xref: /inferno-os/libmath/FPcontrol-MacOSX.c (revision 35b4355d0f9558798dab6e80d69a321826edc319)
1 #include "lib9.h"
2 #include "mathi.h"
3 
4 #include <stdio.h>
5 
6 void
7 FPinit(void)
8 {
9 	ulong fcr9 = FPPDBL|FPRNR|FPINVAL|FPZDIV|FPUNFL|FPOVFL;
10 	setfsr(0);	/* Clear pending exceptions */
11 	setfcr(fcr9);
12 }
13 
14 ulong
15 getFPstatus(void)
16 {
17 	ulong fsr = 0, fsr9 = getfsr();
18 	/* on specific machines, could be table lookup */
19 	if(fsr9&FPAINEX) fsr |= INEX;
20 	if(fsr9&FPAOVFL) fsr |= OVFL;
21 	if(fsr9&FPAUNFL) fsr |= UNFL;
22 	if(fsr9&FPAZDIV) fsr |= ZDIV;
23 	if(fsr9&FPAINVAL) fsr |= INVAL;
24 	return fsr;
25 }
26 
27 ulong
28 FPstatus(ulong fsr, ulong mask)
29 {
30 	ulong fsr9 = 0;
31 	ulong old = getFPstatus();
32 	fsr = (fsr&mask) | (old&~mask);
33 	if(fsr&INEX) fsr9 |= FPAINEX;
34 	if(fsr&OVFL) fsr9 |= FPAOVFL;
35 	if(fsr&UNFL) fsr9 |= FPAUNFL;
36 	if(fsr&ZDIV) fsr9 |= FPAZDIV;
37 	if(fsr&INVAL) fsr9 |= FPAINVAL;
38 	setfsr(fsr9);
39 	return(old&mask);
40 }
41 
42 ulong
43 getFPcontrol(void)
44 {
45 	ulong fcr = 0, fcr9 = getfcr();
46 	switch(fcr9&FPRMASK){
47 		case FPRNR:	fcr = RND_NR; break;
48 		case FPRNINF:	fcr = RND_NINF; break;
49 		case FPRPINF:	fcr = RND_PINF; break;
50 		case FPRZ:	fcr = RND_Z; break;
51 	}
52 	if(fcr9&FPINEX) fcr |= INEX;
53 	if(fcr9&FPOVFL) fcr |= OVFL;
54 	if(fcr9&FPUNFL) fcr |= UNFL;
55 	if(fcr9&FPZDIV) fcr |= ZDIV;
56 	if(fcr9&FPINVAL) fcr |= INVAL;
57 	return fcr;
58 }
59 
60 ulong
61 FPcontrol(ulong fcr, ulong mask)
62 {
63 	ulong fcr9 = FPPDBL;
64 	ulong old = getFPcontrol();
65 	fcr = (fcr&mask) | (old&~mask);
66 	if(fcr&INEX) fcr9 |= FPINEX;
67 	if(fcr&OVFL) fcr9 |= FPOVFL;
68 	if(fcr&UNFL) fcr9 |= FPUNFL;
69 	if(fcr&ZDIV) fcr9 |= FPZDIV;
70 	if(fcr&INVAL) fcr9 |= FPINVAL;
71 	switch(fcr&RND_MASK){
72 		case RND_NR:	fcr9 |= FPRNR; break;
73 		case RND_NINF:	fcr9 |= FPRNINF; break;
74 		case RND_PINF:	fcr9 |= FPRPINF; break;
75 		case RND_Z:	fcr9 |= FPRZ; break;
76 	}
77 	setfcr(fcr9);
78 	return(old&mask);
79 }
80