/* (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands. See the copyright notice in the ACK home directory, in the file "Copyright". */ /* $Header: /cvsup/minix/src/lib/float/cfi.c,v 1.1.1.1 2005/04/21 14:56:10 beng Exp $ */ /* CONVERT FLOAT TO SIGNED (CFI m n) N.B. The caller must know what it is getting. A LONG is always returned. If it is an integer the high byte is cleared first. */ #include "FP_trap.h" #include "FP_types.h" #include "FP_shift.h" long cfi(ds,ss,src) int ds; /* destination size (2 or 4) */ int ss; /* source size (4 or 8) */ DOUBLE src; /* assume worst case */ { EXTEND buf; long new; short max_exp; extend(&src.d[0],&buf,ss); /* get extended format */ if (buf.exp < 0) { /* no conversion needed */ src.d[ss == 8] = 0L; return(0L); } max_exp = (ds << 3) - 2; /* signed numbers */ /* have more limited max_exp */ if (buf.exp > max_exp) { if (buf.exp == max_exp+1 && buf.sign && buf.m1 == NORMBIT && buf.m2 == 0L) { } else { trap(EIOVFL); /* integer overflow */ buf.exp %= max_exp; /* truncate */ } } new = buf.m1 >> (31-buf.exp); if (buf.sign) new = -new; done: src.d[ss == 8] = new; return(new); }