xref: /inferno-os/libmath/FPcontrol-Inferno.c (revision 37da2899f40661e3e9631e497da8dc59b971cbd0)
1*37da2899SCharles.Forsyth #include "lib9.h"
2*37da2899SCharles.Forsyth #include "mathi.h"
3*37da2899SCharles.Forsyth 
4*37da2899SCharles.Forsyth void
FPinit(void)5*37da2899SCharles.Forsyth FPinit(void)
6*37da2899SCharles.Forsyth {
7*37da2899SCharles.Forsyth 	ulong fcr9 = FPPDBL|FPRNR|FPINVAL|FPZDIV|FPUNFL|FPOVFL;
8*37da2899SCharles.Forsyth 	setfcr(fcr9);
9*37da2899SCharles.Forsyth }
10*37da2899SCharles.Forsyth 
11*37da2899SCharles.Forsyth ulong
getFPstatus(void)12*37da2899SCharles.Forsyth getFPstatus(void)
13*37da2899SCharles.Forsyth {
14*37da2899SCharles.Forsyth 	ulong fsr = 0, fsr9 = getfsr();
15*37da2899SCharles.Forsyth 	/* on specific machines, could be table lookup */
16*37da2899SCharles.Forsyth 	if(fsr9&FPAINEX) fsr |= INEX;
17*37da2899SCharles.Forsyth 	if(fsr9&FPAOVFL) fsr |= OVFL;
18*37da2899SCharles.Forsyth 	if(fsr9&FPAUNFL) fsr |= UNFL;
19*37da2899SCharles.Forsyth 	if(fsr9&FPAZDIV) fsr |= ZDIV;
20*37da2899SCharles.Forsyth 	if(fsr9&FPAINVAL) fsr |= INVAL;
21*37da2899SCharles.Forsyth 	return fsr;
22*37da2899SCharles.Forsyth }
23*37da2899SCharles.Forsyth 
24*37da2899SCharles.Forsyth ulong
FPstatus(ulong fsr,ulong mask)25*37da2899SCharles.Forsyth FPstatus(ulong fsr, ulong mask)
26*37da2899SCharles.Forsyth {
27*37da2899SCharles.Forsyth 	ulong fsr9 = 0;
28*37da2899SCharles.Forsyth 	ulong old = getFPstatus();
29*37da2899SCharles.Forsyth 	fsr = (fsr&mask) | (old&~mask);
30*37da2899SCharles.Forsyth 	if(fsr&INEX) fsr9 |= FPAINEX;
31*37da2899SCharles.Forsyth 	if(fsr&OVFL) fsr9 |= FPAOVFL;
32*37da2899SCharles.Forsyth 	if(fsr&UNFL) fsr9 |= FPAUNFL;
33*37da2899SCharles.Forsyth 	if(fsr&ZDIV) fsr9 |= FPAZDIV;
34*37da2899SCharles.Forsyth 	if(fsr&INVAL) fsr9 |= FPAINVAL;
35*37da2899SCharles.Forsyth 	setfsr(fsr9);
36*37da2899SCharles.Forsyth 	return(old&mask);
37*37da2899SCharles.Forsyth }
38*37da2899SCharles.Forsyth 
39*37da2899SCharles.Forsyth ulong
getFPcontrol(void)40*37da2899SCharles.Forsyth getFPcontrol(void)
41*37da2899SCharles.Forsyth {
42*37da2899SCharles.Forsyth 	ulong fcr = 0, fcr9 = getfcr();
43*37da2899SCharles.Forsyth 	switch(fcr9&FPRMASK){
44*37da2899SCharles.Forsyth 		case FPRNR:	fcr = RND_NR; break;
45*37da2899SCharles.Forsyth 		case FPRNINF:	fcr = RND_NINF; break;
46*37da2899SCharles.Forsyth 		case FPRPINF:	fcr = RND_PINF; break;
47*37da2899SCharles.Forsyth 		case FPRZ:	fcr = RND_Z; break;
48*37da2899SCharles.Forsyth 	}
49*37da2899SCharles.Forsyth 	if(fcr9&FPINEX) fcr |= INEX;
50*37da2899SCharles.Forsyth 	if(fcr9&FPOVFL) fcr |= OVFL;
51*37da2899SCharles.Forsyth 	if(fcr9&FPUNFL) fcr |= UNFL;
52*37da2899SCharles.Forsyth 	if(fcr9&FPZDIV) fcr |= ZDIV;
53*37da2899SCharles.Forsyth 	if(fcr9&FPINVAL) fcr |= INVAL;
54*37da2899SCharles.Forsyth 	return fcr;
55*37da2899SCharles.Forsyth }
56*37da2899SCharles.Forsyth 
57*37da2899SCharles.Forsyth ulong
FPcontrol(ulong fcr,ulong mask)58*37da2899SCharles.Forsyth FPcontrol(ulong fcr, ulong mask)
59*37da2899SCharles.Forsyth {
60*37da2899SCharles.Forsyth 	ulong fcr9 = FPPDBL;
61*37da2899SCharles.Forsyth 	ulong old = getFPcontrol();
62*37da2899SCharles.Forsyth 	fcr = (fcr&mask) | (old&~mask);
63*37da2899SCharles.Forsyth 	if(fcr&INEX) fcr9 |= FPINEX;
64*37da2899SCharles.Forsyth 	if(fcr&OVFL) fcr9 |= FPOVFL;
65*37da2899SCharles.Forsyth 	if(fcr&UNFL) fcr9 |= FPUNFL;
66*37da2899SCharles.Forsyth 	if(fcr&ZDIV) fcr9 |= FPZDIV;
67*37da2899SCharles.Forsyth 	if(fcr&INVAL) fcr9 |= FPINVAL;
68*37da2899SCharles.Forsyth 	switch(fcr&RND_MASK){
69*37da2899SCharles.Forsyth 		case RND_NR:	fcr9 |= FPRNR; break;
70*37da2899SCharles.Forsyth 		case RND_NINF:	fcr9 |= FPRNINF; break;
71*37da2899SCharles.Forsyth 		case RND_PINF:	fcr9 |= FPRPINF; break;
72*37da2899SCharles.Forsyth 		case RND_Z:	fcr9 |= FPRZ; break;
73*37da2899SCharles.Forsyth 	}
74*37da2899SCharles.Forsyth 	setfcr(fcr9);
75*37da2899SCharles.Forsyth 	return(old&mask);
76*37da2899SCharles.Forsyth }
77*37da2899SCharles.Forsyth 
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