x/net from 0.30.0 to 0.31.0 (#3536)
Bumps [golang.org/x/net](https://github.com/golang/net) from 0.30.0 to 0.31.0. - [Commits](https://github.com/golang/net/compare/v0.30.0...v0.31.0) --- updated-dependencies: - dependency-name: golang.org/x/net dependency-type: direct:production update-type: version-update:semver-minor ... Signed-off-by: dependabot[bot] <support@github.com> Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Diffstat (limited to 'vendor/golang.org/x/sys/cpu/cpu_darwin_x86.go')
-rw-r--r--vendor/golang.org/x/sys/cpu/cpu_darwin_x86.go61
1 files changed, 61 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/cpu/cpu_darwin_x86.go b/vendor/golang.org/x/sys/cpu/cpu_darwin_x86.go
new file mode 100644
index 000000000..b838cb9e9
--- /dev/null
+++ b/vendor/golang.org/x/sys/cpu/cpu_darwin_x86.go
@@ -0,0 +1,61 @@
+// Copyright 2024 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build darwin && amd64 && gc
+
+package cpu
+
+// darwinSupportsAVX512 checks Darwin kernel for AVX512 support via sysctl
+// call (see issue 43089). It also restricts AVX512 support for Darwin to
+// kernel version 21.3.0 (MacOS 12.2.0) or later (see issue 49233).
+//
+// Background:
+// Darwin implements a special mechanism to economize on thread state when
+// AVX512 specific registers are not in use. This scheme minimizes state when
+// preempting threads that haven't yet used any AVX512 instructions, but adds
+// special requirements to check for AVX512 hardware support at runtime (e.g.
+// via sysctl call or commpage inspection). See issue 43089 and link below for
+// full background:
+// https://github.com/apple-oss-distributions/xnu/blob/xnu-11215.1.10/osfmk/i386/fpu.c#L214-L240
+//
+// Additionally, all versions of the Darwin kernel from 19.6.0 through 21.2.0
+// (corresponding to MacOS 10.15.6 - 12.1) have a bug that can cause corruption
+// of the AVX512 mask registers (K0-K7) upon signal return. For this reason
+// AVX512 is considered unsafe to use on Darwin for kernel versions prior to
+// 21.3.0, where a fix has been confirmed. See issue 49233 for full background.
+func darwinSupportsAVX512() bool {
+ return darwinSysctlEnabled([]byte("hw.optional.avx512f\x00")) && darwinKernelVersionCheck(21, 3, 0)
+}
+
+// Ensure Darwin kernel version is at least major.minor.patch, avoiding dependencies
+func darwinKernelVersionCheck(major, minor, patch int) bool {
+ var release [256]byte
+ err := darwinOSRelease(&release)
+ if err != nil {
+ return false
+ }
+
+ var mmp [3]int
+ c := 0
+Loop:
+ for _, b := range release[:] {
+ switch {
+ case b >= '0' && b <= '9':
+ mmp[c] = 10*mmp[c] + int(b-'0')
+ case b == '.':
+ c++
+ if c > 2 {
+ return false
+ }
+ case b == 0:
+ break Loop
+ default:
+ return false
+ }
+ }
+ if c != 2 {
+ return false
+ }
+ return mmp[0] > major || mmp[0] == major && (mmp[1] > minor || mmp[1] == minor && mmp[2] >= patch)
+}