1 files changed, 174 insertions, 0 deletions
diff --git a/src/math/atanh_s390x.s b/src/math/atanh_s390x.s
new file mode 100644
index 0000000..c4ec2b2
--- /dev/null
+++ b/src/math/atanh_s390x.s
@@ -0,0 +1,174 @@
+// 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