| // Copyright 2017 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 coefficients and other constants |
| DATA ·atanrodataL8<> + 0(SB)/8, $0.199999999999554423E+00 |
| DATA ·atanrodataL8<> + 8(SB)/8, $0.111111110136634272E+00 |
| DATA ·atanrodataL8<> + 16(SB)/8, $-.142857142828026806E+00 |
| DATA ·atanrodataL8<> + 24(SB)/8, $-.333333333333330928E+00 |
| DATA ·atanrodataL8<> + 32(SB)/8, $0.769228118888682505E-01 |
| DATA ·atanrodataL8<> + 40(SB)/8, $0.588059263575587687E-01 |
| DATA ·atanrodataL8<> + 48(SB)/8, $-.666641501287528609E-01 |
| DATA ·atanrodataL8<> + 56(SB)/8, $-.909090711945939878E-01 |
| DATA ·atanrodataL8<> + 64(SB)/8, $0.472329433805024762E-01 |
| DATA ·atanrodataL8<> + 72(SB)/8, $0.366935664549587481E-01 |
| DATA ·atanrodataL8<> + 80(SB)/8, $-.422172007412067035E-01 |
| DATA ·atanrodataL8<> + 88(SB)/8, $-.299856214685512712E-01 |
| DATA ·atanrodataL8<> + 96(SB)/8, $0.220852012160300086E-01 |
| DATA ·atanrodataL8<> + 104(SB)/8, $0.726338160757602439E-02 |
| DATA ·atanrodataL8<> + 112(SB)/8, $0.843488472994227321E-03 |
| DATA ·atanrodataL8<> + 120(SB)/8, $0.134893651284712515E-04 |
| DATA ·atanrodataL8<> + 128(SB)/8, $-.525380587584426406E-01 |
| DATA ·atanrodataL8<> + 136(SB)/8, $-.139950258898989925E-01 |
| DATA ·atanrodataL8<> + 144(SB)/8, $-.291935324869629616E-02 |
| DATA ·atanrodataL8<> + 152(SB)/8, $-.154797890856877418E-03 |
| GLOBL ·atanrodataL8<> + 0(SB), RODATA, $160 |
| |
| DATA ·atanxpi2h<> + 0(SB)/8, $0x3ff330e4e4fa7b1b |
| DATA ·atanxpi2h<> + 8(SB)/8, $0xbff330e4e4fa7b1b |
| DATA ·atanxpi2h<> + 16(SB)/8, $0x400330e4e4fa7b1b |
| DATA ·atanxpi2h<> + 24(SB)/4, $0xc00330e4e4fa7b1b |
| GLOBL ·atanxpi2h<> + 0(SB), RODATA, $32 |
| DATA ·atanxpim<> + 0(SB)/8, $0x3ff4f42b00000000 |
| GLOBL ·atanxpim<> + 0(SB), RODATA, $8 |
| DATA ·atanxmone<> + 0(SB)/8, $-1.0 |
| GLOBL ·atanxmone<> + 0(SB), RODATA, $8 |
| |
| // Atan returns the arctangent, in radians, of the argument. |
| // |
| // Special cases are: |
| // Atan(±0) = ±0 |
| // Atan(±Inf) = ±Pi/2Pi |
| // The algorithm used is minimax polynomial approximation |
| // with coefficients determined with a Remez exchange algorithm. |
| |
| TEXT ·atanAsm(SB), NOSPLIT, $0-16 |
| FMOVD x+0(FP), F0 |
| //special case Atan(±0) = ±0 |
| FMOVD $(0.0), F1 |
| FCMPU F0, F1 |
| BEQ atanIsZero |
| |
| MOVD $·atanrodataL8<>+0(SB), R5 |
| MOVH $0x3FE0, R3 |
| WORD $0xB3CD0010 //lgdr %r1,%f0 |
| WORD $0xEC1120BF //risbgn %r1,%r1,64-32,128+63,64+0+32 |
| BYTE $0x60 |
| BYTE $0x59 |
| RLL $16, R1, R2 |
| ANDW $0x7FF0, R2 |
| MOVW R2, R6 |
| MOVW R3, R7 |
| CMPUBLE R6, R7, L6 |
| MOVD $·atanxmone<>+0(SB), R3 |
| FMOVD 0(R3), F2 |
| WFDDB V0, V2, V0 |
| WORD $0xEC113FBF //risbg %r1,%r1,64-1,128+63,64+32+1 |
| BYTE $0x61 |
| BYTE $0x55 |
| MOVD $·atanxpi2h<>+0(SB), R3 |
| MOVWZ R1, R1 |
| SLD $3, R1, R1 |
| WORD $0x68813000 //ld %f8,0(%r1,%r3) |
| L6: |
| WFMDB V0, V0, V2 |
| FMOVD 152(R5), F6 |
| FMOVD 144(R5), F1 |
| FMOVD 136(R5), F7 |
| VLEG $0, 128(R5), V16 |
| FMOVD 120(R5), F4 |
| FMOVD 112(R5), F5 |
| WFMADB V2, V4, V6, V4 |
| WFMADB V2, V5, V1, V5 |
| WFMDB V2, V2, V6 |
| FMOVD 104(R5), F3 |
| FMOVD 96(R5), F1 |
| WFMADB V2, V3, V7, V3 |
| MOVH $0x3FE0, R1 |
| FMOVD 88(R5), F7 |
| WFMADB V2, V1, V7, V1 |
| FMOVD 80(R5), F7 |
| WFMADB V6, V3, V1, V3 |
| WFMADB V6, V4, V5, V4 |
| WFMDB V6, V6, V1 |
| FMOVD 72(R5), F5 |
| WFMADB V2, V5, V7, V5 |
| FMOVD 64(R5), F7 |
| WFMADB V2, V7, V16, V7 |
| VLEG $0, 56(R5), V16 |
| WFMADB V6, V5, V7, V5 |
| WFMADB V1, V4, V3, V4 |
| FMOVD 48(R5), F7 |
| FMOVD 40(R5), F3 |
| WFMADB V2, V3, V7, V3 |
| FMOVD 32(R5), F7 |
| WFMADB V2, V7, V16, V7 |
| VLEG $0, 24(R5), V16 |
| WFMADB V1, V4, V5, V4 |
| FMOVD 16(R5), F5 |
| WFMADB V6, V3, V7, V3 |
| FMOVD 8(R5), F7 |
| WFMADB V2, V7, V5, V7 |
| FMOVD 0(R5), F5 |
| WFMADB V2, V5, V16, V5 |
| WFMADB V1, V4, V3, V4 |
| WFMADB V6, V7, V5, V6 |
| FMUL F0, F2 |
| FMADD F4, F1, F6 |
| FMADD F6, F2, F0 |
| MOVW R2, R6 |
| MOVW R1, R7 |
| CMPUBLE R6, R7, L1 |
| MOVD $·atanxpim<>+0(SB), R1 |
| WORD $0xED801000 //madb %f0,%f8,0(%r1) |
| BYTE $0x00 |
| BYTE $0x1E |
| L1: |
| atanIsZero: |
| FMOVD F0, ret+8(FP) |
| RET |
