xref: /inferno-os/libmath/FPcontrol-DragonFly.c (revision ce3f4532f3f68d5c3419c4581504faff3a1d2820)
1*07f684ffSforsyth #include "lib9.h"
2*07f684ffSforsyth #include "mathi.h"
3*07f684ffSforsyth 
4*07f684ffSforsyth void
FPinit(void)5*07f684ffSforsyth FPinit(void)
6*07f684ffSforsyth {
7*07f684ffSforsyth 	setfsr(0);	/* Clear pending exceptions */
8*07f684ffSforsyth 	setfcr(FPPDBL|FPRNR|FPINVAL|FPZDIV|FPUNFL|FPOVFL);
9*07f684ffSforsyth }
10*07f684ffSforsyth 
11*07f684ffSforsyth ulong
getFPstatus(void)12*07f684ffSforsyth getFPstatus(void)
13*07f684ffSforsyth {
14*07f684ffSforsyth 	ulong fsr = 0, fsr9 = getfsr();
15*07f684ffSforsyth 	/* on specific machines, could be table lookup */
16*07f684ffSforsyth 	if(fsr9&FPAINEX) fsr |= INEX;
17*07f684ffSforsyth 	if(fsr9&FPAOVFL) fsr |= OVFL;
18*07f684ffSforsyth 	if(fsr9&FPAUNFL) fsr |= UNFL;
19*07f684ffSforsyth 	if(fsr9&FPAZDIV) fsr |= ZDIV;
20*07f684ffSforsyth 	if(fsr9&FPAINVAL) fsr |= INVAL;
21*07f684ffSforsyth 	return fsr;
22*07f684ffSforsyth }
23*07f684ffSforsyth 
24*07f684ffSforsyth ulong
FPstatus(ulong fsr,ulong mask)25*07f684ffSforsyth FPstatus(ulong fsr, ulong mask)
26*07f684ffSforsyth {
27*07f684ffSforsyth 	ulong fsr9 = 0;
28*07f684ffSforsyth 	ulong old = getFPstatus();
29*07f684ffSforsyth 	fsr = (fsr&mask) | (old&~mask);
30*07f684ffSforsyth 	if(fsr&INEX) fsr9 |= FPAINEX;
31*07f684ffSforsyth 	if(fsr&OVFL) fsr9 |= FPAOVFL;
32*07f684ffSforsyth 	if(fsr&UNFL) fsr9 |= FPAUNFL;
33*07f684ffSforsyth 	if(fsr&ZDIV) fsr9 |= FPAZDIV;
34*07f684ffSforsyth 	if(fsr&INVAL) fsr9 |= FPAINVAL;
35*07f684ffSforsyth 	setfsr(fsr9);
36*07f684ffSforsyth 	return(old&mask);
37*07f684ffSforsyth }
38*07f684ffSforsyth 
39*07f684ffSforsyth ulong
getFPcontrol(void)40*07f684ffSforsyth getFPcontrol(void)
41*07f684ffSforsyth {
42*07f684ffSforsyth 	ulong fcr = 0, fcr9 = getfcr();
43*07f684ffSforsyth 	switch(fcr9&FPRMASK){
44*07f684ffSforsyth 		case FPRNR:	fcr = RND_NR; break;
45*07f684ffSforsyth 		case FPRNINF:	fcr = RND_NINF; break;
46*07f684ffSforsyth 		case FPRPINF:	fcr = RND_PINF; break;
47*07f684ffSforsyth 		case FPRZ:	fcr = RND_Z; break;
48*07f684ffSforsyth 	}
49*07f684ffSforsyth 	if(fcr9&FPINEX) fcr |= INEX;
50*07f684ffSforsyth 	if(fcr9&FPOVFL) fcr |= OVFL;
51*07f684ffSforsyth 	if(fcr9&FPUNFL) fcr |= UNFL;
52*07f684ffSforsyth 	if(fcr9&FPZDIV) fcr |= ZDIV;
53*07f684ffSforsyth 	if(fcr9&FPINVAL) fcr |= INVAL;
54*07f684ffSforsyth 	return fcr;
55*07f684ffSforsyth }
56*07f684ffSforsyth 
57*07f684ffSforsyth ulong
FPcontrol(ulong fcr,ulong mask)58*07f684ffSforsyth FPcontrol(ulong fcr, ulong mask)
59*07f684ffSforsyth {
60*07f684ffSforsyth 	ulong fcr9 = FPPDBL;
61*07f684ffSforsyth 	ulong old = getFPcontrol();
62*07f684ffSforsyth 	fcr = (fcr&mask) | (old&~mask);
63*07f684ffSforsyth 	if(fcr&INEX) fcr9 |= FPINEX;
64*07f684ffSforsyth 	if(fcr&OVFL) fcr9 |= FPOVFL;
65*07f684ffSforsyth 	if(fcr&UNFL) fcr9 |= FPUNFL;
66*07f684ffSforsyth 	if(fcr&ZDIV) fcr9 |= FPZDIV;
67*07f684ffSforsyth 	if(fcr&INVAL) fcr9 |= FPINVAL;
68*07f684ffSforsyth 	switch(fcr&RND_MASK){
69*07f684ffSforsyth 		case RND_NR:	fcr9 |= FPRNR; break;
70*07f684ffSforsyth 		case RND_NINF:	fcr9 |= FPRNINF; break;
71*07f684ffSforsyth 		case RND_PINF:	fcr9 |= FPRPINF; break;
72*07f684ffSforsyth 		case RND_Z:	fcr9 |= FPRZ; break;
73*07f684ffSforsyth 	}
74*07f684ffSforsyth 	setfcr(fcr9);
75*07f684ffSforsyth 	return(old&mask);
76*07f684ffSforsyth }
77*07f684ffSforsyth 
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