diff --git a/zstd/_generate/gen_matchlen.go b/zstd/_generate/gen_matchlen.go new file mode 100644 index 0000000000..8611f08a50 --- /dev/null +++ b/zstd/_generate/gen_matchlen.go @@ -0,0 +1,107 @@ +package main + +//go:generate go run gen_matchlen.go -out ../matchlen_amd64.s -pkg=zstd + +import ( + "flag" + + . "github.com/mmcloughlin/avo/build" + "github.com/mmcloughlin/avo/buildtags" + . "github.com/mmcloughlin/avo/operand" +) + +func main() { + flag.Parse() + + Constraint(buildtags.Not("appengine").ToConstraint()) + Constraint(buildtags.Not("noasm").ToConstraint()) + Constraint(buildtags.Term("gc").ToConstraint()) + Constraint(buildtags.Not("noasm").ToConstraint()) + generateMatchLen() + Generate() +} + +func generateMatchLen() { + Package("github.com/klauspost/compress/zstd") + TEXT("matchLen", NOSPLIT, "func (a, b []byte) int") + Pragma("noescape") + Comment("load param") + aptr := Load(Param("a").Base(), GP64()) + alen := Load(Param("a").Len(), GP64()) + bptr := Load(Param("b").Base(), GP64()) + equalMaskBits := GP64() + ret := GP64() + XORQ(ret, ret) + + Comment("find the minimum length slice") + remainLen := alen + + Label("loop") + { + CMPQ(remainLen, U8(32)) + JB(LabelRef("last_loop")) + Comment("load 32 bytes into YMM registers") + adata := YMM() + bdata := YMM() + equalMaskBytes := YMM() + VMOVDQU(Mem{Base: aptr}, adata) + VMOVDQU(Mem{Base: bptr}, bdata) + Comment("compare bytes in adata and bdata, like 'bytewise XNOR'", + "if the byte is the same in adata and bdata, VPCMPEQB will store 0xFF in the same position in equalMaskBytes") + VPCMPEQB(adata, bdata, equalMaskBytes) + Comment("like convert byte to bit, store equalMaskBytes into general reg") + VPMOVMSKB(equalMaskBytes, equalMaskBits.As32()) + CMPL(equalMaskBits.As32(), U32(0xffffffff)) + JNE(LabelRef("cal_prefix")) + ADDQ(U8(32), aptr) + ADDQ(U8(32), bptr) + SUBQ(U8(32), remainLen) + ADDQ(U8(32), ret) + JMP(LabelRef("loop")) + } + + Label("last_loop") + { + TESTQ(remainLen, remainLen) + JZ(LabelRef("ret")) + adata := YMM() + bdata := YMM() + equalMaskBytes := YMM() + VMOVDQU(Mem{Base: aptr}, adata) + VMOVDQU(Mem{Base: bptr}, bdata) + VPCMPEQB(adata, bdata, equalMaskBytes) + VPMOVMSKB(equalMaskBytes, equalMaskBits.As32()) + CMPL(equalMaskBits.As32(), U32(0xffffffff)) + JNE(LabelRef("cal_last_prefix")) + Comment("if last bytes are all equal, just add remaining len on ret and return") + ADDQ(remainLen, ret) + JMP(LabelRef("ret")) + } + + Label("cal_last_prefix") + { + matchedLen := GP64() + NOTQ(equalMaskBits) + Comment("store first not equal position into matchedLen") + TZCNTQ(equalMaskBits, matchedLen) + Comment("if matched len > remaining len, just add remaining on ret") + CMPQ(remainLen, matchedLen) + CMOVQLT(remainLen, matchedLen) + ADDQ(matchedLen, ret) + JMP(LabelRef("ret")) + } + + Label("cal_prefix") + { + matchedLen := GP64() + NOTQ(equalMaskBits) + TZCNTQ(equalMaskBits, matchedLen) + ADDQ(matchedLen, ret) + } + + Label("ret") + { + Store(ret, ReturnIndex(0)) + RET() + } +} diff --git a/zstd/_generate/go.mod b/zstd/_generate/go.mod index 175e6df1a8..cdf01a2e3b 100644 --- a/zstd/_generate/go.mod +++ b/zstd/_generate/go.mod @@ -6,7 +6,6 @@ require ( github.com/klauspost/compress v1.15.15 github.com/mmcloughlin/avo v0.5.0 golang.org/x/tools v0.6.0 // indirect - golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2 // indirect ) replace github.com/klauspost/compress => ../.. diff --git a/zstd/_generate/go.sum b/zstd/_generate/go.sum index 4e84b87f87..16418bea45 100644 --- a/zstd/_generate/go.sum +++ b/zstd/_generate/go.sum @@ -1,40 +1,26 @@ -github.com/mmcloughlin/avo v0.4.0 h1:jeHDRktVD+578ULxWpQHkilor6pkdLF7u7EiTzDbfcU= -github.com/mmcloughlin/avo v0.4.0/go.mod h1:RW9BfYA3TgO9uCdNrKU2h6J8cPD8ZLznvfgHAeszb1s= github.com/mmcloughlin/avo v0.5.0 h1:nAco9/aI9Lg2kiuROBY6BhCI/z0t5jEvJfjWbL8qXLU= github.com/mmcloughlin/avo v0.5.0/go.mod h1:ChHFdoV7ql95Wi7vuq2YT1bwCJqiWdZrQ1im3VujLYM= -github.com/yuin/goldmark v1.4.0/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k= github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY= -golang.org/x/arch v0.0.0-20210923205945-b76863e36670/go.mod h1:5om86z9Hs0C8fWVUuoMHwpExlXzs5Tkyp9hOrfG7pp8= golang.org/x/arch v0.1.0/go.mod h1:5om86z9Hs0C8fWVUuoMHwpExlXzs5Tkyp9hOrfG7pp8= golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w= -golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI= golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc= golang.org/x/crypto v0.1.0/go.mod h1:RecgLatLF4+eUMCP1PoPZQb+cVrJcOPbHkTkbkB9sbw= -golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo= -golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA= golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4= golang.org/x/mod v0.6.0/go.mod h1:4mET923SAdbXp2ki8ey+zGs1SLqsuM2Y0uvdZR/fUNI= golang.org/x/mod v0.8.0 h1:LUYupSeNrTNCGzR/hVBk2NHZO4hXcVaW1k4Qx7rjPx8= golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs= -golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg= golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s= golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg= -golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y= golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c= golang.org/x/net v0.1.0/go.mod h1:Cx3nUiGt4eDBEyega/BKRp+/AlGL8hYe7U9odMt2Cco= golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs= golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= -golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= +golang.org/x/sync v0.1.0 h1:wsuoTGHzEhffawBOhz5CYhcrV4IdKZbEyZjBMuTp12o= golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY= -golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs= golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs= -golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs= golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= -golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= -golang.org/x/sys v0.0.0-20211030160813-b3129d9d1021 h1:giLT+HuUP/gXYrG2Plg9WTjj4qhfgaW424ZIFog3rlk= -golang.org/x/sys v0.0.0-20211030160813-b3129d9d1021/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.1.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= @@ -46,22 +32,14 @@ golang.org/x/term v0.1.0/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8= golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k= golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ= golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ= -golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ= golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ= golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8= golang.org/x/text v0.7.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8= golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ= golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo= -golang.org/x/tools v0.1.7 h1:6j8CgantCy3yc8JGBqkDLMKWqZ0RDU2g1HVgacojGWQ= -golang.org/x/tools v0.1.7/go.mod h1:LGqMHiF4EqQNHR1JncWGqT5BVaXmza+X+BDGol+dOxo= golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc= golang.org/x/tools v0.2.0/go.mod h1:y4OqIKeOV/fWJetJ8bXPU1sEVniLMIyDAZWeHdV+NTA= golang.org/x/tools v0.6.0 h1:BOw41kyTf3PuCW1pVQf8+Cyg8pMlkYB1oo9iJ6D/lKM= golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU= golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= -golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= -golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE= -golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= -golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2 h1:H2TDz8ibqkAF6YGhCdN3jS9O0/s90v0rJh3X/OLHEUk= -golang.org/x/xerrors v0.0.0-20220907171357-04be3eba64a2/go.mod h1:K8+ghG5WaK9qNqU5K3HdILfMLy1f3aNYFI/wnl100a8= rsc.io/pdf v0.1.1/go.mod h1:n8OzWcQ6Sp37PL01nO98y4iUCRdTGarVfzxY20ICaU4= diff --git a/zstd/matchlen_amd64.go b/zstd/matchlen_amd64.go new file mode 100644 index 0000000000..7d51841e8f --- /dev/null +++ b/zstd/matchlen_amd64.go @@ -0,0 +1,10 @@ +//go:build amd64 && !appengine && !noasm && gc +// +build amd64,!appengine,!noasm,gc + +package zstd + +// matchLen returns the maximum common prefix length of a and b. +// a must be the shortest of the two. +// +//go:noescape +func matchLen(a, b []byte) int diff --git a/zstd/matchlen_amd64.s b/zstd/matchlen_amd64.s new file mode 100644 index 0000000000..f2ce9c7c35 --- /dev/null +++ b/zstd/matchlen_amd64.s @@ -0,0 +1,72 @@ +// Code generated by command: go run gen_matchlen.go -out ../matchlen_amd64.s -pkg=zstd. DO NOT EDIT. + +//go:build !appengine && !noasm && gc && !noasm + +#include "textflag.h" + +// func matchLen(a []byte, b []byte) int +// Requires: AVX, AVX2, BMI, CMOV +TEXT ·matchLen(SB), NOSPLIT, $0-56 + // load param + MOVQ a_base+0(FP), AX + MOVQ a_len+8(FP), CX + MOVQ b_base+24(FP), DX + XORQ SI, SI + + // find the minimum length slice +loop: + CMPQ CX, $0x20 + JB last_loop + + // load 32 bytes into YMM registers + VMOVDQU (AX), Y0 + VMOVDQU (DX), Y1 + + // compare bytes in adata and bdata, like 'bytewise XNOR' + // if the byte is the same in adata and bdata, VPCMPEQB will store 0xFF in the same position in equalMaskBytes + VPCMPEQB Y0, Y1, Y0 + + // like convert byte to bit, store equalMaskBytes into general reg + VPMOVMSKB Y0, BX + CMPL BX, $0xffffffff + JNE cal_prefix + ADDQ $0x20, AX + ADDQ $0x20, DX + SUBQ $0x20, CX + ADDQ $0x20, SI + JMP loop + +last_loop: + TESTQ CX, CX + JZ ret + VMOVDQU (AX), Y0 + VMOVDQU (DX), Y1 + VPCMPEQB Y0, Y1, Y0 + VPMOVMSKB Y0, BX + CMPL BX, $0xffffffff + JNE cal_last_prefix + + // if last bytes are all equal, just add remaining len on ret and return + ADDQ CX, SI + JMP ret + +cal_last_prefix: + NOTQ BX + + // store first not equal position into matchedLen + TZCNTQ BX, AX + + // if matched len > remaining len, just add remaining on ret + CMPQ CX, AX + CMOVQLT CX, AX + ADDQ AX, SI + JMP ret + +cal_prefix: + NOTQ BX + TZCNTQ BX, AX + ADDQ AX, SI + +ret: + MOVQ SI, ret+48(FP) + RET diff --git a/zstd/matchlen_generic.go b/zstd/matchlen_generic.go new file mode 100644 index 0000000000..40ee6f013e --- /dev/null +++ b/zstd/matchlen_generic.go @@ -0,0 +1,30 @@ +//go:build !amd64 || appengine || !gc || noasm +// +build !amd64 appengine !gc noasm + +package zstd + +import ( + "encoding/binary" + "math/bits" +) + +// matchLen returns the maximum common prefix length of a and b. +// a must be the shortest of the two. +func matchLen(a, b []byte) (n int) { + for ; len(a) >= 8 && len(b) >= 8; a, b = a[8:], b[8:] { + diff := binary.LittleEndian.Uint64(a) ^ binary.LittleEndian.Uint64(b) + if diff != 0 { + return n + bits.TrailingZeros64(diff)>>3 + } + n += 8 + } + + for i := range a { + if a[i] != b[i] { + break + } + n++ + } + return n + +} diff --git a/zstd/zstd.go b/zstd/zstd.go index 89396673d9..4be7cc7367 100644 --- a/zstd/zstd.go +++ b/zstd/zstd.go @@ -9,7 +9,6 @@ import ( "errors" "log" "math" - "math/bits" ) // enable debug printing @@ -106,27 +105,6 @@ func printf(format string, a ...interface{}) { } } -// matchLen returns the maximum common prefix length of a and b. -// a must be the shortest of the two. -func matchLen(a, b []byte) (n int) { - for ; len(a) >= 8 && len(b) >= 8; a, b = a[8:], b[8:] { - diff := binary.LittleEndian.Uint64(a) ^ binary.LittleEndian.Uint64(b) - if diff != 0 { - return n + bits.TrailingZeros64(diff)>>3 - } - n += 8 - } - - for i := range a { - if a[i] != b[i] { - break - } - n++ - } - return n - -} - func load3232(b []byte, i int32) uint32 { return binary.LittleEndian.Uint32(b[:len(b):len(b)][i:]) }