53 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			53 lines
		
	
	
	
		
			1.2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|   (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
 | |
|   See the copyright notice in the ACK home directory, in the file "Copyright".
 | |
| */
 | |
| 
 | |
| /* $Header$ */
 | |
| 
 | |
| /*
 | |
| 		CONVERT FLOAT TO UNSIGNED
 | |
| 
 | |
| 		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"
 | |
| 
 | |
| 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	newint,	max_exp;
 | |
| 
 | |
| 	extend(&src,&buf,ss);	/* get extended format */
 | |
| #ifdef	PRT_EXT
 | |
| 	prt_ext("CFI() entry:",&buf);
 | |
| #endif	PRT_EXT
 | |
| 	buf.exp--;		/* additional bias correction */
 | |
| 	if (buf.exp < 1) {	/* no conversion needed */
 | |
| 		src.__double[ss == 8] = 0L;
 | |
| 		return(0L);
 | |
| 	}
 | |
| 	max_exp = (ds << 3) - 1;	/* signed numbers */
 | |
| 				/* have more limited max_exp */
 | |
| 	if (buf.exp > max_exp) {
 | |
| #ifdef	PRT_EXT
 | |
| 		prt_ext("CFI() INT OVERFLOW", &buf);
 | |
| #endif	PRT_EXT
 | |
| 		trap(EIOVFL);	/* integer overflow	*/
 | |
| 		buf.exp %= max_exp; /* truncate	*/
 | |
| 	}
 | |
| 	new = buf.m1 >> (32-buf.exp);
 | |
| 	if (buf.sign)
 | |
| 		new = -new;
 | |
| done:
 | |
| 	src.__double[ss == 8] = new;
 | |
| 	return(new);
 | |
| }
 |