github.com/likebike/go--@v0.0.0-20190911215757-0bd925d16e96/go/src/math/tanh_s390x.s (about) 1 // Copyright 2016 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 #include "textflag.h" 6 7 // Minimax polynomial approximations 8 DATA tanhrodataL18<>+0(SB)/8, $-1.0 9 DATA tanhrodataL18<>+8(SB)/8, $-2.0 10 DATA tanhrodataL18<>+16(SB)/8, $1.0 11 DATA tanhrodataL18<>+24(SB)/8, $2.0 12 DATA tanhrodataL18<>+32(SB)/8, $0.20000000000000011868E+01 13 DATA tanhrodataL18<>+40(SB)/8, $0.13333333333333341256E+01 14 DATA tanhrodataL18<>+48(SB)/8, $0.26666666663549111502E+00 15 DATA tanhrodataL18<>+56(SB)/8, $0.66666666658721844678E+00 16 DATA tanhrodataL18<>+64(SB)/8, $0.88890217768964374821E-01 17 DATA tanhrodataL18<>+72(SB)/8, $0.25397199429103821138E-01 18 DATA tanhrodataL18<>+80(SB)/8, $-.346573590279972643E+00 19 DATA tanhrodataL18<>+88(SB)/8, $20.E0 20 GLOBL tanhrodataL18<>+0(SB), RODATA, $96 21 22 // Constants 23 DATA tanhrlog2<>+0(SB)/8, $0x4007154760000000 24 GLOBL tanhrlog2<>+0(SB), RODATA, $8 25 DATA tanhxadd<>+0(SB)/8, $0xc2f0000100003ff0 26 GLOBL tanhxadd<>+0(SB), RODATA, $8 27 DATA tanhxmone<>+0(SB)/8, $-1.0 28 GLOBL tanhxmone<>+0(SB), RODATA, $8 29 DATA tanhxzero<>+0(SB)/8, $0 30 GLOBL tanhxzero<>+0(SB), RODATA, $8 31 32 // Polynomial coefficients 33 DATA tanhtab<>+0(SB)/8, $0.000000000000000000E+00 34 DATA tanhtab<>+8(SB)/8, $-.171540871271399150E-01 35 DATA tanhtab<>+16(SB)/8, $-.306597931864376363E-01 36 DATA tanhtab<>+24(SB)/8, $-.410200970469965021E-01 37 DATA tanhtab<>+32(SB)/8, $-.486343079978231466E-01 38 DATA tanhtab<>+40(SB)/8, $-.538226193725835820E-01 39 DATA tanhtab<>+48(SB)/8, $-.568439602538111520E-01 40 DATA tanhtab<>+56(SB)/8, $-.579091847395528847E-01 41 DATA tanhtab<>+64(SB)/8, $-.571909584179366341E-01 42 DATA tanhtab<>+72(SB)/8, $-.548312665987204407E-01 43 DATA tanhtab<>+80(SB)/8, $-.509471843643441085E-01 44 DATA tanhtab<>+88(SB)/8, $-.456353588448863359E-01 45 DATA tanhtab<>+96(SB)/8, $-.389755254243262365E-01 46 DATA tanhtab<>+104(SB)/8, $-.310332908285244231E-01 47 DATA tanhtab<>+112(SB)/8, $-.218623539150173528E-01 48 DATA tanhtab<>+120(SB)/8, $-.115062908917949451E-01 49 GLOBL tanhtab<>+0(SB), RODATA, $128 50 51 // Tanh returns the hyperbolic tangent of the argument. 52 // 53 // Special cases are: 54 // Tanh(±0) = ±0 55 // Tanh(±Inf) = ±1 56 // Tanh(NaN) = NaN 57 // The algorithm used is minimax polynomial approximation using a table of 58 // polynomial coefficients determined with a Remez exchange algorithm. 59 60 TEXT ·tanhAsm(SB),NOSPLIT,$0-16 61 FMOVD x+0(FP), F0 62 // special case Tanh(±0) = ±0 63 FMOVD $(0.0), F1 64 FCMPU F0, F1 65 BEQ tanhIsZero 66 MOVD $tanhrodataL18<>+0(SB), R5 67 WORD $0xB3120000 //ltdbr %f0,%f0 68 MOVD $0x4034000000000000, R1 69 BLTU L15 70 FMOVD F0, F1 71 L2: 72 MOVD $tanhxadd<>+0(SB), R2 73 FMOVD 0(R2), F2 74 MOVD tanhrlog2<>+0(SB), R2 75 LDGR R2, F4 76 WFMSDB V0, V4, V2, V4 77 MOVD $tanhtab<>+0(SB), R3 78 LGDR F4, R2 79 WORD $0xEC4239BC //risbg %r4,%r2,57,128+60,3 80 BYTE $0x03 81 BYTE $0x55 82 WORD $0xED105058 //cdb %f1,.L19-.L18(%r5) 83 BYTE $0x00 84 BYTE $0x19 85 WORD $0xEC12000F //risbgn %r1,%r2,64-64+0,64-64+0+16-1,64-0-16 86 BYTE $0x30 87 BYTE $0x59 88 WORD $0x68543000 //ld %f5,0(%r4,%r3) 89 LDGR R1, F6 90 BLT L3 91 MOVD $tanhxzero<>+0(SB), R1 92 FMOVD 0(R1), F2 93 WFCHDBS V0, V2, V4 94 BEQ L9 95 WFCHDBS V2, V0, V2 96 BNE L1 97 MOVD $tanhxmone<>+0(SB), R1 98 FMOVD 0(R1), F0 99 FMOVD F0, ret+8(FP) 100 RET 101 102 L3: 103 FADD F4, F2 104 FMOVD tanhrodataL18<>+80(SB), F4 105 FMADD F4, F2, F0 106 FMOVD tanhrodataL18<>+72(SB), F1 107 WFMDB V0, V0, V3 108 FMOVD tanhrodataL18<>+64(SB), F2 109 WFMADB V0, V1, V2, V1 110 FMOVD tanhrodataL18<>+56(SB), F4 111 FMOVD tanhrodataL18<>+48(SB), F2 112 WFMADB V1, V3, V4, V1 113 FMOVD tanhrodataL18<>+40(SB), F4 114 WFMADB V3, V2, V4, V2 115 FMOVD tanhrodataL18<>+32(SB), F4 116 WORD $0xB9270022 //lhr %r2,%r2 117 WFMADB V3, V1, V4, V1 118 FMOVD tanhrodataL18<>+24(SB), F4 119 WFMADB V3, V2, V4, V3 120 WFMADB V0, V5, V0, V2 121 WFMADB V0, V1, V3, V0 122 WORD $0xA7183ECF //lhi %r1,16079 123 WFMADB V0, V2, V5, V2 124 FMUL F6, F2 125 MOVW R2, R10 126 MOVW R1, R11 127 CMPBLE R10, R11, L16 128 FMOVD F6, F0 129 WORD $0xED005010 //adb %f0,.L28-.L18(%r5) 130 BYTE $0x00 131 BYTE $0x1A 132 WORD $0xA7184330 //lhi %r1,17200 133 FADD F2, F0 134 MOVW R2, R10 135 MOVW R1, R11 136 CMPBGT R10, R11, L17 137 WORD $0xED605010 //sdb %f6,.L28-.L18(%r5) 138 BYTE $0x00 139 BYTE $0x1B 140 FADD F6, F2 141 WFDDB V0, V2, V0 142 FMOVD F0, ret+8(FP) 143 RET 144 145 L9: 146 FMOVD tanhrodataL18<>+16(SB), F0 147 L1: 148 FMOVD F0, ret+8(FP) 149 RET 150 151 L15: 152 FNEG F0, F1 153 BR L2 154 L16: 155 FADD F6, F2 156 FMOVD tanhrodataL18<>+8(SB), F0 157 FMADD F4, F2, F0 158 FMOVD tanhrodataL18<>+0(SB), F4 159 FNEG F0, F0 160 WFMADB V0, V2, V4, V0 161 FMOVD F0, ret+8(FP) 162 RET 163 164 L17: 165 WFDDB V0, V4, V0 166 FMOVD tanhrodataL18<>+16(SB), F2 167 WFSDB V0, V2, V0 168 FMOVD F0, ret+8(FP) 169 RET 170 171 tanhIsZero: //return ±0 172 FMOVD F0, ret+8(FP) 173 RET