glibc/sysdeps/powerpc/fpu_control.h

121 lines
3.9 KiB
C

/* FPU control word definitions. PowerPC version.
Copyright (C) 1996-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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, see
<http://www.gnu.org/licenses/>. */
#ifndef _FPU_CONTROL_H
#define _FPU_CONTROL_H
#ifdef _SOFT_FLOAT
# define _FPU_RESERVED 0xffffffff
# define _FPU_DEFAULT 0x00000000 /* Default value. */
typedef unsigned int fpu_control_t;
# define _FPU_GETCW(cw) (cw) = 0
# define _FPU_SETCW(cw) (void) (cw)
extern fpu_control_t __fpu_control;
#elif defined __NO_FPRS__ /* e500 */
/* rounding control */
# define _FPU_RC_NEAREST 0x00 /* RECOMMENDED */
# define _FPU_RC_DOWN 0x03
# define _FPU_RC_UP 0x02
# define _FPU_RC_ZERO 0x01
/* masking of interrupts */
# define _FPU_MASK_ZM 0x10 /* zero divide */
# define _FPU_MASK_OM 0x04 /* overflow */
# define _FPU_MASK_UM 0x08 /* underflow */
# define _FPU_MASK_XM 0x40 /* inexact */
# define _FPU_MASK_IM 0x20 /* invalid operation */
# define _FPU_RESERVED 0x00c10080 /* These bits are reserved and not changed. */
/* Correct IEEE semantics require traps to be enabled at the hardware
level; the kernel then does the emulation and determines whether
generation of signals from those traps was enabled using prctl. */
# define _FPU_DEFAULT 0x0000003c /* Default value. */
# define _FPU_IEEE _FPU_DEFAULT
/* Type of the control word. */
typedef unsigned int fpu_control_t;
/* Macros for accessing the hardware control word. */
# define _FPU_GETCW(cw) \
__asm__ volatile ("mfspefscr %0" : "=r" (cw))
# define _FPU_SETCW(cw) \
__asm__ volatile ("mtspefscr %0" : : "r" (cw))
/* Default control word set at startup. */
extern fpu_control_t __fpu_control;
#else /* PowerPC 6xx floating-point. */
/* rounding control */
# define _FPU_RC_NEAREST 0x00 /* RECOMMENDED */
# define _FPU_RC_DOWN 0x03
# define _FPU_RC_UP 0x02
# define _FPU_RC_ZERO 0x01
# define _FPU_MASK_NI 0x04 /* non-ieee mode */
/* masking of interrupts */
# define _FPU_MASK_ZM 0x10 /* zero divide */
# define _FPU_MASK_OM 0x40 /* overflow */
# define _FPU_MASK_UM 0x20 /* underflow */
# define _FPU_MASK_XM 0x08 /* inexact */
# define _FPU_MASK_IM 0x80 /* invalid operation */
# define _FPU_RESERVED 0xffffff00 /* These bits are reserved are not changed. */
/* The fdlibm code requires no interrupts for exceptions. */
# define _FPU_DEFAULT 0x00000000 /* Default value. */
/* IEEE: same as above, but (some) exceptions;
we leave the 'inexact' exception off.
*/
# define _FPU_IEEE 0x000000f0
/* Type of the control word. */
typedef unsigned int fpu_control_t;
/* Macros for accessing the hardware control word. */
# define _FPU_GETCW(cw) \
({union { double __d; unsigned long long __ll; } __u; \
register double __fr; \
__asm__ ("mffs %0" : "=f" (__fr)); \
__u.__d = __fr; \
(cw) = (fpu_control_t) __u.__ll; \
(fpu_control_t) __u.__ll; \
})
# define _FPU_SETCW(cw) \
{ union { double __d; unsigned long long __ll; } __u; \
register double __fr; \
__u.__ll = 0xfff80000LL << 32; /* This is a QNaN. */ \
__u.__ll |= (cw) & 0xffffffffLL; \
__fr = __u.__d; \
__asm__ ("mtfsf 255,%0" : : "f" (__fr)); \
}
/* Default control word set at startup. */
extern fpu_control_t __fpu_control;
#endif /* PowerPC 6xx floating-point. */
#endif /* _FPU_CONTROL_H */