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//+build !noasm
//+build !appengine
//+build !gccgo
// Copyright 2015, Klaus Post, see LICENSE for details.
// Copyright 2018, Minio, Inc.
package reedsolomon
//go:noescape
func galMulPpc(low, high, in, out []byte)
//go:noescape
func galMulPpcXor(low, high, in, out []byte)
// This is what the assembler routines do in blocks of 16 bytes:
/*
func galMulPpc(low, high, in, out []byte) {
for n, input := range in {
l := input & 0xf
h := input >> 4
out[n] = low[l] ^ high[h]
}
}
func galMulPpcXor(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) {
if c == 1 {
copy(out, in)
return
}
done := (len(in) >> 4) << 4
if done > 0 {
galMulPpc(mulTableLow[c][:], mulTableHigh[c][:], in[:done], out)
}
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) {
if c == 1 {
sliceXor(in, out, o)
return
}
done := (len(in) >> 4) << 4
if done > 0 {
galMulPpcXor(mulTableLow[c][:], mulTableHigh[c][:], in[:done], out)
}
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, o *options) {
for n, input := range in {
out[n] ^= input
}
}
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