mirror of
https://github.com/octoleo/syncthing.git
synced 2024-11-10 07:11:08 +00:00
56 lines
1.4 KiB
Go
56 lines
1.4 KiB
Go
// Minio Cloud Storage, (C) 2016 Minio, Inc.
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
//
|
|
|
|
package sha256
|
|
|
|
// True when SIMD instructions are available.
|
|
var avx2 = haveAVX2()
|
|
var avx = haveAVX()
|
|
var ssse3 = haveSSSE3()
|
|
var armSha = haveArmSha()
|
|
|
|
// haveAVX returns true when there is AVX support
|
|
func haveAVX() bool {
|
|
_, _, c, _ := cpuid(1)
|
|
|
|
// Check XGETBV, OXSAVE and AVX bits
|
|
if c&(1<<26) != 0 && c&(1<<27) != 0 && c&(1<<28) != 0 {
|
|
// Check for OS support
|
|
eax, _ := xgetbv(0)
|
|
return (eax & 0x6) == 0x6
|
|
}
|
|
return false
|
|
}
|
|
|
|
// haveAVX2 returns true when there is AVX2 support
|
|
func haveAVX2() bool {
|
|
mfi, _, _, _ := cpuid(0)
|
|
|
|
// Check AVX2, AVX2 requires OS support, but BMI1/2 don't.
|
|
if mfi >= 7 && haveAVX() {
|
|
_, ebx, _, _ := cpuidex(7, 0)
|
|
return (ebx & 0x00000020) != 0
|
|
}
|
|
return false
|
|
}
|
|
|
|
// haveSSSE3 returns true when there is SSSE3 support
|
|
func haveSSSE3() bool {
|
|
|
|
_, _, c, _ := cpuid(1)
|
|
|
|
return (c & 0x00000200) != 0
|
|
}
|