mirror of
https://github.com/golang/go
synced 2024-11-14 23:20:27 -07:00
7f11db5ea9
sin, cos, tan, asin, acos, atan, exp, log, log10, floor, ceil, and fabs R=rsc CC=golang-dev https://golang.org/cl/189083
41 lines
1.3 KiB
ArmAsm
41 lines
1.3 KiB
ArmAsm
// 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.
|
|
|
|
// func Exp(x float64) float64
|
|
TEXT math·Exp(SB),7,$0
|
|
// test bits for not-finite
|
|
MOVL x+4(FP), AX
|
|
ANDL $0x7ff00000, AX
|
|
CMPL AX, $0x7ff00000
|
|
JEQ not_finite
|
|
FLDL2E // F0=log2(e)
|
|
FMOVD x+0(FP), F0 // F0=x, F1=log2(e)
|
|
FMULDP F0, F1 // F0=x*log2(e)
|
|
FMOVD F0, F1 // F0=x*log2(e), F1=x*log2(e)
|
|
FRNDINT // F0=int(x*log2(e)), F1=x*log2(e)
|
|
FSUBD F0, F1 // F0=int(x*log2(e)), F1=x*log2(e)-int(x*log2(e))
|
|
FXCHD F0, F1 // F0=x*log2(e)-int(x*log2(e)), F1=int(x*log2(e))
|
|
F2XM1 // F0=2**(x*log2(e)-int(x*log2(e)))-1, F1=int(x*log2(e))
|
|
FLD1 // F0=1, F1=2**(x*log2(e)-int(x*log2(e)))-1, F2=int(x*log2(e))
|
|
FADDDP F0, F1 // F0=2**(x*log2(e)-int(x*log2(e))), F1=int(x*log2(e))
|
|
FSCALE // F0=e**x, F1=int(x*log2(e))
|
|
FMOVDP F0, F1 // F0=e**x
|
|
FMOVDP F0, r+8(FP)
|
|
RET
|
|
not_finite:
|
|
// test bits for -Inf
|
|
MOVL x+4(FP), BX
|
|
MOVL x+0(FP), CX
|
|
CMPL BX, $0xfff00000
|
|
JNE not_neginf
|
|
CMPL CX, $0
|
|
JNE not_neginf
|
|
MOVL $0, r+8(FP)
|
|
MOVL $0, r+12(FP)
|
|
RET
|
|
not_neginf:
|
|
MOVL CX, r+8(FP)
|
|
MOVL BX, r+12(FP)
|
|
RET
|