xs/vendor/github.com/klauspost/reedsolomon/galois_amd64.go

93 lines
1.9 KiB
Go

//+build !noasm
//+build !appengine
//+build !gccgo
// Copyright 2015, Klaus Post, see LICENSE for details.
package reedsolomon
//go:noescape
func galMulSSSE3(low, high, in, out []byte)
//go:noescape
func galMulSSSE3Xor(low, high, in, out []byte)
//go:noescape
func galMulAVX2Xor(low, high, in, out []byte)
//go:noescape
func galMulAVX2(low, high, in, out []byte)
//go:noescape
func sSE2XorSlice(in, out []byte)
// This is what the assembler routines do in blocks of 16 bytes:
/*
func galMulSSSE3(low, high, in, out []byte) {
for n, input := range in {
l := input & 0xf
h := input >> 4
out[n] = low[l] ^ high[h]
}
}
func galMulSSSE3Xor(low, high, in, out []byte) {
for n, input := range in {
l := input & 0xf
h := input >> 4
out[n] ^= low[l] ^ high[h]
}
}
*/
func galMulSlice(c byte, in, out []byte, o *options) {
var done int
if o.useAVX2 {
galMulAVX2(mulTableLow[c][:], mulTableHigh[c][:], in, out)
done = (len(in) >> 5) << 5
} else if o.useSSSE3 {
galMulSSSE3(mulTableLow[c][:], mulTableHigh[c][:], in, out)
done = (len(in) >> 4) << 4
}
remain := len(in) - done
if remain > 0 {
mt := mulTable[c][:256]
for i := done; i < len(in); i++ {
out[i] = mt[in[i]]
}
}
}
func galMulSliceXor(c byte, in, out []byte, o *options) {
var done int
if o.useAVX2 {
galMulAVX2Xor(mulTableLow[c][:], mulTableHigh[c][:], in, out)
done = (len(in) >> 5) << 5
} else if o.useSSSE3 {
galMulSSSE3Xor(mulTableLow[c][:], mulTableHigh[c][:], in, out)
done = (len(in) >> 4) << 4
}
remain := len(in) - done
if remain > 0 {
mt := mulTable[c][:256]
for i := done; i < len(in); i++ {
out[i] ^= mt[in[i]]
}
}
}
// slice galois add
func sliceXor(in, out []byte, sse2 bool) {
var done int
if sse2 {
sSE2XorSlice(in, out)
done = (len(in) >> 4) << 4
}
remain := len(in) - done
if remain > 0 {
for i := done; i < len(in); i++ {
out[i] ^= in[i]
}
}
}