mirror of https://gogs.blitter.com/RLabs/xs
75 lines
1.5 KiB
Go
75 lines
1.5 KiB
Go
//go:build !noasm && !appengine && !gccgo
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// +build !noasm,!appengine,!gccgo
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// Copyright 2015, Klaus Post, see LICENSE for details.
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// Copyright 2018, Minio, Inc.
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package reedsolomon
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//go:noescape
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func galMulPpc(low, high, in, out []byte)
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//go:noescape
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func galMulPpcXor(low, high, in, out []byte)
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// This is what the assembler routines do in blocks of 16 bytes:
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/*
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func galMulPpc(low, high, in, out []byte) {
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for n, input := range in {
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l := input & 0xf
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h := input >> 4
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out[n] = low[l] ^ high[h]
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}
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}
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func galMulPpcXor(low, high, in, out []byte) {
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for n, input := range in {
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l := input & 0xf
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h := input >> 4
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out[n] ^= low[l] ^ high[h]
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}
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}
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*/
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func galMulSlice(c byte, in, out []byte, o *options) {
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if c == 1 {
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copy(out, in)
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return
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}
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done := (len(in) >> 4) << 4
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if done > 0 {
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galMulPpc(mulTableLow[c][:], mulTableHigh[c][:], in[:done], out)
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}
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remain := len(in) - done
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if remain > 0 {
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mt := mulTable[c][:256]
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for i := done; i < len(in); i++ {
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out[i] = mt[in[i]]
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}
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}
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}
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func galMulSliceXor(c byte, in, out []byte, o *options) {
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if c == 1 {
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sliceXor(in, out, o)
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return
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}
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done := (len(in) >> 4) << 4
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if done > 0 {
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galMulPpcXor(mulTableLow[c][:], mulTableHigh[c][:], in[:done], out)
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}
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remain := len(in) - done
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if remain > 0 {
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mt := mulTable[c][:256]
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for i := done; i < len(in); i++ {
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out[i] ^= mt[in[i]]
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}
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}
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}
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// slice galois add
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func sliceXor(in, out []byte, o *options) {
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for n, input := range in {
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out[n] ^= input
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}
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}
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