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Diffstat (limited to 'src/pkg/math/exp_amd64.s')
| -rw-r--r-- | src/pkg/math/exp_amd64.s | 114 |
1 files changed, 0 insertions, 114 deletions
diff --git a/src/pkg/math/exp_amd64.s b/src/pkg/math/exp_amd64.s deleted file mode 100644 index d9cf8fd86..000000000 --- a/src/pkg/math/exp_amd64.s +++ /dev/null @@ -1,114 +0,0 @@ -// Copyright 2010 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" - -// The method is based on a paper by Naoki Shibata: "Efficient evaluation -// methods of elementary functions suitable for SIMD computation", Proc. -// of International Supercomputing Conference 2010 (ISC'10), pp. 25 -- 32 -// (May 2010). The paper is available at -// http://www.springerlink.com/content/340228x165742104/ -// -// The original code and the constants below are from the author's -// implementation available at http://freshmeat.net/projects/sleef. -// The README file says, "The software is in public domain. -// You can use the software without any obligation." -// -// This code is a simplified version of the original. - -#define LN2 0.6931471805599453094172321214581766 // log_e(2) -#define LOG2E 1.4426950408889634073599246810018920 // 1/LN2 -#define LN2U 0.69314718055966295651160180568695068359375 // upper half LN2 -#define LN2L 0.28235290563031577122588448175013436025525412068e-12 // lower half LN2 -#define T0 1.0 -#define T1 0.5 -#define T2 1.6666666666666666667e-1 -#define T3 4.1666666666666666667e-2 -#define T4 8.3333333333333333333e-3 -#define T5 1.3888888888888888889e-3 -#define T6 1.9841269841269841270e-4 -#define T7 2.4801587301587301587e-5 -#define PosInf 0x7FF0000000000000 -#define NegInf 0xFFF0000000000000 - -// func Exp(x float64) float64 -TEXT ·Exp(SB),NOSPLIT,$0 -// test bits for not-finite - MOVQ x+0(FP), BX - MOVQ $~(1<<63), AX // sign bit mask - MOVQ BX, DX - ANDQ AX, DX - MOVQ $PosInf, AX - CMPQ AX, DX - JLE notFinite - MOVQ BX, X0 - MOVSD $LOG2E, X1 - MULSD X0, X1 - CVTSD2SL X1, BX // BX = exponent - CVTSL2SD BX, X1 - MOVSD $LN2U, X2 - MULSD X1, X2 - SUBSD X2, X0 - MOVSD $LN2L, X2 - MULSD X1, X2 - SUBSD X2, X0 - // reduce argument - MULSD $0.0625, X0 - // Taylor series evaluation - MOVSD $T7, X1 - MULSD X0, X1 - ADDSD $T6, X1 - MULSD X0, X1 - ADDSD $T5, X1 - MULSD X0, X1 - ADDSD $T4, X1 - MULSD X0, X1 - ADDSD $T3, X1 - MULSD X0, X1 - ADDSD $T2, X1 - MULSD X0, X1 - ADDSD $T1, X1 - MULSD X0, X1 - ADDSD $T0, X1 - MULSD X1, X0 - MOVSD $2.0, X1 - ADDSD X0, X1 - MULSD X1, X0 - MOVSD $2.0, X1 - ADDSD X0, X1 - MULSD X1, X0 - MOVSD $2.0, X1 - ADDSD X0, X1 - MULSD X1, X0 - MOVSD $2.0, X1 - ADDSD X0, X1 - MULSD X1, X0 - ADDSD $1.0, X0 - // return fr * 2**exponent - MOVL $0x3FF, AX // bias - ADDL AX, BX - JLE underflow - CMPL BX, $0x7FF - JGE overflow - MOVL $52, CX - SHLQ CX, BX - MOVQ BX, X1 - MULSD X1, X0 - MOVSD X0, ret+8(FP) - RET -notFinite: - // test bits for -Inf - MOVQ $NegInf, AX - CMPQ AX, BX - JNE notNegInf - // -Inf, return 0 -underflow: // return 0 - MOVQ $0, AX - MOVQ AX, ret+8(FP) - RET -overflow: // return +Inf - MOVQ $PosInf, BX -notNegInf: // NaN or +Inf, return x - MOVQ BX, ret+8(FP) - RET |