20060303a

1 files changed, 102 insertions, 0 deletions

diff --git a/libmath/FPcontrol-Irix.c b/libmath/FPcontrol-Irix.c
new file mode 100644
index 00000000..7a215736
--- /dev/null
+++ b/libmath/FPcontrol-Irix.c
@@ -0,0 +1,102 @@
+/* Load programs with -lfpe. See man pages for fpc and /usr/include/sigfpe.h, sys/fpu.h. */
+#include <stdlib.h>
+#include <sigfpe.h>
+#include <sys/fpu.h>
+typedef unsigned int ulong;
+#include "mathi.h"
+
+/*
+ * Irix does not permit a use handled SIGFPE since the floating point unit
+ * cannot be IEEE754 compliant without some software, so we must vector using
+ * the library
+ */
+extern	void trapFPE(unsigned exception[5], int value[2]);
+
+void
+FPinit(void)
+{
+	union fpc_csr csr;
+	int i;
+	for(i=1; i<=4; i++) {
+		sigfpe_[i].repls = _USER_DETERMINED;
+		sigfpe_[i].abort = 2;
+	}
+	handle_sigfpes(_ON,
+			_EN_UNDERFL|_EN_OVERFL|_EN_DIVZERO|_EN_INVALID,
+			trapFPE,
+			_ABORT_ON_ERROR, 0);
+}
+
+
+ulong
+getFPstatus(void)
+{
+	ulong fsr = 0;
+	union fpc_csr csr;
+	csr.fc_word = get_fpc_csr();
+	if(csr.fc_struct.se_inexact) fsr |= INEX;
+	if(csr.fc_struct.se_overflow) fsr |= OVFL;
+	if(csr.fc_struct.se_underflow) fsr |= UNFL;
+	if(csr.fc_struct.se_divide0) fsr |= ZDIV;
+	if(csr.fc_struct.se_invalid) fsr |= INVAL;
+	return fsr;
+}
+
+ulong
+FPstatus(ulong fsr, ulong mask)
+{
+	ulong old = getFPstatus();
+	union fpc_csr csr;
+	csr.fc_word = get_fpc_csr();
+	fsr = (fsr&mask) | (old&~mask);
+	csr.fc_struct.se_inexact = (fsr&INEX)?1:0;
+	csr.fc_struct.se_overflow = (fsr&OVFL)?1:0;
+	csr.fc_struct.se_underflow = (fsr&UNFL)?1:0;
+	csr.fc_struct.se_divide0 = (fsr&ZDIV)?1:0;
+	csr.fc_struct.se_invalid = (fsr&INVAL)?1:0;
+	set_fpc_csr(csr.fc_word);
+	return(old&mask);
+}
+
+ulong
+getFPcontrol(void)
+{
+	ulong fcr = 0;
+	union fpc_csr csr;
+	double junk = fabs(1.); /* avoid bug mentioned in sigfpes man page [ehg] */
+	csr.fc_word = get_fpc_csr();
+	switch(csr.fc_struct.rounding_mode){
+		case ROUND_TO_NEAREST:		fcr = RND_NR; break;
+		case ROUND_TO_MINUS_INFINITY:	fcr = RND_NINF; break;
+		case ROUND_TO_PLUS_INFINITY:	fcr = RND_PINF; break;
+		case ROUND_TO_ZERO:		fcr = RND_Z; break;
+	}
+	if(csr.fc_struct.en_inexact) fcr |= INEX;
+	if(csr.fc_struct.en_overflow) fcr |= OVFL;
+	if(csr.fc_struct.en_underflow) fcr |= UNFL;
+	if(csr.fc_struct.en_divide0) fcr |= ZDIV;
+	if(csr.fc_struct.en_invalid) fcr |= INVAL;
+	return fcr;
+}
+
+ulong
+FPcontrol(ulong fcr, ulong mask)
+{
+	ulong old = getFPcontrol();
+	union fpc_csr csr;
+	csr.fc_word = get_fpc_csr();
+	fcr = (fcr&mask) | (old&~mask);
+	csr.fc_struct.en_inexact = (fcr&INEX)?1:0;
+	csr.fc_struct.en_overflow = (fcr&OVFL)?1:0;
+	csr.fc_struct.en_underflow = (fcr&UNFL)?1:0;
+	csr.fc_struct.en_divide0 = (fcr&ZDIV)?1:0;
+	csr.fc_struct.en_invalid = (fcr&INVAL)?1:0;
+	switch(fcr&RND_MASK){
+		case RND_NR:	csr.fc_struct.rounding_mode = ROUND_TO_NEAREST; break;
+		case RND_NINF:	csr.fc_struct.rounding_mode = ROUND_TO_MINUS_INFINITY; break;
+		case RND_PINF:	csr.fc_struct.rounding_mode = ROUND_TO_PLUS_INFINITY; break;
+		case RND_Z:	csr.fc_struct.rounding_mode = ROUND_TO_ZERO; break;
+	}
+	set_fpc_csr(csr.fc_word);
+	return(old&mask);
+}