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-rw-r--r--libkern/nan-386.c69
1 files changed, 69 insertions, 0 deletions
diff --git a/libkern/nan-386.c b/libkern/nan-386.c
new file mode 100644
index 00000000..2152925a
--- /dev/null
+++ b/libkern/nan-386.c
@@ -0,0 +1,69 @@
+#include <lib9.h>
+
+#define NANEXP (2047<<20)
+#define NANMASK (2047<<20)
+#define NANSIGN (1<<31)
+
+double
+NaN(void)
+{
+ union
+ {
+ double d;
+ long x[2];
+ } a;
+
+ a.x[1] = NANEXP;
+ a.x[0] = 1;
+ return a.d;
+}
+
+int
+isNaN(double d)
+{
+ union
+ {
+ double d;
+ long x[2];
+ } a;
+
+ a.d = d;
+ if((a.x[1] & NANMASK) != NANEXP)
+ return 0;
+ return !isInf(d, 0);
+}
+
+double
+Inf(int sign)
+{
+ union
+ {
+ double d;
+ long x[2];
+ } a;
+
+ a.x[1] = NANEXP;
+ a.x[0] = 0;
+ if(sign < 0)
+ a.x[1] |= NANSIGN;
+ return a.d;
+}
+
+int
+isInf(double d, int sign)
+{
+ union
+ {
+ double d;
+ long x[2];
+ } a;
+
+ a.d = d;
+ if(a.x[0] != 0)
+ return 0;
+ if(a.x[1] == NANEXP)
+ return sign >= 0;
+ if(a.x[1] == (NANEXP|NANSIGN))
+ return sign <= 0;
+ return 0;
+}