cubefs

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//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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	sliceXorGo(in, out, o)
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}
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// 4-way butterfly
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func ifftDIT4(work [][]byte, dist int, log_m01, log_m23, log_m02 ffe, o *options) {
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	ifftDIT4Ref(work, dist, log_m01, log_m23, log_m02, o)
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}
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// 4-way butterfly
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func ifftDIT48(work [][]byte, dist int, log_m01, log_m23, log_m02 ffe8, o *options) {
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	ifftDIT4Ref8(work, dist, log_m01, log_m23, log_m02, o)
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}
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// 4-way butterfly
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func fftDIT4(work [][]byte, dist int, log_m01, log_m23, log_m02 ffe, o *options) {
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	fftDIT4Ref(work, dist, log_m01, log_m23, log_m02, o)
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}
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// 4-way butterfly
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func fftDIT48(work [][]byte, dist int, log_m01, log_m23, log_m02 ffe8, o *options) {
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	fftDIT4Ref8(work, dist, log_m01, log_m23, log_m02, o)
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}
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// 2-way butterfly forward
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func fftDIT2(x, y []byte, log_m ffe, o *options) {
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	// Reference version:
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	refMulAdd(x, y, log_m)
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	sliceXorGo(x, y, o)
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}
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// 2-way butterfly forward
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func fftDIT28(x, y []byte, log_m ffe8, o *options) {
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	// Reference version:
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	mulAdd8(x, y, log_m, o)
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	sliceXorGo(x, y, o)
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}
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// 2-way butterfly inverse
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func ifftDIT2(x, y []byte, log_m ffe, o *options) {
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	// Reference version:
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	sliceXorGo(x, y, o)
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	refMulAdd(x, y, log_m)
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}
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// 2-way butterfly inverse
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func ifftDIT28(x, y []byte, log_m ffe8, o *options) {
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	// Reference version:
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	sliceXorGo(x, y, o)
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	mulAdd8(x, y, log_m, o)
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}
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func mulgf16(x, y []byte, log_m ffe, o *options) {
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	refMul(x, y, log_m)
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}
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func mulAdd8(out, in []byte, log_m ffe8, o *options) {
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	t := &multiply256LUT8[log_m]
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	galMulPpcXor(t[:16], t[16:32], in, out)
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	done := (len(in) >> 4) << 4
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	in = in[done:]
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	if len(in) > 0 {
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		out = out[done:]
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		refMulAdd8(in, out, log_m)
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	}
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}
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func mulgf8(out, in []byte, log_m ffe8, o *options) {
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	var done int
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	t := &multiply256LUT8[log_m]
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	galMulPpc(t[:16], t[16:32], in, out)
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	done = (len(in) >> 4) << 4
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	remain := len(in) - done
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	if remain > 0 {
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		mt := mul8LUTs[log_m].Value[:]
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		for i := done; i < len(in); i++ {
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			out[i] ^= byte(mt[in[i]])
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		}
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	}
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}
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