initial commit, 4.5 stable

thirdparty/sdl/libm/s_isinf.c

@@ -0,0 +1,24 @@
+#include "SDL_internal.h"
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Changed to return -1 for -Inf by Ulrich Drepper <drepper@cygnus.com>.
+ * Public domain.
+ */
+
+/*
+ * isinf(x) returns 1 is x is inf, -1 if x is -inf, else 0;
+ * no branching!
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+int __isinf(double x)
+{
+	int32_t hx,lx;
+	EXTRACT_WORDS(hx,lx,x);
+	lx |= (hx & 0x7fffffff) ^ 0x7ff00000;
+	lx |= -lx;
+	return ~(lx >> 31) & (hx >> 30);
+}
+libm_hidden_def(__isinf)