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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 ·logrodataL21<> + 0(SB)/8, $-.499999999999999778E+00
+DATA ·logrodataL21<> + 8(SB)/8, $0.333333333333343751E+00
+DATA ·logrodataL21<> + 16(SB)/8, $-.250000000001606881E+00
+DATA ·logrodataL21<> + 24(SB)/8, $0.199999999971603032E+00
+DATA ·logrodataL21<> + 32(SB)/8, $-.166666663114122038E+00
+DATA ·logrodataL21<> + 40(SB)/8, $-.125002923782692399E+00
+DATA ·logrodataL21<> + 48(SB)/8, $0.111142014580396256E+00
+DATA ·logrodataL21<> + 56(SB)/8, $0.759438932618934220E-01
+DATA ·logrodataL21<> + 64(SB)/8, $0.142857144267212549E+00
+DATA ·logrodataL21<> + 72(SB)/8, $-.993038938793590759E-01
+DATA ·logrodataL21<> + 80(SB)/8, $-1.0
+GLOBL ·logrodataL21<> + 0(SB), RODATA, $88
+
+// Constants
+DATA ·logxminf<> + 0(SB)/8, $0xfff0000000000000
+GLOBL ·logxminf<> + 0(SB), RODATA, $8
+DATA ·logxnan<> + 0(SB)/8, $0x7ff8000000000000
+GLOBL ·logxnan<> + 0(SB), RODATA, $8
+DATA ·logx43f<> + 0(SB)/8, $0x43f0000000000000
+GLOBL ·logx43f<> + 0(SB), RODATA, $8
+DATA ·logxl2<> + 0(SB)/8, $0x3fda7aecbeba4e46
+GLOBL ·logxl2<> + 0(SB), RODATA, $8
+DATA ·logxl1<> + 0(SB)/8, $0x3ffacde700000000
+GLOBL ·logxl1<> + 0(SB), RODATA, $8
+
+/* Input transform scale and add constants */
+DATA ·logxm<> + 0(SB)/8, $0x3fc77604e63c84b1
+DATA ·logxm<> + 8(SB)/8, $0x40fb39456ab53250
+DATA ·logxm<> + 16(SB)/8, $0x3fc9ee358b945f3f
+DATA ·logxm<> + 24(SB)/8, $0x40fb39418bf3b137
+DATA ·logxm<> + 32(SB)/8, $0x3fccfb2e1304f4b6
+DATA ·logxm<> + 40(SB)/8, $0x40fb393d3eda3022
+DATA ·logxm<> + 48(SB)/8, $0x3fd0000000000000
+DATA ·logxm<> + 56(SB)/8, $0x40fb393969e70000
+DATA ·logxm<> + 64(SB)/8, $0x3fd11117aafbfe04
+DATA ·logxm<> + 72(SB)/8, $0x40fb3936eaefafcf
+DATA ·logxm<> + 80(SB)/8, $0x3fd2492af5e658b2
+DATA ·logxm<> + 88(SB)/8, $0x40fb39343ff01715
+DATA ·logxm<> + 96(SB)/8, $0x3fd3b50c622a43dd
+DATA ·logxm<> + 104(SB)/8, $0x40fb39315adae2f3
+DATA ·logxm<> + 112(SB)/8, $0x3fd56bbeea918777
+DATA ·logxm<> + 120(SB)/8, $0x40fb392e21698552
+GLOBL ·logxm<> + 0(SB), RODATA, $128
+
+// Log returns the natural logarithm of the argument.
+//
+// Special cases are:
+// Log(+Inf) = +Inf
+// Log(0) = -Inf
+// Log(x < 0) = NaN
+// Log(NaN) = NaN
+// The algorithm used is minimax polynomial approximation using a table of
+// polynomial coefficients determined with a Remez exchange algorithm.
+
+TEXT ·logAsm(SB), NOSPLIT, $0-16
+ FMOVD x+0(FP), F0
+ MOVD $·logrodataL21<>+0(SB), R9
+ MOVH $0x8006, R4
+ LGDR F0, R1
+ MOVD $0x3FF0000000000000, R6
+ SRAD $48, R1, R1
+ MOVD $0x40F03E8000000000, R8
+ SUBW R1, R4
+ RISBGZ $32, $59, $0, R4, R2
+ RISBGN $0, $15, $48, R2, R6
+ RISBGN $16, $31, $32, R2, R8
+ MOVW R1, R7
+ CMPBGT R7, $22, L17
+ LTDBR F0, F0
+ MOVD $·logx43f<>+0(SB), R1
+ FMOVD 0(R1), F2
+ BLEU L3
+ MOVH $0x8005, R12
+ MOVH $0x8405, R0
+ BR L15
+L7:
+ LTDBR F0, F0
+ BLEU L3
+L15:
+ FMUL F2, F0
+ LGDR F0, R1
+ SRAD $48, R1, R1
+ SUBW R1, R0, R2
+ SUBW R1, R12, R3
+ BYTE $0x18 //lr %r4,%r2
+ BYTE $0x42
+ ANDW $0xFFFFFFF0, R3
+ ANDW $0xFFFFFFF0, R2
+ BYTE $0x18 //lr %r5,%r1
+ BYTE $0x51
+ MOVW R1, R7
+ CMPBLE R7, $22, L7
+ RISBGN $0, $15, $48, R3, R6
+ RISBGN $16, $31, $32, R2, R8
+L2:
+ MOVH R5, R5
+ MOVH $0x7FEF, R1
+ CMPW R5, R1
+ BGT L1
+ LDGR R6, F2
+ FMUL F2, F0
+ RISBGZ $57, $59, $3, R4, R4
+ FMOVD 80(R9), F2
+ MOVD $·logxm<>+0(SB), R7
+ ADD R7, R4
+ FMOVD 72(R9), F4
+ WORD $0xED004000 //madb %f2,%f0,0(%r4)
+ BYTE $0x20
+ BYTE $0x1E
+ FMOVD 64(R9), F1
+ FMOVD F2, F0
+ FMOVD 56(R9), F2
+ WFMADB V0, V2, V4, V2
+ WFMDB V0, V0, V6
+ FMOVD 48(R9), F4
+ WFMADB V0, V2, V4, V2
+ FMOVD 40(R9), F4
+ WFMADB V2, V6, V1, V2
+ FMOVD 32(R9), F1
+ WFMADB V6, V4, V1, V4
+ FMOVD 24(R9), F1
+ WFMADB V6, V2, V1, V2
+ FMOVD 16(R9), F1
+ WFMADB V6, V4, V1, V4
+ MOVD $·logxl1<>+0(SB), R1
+ FMOVD 8(R9), F1
+ WFMADB V6, V2, V1, V2
+ FMOVD 0(R9), F1
+ WFMADB V6, V4, V1, V4
+ FMOVD 8(R4), F1
+ WFMADB V0, V2, V4, V2
+ LDGR R8, F4
+ WFMADB V6, V2, V0, V2
+ WORD $0xED401000 //msdb %f1,%f4,0(%r1)
+ BYTE $0x10
+ BYTE $0x1F
+ MOVD ·logxl2<>+0(SB), R1
+ WORD $0xB3130001 //lcdbr %f0,%f1
+ LDGR R1, F4
+ WFMADB V0, V4, V2, V0
+L1:
+ FMOVD F0, ret+8(FP)
+ RET
+L3:
+ LTDBR F0, F0
+ BEQ L20
+ BGE L1
+ BVS L1
+
+ MOVD $·logxnan<>+0(SB), R1
+ FMOVD 0(R1), F0
+ BR L1
+L20:
+ MOVD $·logxminf<>+0(SB), R1
+ FMOVD 0(R1), F0
+ FMOVD F0, ret+8(FP)
+ RET
+L17:
+ BYTE $0x18 //lr %r5,%r1
+ BYTE $0x51
+ BR L2