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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 approximations
+DATA ·tanrodataL13<> + 0(SB)/8, $0.181017336383229927e-07
+DATA ·tanrodataL13<> + 8(SB)/8, $-.256590857271311164e-03
+DATA ·tanrodataL13<> + 16(SB)/8, $-.464359274328689195e+00
+DATA ·tanrodataL13<> + 24(SB)/8, $1.0
+DATA ·tanrodataL13<> + 32(SB)/8, $-.333333333333333464e+00
+DATA ·tanrodataL13<> + 40(SB)/8, $0.245751217306830032e-01
+DATA ·tanrodataL13<> + 48(SB)/8, $-.245391301343844510e-03
+DATA ·tanrodataL13<> + 56(SB)/8, $0.214530914428992319e-01
+DATA ·tanrodataL13<> + 64(SB)/8, $0.108285667160535624e-31
+DATA ·tanrodataL13<> + 72(SB)/8, $0.612323399573676480e-16
+DATA ·tanrodataL13<> + 80(SB)/8, $0.157079632679489656e+01
+DATA ·tanrodataL13<> + 88(SB)/8, $0.636619772367581341e+00
+GLOBL ·tanrodataL13<> + 0(SB), RODATA, $96
+
+// Constants
+DATA ·tanxnan<> + 0(SB)/8, $0x7ff8000000000000
+GLOBL ·tanxnan<> + 0(SB), RODATA, $8
+DATA ·tanxlim<> + 0(SB)/8, $0x432921fb54442d19
+GLOBL ·tanxlim<> + 0(SB), RODATA, $8
+DATA ·tanxadd<> + 0(SB)/8, $0xc338000000000000
+GLOBL ·tanxadd<> + 0(SB), RODATA, $8
+
+// Tan returns the tangent of the radian argument.
+//
+// Special cases are:
+// Tan(±0) = ±0
+// Tan(±Inf) = NaN
+// Tan(NaN) = NaN
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·tanAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ //specail case Tan(±0) = ±0
+ FMOVD $(0.0), F1
+ FCMPU F0, F1
+ BEQ atanIsZero
+
+ MOVD $·tanrodataL13<>+0(SB), R5
+ LTDBR F0, F0
+ BLTU L10
+ FMOVD F0, F2
+L2:
+ MOVD $·tanxlim<>+0(SB), R1
+ WORD $0xED201000 //cdb %f2,0(%r1)
+ BYTE $0x00
+ BYTE $0x19
+ BGE L11
+ BVS L11
+ MOVD $·tanxadd<>+0(SB), R1
+ FMOVD 88(R5), F6
+ FMOVD 0(R1), F4
+ WFMSDB V0, V6, V4, V6
+ FMOVD 80(R5), F1
+ FADD F6, F4
+ FMOVD 72(R5), F2
+ FMSUB F1, F4, F0
+ FMOVD 64(R5), F3
+ WFMADB V4, V2, V0, V2
+ FMOVD 56(R5), F1
+ WFMADB V4, V3, V2, V4
+ FMUL F2, F2
+ VLEG $0, 48(R5), V18
+ LGDR F6, R1
+ FMOVD 40(R5), F5
+ FMOVD 32(R5), F3
+ FMADD F1, F2, F3
+ FMOVD 24(R5), F1
+ FMOVD 16(R5), F7
+ FMOVD 8(R5), F0
+ WFMADB V2, V7, V1, V7
+ WFMADB V2, V0, V5, V0
+ WFMDB V2, V2, V1
+ FMOVD 0(R5), F5
+ WFLCDB V4, V16
+ WFMADB V2, V5, V18, V5
+ WFMADB V1, V0, V7, V0
+ TMLL R1, $1
+ WFMADB V1, V5, V3, V1
+ BNE L12
+ WFDDB V0, V1, V0
+ WFMDB V2, V16, V2
+ WFMADB V2, V0, V4, V0
+ WORD $0xB3130000 //lcdbr %f0,%f0
+ FMOVD F0, ret+8(FP)
+ RET
+L12:
+ WFMSDB V2, V1, V0, V2
+ WFMDB V16, V2, V2
+ FDIV F2, F0
+ FMOVD F0, ret+8(FP)
+ RET
+L11:
+ MOVD $·tanxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L10:
+ WORD $0xB3130020 //lcdbr %f2,%f0
+ BR L2
+atanIsZero:
+ FMOVD F0, ret+8(FP)
+ RET