ref: 6dce09cec3bf6a689fa9a3f838df67d7d48d9d1a
dir: /libmath/FPcontrol-Nt.c/
#include "lib9.h" #include <float.h> #include "mathi.h" void FPinit(void) { _controlfp(_EM_INEXACT,_MCW_EM); // abort on underflow, etc. } ulong getFPstatus(void) { ulong fsr = 0, fsr32 = _statusfp(); if(fsr32&_SW_INEXACT) fsr |= INEX; if(fsr32&_SW_OVERFLOW) fsr |= OVFL; if(fsr32&_SW_UNDERFLOW) fsr |= UNFL; if(fsr32&_SW_ZERODIVIDE) fsr |= ZDIV; if(fsr32&_SW_INVALID) fsr |= INVAL; return fsr; } ulong FPstatus(ulong fsr, ulong mask) { ulong old = getFPstatus(); fsr = (fsr&mask) | (old&~mask); if(fsr!=old){ _clearfp(); if(fsr){ ulong fcr = _controlfp(0,0); double x = 1., y = 1e200, z = 0.; _controlfp(_MCW_EM,_MCW_EM); if(fsr&INEX) z = x + y; if(fsr&OVFL) z = y*y; if(fsr&UNFL) z = (x/y)/y; if(fsr&ZDIV) z = x/z; if(fsr&INVAL) z = z/z; _controlfp(fcr,_MCW_EM); } } return(old&mask); } ulong getFPcontrol(void) { ulong fcr, fcr32 = _controlfp(0,0); switch(fcr32&_MCW_RC){ case _RC_NEAR: fcr = RND_NR; break; case _RC_DOWN: fcr = RND_NINF; break; case _RC_UP: fcr = RND_PINF; break; case _RC_CHOP: fcr = RND_Z; break; } if(!(fcr32&_EM_INEXACT)) fcr |= INEX; if(!(fcr32&_EM_OVERFLOW)) fcr |= OVFL; if(!(fcr32&_EM_UNDERFLOW)) fcr |= UNFL; if(!(fcr32&_EM_ZERODIVIDE)) fcr |= ZDIV; if(!(fcr32&_EM_INVALID)) fcr |= INVAL; return fcr; } ulong FPcontrol(ulong fcr, ulong mask) { ulong old = getFPcontrol(); ulong fcr32 = _MCW_EM, mask32 = _MCW_RC|_MCW_EM; fcr = (fcr&mask) | (old&~mask); if(fcr&INEX) fcr32 ^= _EM_INEXACT; if(fcr&OVFL) fcr32 ^= _EM_OVERFLOW; if(fcr&UNFL) fcr32 ^= _EM_UNDERFLOW; if(fcr&ZDIV) fcr32 ^= _EM_ZERODIVIDE; if(fcr&INVAL) fcr32 ^= _EM_INVALID; switch(fcr&RND_MASK){ case RND_NR: fcr32 |= _RC_NEAR; break; case RND_NINF: fcr32 |= _RC_DOWN; break; case RND_PINF: fcr32 |= _RC_UP; break; case RND_Z: fcr32 |= _RC_CHOP; break; } _controlfp(fcr32,mask32); return(old&mask); }