diff options
Diffstat (limited to 'rnd_mode.c')
| -rw-r--r-- | rnd_mode.c | 77 |
1 files changed, 77 insertions, 0 deletions
diff --git a/rnd_mode.c b/rnd_mode.c new file mode 100644 index 000000000..ad48ce95c --- /dev/null +++ b/rnd_mode.c @@ -0,0 +1,77 @@ +/* functions to set/get the machine rounding mode, + this should use the interface from the ISO C9X draft + (file <fenv.h>) */ + +#include <stdio.h> +#include "gmp.h" +#include "mpfr.h" + +#ifdef IRIX64 +#include <sys/fpu.h> +#define TOZERO swapRM(ROUND_TO_ZERO) +#define TOINFP swapRM(ROUND_TO_PLUS_INFINITY) +#define TONEAREST swapRM(ROUND_TO_NEAREST) +#define TOINFM swapRM(ROUND_TO_MINUS_INFINITY) +#elif (defined (solaris) || defined (sun4)) +#include <ieeefp.h> +#define TOZERO fpsetround(FP_RZ) +#define TOINFP fpsetround(FP_RP) +#define TONEAREST fpsetround(FP_RN) +#define TOINFM fpsetround(FP_RM) +#elif alpha +#ifdef __GNUC__ +/* GCC patched include files forget to define those... */ +#define FP_RND_RZ 0 +#define FP_RND_RN 1 +#define FP_RND_RP 2 +#define FP_RND_RM 3 +#endif +#include <float.h> +#define TOZERO write_rnd(FP_RND_RZ) +#define TOINFP write_rnd(FP_RND_RP) +#define TONEAREST write_rnd(FP_RND_RN) +#define TOINFM write_rnd(FP_RND_RM) +#elif AIX +#include <float.h> +#define TOZERO fp_swap_rnd(FP_RND_RZ) +#define TOINFP fp_swap_rnd(FP_RND_RP) +#define TONEAREST fp_swap_rnd(FP_RND_RN) +#define TOINFM fp_swap_rnd(FP_RND_RM) +#elif sunos +#include <floatingpoint.h> +char *out; +#define TOZERO ieee_flags("set","direction","tozero",&out) +#define TOINFP ieee_flags("set","direction","positive",&out) +#define TONEAREST ieee_flags("set","direction","nearest",&out) +#define TOINFM ieee_flags("set","direction","negative",&out) +#elif hp700 +#define TOZERO fpsetround(FP_RZ) +#define TOINFP fpsetround(FP_RP) +#define TONEAREST fpsetround(FP_RN) +#define TOINFM fpsetround(FP_RM) +#elif (defined (__i386__) || defined (__i486__) || defined (linux)) +#include <fpu_control.h> +#ifdef LIBC211 +#define __setfpucw(cw) __asm__ ("fldcw %0" : : "m" (cw)) +#endif +/* be careful to put bits 9-8 (Precision control) + to 10 (round to double precision) instead of the + default 11 (round to extended precision) */ +#define TOZERO __setfpucw(0x1e7f) +#define TOINFP __setfpucw(0x1a7f) +#define TOINFM __setfpucw(0x167f) +#define TONEAREST __setfpucw(0x127f) +#endif + +/* sets the machine rounding mode to the value rnd_mode */ +void mpfr_set_machine_rnd_mode(unsigned char rnd_mode) +{ + switch (rnd_mode) { + case GMP_RNDN: TONEAREST; break; + case GMP_RNDZ: TOZERO; break; + case GMP_RNDU: TOINFP; break; + case GMP_RNDD: TOINFM; break; + default: fprintf(stderr,"invalid rounding mode\n"); exit(1); + } +} + |