| // 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" |
| |
| #define PosInf 0x7FF0000000000000 |
| #define NegInf 0xFFF0000000000000 |
| #define NegZero 0x8000000000000000 |
| #define Pi 0x400921FB54442D18 |
| #define NegPi 0xC00921FB54442D18 |
| #define Pi3Div4 0x4002D97C7F3321D2 // 3Pi/4 |
| #define NegPi3Div4 0xC002D97C7F3321D2 // -3Pi/4 |
| #define PiDiv4 0x3FE921FB54442D18 // Pi/4 |
| #define NegPiDiv4 0xBFE921FB54442D18 // -Pi/4 |
| |
| // Minimax polynomial coefficients and other constants |
| DATA ·atan2rodataL25<> + 0(SB)/8, $0.199999999999554423E+00 |
| DATA ·atan2rodataL25<> + 8(SB)/8, $-.333333333333330928E+00 |
| DATA ·atan2rodataL25<> + 16(SB)/8, $0.111111110136634272E+00 |
| DATA ·atan2rodataL25<> + 24(SB)/8, $-.142857142828026806E+00 |
| DATA ·atan2rodataL25<> + 32(SB)/8, $0.769228118888682505E-01 |
| DATA ·atan2rodataL25<> + 40(SB)/8, $0.588059263575587687E-01 |
| DATA ·atan2rodataL25<> + 48(SB)/8, $-.909090711945939878E-01 |
| DATA ·atan2rodataL25<> + 56(SB)/8, $-.666641501287528609E-01 |
| DATA ·atan2rodataL25<> + 64(SB)/8, $0.472329433805024762E-01 |
| DATA ·atan2rodataL25<> + 72(SB)/8, $-.525380587584426406E-01 |
| DATA ·atan2rodataL25<> + 80(SB)/8, $-.422172007412067035E-01 |
| DATA ·atan2rodataL25<> + 88(SB)/8, $0.366935664549587481E-01 |
| DATA ·atan2rodataL25<> + 96(SB)/8, $0.220852012160300086E-01 |
| DATA ·atan2rodataL25<> + 104(SB)/8, $-.299856214685512712E-01 |
| DATA ·atan2rodataL25<> + 112(SB)/8, $0.726338160757602439E-02 |
| DATA ·atan2rodataL25<> + 120(SB)/8, $0.134893651284712515E-04 |
| DATA ·atan2rodataL25<> + 128(SB)/8, $-.291935324869629616E-02 |
| DATA ·atan2rodataL25<> + 136(SB)/8, $-.154797890856877418E-03 |
| DATA ·atan2rodataL25<> + 144(SB)/8, $0.843488472994227321E-03 |
| DATA ·atan2rodataL25<> + 152(SB)/8, $-.139950258898989925E-01 |
| GLOBL ·atan2rodataL25<> + 0(SB), RODATA, $160 |
| |
| DATA ·atan2xpi2h<> + 0(SB)/8, $0x3ff330e4e4fa7b1b |
| DATA ·atan2xpi2h<> + 8(SB)/8, $0xbff330e4e4fa7b1b |
| DATA ·atan2xpi2h<> + 16(SB)/8, $0x400330e4e4fa7b1b |
| DATA ·atan2xpi2h<> + 24(SB)/8, $0xc00330e4e4fa7b1b |
| GLOBL ·atan2xpi2h<> + 0(SB), RODATA, $32 |
| DATA ·atan2xpim<> + 0(SB)/8, $0x3ff4f42b00000000 |
| GLOBL ·atan2xpim<> + 0(SB), RODATA, $8 |
| |
| // Atan2 returns the arc tangent of y/x, using |
| // the signs of the two to determine the quadrant |
| // of the return value. |
| // |
| // Special cases are (in order): |
| // Atan2(y, NaN) = NaN |
| // Atan2(NaN, x) = NaN |
| // Atan2(+0, x>=0) = +0 |
| // Atan2(-0, x>=0) = -0 |
| // Atan2(+0, x<=-0) = +Pi |
| // Atan2(-0, x<=-0) = -Pi |
| // Atan2(y>0, 0) = +Pi/2 |
| // Atan2(y<0, 0) = -Pi/2 |
| // Atan2(+Inf, +Inf) = +Pi/4 |
| // Atan2(-Inf, +Inf) = -Pi/4 |
| // Atan2(+Inf, -Inf) = 3Pi/4 |
| // Atan2(-Inf, -Inf) = -3Pi/4 |
| // Atan2(y, +Inf) = 0 |
| // Atan2(y>0, -Inf) = +Pi |
| // Atan2(y<0, -Inf) = -Pi |
| // Atan2(+Inf, x) = +Pi/2 |
| // Atan2(-Inf, x) = -Pi/2 |
| // The algorithm used is minimax polynomial approximation |
| // with coefficients determined with a Remez exchange algorithm. |
| |
| TEXT ·atan2Asm(SB), NOSPLIT, $0-24 |
| // special case |
| MOVD x+0(FP), R1 |
| MOVD y+8(FP), R2 |
| |
| // special case Atan2(NaN, y) = NaN |
| MOVD $~(1<<63), R5 |
| AND R1, R5 // x = |x| |
| MOVD $PosInf, R3 |
| CMPUBLT R3, R5, returnX |
| |
| // special case Atan2(x, NaN) = NaN |
| MOVD $~(1<<63), R5 |
| AND R2, R5 |
| CMPUBLT R3, R5, returnY |
| |
| MOVD $NegZero, R3 |
| CMPUBEQ R3, R1, xIsNegZero |
| |
| MOVD $0, R3 |
| CMPUBEQ R3, R1, xIsPosZero |
| |
| MOVD $PosInf, R4 |
| CMPUBEQ R4, R2, yIsPosInf |
| |
| MOVD $NegInf, R4 |
| CMPUBEQ R4, R2, yIsNegInf |
| BR Normal |
| xIsNegZero: |
| // special case Atan(-0, y>=0) = -0 |
| MOVD $0, R4 |
| CMPBLE R4, R2, returnX |
| |
| //special case Atan2(-0, y<=-0) = -Pi |
| MOVD $NegZero, R4 |
| CMPBGE R4, R2, returnNegPi |
| BR Normal |
| xIsPosZero: |
| //special case Atan2(0, 0) = 0 |
| MOVD $0, R4 |
| CMPUBEQ R4, R2, returnX |
| |
| //special case Atan2(0, y<=-0) = Pi |
| MOVD $NegZero, R4 |
| CMPBGE R4, R2, returnPi |
| BR Normal |
| yIsNegInf: |
| //special case Atan2(+Inf, -Inf) = 3Pi/4 |
| MOVD $PosInf, R3 |
| CMPUBEQ R3, R1, posInfNegInf |
| |
| //special case Atan2(-Inf, -Inf) = -3Pi/4 |
| MOVD $NegInf, R3 |
| CMPUBEQ R3, R1, negInfNegInf |
| BR Normal |
| yIsPosInf: |
| //special case Atan2(+Inf, +Inf) = Pi/4 |
| MOVD $PosInf, R3 |
| CMPUBEQ R3, R1, posInfPosInf |
| |
| //special case Atan2(-Inf, +Inf) = -Pi/4 |
| MOVD $NegInf, R3 |
| CMPUBEQ R3, R1, negInfPosInf |
| |
| //special case Atan2(-Pi, +Inf) = Pi |
| MOVD $NegPi, R3 |
| CMPUBEQ R3, R1, negPiPosInf |
| |
| Normal: |
| FMOVD x+0(FP), F0 |
| FMOVD y+8(FP), F2 |
| MOVD $·atan2rodataL25<>+0(SB), R9 |
| LGDR F0, R2 |
| LGDR F2, R1 |
| RISBGNZ $32, $63, $32, R2, R2 |
| RISBGNZ $32, $63, $32, R1, R1 |
| WORD $0xB9170032 //llgtr %r3,%r2 |
| RISBGZ $63, $63, $33, R2, R5 |
| WORD $0xB9170041 //llgtr %r4,%r1 |
| WFLCDB V0, V20 |
| MOVW R4, R6 |
| MOVW R3, R7 |
| CMPUBLT R6, R7, L17 |
| WFDDB V2, V0, V3 |
| ADDW $2, R5, R2 |
| MOVW R4, R6 |
| MOVW R3, R7 |
| CMPUBLE R6, R7, L20 |
| L3: |
| WFMDB V3, V3, V4 |
| VLEG $0, 152(R9), V18 |
| VLEG $0, 144(R9), V16 |
| FMOVD 136(R9), F1 |
| FMOVD 128(R9), F5 |
| FMOVD 120(R9), F6 |
| WFMADB V4, V16, V5, V16 |
| WFMADB V4, V6, V1, V6 |
| FMOVD 112(R9), F7 |
| WFMDB V4, V4, V1 |
| WFMADB V4, V7, V18, V7 |
| VLEG $0, 104(R9), V18 |
| WFMADB V1, V6, V16, V6 |
| CMPWU R4, R3 |
| FMOVD 96(R9), F5 |
| VLEG $0, 88(R9), V16 |
| WFMADB V4, V5, V18, V5 |
| VLEG $0, 80(R9), V18 |
| VLEG $0, 72(R9), V22 |
| WFMADB V4, V16, V18, V16 |
| VLEG $0, 64(R9), V18 |
| WFMADB V1, V7, V5, V7 |
| WFMADB V4, V18, V22, V18 |
| WFMDB V1, V1, V5 |
| WFMADB V1, V16, V18, V16 |
| VLEG $0, 56(R9), V18 |
| WFMADB V5, V6, V7, V6 |
| VLEG $0, 48(R9), V22 |
| FMOVD 40(R9), F7 |
| WFMADB V4, V7, V18, V7 |
| VLEG $0, 32(R9), V18 |
| WFMADB V5, V6, V16, V6 |
| WFMADB V4, V18, V22, V18 |
| VLEG $0, 24(R9), V16 |
| WFMADB V1, V7, V18, V7 |
| VLEG $0, 16(R9), V18 |
| VLEG $0, 8(R9), V22 |
| WFMADB V4, V18, V16, V18 |
| VLEG $0, 0(R9), V16 |
| WFMADB V5, V6, V7, V6 |
| WFMADB V4, V16, V22, V16 |
| FMUL F3, F4 |
| WFMADB V1, V18, V16, V1 |
| FMADD F6, F5, F1 |
| WFMADB V4, V1, V3, V4 |
| BLT L18 |
| BGT L7 |
| LTDBR F2, F2 |
| BLTU L21 |
| L8: |
| LTDBR F0, F0 |
| BLTU L22 |
| L9: |
| WFCHDBS V2, V0, V0 |
| BNE L18 |
| L7: |
| MOVW R1, R6 |
| CMPBGE R6, $0, L1 |
| L18: |
| RISBGZ $58, $60, $3, R2, R2 |
| MOVD $·atan2xpi2h<>+0(SB), R1 |
| MOVD ·atan2xpim<>+0(SB), R3 |
| LDGR R3, F0 |
| WORD $0xED021000 //madb %f4,%f0,0(%r2,%r1) |
| BYTE $0x40 |
| BYTE $0x1E |
| L1: |
| FMOVD F4, ret+16(FP) |
| RET |
| |
| L20: |
| LTDBR F2, F2 |
| BLTU L23 |
| FMOVD F2, F6 |
| L4: |
| LTDBR F0, F0 |
| BLTU L24 |
| FMOVD F0, F4 |
| L5: |
| WFCHDBS V6, V4, V4 |
| BEQ L3 |
| L17: |
| WFDDB V0, V2, V4 |
| BYTE $0x18 //lr %r2,%r5 |
| BYTE $0x25 |
| WORD $0xB3130034 //lcdbr %f3,%f4 |
| BR L3 |
| L23: |
| WORD $0xB3130062 //lcdbr %f6,%f2 |
| BR L4 |
| L22: |
| VLR V20, V0 |
| BR L9 |
| L21: |
| WORD $0xB3130022 //lcdbr %f2,%f2 |
| BR L8 |
| L24: |
| VLR V20, V4 |
| BR L5 |
| returnX: //the result is same as the first argument |
| MOVD R1, ret+16(FP) |
| RET |
| returnY: //the result is same as the second argument |
| MOVD R2, ret+16(FP) |
| RET |
| returnPi: |
| MOVD $Pi, R1 |
| MOVD R1, ret+16(FP) |
| RET |
| returnNegPi: |
| MOVD $NegPi, R1 |
| MOVD R1, ret+16(FP) |
| RET |
| posInfNegInf: |
| MOVD $Pi3Div4, R1 |
| MOVD R1, ret+16(FP) |
| RET |
| negInfNegInf: |
| MOVD $NegPi3Div4, R1 |
| MOVD R1, ret+16(FP) |
| RET |
| posInfPosInf: |
| MOVD $PiDiv4, R1 |
| MOVD R1, ret+16(FP) |
| RET |
| negInfPosInf: |
| MOVD $NegPiDiv4, R1 |
| MOVD R1, ret+16(FP) |
| RET |
| negPiPosInf: |
| MOVD $NegZero, R1 |
| MOVD R1, ret+16(FP) |
| RET |
