mirror of
git://sourceware.org/git/glibc.git
synced 2024-12-27 04:41:02 +08:00
162 lines
5.0 KiB
ArmAsm
162 lines
5.0 KiB
ArmAsm
/* Copyright (C) 1996 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by David Mosberger <davidm@cs.arizona.edu>, 1996.
|
|
Based on public-domain C source by Linus Torvalds.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Library General Public License as
|
|
published by the Free Software Foundation; either version 2 of the
|
|
License, or (at your option) any later version.
|
|
|
|
The GNU C Library is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
Library General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Library General Public
|
|
License along with the GNU C Library; see the file COPYING.LIB. If not,
|
|
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, USA. */
|
|
|
|
/* This version is much faster than generic sqrt implementation, but
|
|
it doesn't handle exceptional values or the inexact flag. Don't use
|
|
this if _IEEE_FP or _IEEE_FP_INEXACT is in effect. */
|
|
|
|
#ifndef _IEEE_FP
|
|
|
|
#define _ERRNO_H
|
|
#include <errnos.h>
|
|
#include <sysdep.h>
|
|
|
|
.set noreorder
|
|
|
|
#ifdef __ELF__
|
|
.section .rodata
|
|
#else
|
|
.rdata
|
|
#endif
|
|
.align 5 # align to cache line
|
|
|
|
/* Do all memory accesses relative to sqrtdata. */
|
|
sqrtdata:
|
|
|
|
#define DN 0x00
|
|
#define UP 0x08
|
|
#define HALF 0x10
|
|
#define ALMOST_THREE_HALF 0x18
|
|
#define T2 0x20
|
|
|
|
.quad 0x3fefffffffffffff /* DN = next(1.0) */
|
|
.quad 0x3ff0000000000001 /* UP = prev(1.0) */
|
|
.quad 0x3fe0000000000000 /* HALF = 0.5 */
|
|
.quad 0x3ff7ffffffc00000 /* ALMOST_THREE_HALF = 1.5-2^-30 */
|
|
|
|
/* table T2: */
|
|
.long 0x1500, 0x2ef8, 0x4d67, 0x6b02, 0x87be, 0xa395, 0xbe7a, 0xd866
|
|
.long 0xf14a, 0x1091b, 0x11fcd, 0x13552, 0x14999, 0x15c98, 0x16e34, 0x17e5f
|
|
.long 0x18d03, 0x19a01, 0x1a545, 0x1ae8a, 0x1b5c4, 0x1bb01, 0x1bfde, 0x1c28d
|
|
.long 0x1c2de, 0x1c0db, 0x1ba73, 0x1b11c, 0x1a4b5, 0x1953d, 0x18266, 0x16be0
|
|
.long 0x1683e, 0x179d8, 0x18a4d, 0x19992, 0x1a789, 0x1b445, 0x1bf61, 0x1c989
|
|
.long 0x1d16d, 0x1d77b, 0x1dddf, 0x1e2ad, 0x1e5bf, 0x1e6e8, 0x1e654, 0x1e3cd
|
|
.long 0x1df2a, 0x1d635, 0x1cb16, 0x1be2c, 0x1ae4e, 0x19bde, 0x1868e, 0x16e2e
|
|
.long 0x1527f, 0x1334a, 0x11051, 0xe951, 0xbe01, 0x8e0d, 0x5924, 0x1edd
|
|
|
|
/*
|
|
* Stack variables:
|
|
*/
|
|
#define K 16(sp)
|
|
#define Y 24(sp)
|
|
#define FSIZE 32
|
|
|
|
.text
|
|
|
|
LEAF(__sqrt, FSIZE)
|
|
lda sp, -FSIZE(sp)
|
|
ldgp gp, .-__sqrt(pv)
|
|
stq ra, 0(sp)
|
|
#ifdef PROF
|
|
lda AT, _mcount
|
|
jsr AT, (AT), _mcount
|
|
#endif
|
|
.prologue 1
|
|
|
|
stt $f16, K
|
|
lda t3, sqrtdata # load base address into t3
|
|
|
|
fblt $f16, $negative
|
|
|
|
/* Compute initial guess. */
|
|
|
|
.align 3
|
|
|
|
ldah t1, 0x5fe8 # e0 :
|
|
ldq t2, K # .. e1 :
|
|
ldt $f12, HALF(t3) # e0 :
|
|
ldt $f18, ALMOST_THREE_HALF(t3) # .. e1 :
|
|
srl t2, 33, t0 # e0 :
|
|
mult $f16, $f12, $f11 # .. fm : $f11 = x * 0.5
|
|
subl t1, t0, t1 # e0 :
|
|
addt $f12, $f12, $f17 # .. fa : $f17 = 1.0
|
|
srl t1, 12, t0 # e0 :
|
|
and t0, 0xfc, t0 # .. e1 :
|
|
addq t0, t3, t0 # e0 :
|
|
ldl t0, T2(t0) # .. e1 :
|
|
addt $f12, $f17, $f15 # fa : $f15 = 1.5
|
|
subl t1, t0, t1 # .. e1 :
|
|
sll t1, 32, t1 # e0 :
|
|
ldt $f14, DN(t3) # .. e1 :
|
|
stq t1, Y # e0 :
|
|
ldt $f13, Y # e1 :
|
|
addq sp, FSIZE, sp # e0 :
|
|
|
|
mult $f11, $f13, $f10 # fm : $f10 = (x * 0.5) * y
|
|
mult $f10, $f13, $f10 # fm : $f10 = ((x * 0.5) * y) * y
|
|
subt $f15, $f10, $f1 # fa : $f1 = (1.5 - 0.5*x*y*y)
|
|
mult $f13, $f1, $f13 # fm : yp = y*(1.5 - 0.5*x*y*y)
|
|
mult $f11, $f13, $f11 # fm : $f11 = x * 0.5 * yp
|
|
mult $f11, $f13, $f11 # fm : $f11 = (x * 0.5 * yp) * yp
|
|
subt $f18, $f11, $f1 # fa : $f1= (1.5-2^-30) - 0.5*x*yp*yp
|
|
mult $f13, $f1, $f13 # fm : ypp = $f13 = yp*$f1
|
|
subt $f15, $f12, $f1 # fa : $f1 = (1.5 - 0.5)
|
|
ldt $f15, UP(t3) # .. e1 :
|
|
mult $f16, $f13, $f10 # fm : z = $f10 = x * ypp
|
|
mult $f10, $f13, $f11 # fm : $f11 = z*ypp
|
|
mult $f10, $f12, $f12 # fm : $f12 = z*0.5
|
|
subt $f1, $f11, $f1 # .. fa : $f1 = 1 - z*ypp
|
|
mult $f12, $f1, $f12 # fm : $f12 = z*0.5*(1 - z*ypp)
|
|
addt $f10, $f12, $f0 # fa : zp=res=$f0= z + z*0.5*(1 - z*ypp)
|
|
|
|
mult/c $f0, $f14, $f12 # fm : zmi = zp * DN
|
|
mult/c $f0, $f15, $f11 # fm : zpl = zp * UP
|
|
mult/c $f0, $f12, $f1 # fm : $f1 = zp * zmi
|
|
mult/c $f0, $f11, $f15 # fm : $f15 = zp * zpl
|
|
|
|
subt $f1, $f16, $f13 # fa : y1 = zp*zmi - x
|
|
subt $f15, $f16, $f15 # fa : y2 = zp*zpl - x
|
|
|
|
fcmovge $f13, $f12, $f0 # res = (y1 >= 0) ? zmi : res
|
|
fcmovlt $f15, $f11, $f0 # res = (y2 < 0) ? zpl : res
|
|
|
|
ret
|
|
|
|
$negative:
|
|
lda t1, -1
|
|
stq t1, K
|
|
lda t1, EDOM
|
|
stl t1, errno
|
|
#ifdef _LIBC_REENTRANT
|
|
jsr ra, __errno_location
|
|
lda t1, -1
|
|
ldq ra, 0(sp)
|
|
stl t1, 0(v0)
|
|
#endif
|
|
ldt $f0, K # res = (double) 0xffffffffffffffff
|
|
addq sp, FSIZE, sp
|
|
ret
|
|
|
|
END(__sqrt)
|
|
|
|
weak_alias(__sqrt, sqrt)
|
|
|
|
#endif /* !_IEEE_FP */
|