blob: 8640bbc223a1d47a5442f792ad777bf6649b8de7 [file] [log] [blame]
/* ix87 specific frexp implementation for float.
Copyright (C) 1997, 2000, 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <machine/asm.h>
#include "bp-sym.h"
#include "bp-asm.h"
#ifdef __ELF__
.section .rodata
#else
.text
#endif
.align ALIGNARG(4)
ASM_TYPE_DIRECTIVE(two25,@object)
two25: .byte 0, 0, 0, 0x4c
ASM_SIZE_DIRECTIVE(two25)
#ifdef PIC
#define MO(op) op##@GOTOFF(%edx)
#else
#define MO(op) op
#endif
#define PARMS LINKAGE /* no space for saved regs */
#define VAL PARMS
#define EXPP VAL+4
.text
ENTRY (BP_SYM (__frexpf))
ENTER
movl VAL(%esp), %eax
xorl %ecx, %ecx
movl %eax, %edx
andl $0x7fffffff, %eax
jz 1f
cmpl $0x7f800000, %eax
jae 1f
cmpl $0x00800000, %eax
jae 2f
flds VAL(%esp)
#ifdef PIC
LOAD_PIC_REG (dx)
#endif
fmuls MO(two25)
movl $-25, %ecx
fstps VAL(%esp)
fwait
movl VAL(%esp), %eax
movl %eax, %edx
andl $0x7fffffff, %eax
2: shrl $23, %eax
andl $0x807fffff, %edx
subl $126, %eax
orl $0x3f000000, %edx
addl %eax, %ecx
movl %edx, VAL(%esp)
/* Store %ecx in the variable pointed to by the second argument,
get the factor from the stack and return. */
1: movl EXPP(%esp), %eax
CHECK_BOUNDS_BOTH_WIDE (%eax, EXPP(%esp), $4)
flds VAL(%esp)
movl %ecx, (%eax)
LEAVE
ret
END (BP_SYM (__frexpf))
weak_alias (BP_SYM (__frexpf), BP_SYM (frexpf))