go-ethereum/common/hexutil/asmhex/asmhex_amd64.go
2024-06-26 22:58:34 +03:00

80 lines
1.7 KiB
Go

// Copyright 2016 Tom Thorogood. All rights reserved.
// Use of this source code is governed by a
// Modified BSD License license that can be found in
// the LICENSE file.
//go:build amd64 && !gccgo && !appengine
package asmhex
import (
"encoding/hex"
"golang.org/x/sys/cpu"
)
func Encode(dst, src []byte) int {
if len(dst) < len(src)*2 {
panic("dst buffer is too small")
}
if len(src) == 0 {
return 0
}
switch {
case cpu.X86.HasAVX:
encodeAVX(&dst[0], &src[0], uint64(len(src)), &alphabet[0])
case cpu.X86.HasSSE41:
encodeSSE(&dst[0], &src[0], uint64(len(src)), &alphabet[0])
default:
return hex.Encode(dst, src)
}
return len(src) * 2
}
func Decode(dst, src []byte) (int, error) {
if len(src)%2 != 0 {
return 0, hex.ErrLength
}
if len(dst) < len(src)/2 {
panic("dst buffer is too small")
}
if len(src) == 0 {
return 0, nil
}
var (
n uint64
ok bool
)
switch {
case cpu.X86.HasAVX:
n, ok = decodeAVX(&dst[0], &src[0], uint64(len(src)))
case cpu.X86.HasSSE41:
n, ok = decodeSSE(&dst[0], &src[0], uint64(len(src)))
default:
return hex.Decode(dst, src)
}
if !ok {
return 0, hex.InvalidByteError(src[n])
}
return len(src) / 2, nil
}
// This function is implemented in asmhex_encode_amd64.s
//
//go:noescape
func encodeAVX(dst *byte, src *byte, len uint64, alpha *byte)
// This function is implemented in asmhex_encode_amd64.s
//
//go:noescape
func encodeSSE(dst *byte, src *byte, len uint64, alpha *byte)
// This function is implemented in asmhex_decode_amd64.s
//
//go:noescape
func decodeAVX(dst *byte, src *byte, len uint64) (n uint64, ok bool)
// This function is implemented in asmhex_decode_amd64.s
//
//go:noescape
func decodeSSE(dst *byte, src *byte, len uint64) (n uint64, ok bool)