/* FPU control word definitions. PowerPC and PowerPC e500 versions. Copyright (C) 1996, 1997, 1998, 2004 Free Software Foundation, Inc. This file is part of the GNU C Library. e500 parts contributed by Aldy Hernandez <aldy@redhat.com>. 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 #include <features.h> /* 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 */ /* The fdlibm code requires no interrupts for exceptions. */ #define _FPU_DEFAULT 0x00000000 /* Default value. */ /* Type of the control word. */ typedef unsigned int fpu_control_t __attribute__ ((__mode__ (__SI__))); #ifdef __CONFIG_E500__ #define _FPU_RESERVED 0xff3fff7f /* These bits are reserved are not changed. */ /* IEEE: same as above, but (some) exceptions; we leave the 'inexact' exception off. */ #define _FPU_IEEE 0x000003c0 /* Macros for accessing the hardware control word. */ #define _FPU_GETCW(__cw) ({ \ unsigned int env; \ __asm__ __volatile__ ("mfspefscr %0" : "=r" (env)); \ (__cw) = env; }) #define _FPU_SETCW(__cw) ({ \ unsigned int env = __cw; \ __asm__ __volatile__ ("mtspefscr %0" : : "r" (env)); }) #else #define _FPU_RESERVED 0xffffff00 /* These bits are reserved are not changed. */ /* IEEE: same as above, but (some) exceptions; we leave the 'inexact' exception off. */ #define _FPU_IEEE 0x000000f0 /* Macros for accessing the hardware control word. */ #define _FPU_GETCW(__cw) ( { \ union { double d; fpu_control_t cw[2]; } \ tmp __attribute__ ((__aligned__(8))); \ __asm__ ("mffs 0; stfd%U0 0,%0" : "=m" (tmp.d) : : "fr0"); \ (__cw)=tmp.cw[1]; \ tmp.cw[1]; } ) #define _FPU_SETCW(__cw) { \ union { double d; fpu_control_t cw[2]; } \ tmp __attribute__ ((__aligned__(8))); \ tmp.cw[0] = 0xFFF80000; /* More-or-less arbitrary; this is a QNaN. */ \ tmp.cw[1] = __cw; \ __asm__ ("lfd%U0 0,%0; mtfsf 255,0" : : "m" (tmp.d) : "fr0"); \ } #endif /* __CONFIG_E500__ */ #if 0 /* Default control word set at startup. */ extern fpu_control_t __fpu_control; #endif #endif /* _FPU_CONTROL_H */