From 63e8eeac8655f65861b08c86ee6bb465000ad13f Mon Sep 17 00:00:00 2001 From: Evgenii Date: Wed, 4 Sep 2019 10:28:51 +0300 Subject: [PATCH] Determine available features through CPUID --- tz/cpuid_x86.go | 69 +++++++++++++++++++++++++++++++++++++++++++++++++ tz/cpuid_x86.s | 48 ++++++++++++++++++++++++++++++++++ tz/hash.go | 14 +++++++++- 3 files changed, 130 insertions(+), 1 deletion(-) create mode 100644 tz/cpuid_x86.go create mode 100644 tz/cpuid_x86.s diff --git a/tz/cpuid_x86.go b/tz/cpuid_x86.go new file mode 100644 index 0000000..60d0b1b --- /dev/null +++ b/tz/cpuid_x86.go @@ -0,0 +1,69 @@ +// Copyright (c) 2009 The Go Authors. All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +// +build 386 amd64 amd64p32 + +package tz + +const ( + bitOSXSAVE = 1 << 27 + bitAVX = 1 << 28 + bitAVX2 = 1 << 5 +) + +func init() { + maxID, _, _, _ := cpuid(0, 0) + if maxID < 1 { + return + } + + _, _, ecx1, _ := cpuid(1, 0) + hasOSXSAVE = isSet(ecx1, bitOSXSAVE) + + osSupportsAVX := false + if hasOSXSAVE { + eax, _ := xgetbv() + osSupportsAVX = isSet(eax, 1<<1) && isSet(eax, 1<<2) + } + + hasAVX = isSet(ecx1, bitAVX) && osSupportsAVX + + if maxID < 7 { + return + } + + _, ebx7, _, _ := cpuid(7, 0) + hasAVX2 = isSet(ebx7, bitAVX2) && osSupportsAVX +} + +func isSet(hwc uint32, value uint32) bool { + return hwc&value != 0 +} + +func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32) +func xgetbv() (eax, edx uint32) diff --git a/tz/cpuid_x86.s b/tz/cpuid_x86.s new file mode 100644 index 0000000..655744c --- /dev/null +++ b/tz/cpuid_x86.s @@ -0,0 +1,48 @@ +// Copyright (c) 2009 The Go Authors. All rights reserved. +// +// Redistribution and use in source and binary forms, with or without +// modification, are permitted provided that the following conditions are +// met: +// +// * Redistributions of source code must retain the above copyright +// notice, this list of conditions and the following disclaimer. +// * Redistributions in binary form must reproduce the above +// copyright notice, this list of conditions and the following disclaimer +// in the documentation and/or other materials provided with the +// distribution. +// * Neither the name of Google Inc. nor the names of its +// contributors may be used to endorse or promote products derived from +// this software without specific prior written permission. +// +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + +#include "textflag.h" + +// func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32) +TEXT ·cpuid(SB), NOSPLIT, $0-24 + MOVL eaxArg+0(FP), AX + MOVL ecxArg+4(FP), CX + CPUID + MOVL AX, eax+8(FP) + MOVL BX, ebx+12(FP) + MOVL CX, ecx+16(FP) + MOVL DX, edx+20(FP) + RET + +// func xgetbv() (eax, edx uint32) +TEXT ·xgetbv(SB),NOSPLIT,$0-8 + MOVL $0, CX + XGETBV + MOVL AX, eax+0(FP) + MOVL DX, edx+4(FP) + RET diff --git a/tz/hash.go b/tz/hash.go index a7a4380..1ec8612 100644 --- a/tz/hash.go +++ b/tz/hash.go @@ -21,6 +21,12 @@ const ( PureGo ) +var ( + hasAVX bool + hasAVX2 bool + hasOSXSAVE bool +) + func (impl Implementation) String() string { switch impl { case AVX: @@ -53,7 +59,13 @@ func NewWith(impl Implementation) hash.Hash { // New returns a new hash.Hash computing the Tillich-Zémor checksum. func New() hash.Hash { - return newAVX2Inline() + if hasAVX2 { + return newAVX2Inline() + } else if hasAVX { + return newAVX() + } else { + return newPure() + } } // Sum returns Tillich-Zémor checksum of data.