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// 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 ·atanhrodataL10<> + 0(SB)/8, $.41375273347623353626
DATA ·atanhrodataL10<> + 8(SB)/8, $.51487302528619766235E+04
DATA ·atanhrodataL10<> + 16(SB)/8, $-1.67526912689208984375
DATA ·atanhrodataL10<> + 24(SB)/8, $0.181818181818181826E+00
DATA ·atanhrodataL10<> + 32(SB)/8, $-.165289256198351540E-01
DATA ·atanhrodataL10<> + 40(SB)/8, $0.200350613573012186E-02
DATA ·atanhrodataL10<> + 48(SB)/8, $0.397389654305194527E-04
DATA ·atanhrodataL10<> + 56(SB)/8, $-.273205381970859341E-03
DATA ·atanhrodataL10<> + 64(SB)/8, $0.938370938292558173E-06
DATA ·atanhrodataL10<> + 72(SB)/8, $-.148682720127920854E-06
DATA ·atanhrodataL10<> + 80(SB)/8, $ 0.212881813645679599E-07
DATA ·atanhrodataL10<> + 88(SB)/8, $-.602107458843052029E-05
DATA ·atanhrodataL10<> + 96(SB)/8, $-5.5
DATA ·atanhrodataL10<> + 104(SB)/8, $-0.5
DATA ·atanhrodataL10<> + 112(SB)/8, $0.0
DATA ·atanhrodataL10<> + 120(SB)/8, $0x7ff8000000000000 //Nan
DATA ·atanhrodataL10<> + 128(SB)/8, $-1.0
DATA ·atanhrodataL10<> + 136(SB)/8, $1.0
DATA ·atanhrodataL10<> + 144(SB)/8, $1.0E-20
GLOBL ·atanhrodataL10<> + 0(SB), RODATA, $152
// Table of log correction terms
DATA ·atanhtab2076<> + 0(SB)/8, $0.585235384085551248E-01
DATA ·atanhtab2076<> + 8(SB)/8, $0.412206153771168640E-01
DATA ·atanhtab2076<> + 16(SB)/8, $0.273839003221648339E-01
DATA ·atanhtab2076<> + 24(SB)/8, $0.166383778368856480E-01
DATA ·atanhtab2076<> + 32(SB)/8, $0.866678223433169637E-02
DATA ·atanhtab2076<> + 40(SB)/8, $0.319831684989627514E-02
DATA ·atanhtab2076<> + 48(SB)/8, $0.000000000000000000E+00
DATA ·atanhtab2076<> + 56(SB)/8, $-.113006378583725549E-02
DATA ·atanhtab2076<> + 64(SB)/8, $-.367979419636602491E-03
DATA ·atanhtab2076<> + 72(SB)/8, $0.213172484510484979E-02
DATA ·atanhtab2076<> + 80(SB)/8, $0.623271047682013536E-02
DATA ·atanhtab2076<> + 88(SB)/8, $0.118140812789696885E-01
DATA ·atanhtab2076<> + 96(SB)/8, $0.187681358930914206E-01
DATA ·atanhtab2076<> + 104(SB)/8, $0.269985148668178992E-01
DATA ·atanhtab2076<> + 112(SB)/8, $0.364186619761331328E-01
DATA ·atanhtab2076<> + 120(SB)/8, $0.469505379381388441E-01
GLOBL ·atanhtab2076<> + 0(SB), RODATA, $128
// Table of +/- .5
DATA ·atanhtabh2075<> + 0(SB)/8, $0.5
DATA ·atanhtabh2075<> + 8(SB)/8, $-.5
GLOBL ·atanhtabh2075<> + 0(SB), RODATA, $16
// Atanh returns the inverse hyperbolic tangent of the argument.
//
// Special cases are:
// Atanh(1) = +Inf
// Atanh(±0) = ±0
// Atanh(-1) = -Inf
// Atanh(x) = NaN if x < -1 or x > 1
// Atanh(NaN) = NaN
// The algorithm used is minimax polynomial approximation
// with coefficients determined with a Remez exchange algorithm.
TEXT ·atanhAsm(SB), NOSPLIT, $0-16
FMOVD x+0(FP), F0
MOVD $·atanhrodataL10<>+0(SB), R5
LGDR F0, R1
WORD $0xC0393FEF //iilf %r3,1072693247
BYTE $0xFF
BYTE $0xFF
SRAD $32, R1
WORD $0xB9170021 //llgtr %r2,%r1
MOVW R2, R6
MOVW R3, R7
CMPBGT R6, R7, L2
WORD $0xC0392FFF //iilf %r3,805306367
BYTE $0xFF
BYTE $0xFF
MOVW R2, R6
MOVW R3, R7
CMPBGT R6, R7, L9
L3:
FMOVD 144(R5), F2
FMADD F2, F0, F0
L1:
FMOVD F0, ret+8(FP)
RET
L2:
WORD $0xED005088 //cdb %f0,.L12-.L10(%r5)
BYTE $0x00
BYTE $0x19
BEQ L5
WORD $0xED005080 //cdb %f0,.L13-.L10(%r5)
BYTE $0x00
BYTE $0x19
BEQ L5
WFCEDBS V0, V0, V2
BVS L1
FMOVD 120(R5), F0
BR L1
L5:
WORD $0xED005070 //ddb %f0,.L15-.L10(%r5)
BYTE $0x00
BYTE $0x1D
FMOVD F0, ret+8(FP)
RET
L9:
FMOVD F0, F2
MOVD $·atanhtabh2075<>+0(SB), R2
SRW $31, R1, R1
FMOVD 104(R5), F4
MOVW R1, R1
SLD $3, R1, R1
WORD $0x68012000 //ld %f0,0(%r1,%r2)
WFMADB V2, V4, V0, V4
VLEG $0, 96(R5), V16
FDIV F4, F2
WORD $0xC0298006 //iilf %r2,2147909631
BYTE $0x7F
BYTE $0xFF
FMOVD 88(R5), F6
FMOVD 80(R5), F1
FMOVD 72(R5), F7
FMOVD 64(R5), F5
FMOVD F2, F4
WORD $0xED405088 //adb %f4,.L12-.L10(%r5)
BYTE $0x00
BYTE $0x1A
LGDR F4, R4
SRAD $32, R4
FMOVD F4, F3
WORD $0xED305088 //sdb %f3,.L12-.L10(%r5)
BYTE $0x00
BYTE $0x1B
SUBW R4, R2
WFSDB V3, V2, V3
RISBGZ $32, $47, $0, R2, R1
SLD $32, R1, R1
LDGR R1, F2
WFMADB V4, V2, V16, V4
SRAW $8, R2, R1
WFMADB V4, V5, V6, V5
WFMDB V4, V4, V6
WFMADB V4, V1, V7, V1
WFMADB V2, V3, V4, V2
WFMADB V1, V6, V5, V1
FMOVD 56(R5), F3
FMOVD 48(R5), F5
WFMADB V4, V5, V3, V4
FMOVD 40(R5), F3
FMADD F1, F6, F4
FMOVD 32(R5), F1
FMADD F3, F2, F1
ANDW $0xFFFFFF00, R1
WFMADB V6, V4, V1, V6
FMOVD 24(R5), F3
ORW $0x45000000, R1
WFMADB V2, V6, V3, V6
VLVGF $0, R1, V4
LDEBR F4, F4
RISBGZ $57, $60, $51, R2, R2
MOVD $·atanhtab2076<>+0(SB), R1
FMOVD 16(R5), F3
WORD $0x68521000 //ld %f5,0(%r2,%r1)
FMOVD 8(R5), F1
WFMADB V2, V6, V5, V2
WFMADB V4, V3, V1, V4
FMOVD 0(R5), F6
FMADD F6, F4, F2
FMUL F2, F0
FMOVD F0, ret+8(FP)
RET
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