Floating point support functions

lib/math/Makefile.in

@@ -9,6 +9,7 @@ libc_FILES=" \
 	atan.c \
 	atan2.c \
 	ceil.c \
+	compare.c \
 	exp.c \
 	fabs.c \
 	floor.c \

lib/math/compare.c

@@ -0,0 +1,39 @@
+#include <assert.h>
+#include <math.h>
+
+/* functions missing here are architecture-specific and are in i386/float */
+
+int isfinite(double x)
+{
+	/* return value based on classification */
+	switch (fpclassify(x))
+	{
+		case FP_INFINITE:
+		case FP_NAN:
+			return 0;
+
+		case FP_NORMAL:
+		case FP_SUBNORMAL:
+		case FP_ZERO:
+			return 1;
+	}
+
+	/* if we get here, fpclassify is buggy */
+	assert(0);
+	return -1;
+}
+
+int isinf(double x)
+{
+	return fpclassify(x) == FP_INFINITE;
+}
+
+int isnan(double x)
+{
+	return fpclassify(x) == FP_NAN;
+}
+
+int isnormal(double x)
+{
+	return fpclassify(x) == FP_NORMAL;
+}

lib/math/hugeval.c

@@ -9,7 +9,7 @@
 #include	<math.h>
 
 double
-__huge_val(void)
+__infinity(void)
 {
 #if (CHIP == INTEL)
 	static unsigned char ieee_infinity[] = { 
@@ -21,3 +21,18 @@ __huge_val(void)
 	return 1.0e+1000;	/* This will generate a warning */
 #endif
 }
+
+double
+__qnan(void)
+{
+#if (CHIP == INTEL)
+	static unsigned char ieee_qnan[] = { 
+		0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x7f };
+
+	assert(sizeof(double) == sizeof(ieee_qnan));
+	return *(double *) ieee_qnan;
+#else
+#error QNaN not defined on this architecture
+#endif
+}
+

lib/math/localmath.h

@@ -3,6 +3,8 @@
  */
 /* $Header$ */
 
+#define __IsNan isnan
+
 /* some constants (Hart & Cheney) */
 #define	M_PI		3.14159265358979323846264338327950288
 #define	M_2PI		6.28318530717958647692528676655900576

lib/math/sqrt.c

@@ -9,6 +9,7 @@
 #include	<math.h>
 #include	<float.h>
 #include	<errno.h>
+#include	"localmath.h"
 
 #define NITER	5