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Diffstat (limited to 'sysdeps/mips/fpu_control.h')
| -rw-r--r-- | sysdeps/mips/fpu_control.h | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/sysdeps/mips/fpu_control.h b/sysdeps/mips/fpu_control.h new file mode 100644 index 0000000000..36e05a4f6e --- /dev/null +++ b/sysdeps/mips/fpu_control.h @@ -0,0 +1,96 @@ +/* FPU control word bits. Mips version. + Copyright (C) 1996, 1997 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 + +/* FP control/status register bit assignments. + * + * 31-25 24 23 22-18 17-12 11-7 6-2 1-0 + * (cause) (enables) (flags) + * | reserved | FS | C | reserved | E V Z O U I | V Z O U I | V Z O U I | RM + * + * FS: When set, denormalized results are flushed to zero instead of + * causing an unimplemented operation exception. + * C: Condition bit. + * E: Unimplemented Operation. + * V: Invalid Operation. + * Z: Division by zero. + * O: Overflow. + * U: Underflow. + * I: Inexact Operation + * RM: Rounding mode bits + * 00 (RN) - rounding to nearest + * 01 (RZ) - rounding toward zero + * 10 (RP) - rounding down (toward - infinity) + * 11 (RM) - rounding up (toward + infinity) + * + */ + +#include <features.h> + +/* masking of interrupts */ +#define _FPU_MASK_IM (1 << 11) +#define _FPU_MASK_DM (1 << 24) /* XXX */ +#define _FPU_MASK_ZM (1 << 10) +#define _FPU_MASK_OM (1 << 9) +#define _FPU_MASK_UM (1 << 8) +#define _FPU_MASK_PM (1 << 7) + +/* precision control */ +#define _FPU_EXTENDED 0 +#define _FPU_DOUBLE 0 +#define _FPU_SINGLE 0 + +/* rounding control */ +#define _FPU_RC_NEAREST 0x0 /* RECOMMENDED */ +#define _FPU_RC_DOWN 0x2 +#define _FPU_RC_UP 0x3 +#define _FPU_RC_ZERO 0x1 + +#define _FPU_RESERVED 0xfe7c0000 /* Reserved bits */ + + +/* The fdlibm code requires strict IEEE double precision arithmetic, + and no interrupts for exceptions, rounding to nearest. */ + +#define _FPU_DEFAULT 0x0 + +/* IEEE: same as above, but exceptions */ +#define _FPU_IEEE (0x1f << 7) + +/* Type of the control word. */ +typedef unsigned int fpu_control_t; + +/* Macros for accessing the hardware control word. */ +#define _FPU_GETCW(cw) __asm__ ("cfc1 %0, $31; nop; nop" : "=r" (cw)) +#define _FPU_SETCW(cw) __asm__ ("ctc1 %0, $31; nop; nop" : : "r" (cw)) + +/* Default control word set at startup. */ +extern fpu_control_t __fpu_control; + +__BEGIN_DECLS + +/* Called at startup. It can be used to manipulate fpu control register. */ +extern void __setfpucw __P ((fpu_control_t)); + +__END_DECLS + +#endif /* fpu_control.h */ |