ref: 76b565d8b219c8db94a882e93725b4ab735414de
dir: /libmath/FPcontrol-Irix.c/
/* Load programs with -lfpe. See man pages for fpc and /usr/include/sigfpe.h, sys/fpu.h. */ #include <stdlib.h> #include <sigfpe.h> #include <sys/fpu.h> typedef unsigned int ulong; #include "mathi.h" /* * Irix does not permit a use handled SIGFPE since the floating point unit * cannot be IEEE754 compliant without some software, so we must vector using * the library */ extern void trapFPE(unsigned exception[5], int value[2]); void FPinit(void) { union fpc_csr csr; int i; for(i=1; i<=4; i++) { sigfpe_[i].repls = _USER_DETERMINED; sigfpe_[i].abort = 2; } handle_sigfpes(_ON, _EN_UNDERFL|_EN_OVERFL|_EN_DIVZERO|_EN_INVALID, trapFPE, _ABORT_ON_ERROR, 0); } ulong getFPstatus(void) { ulong fsr = 0; union fpc_csr csr; csr.fc_word = get_fpc_csr(); if(csr.fc_struct.se_inexact) fsr |= INEX; if(csr.fc_struct.se_overflow) fsr |= OVFL; if(csr.fc_struct.se_underflow) fsr |= UNFL; if(csr.fc_struct.se_divide0) fsr |= ZDIV; if(csr.fc_struct.se_invalid) fsr |= INVAL; return fsr; } ulong FPstatus(ulong fsr, ulong mask) { ulong old = getFPstatus(); union fpc_csr csr; csr.fc_word = get_fpc_csr(); fsr = (fsr&mask) | (old&~mask); csr.fc_struct.se_inexact = (fsr&INEX)?1:0; csr.fc_struct.se_overflow = (fsr&OVFL)?1:0; csr.fc_struct.se_underflow = (fsr&UNFL)?1:0; csr.fc_struct.se_divide0 = (fsr&ZDIV)?1:0; csr.fc_struct.se_invalid = (fsr&INVAL)?1:0; set_fpc_csr(csr.fc_word); return(old&mask); } ulong getFPcontrol(void) { ulong fcr = 0; union fpc_csr csr; double junk = fabs(1.); /* avoid bug mentioned in sigfpes man page [ehg] */ csr.fc_word = get_fpc_csr(); switch(csr.fc_struct.rounding_mode){ case ROUND_TO_NEAREST: fcr = RND_NR; break; case ROUND_TO_MINUS_INFINITY: fcr = RND_NINF; break; case ROUND_TO_PLUS_INFINITY: fcr = RND_PINF; break; case ROUND_TO_ZERO: fcr = RND_Z; break; } if(csr.fc_struct.en_inexact) fcr |= INEX; if(csr.fc_struct.en_overflow) fcr |= OVFL; if(csr.fc_struct.en_underflow) fcr |= UNFL; if(csr.fc_struct.en_divide0) fcr |= ZDIV; if(csr.fc_struct.en_invalid) fcr |= INVAL; return fcr; } ulong FPcontrol(ulong fcr, ulong mask) { ulong old = getFPcontrol(); union fpc_csr csr; csr.fc_word = get_fpc_csr(); fcr = (fcr&mask) | (old&~mask); csr.fc_struct.en_inexact = (fcr&INEX)?1:0; csr.fc_struct.en_overflow = (fcr&OVFL)?1:0; csr.fc_struct.en_underflow = (fcr&UNFL)?1:0; csr.fc_struct.en_divide0 = (fcr&ZDIV)?1:0; csr.fc_struct.en_invalid = (fcr&INVAL)?1:0; switch(fcr&RND_MASK){ case RND_NR: csr.fc_struct.rounding_mode = ROUND_TO_NEAREST; break; case RND_NINF: csr.fc_struct.rounding_mode = ROUND_TO_MINUS_INFINITY; break; case RND_PINF: csr.fc_struct.rounding_mode = ROUND_TO_PLUS_INFINITY; break; case RND_Z: csr.fc_struct.rounding_mode = ROUND_TO_ZERO; break; } set_fpc_csr(csr.fc_word); return(old&mask); }