| // Copyright 2016 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| #include "textflag.h" |
| |
| // Minimax polynomial approximations |
| DATA tanhrodataL18<>+0(SB)/8, $-1.0 |
| DATA tanhrodataL18<>+8(SB)/8, $-2.0 |
| DATA tanhrodataL18<>+16(SB)/8, $1.0 |
| DATA tanhrodataL18<>+24(SB)/8, $2.0 |
| DATA tanhrodataL18<>+32(SB)/8, $0.20000000000000011868E+01 |
| DATA tanhrodataL18<>+40(SB)/8, $0.13333333333333341256E+01 |
| DATA tanhrodataL18<>+48(SB)/8, $0.26666666663549111502E+00 |
| DATA tanhrodataL18<>+56(SB)/8, $0.66666666658721844678E+00 |
| DATA tanhrodataL18<>+64(SB)/8, $0.88890217768964374821E-01 |
| DATA tanhrodataL18<>+72(SB)/8, $0.25397199429103821138E-01 |
| DATA tanhrodataL18<>+80(SB)/8, $-.346573590279972643E+00 |
| DATA tanhrodataL18<>+88(SB)/8, $20.E0 |
| GLOBL tanhrodataL18<>+0(SB), RODATA, $96 |
| |
| // Constants |
| DATA tanhrlog2<>+0(SB)/8, $0x4007154760000000 |
| GLOBL tanhrlog2<>+0(SB), RODATA, $8 |
| DATA tanhxadd<>+0(SB)/8, $0xc2f0000100003ff0 |
| GLOBL tanhxadd<>+0(SB), RODATA, $8 |
| DATA tanhxmone<>+0(SB)/8, $-1.0 |
| GLOBL tanhxmone<>+0(SB), RODATA, $8 |
| DATA tanhxzero<>+0(SB)/8, $0 |
| GLOBL tanhxzero<>+0(SB), RODATA, $8 |
| |
| // Polynomial coefficients |
| DATA tanhtab<>+0(SB)/8, $0.000000000000000000E+00 |
| DATA tanhtab<>+8(SB)/8, $-.171540871271399150E-01 |
| DATA tanhtab<>+16(SB)/8, $-.306597931864376363E-01 |
| DATA tanhtab<>+24(SB)/8, $-.410200970469965021E-01 |
| DATA tanhtab<>+32(SB)/8, $-.486343079978231466E-01 |
| DATA tanhtab<>+40(SB)/8, $-.538226193725835820E-01 |
| DATA tanhtab<>+48(SB)/8, $-.568439602538111520E-01 |
| DATA tanhtab<>+56(SB)/8, $-.579091847395528847E-01 |
| DATA tanhtab<>+64(SB)/8, $-.571909584179366341E-01 |
| DATA tanhtab<>+72(SB)/8, $-.548312665987204407E-01 |
| DATA tanhtab<>+80(SB)/8, $-.509471843643441085E-01 |
| DATA tanhtab<>+88(SB)/8, $-.456353588448863359E-01 |
| DATA tanhtab<>+96(SB)/8, $-.389755254243262365E-01 |
| DATA tanhtab<>+104(SB)/8, $-.310332908285244231E-01 |
| DATA tanhtab<>+112(SB)/8, $-.218623539150173528E-01 |
| DATA tanhtab<>+120(SB)/8, $-.115062908917949451E-01 |
| GLOBL tanhtab<>+0(SB), RODATA, $128 |
| |
| // Tanh returns the hyperbolic tangent of the argument. |
| // |
| // Special cases are: |
| // Tanh(±0) = ±0 |
| // Tanh(±Inf) = ±1 |
| // Tanh(NaN) = NaN |
| // The algorithm used is minimax polynomial approximation using a table of |
| // polynomial coefficients determined with a Remez exchange algorithm. |
| |
| TEXT ·tanhAsm(SB),NOSPLIT,$0-16 |
| FMOVD x+0(FP), F0 |
| // special case Tanh(±0) = ±0 |
| FMOVD $(0.0), F1 |
| FCMPU F0, F1 |
| BEQ tanhIsZero |
| MOVD $tanhrodataL18<>+0(SB), R5 |
| LTDBR F0, F0 |
| MOVD $0x4034000000000000, R1 |
| BLTU L15 |
| FMOVD F0, F1 |
| L2: |
| MOVD $tanhxadd<>+0(SB), R2 |
| FMOVD 0(R2), F2 |
| MOVD tanhrlog2<>+0(SB), R2 |
| LDGR R2, F4 |
| WFMSDB V0, V4, V2, V4 |
| MOVD $tanhtab<>+0(SB), R3 |
| LGDR F4, R2 |
| WORD $0xEC4239BC //risbg %r4,%r2,57,128+60,3 |
| BYTE $0x03 |
| BYTE $0x55 |
| WORD $0xED105058 //cdb %f1,.L19-.L18(%r5) |
| BYTE $0x00 |
| BYTE $0x19 |
| WORD $0xEC12000F //risbgn %r1,%r2,64-64+0,64-64+0+16-1,64-0-16 |
| BYTE $0x30 |
| BYTE $0x59 |
| WORD $0x68543000 //ld %f5,0(%r4,%r3) |
| LDGR R1, F6 |
| BLT L3 |
| MOVD $tanhxzero<>+0(SB), R1 |
| FMOVD 0(R1), F2 |
| WFCHDBS V0, V2, V4 |
| BEQ L9 |
| WFCHDBS V2, V0, V2 |
| BNE L1 |
| MOVD $tanhxmone<>+0(SB), R1 |
| FMOVD 0(R1), F0 |
| FMOVD F0, ret+8(FP) |
| RET |
| |
| L3: |
| FADD F4, F2 |
| FMOVD tanhrodataL18<>+80(SB), F4 |
| FMADD F4, F2, F0 |
| FMOVD tanhrodataL18<>+72(SB), F1 |
| WFMDB V0, V0, V3 |
| FMOVD tanhrodataL18<>+64(SB), F2 |
| WFMADB V0, V1, V2, V1 |
| FMOVD tanhrodataL18<>+56(SB), F4 |
| FMOVD tanhrodataL18<>+48(SB), F2 |
| WFMADB V1, V3, V4, V1 |
| FMOVD tanhrodataL18<>+40(SB), F4 |
| WFMADB V3, V2, V4, V2 |
| FMOVD tanhrodataL18<>+32(SB), F4 |
| WORD $0xB9270022 //lhr %r2,%r2 |
| WFMADB V3, V1, V4, V1 |
| FMOVD tanhrodataL18<>+24(SB), F4 |
| WFMADB V3, V2, V4, V3 |
| WFMADB V0, V5, V0, V2 |
| WFMADB V0, V1, V3, V0 |
| WORD $0xA7183ECF //lhi %r1,16079 |
| WFMADB V0, V2, V5, V2 |
| FMUL F6, F2 |
| MOVW R2, R10 |
| MOVW R1, R11 |
| CMPBLE R10, R11, L16 |
| FMOVD F6, F0 |
| WORD $0xED005010 //adb %f0,.L28-.L18(%r5) |
| BYTE $0x00 |
| BYTE $0x1A |
| WORD $0xA7184330 //lhi %r1,17200 |
| FADD F2, F0 |
| MOVW R2, R10 |
| MOVW R1, R11 |
| CMPBGT R10, R11, L17 |
| WORD $0xED605010 //sdb %f6,.L28-.L18(%r5) |
| BYTE $0x00 |
| BYTE $0x1B |
| FADD F6, F2 |
| WFDDB V0, V2, V0 |
| FMOVD F0, ret+8(FP) |
| RET |
| |
| L9: |
| FMOVD tanhrodataL18<>+16(SB), F0 |
| L1: |
| FMOVD F0, ret+8(FP) |
| RET |
| |
| L15: |
| FNEG F0, F1 |
| BR L2 |
| L16: |
| FADD F6, F2 |
| FMOVD tanhrodataL18<>+8(SB), F0 |
| FMADD F4, F2, F0 |
| FMOVD tanhrodataL18<>+0(SB), F4 |
| FNEG F0, F0 |
| WFMADB V0, V2, V4, V0 |
| FMOVD F0, ret+8(FP) |
| RET |
| |
| L17: |
| WFDDB V0, V4, V0 |
| FMOVD tanhrodataL18<>+16(SB), F2 |
| WFSDB V0, V2, V0 |
| FMOVD F0, ret+8(FP) |
| RET |
| |
| tanhIsZero: //return ±0 |
| FMOVD F0, ret+8(FP) |
| RET |
