plan9port

fork of plan9port with libvec, libstr and libsdb
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fpformat.c (1627B)


      1 #include <u.h>
      2 #include <libc.h>
      3 #include <bio.h>
      4 #include <mach.h>
      5 
      6 /*
      7  *	Format floating point registers
      8  *
      9  *	Register codes in format field:
     10  *	'X' - print as 32-bit hexadecimal value
     11  *	'F' - 64-bit double register when modif == 'F'; else 32-bit single reg
     12  *	'f' - 32-bit ieee float
     13  *	'8' - big endian 80-bit ieee extended float
     14  *	'3' - little endian 80-bit ieee extended float with hole in bytes 8&9
     15  */
     16 int
     17 fpformat(Map *map, Regdesc *rp, char *buf, uint n, uint modif)
     18 {
     19 	char reg[12];
     20 	u32int r;
     21 
     22 	switch(rp->format)
     23 	{
     24 	case 'X':
     25 		if (get4(map, rp->offset, &r) < 0)
     26 			return -1;
     27 		snprint(buf, n, "%lux", r);
     28 		break;
     29 	case 'F':	/* first reg of double reg pair */
     30 		if (modif == 'F')
     31 		if ((rp->format=='F') || (((rp+1)->flags&RFLT) && (rp+1)->format == 'f')) {
     32 			if (get1(map, rp->offset, (uchar *)reg, 8) < 0)
     33 				return -1;
     34 			mach->ftoa64(buf, n, reg);
     35 			if (rp->format == 'F')
     36 				return 1;
     37 			return 2;
     38 		}
     39 			/* treat it like 'f' */
     40 		if (get1(map, rp->offset, (uchar *)reg, 4) < 0)
     41 			return -1;
     42 		mach->ftoa32(buf, n, reg);
     43 		break;
     44 	case 'f':	/* 32 bit float */
     45 		if (get1(map, rp->offset, (uchar *)reg, 4) < 0)
     46 			return -1;
     47 		mach->ftoa32(buf, n, reg);
     48 		break;
     49 	case '3':	/* little endian ieee 80 with hole in bytes 8&9 */
     50 		if (get1(map, rp->offset, (uchar *)reg, 10) < 0)
     51 			return -1;
     52 		memmove(reg+10, reg+8, 2);	/* open hole */
     53 		memset(reg+8, 0, 2);		/* fill it */
     54 		leieeeftoa80(buf, n, reg);
     55 		break;
     56 	case '8':	/* big-endian ieee 80 */
     57 		if (get1(map, rp->offset, (uchar *)reg, 10) < 0)
     58 			return -1;
     59 		beieeeftoa80(buf, n, reg);
     60 		break;
     61 	default:	/* unknown */
     62 		break;
     63 	}
     64 	return 1;
     65 }