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authorTaru Karttunen <taruti@taruti.net>2011-03-30 15:46:40 +0300
committerTaru Karttunen <taruti@taruti.net>2011-03-30 15:46:40 +0300
commite5888a1ffdae813d7575f5fb02275c6bb07e5199 (patch)
treed8d51eac403f07814b9e936eed0c9a79195e2450 /sys/src/ape/lib/fmt/nan64.c
Import sources from 2011-03-30 iso image
Diffstat (limited to 'sys/src/ape/lib/fmt/nan64.c')
-rwxr-xr-xsys/src/ape/lib/fmt/nan64.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/sys/src/ape/lib/fmt/nan64.c b/sys/src/ape/lib/fmt/nan64.c
new file mode 100755
index 000000000..a02a3adb6
--- /dev/null
+++ b/sys/src/ape/lib/fmt/nan64.c
@@ -0,0 +1,76 @@
+/*
+ * 64-bit IEEE not-a-number routines.
+ * This is big/little-endian portable assuming that
+ * the 64-bit doubles and 64-bit integers have the
+ * same byte ordering.
+ */
+
+#include "nan.h"
+
+#ifdef __APPLE__
+#define _NEEDLL
+#endif
+
+typedef unsigned long long uvlong;
+typedef unsigned long ulong;
+
+#ifdef _NEEDLL
+static uvlong uvnan = 0x7FF0000000000001LL;
+static uvlong uvinf = 0x7FF0000000000000LL;
+static uvlong uvneginf = 0xFFF0000000000000LL;
+#else
+static uvlong uvnan = 0x7FF0000000000001;
+static uvlong uvinf = 0x7FF0000000000000;
+static uvlong uvneginf = 0xFFF0000000000000;
+#endif
+
+double
+__NaN(void)
+{
+ uvlong *p;
+
+ /* gcc complains about "return *(double*)&uvnan;" */
+ p = &uvnan;
+ return *(double*)p;
+}
+
+int
+__isNaN(double d)
+{
+ uvlong x;
+ double *p;
+
+ p = &d;
+ x = *(uvlong*)p;
+ return (ulong)(x>>32)==0x7FF00000 && !__isInf(d, 0);
+}
+
+double
+__Inf(int sign)
+{
+ uvlong *p;
+
+ if(sign < 0)
+ p = &uvinf;
+ else
+ p = &uvneginf;
+ return *(double*)p;
+}
+
+int
+__isInf(double d, int sign)
+{
+ uvlong x;
+ double *p;
+
+ p = &d;
+ x = *(uvlong*)p;
+ if(sign == 0)
+ return x==uvinf || x==uvneginf;
+ else if(sign > 0)
+ return x==uvinf;
+ else
+ return x==uvneginf;
+}
+
+