glibc/sysdeps/i386/fpu_control.h
Ulrich Drepper cb0509a8d5 Update.
1998-11-26  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/mips/dl-machine.h (ELF_MACHINE_NO_PLT): New defined macro.
	(elf_machine_got_rel): Remove scope variable.  Use scope from the map.
	Don't modify _dl_global_scope_end in the end.
	(__dl_runtime_resolv): Also use scope from the map.
	* sysdeps/mips/mips64/dl-machine.h: Likewise.
	* elf/dl-runtime.c: Don't define fixup and profile_fixup if
	ELF_MACHINE_NO_PLT is defined.
	* sysdeps/mips/sys/ucontext.h: New file.
	Patches by kaz Kojima <kkojima@rr.iij4u.or.jp>.

1998-11-26  Andreas Jaeger  <aj@arthur.rhein-neckar.de> 
 
	* sysdeps/generic/pselect.c (__pselect): Change interface, 
	set/restore sigmask. 
 
	* misc/sys/select.h: Change declaration according to Stevens' Unix  
	Network Programming. 
	* include/sys/select.h (__pselect): Likewise. 
	Reported by <bwelling@anomaly.munge.com> [PR libc/872]. 
 
	* include/fpu_control.h: New file, contains __setfpucw 
	declaration. 
 
	* sysdeps/generic/fpu_control.h: Remove __setfpucw declaration, 
	it's an internal symbol. 
	* sysdeps/alpha/fpu/fpu_control.h: Likewise. 
	* sysdeps/arm/fpu/fpu_control.h: Likewise. 
	* sysdeps/i386/fpu_control.h: Likewise. 
	* sysdeps/m68k/fpu_control.h: Likewise. 
	* sysdeps/powerpc/fpu_control.h: Likewise. 
	* sysdeps/sparc/sparc32/fpu/fpu_control.h: Likewise. 
	* sysdeps/sparc/sparc64/fpu/fpu_control.h: Likewise.
1998-11-26 12:02:23 +00:00

99 lines
3 KiB
C

/* FPU control word bits. i387 version.
Copyright (C) 1993, 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Olaf Flebbe.
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. */
#ifndef _FPU_CONTROL_H
#define _FPU_CONTROL_H 1
/* Here is the dirty part. Set up your 387 through the control word
* (cw) register.
*
* 15-13 12 11-10 9-8 7-6 5 4 3 2 1 0
* | reserved | IC | RC | PC | reserved | PM | UM | OM | ZM | DM | IM
*
* IM: Invalid operation mask
* DM: Denormalized operand mask
* ZM: Zero-divide mask
* OM: Overflow mask
* UM: Underflow mask
* PM: Precision (inexact result) mask
*
* Mask bit is 1 means no interrupt.
*
* PC: Precision control
* 11 - round to extended precision
* 10 - round to double precision
* 00 - round to single precision
*
* RC: Rounding control
* 00 - rounding to nearest
* 01 - rounding down (toward - infinity)
* 10 - rounding up (toward + infinity)
* 11 - rounding toward zero
*
* IC: Infinity control
* That is for 8087 and 80287 only.
*
* The hardware default is 0x037f. I choose 0x1372.
*/
#include <features.h>
/* masking of interrupts */
#define _FPU_MASK_IM 0x01
#define _FPU_MASK_DM 0x02
#define _FPU_MASK_ZM 0x04
#define _FPU_MASK_OM 0x08
#define _FPU_MASK_UM 0x10
#define _FPU_MASK_PM 0x20
/* precision control */
#define _FPU_EXTENDED 0x300
#define _FPU_DOUBLE 0x200 /* fdlibm requires double precision */
#define _FPU_SINGLE 0x0 /* DO NOT USE */
/* rounding control */
#define _FPU_RC_NEAREST 0x0 /* RECOMMENDED */
#define _FPU_RC_DOWN 0x400
#define _FPU_RC_UP 0x800
#define _FPU_RC_ZERO 0xC00
#define _FPU_RESERVED 0xF0C0 /* Reserved bits in cw */
/* The fdlibm code requires strict IEEE double precision arithmetic,
and no interrupts for exceptions, rounding to nearest. */
#define _FPU_DEFAULT 0x137f
/* IEEE: same as above. */
#define _FPU_IEEE 0x137f
/* Type of the control word. */
typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__HI__)));
/* Macros for accessing the hardware control word. */
#define _FPU_GETCW(cw) __asm__ ("fnstcw %0" : "=m" (*&cw))
#define _FPU_SETCW(cw) __asm__ ("fldcw %0" : : "m" (*&cw))
/* Default control word set at startup. */
extern fpu_control_t __fpu_control;
#endif /* fpu_control.h */