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authorrsc <devnull@localhost>2004-02-29 22:11:15 +0000
committerrsc <devnull@localhost>2004-02-29 22:11:15 +0000
commit91c13e54b5d631b65e2f8344d5e0abd058f78ba1 (patch)
tree81d77fc6a74f182543603032462e865e34e43335 /src/lib9/fmt/nan64.c
parent5a8e63b2f016735364d17866d5e2bcb35d20c78b (diff)
downloadplan9port-91c13e54b5d631b65e2f8344d5e0abd058f78ba1.tar.gz
plan9port-91c13e54b5d631b65e2f8344d5e0abd058f78ba1.zip
Move utf, fmt. Small header file changes.
Diffstat (limited to 'src/lib9/fmt/nan64.c')
-rw-r--r--src/lib9/fmt/nan64.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/src/lib9/fmt/nan64.c b/src/lib9/fmt/nan64.c
new file mode 100644
index 00000000..a02a3adb
--- /dev/null
+++ b/src/lib9/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;
+}
+
+