Updated version of klauspost/reedsolomon using proper AVX2 instructions as well a providing support for Cauchy matrices. (#5215)

7 years ago · 6e6aeb6a9e
parent c9e00ae0a5
commit 6e6aeb6a9e
6 changed files with 85 additions and 43 deletions
--- a/vendor/github.com/klauspost/reedsolomon/README.md
+++ b/vendor/github.com/klauspost/reedsolomon/README.md
@ -24,10 +24,15 @@ go get -u github.com/klauspost/reedsolomon

 # Changes

-## August 26, 2017
+## October 1, 2017
+
+* [Cauchy Matrix](https://godoc.org/github.com/klauspost/reedsolomon#WithCauchyMatrix) is now an option. Thanks to [templexxx](https://github.com/templexxx) for the basis of this.
+* Default maximum number of [goroutines](https://godoc.org/github.com/klauspost/reedsolomon#WithMaxGoroutines) has been increased for better multi-core scaling.
+* After several requests the Reconstruct and ReconstructData now slices of zero length but sufficient capacity to be used instead of allocating new memory.

-*  The[`Encoder()`](https://godoc.org/github.com/klauspost/reedsolomon#Encoder) now contains an `Update` function contributed by [chenzhongtao](https://github.com/chenzhongtao).
+## August 26, 2017

+*  The [`Encoder()`](https://godoc.org/github.com/klauspost/reedsolomon#Encoder) now contains an `Update` function contributed by [chenzhongtao](https://github.com/chenzhongtao).
 * [Frank Wessels](https://github.com/fwessels) kindly contributed ARM 64 bit assembly, which gives a huge performance boost on this platform.

 ## July 20, 2017
@ -155,7 +160,7 @@ It might seem like a limitation that all data should be in memory, but an import
      splitA[i] = data[i][:25000]
      splitB[i] = data[i][25000:]
      
-      // Concencate it to itself
+      // Concatenate it to itself
 	  merged[i] = append(make([]byte, 0, len(data[i])*2), data[i]...)
 	  merged[i] = append(merged[i], data[i]...)
    }
--- a/vendor/github.com/klauspost/reedsolomon/galois.go
+++ b/vendor/github.com/klauspost/reedsolomon/galois.go
@ -73,6 +73,9 @@ func galSub(a, b byte) byte {
 	return a ^ b
 }

+// Table from https://github.com/templexxx/reedsolomon
+var invTable = [256]byte{0x0, 0x1, 0x8e, 0xf4, 0x47, 0xa7, 0x7a, 0xba, 0xad, 0x9d, 0xdd, 0x98, 0x3d, 0xaa, 0x5d, 0x96, 0xd8, 0x72, 0xc0, 0x58, 0xe0, 0x3e, 0x4c, 0x66, 0x90, 0xde, 0x55, 0x80, 0xa0, 0x83, 0x4b, 0x2a, 0x6c, 0xed, 0x39, 0x51, 0x60, 0x56, 0x2c, 0x8a, 0x70, 0xd0, 0x1f, 0x4a, 0x26, 0x8b, 0x33, 0x6e, 0x48, 0x89, 0x6f, 0x2e, 0xa4, 0xc3, 0x40, 0x5e, 0x50, 0x22, 0xcf, 0xa9, 0xab, 0xc, 0x15, 0xe1, 0x36, 0x5f, 0xf8, 0xd5, 0x92, 0x4e, 0xa6, 0x4, 0x30, 0x88, 0x2b, 0x1e, 0x16, 0x67, 0x45, 0x93, 0x38, 0x23, 0x68, 0x8c, 0x81, 0x1a, 0x25, 0x61, 0x13, 0xc1, 0xcb, 0x63, 0x97, 0xe, 0x37, 0x41, 0x24, 0x57, 0xca, 0x5b, 0xb9, 0xc4, 0x17, 0x4d, 0x52, 0x8d, 0xef, 0xb3, 0x20, 0xec, 0x2f, 0x32, 0x28, 0xd1, 0x11, 0xd9, 0xe9, 0xfb, 0xda, 0x79, 0xdb, 0x77, 0x6, 0xbb, 0x84, 0xcd, 0xfe, 0xfc, 0x1b, 0x54, 0xa1, 0x1d, 0x7c, 0xcc, 0xe4, 0xb0, 0x49, 0x31, 0x27, 0x2d, 0x53, 0x69, 0x2, 0xf5, 0x18, 0xdf, 0x44, 0x4f, 0x9b, 0xbc, 0xf, 0x5c, 0xb, 0xdc, 0xbd, 0x94, 0xac, 0x9, 0xc7, 0xa2, 0x1c, 0x82, 0x9f, 0xc6, 0x34, 0xc2, 0x46, 0x5, 0xce, 0x3b, 0xd, 0x3c, 0x9c, 0x8, 0xbe, 0xb7, 0x87, 0xe5, 0xee, 0x6b, 0xeb, 0xf2, 0xbf, 0xaf, 0xc5, 0x64, 0x7, 0x7b, 0x95, 0x9a, 0xae, 0xb6, 0x12, 0x59, 0xa5, 0x35, 0x65, 0xb8, 0xa3, 0x9e, 0xd2, 0xf7, 0x62, 0x5a, 0x85, 0x7d, 0xa8, 0x3a, 0x29, 0x71, 0xc8, 0xf6, 0xf9, 0x43, 0xd7, 0xd6, 0x10, 0x73, 0x76, 0x78, 0x99, 0xa, 0x19, 0x91, 0x14, 0x3f, 0xe6, 0xf0, 0x86, 0xb1, 0xe2, 0xf1, 0xfa, 0x74, 0xf3, 0xb4, 0x6d, 0x21, 0xb2, 0x6a, 0xe3, 0xe7, 0xb5, 0xea, 0x3, 0x8f, 0xd3, 0xc9, 0x42, 0xd4, 0xe8, 0x75, 0x7f, 0xff, 0x7e, 0xfd}
+
 var mulTable = [256][256]uint8{[256]uint8{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0},
 	{0x0, 0x1, 0x2, 0x3, 0x4, 0x5, 0x6, 0x7, 0x8, 0x9, 0xa, 0xb, 0xc, 0xd, 0xe, 0xf, 0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f, 0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f, 0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f, 0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f, 0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f, 0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf, 0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf, 0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf, 0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf, 0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef, 0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff},
 	{0x0, 0x2, 0x4, 0x6, 0x8, 0xa, 0xc, 0xe, 0x10, 0x12, 0x14, 0x16, 0x18, 0x1a, 0x1c, 0x1e, 0x20, 0x22, 0x24, 0x26, 0x28, 0x2a, 0x2c, 0x2e, 0x30, 0x32, 0x34, 0x36, 0x38, 0x3a, 0x3c, 0x3e, 0x40, 0x42, 0x44, 0x46, 0x48, 0x4a, 0x4c, 0x4e, 0x50, 0x52, 0x54, 0x56, 0x58, 0x5a, 0x5c, 0x5e, 0x60, 0x62, 0x64, 0x66, 0x68, 0x6a, 0x6c, 0x6e, 0x70, 0x72, 0x74, 0x76, 0x78, 0x7a, 0x7c, 0x7e, 0x80, 0x82, 0x84, 0x86, 0x88, 0x8a, 0x8c, 0x8e, 0x90, 0x92, 0x94, 0x96, 0x98, 0x9a, 0x9c, 0x9e, 0xa0, 0xa2, 0xa4, 0xa6, 0xa8, 0xaa, 0xac, 0xae, 0xb0, 0xb2, 0xb4, 0xb6, 0xb8, 0xba, 0xbc, 0xbe, 0xc0, 0xc2, 0xc4, 0xc6, 0xc8, 0xca, 0xcc, 0xce, 0xd0, 0xd2, 0xd4, 0xd6, 0xd8, 0xda, 0xdc, 0xde, 0xe0, 0xe2, 0xe4, 0xe6, 0xe8, 0xea, 0xec, 0xee, 0xf0, 0xf2, 0xf4, 0xf6, 0xf8, 0xfa, 0xfc, 0xfe, 0x1d, 0x1f, 0x19, 0x1b, 0x15, 0x17, 0x11, 0x13, 0xd, 0xf, 0x9, 0xb, 0x5, 0x7, 0x1, 0x3, 0x3d, 0x3f, 0x39, 0x3b, 0x35, 0x37, 0x31, 0x33, 0x2d, 0x2f, 0x29, 0x2b, 0x25, 0x27, 0x21, 0x23, 0x5d, 0x5f, 0x59, 0x5b, 0x55, 0x57, 0x51, 0x53, 0x4d, 0x4f, 0x49, 0x4b, 0x45, 0x47, 0x41, 0x43, 0x7d, 0x7f, 0x79, 0x7b, 0x75, 0x77, 0x71, 0x73, 0x6d, 0x6f, 0x69, 0x6b, 0x65, 0x67, 0x61, 0x63, 0x9d, 0x9f, 0x99, 0x9b, 0x95, 0x97, 0x91, 0x93, 0x8d, 0x8f, 0x89, 0x8b, 0x85, 0x87, 0x81, 0x83, 0xbd, 0xbf, 0xb9, 0xbb, 0xb5, 0xb7, 0xb1, 0xb3, 0xad, 0xaf, 0xa9, 0xab, 0xa5, 0xa7, 0xa1, 0xa3, 0xdd, 0xdf, 0xd9, 0xdb, 0xd5, 0xd7, 0xd1, 0xd3, 0xcd, 0xcf, 0xc9, 0xcb, 0xc5, 0xc7, 0xc1, 0xc3, 0xfd, 0xff, 0xf9, 0xfb, 0xf5, 0xf7, 0xf1, 0xf3, 0xed, 0xef, 0xe9, 0xeb, 0xe5, 0xe7, 0xe1, 0xe3},
--- a/vendor/github.com/klauspost/reedsolomon/galois_amd64.s
+++ b/vendor/github.com/klauspost/reedsolomon/galois_amd64.s
@ -87,31 +87,31 @@ TEXT ·galMulAVX2Xor(SB), 7, $0
 	MOVQ  high+24(FP), DX   // DX: &high
 	MOVQ  $15, BX           // BX: low mask
 	MOVQ  BX, X5
-	MOVOU (SI), X6          // X6 low
+	MOVOU (SI), X6          // X6: low
 	MOVOU (DX), X7          // X7: high
 	MOVQ  in_len+56(FP), R9 // R9: len(in)

-	LONG $0x384de3c4; WORD $0x01f6 // VINSERTI128 YMM6, YMM6, XMM6, 1 ; low
-	LONG $0x3845e3c4; WORD $0x01ff // VINSERTI128 YMM7, YMM7, XMM7, 1 ; high
-	LONG $0x787d62c4; BYTE $0xc5   // VPBROADCASTB YMM8, XMM5         ; X8: lomask (unpacked)
+	VINSERTI128  $1, X6, Y6, Y6 // low
+	VINSERTI128  $1, X7, Y7, Y7 // high
+	VPBROADCASTB X5, Y8         // Y8: lomask (unpacked)

-	SHRQ  $5, R9         // len(in) /32
+	SHRQ  $5, R9         // len(in) / 32
 	MOVQ  out+72(FP), DX // DX: &out
-	MOVQ  in+48(FP), SI  // R11: &in
+	MOVQ  in+48(FP), SI  // SI: &in
 	TESTQ R9, R9
 	JZ    done_xor_avx2

 loopback_xor_avx2:
-	LONG $0x066ffec5             // VMOVDQU YMM0, [rsi]
-	LONG $0x226ffec5             // VMOVDQU YMM4, [rdx]
-	LONG $0xd073f5c5; BYTE $0x04 // VPSRLQ  YMM1, YMM0, 4   ; X1: high input
-	LONG $0xdb7dc1c4; BYTE $0xc0 // VPAND   YMM0, YMM0, YMM8      ; X0: low input
-	LONG $0xdb75c1c4; BYTE $0xc8 // VPAND   YMM1, YMM1, YMM8      ; X1: high input
-	LONG $0x004de2c4; BYTE $0xd0 // VPSHUFB  YMM2, YMM6, YMM0   ; X2: mul low part
-	LONG $0x0045e2c4; BYTE $0xd9 // VPSHUFB  YMM3, YMM7, YMM1   ; X2: mul high part
-	LONG $0xdbefedc5             // VPXOR   YMM3, YMM2, YMM3    ; X3: Result
-	LONG $0xe4efe5c5             // VPXOR   YMM4, YMM3, YMM4    ; X4: Result
-	LONG $0x227ffec5             // VMOVDQU [rdx], YMM4
+	VMOVDQU (SI), Y0
+	VMOVDQU (DX), Y4
+	VPSRLQ  $4, Y0, Y1 // Y1: high input
+	VPAND   Y8, Y0, Y0 // Y0: low input
+	VPAND   Y8, Y1, Y1 // Y1: high input
+	VPSHUFB Y0, Y6, Y2 // Y2: mul low part
+	VPSHUFB Y1, Y7, Y3 // Y3: mul high part
+	VPXOR   Y3, Y2, Y3 // Y3: Result
+	VPXOR   Y4, Y3, Y4 // Y4: Result
+	VMOVDQU Y4, (DX)

 	ADDQ $32, SI           // in+=32
 	ADDQ $32, DX           // out+=32
@ -119,8 +119,7 @@ loopback_xor_avx2:
 	JNZ  loopback_xor_avx2

 done_xor_avx2:
-	// VZEROUPPER
-	BYTE $0xc5; BYTE $0xf8; BYTE $0x77
+	VZEROUPPER
 	RET

 // func galMulAVX2(low, high, in, out []byte)
@ -129,29 +128,29 @@ TEXT ·galMulAVX2(SB), 7, $0
 	MOVQ  high+24(FP), DX   // DX: &high
 	MOVQ  $15, BX           // BX: low mask
 	MOVQ  BX, X5
-	MOVOU (SI), X6          // X6 low
+	MOVOU (SI), X6          // X6: low
 	MOVOU (DX), X7          // X7: high
 	MOVQ  in_len+56(FP), R9 // R9: len(in)

-	LONG $0x384de3c4; WORD $0x01f6 // VINSERTI128 YMM6, YMM6, XMM6, 1 ; low
-	LONG $0x3845e3c4; WORD $0x01ff // VINSERTI128 YMM7, YMM7, XMM7, 1 ; high
-	LONG $0x787d62c4; BYTE $0xc5   // VPBROADCASTB YMM8, XMM5         ; X8: lomask (unpacked)
+	VINSERTI128  $1, X6, Y6, Y6 // low
+	VINSERTI128  $1, X7, Y7, Y7 // high
+	VPBROADCASTB X5, Y8         // Y8: lomask (unpacked)

-	SHRQ  $5, R9         // len(in) /32
+	SHRQ  $5, R9         // len(in) / 32
 	MOVQ  out+72(FP), DX // DX: &out
-	MOVQ  in+48(FP), SI  // R11: &in
+	MOVQ  in+48(FP), SI  // SI: &in
 	TESTQ R9, R9
 	JZ    done_avx2

 loopback_avx2:
-	LONG $0x066ffec5             // VMOVDQU YMM0, [rsi]
-	LONG $0xd073f5c5; BYTE $0x04 // VPSRLQ  YMM1, YMM0, 4   ; X1: high input
-	LONG $0xdb7dc1c4; BYTE $0xc0 // VPAND   YMM0, YMM0, YMM8      ; X0: low input
-	LONG $0xdb75c1c4; BYTE $0xc8 // VPAND   YMM1, YMM1, YMM8      ; X1: high input
-	LONG $0x004de2c4; BYTE $0xd0 // VPSHUFB  YMM2, YMM6, YMM0   ; X2: mul low part
-	LONG $0x0045e2c4; BYTE $0xd9 // VPSHUFB  YMM3, YMM7, YMM1   ; X2: mul high part
-	LONG $0xe3efedc5             // VPXOR   YMM4, YMM2, YMM3    ; X4: Result
-	LONG $0x227ffec5             // VMOVDQU [rdx], YMM4
+	VMOVDQU (SI), Y0
+	VPSRLQ  $4, Y0, Y1 // Y1: high input
+	VPAND   Y8, Y0, Y0 // Y0: low input
+	VPAND   Y8, Y1, Y1 // Y1: high input
+	VPSHUFB Y0, Y6, Y2 // Y2: mul low part
+	VPSHUFB Y1, Y7, Y3 // Y3: mul high part
+	VPXOR   Y3, Y2, Y4 // Y4: Result
+	VMOVDQU Y4, (DX)

 	ADDQ $32, SI       // in+=32
 	ADDQ $32, DX       // out+=32
@ -159,8 +158,7 @@ loopback_avx2:
 	JNZ  loopback_avx2

 done_avx2:
-
-	BYTE $0xc5; BYTE $0xf8; BYTE $0x77 // VZEROUPPER
+	VZEROUPPER
 	RET

 // func sSE2XorSlice(in, out []byte)
--- a/vendor/github.com/klauspost/reedsolomon/options.go
+++ b/vendor/github.com/klauspost/reedsolomon/options.go
@ -14,10 +14,11 @@ type options struct {
 	minSplitSize               int
 	useAVX2, useSSSE3, useSSE2 bool
 	usePAR1Matrix              bool
+	useCauchy                  bool
 }

 var defaultOptions = options{
-	maxGoroutines: 50,
+	maxGoroutines: 384,
 	minSplitSize:  512,
 }

@ -81,5 +82,17 @@ func withSSE2(enabled bool) Option {
 func WithPAR1Matrix() Option {
 	return func(o *options) {
 		o.usePAR1Matrix = true
+		o.useCauchy = false
+	}
+}
+
+// WithCauchyMatrix will make the encoder build a Cauchy style matrix.
+// The output of this is not compatible with the standard output.
+// A Cauchy matrix is faster to generate. This does not affect data throughput,
+// but will result in slightly faster start-up time.
+func WithCauchyMatrix() Option {
+	return func(o *options) {
+		o.useCauchy = true
+		o.usePAR1Matrix = false
 	}
 }
--- a/vendor/github.com/klauspost/reedsolomon/reedsolomon.go
+++ b/vendor/github.com/klauspost/reedsolomon/reedsolomon.go
@ -183,6 +183,26 @@ func buildMatrixPAR1(dataShards, totalShards int) (matrix, error) {
 	return result, nil
 }

+func buildMatrixCauchy(dataShards, totalShards int) (matrix, error) {
+	result, err := newMatrix(totalShards, dataShards)
+	if err != nil {
+		return nil, err
+	}
+
+	for r, row := range result {
+		// The top portion of the matrix is the identity
+		// matrix, and the bottom is a transposed Cauchy matrix.
+		if r < dataShards {
+			result[r][r] = 1
+		} else {
+			for c := range row {
+				result[r][c] = invTable[(byte(r ^ c))]
+			}
+		}
+	}
+	return result, nil
+}
+
 // New creates a new encoder and initializes it to
 // the number of data shards and parity shards that
 // you want to use. You can reuse this encoder.
@ -208,9 +228,12 @@ func New(dataShards, parityShards int, opts ...Option) (Encoder, error) {
 	}

 	var err error
-	if r.o.usePAR1Matrix {
+	switch {
+	case r.o.useCauchy:
+		r.m, err = buildMatrixCauchy(dataShards, r.Shards)
+	case r.o.usePAR1Matrix:
 		r.m, err = buildMatrixPAR1(dataShards, r.Shards)
-	} else {
+	default:
 		r.m, err = buildMatrix(dataShards, r.Shards)
 	}
 	if err != nil {
--- a/vendor/vendor.json
+++ b/vendor/vendor.json
@ -267,10 +267,10 @@
 			"revisionTime": "2016-10-16T15:41:25Z"
 		},
 		{
-			"checksumSHA1": "sGHmZAWf2bzBFBwL8HPg4u9aJAA=",
+			"checksumSHA1": "Nlhq327ZGeEh1gkPEBNPJKFlwds=",
 			"path": "github.com/klauspost/reedsolomon",
-			"revision": "ddcafc661e43ab1786575c0fc4b5b935b121de05",
-			"revisionTime": "2017-09-20T19:08:25Z"
+			"revision": "e52c150f961e65ab9538bf1276b33bf469f919d8",
+			"revisionTime": "2017-11-18T15:17:31Z"
 		},
 		{
 			"checksumSHA1": "dNYxHiBLalTqluak2/Z8c3RsSEM=",