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authorPikalaxALT <pikalaxalt@gmail.com>2017-12-15 09:38:53 -0500
committerPikalaxALT <pikalaxalt@gmail.com>2017-12-15 09:39:34 -0500
commitf95a4a932476be2ba99e2fd081e8d2bc6ea12813 (patch)
tree75f67192cb2d7b7b575c94edda318e475239b63c /newlib/libm/common/sf_logb.c
parentf60aca96985e68c7d8a52eb7bc955fb80e132f73 (diff)
Import newlib and create makefile
Diffstat (limited to 'newlib/libm/common/sf_logb.c')
-rw-r--r--newlib/libm/common/sf_logb.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/newlib/libm/common/sf_logb.c b/newlib/libm/common/sf_logb.c
new file mode 100644
index 0000000..6e67637
--- /dev/null
+++ b/newlib/libm/common/sf_logb.c
@@ -0,0 +1,48 @@
+/* sf_logb.c -- float version of s_logb.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#include "fdlibm.h"
+
+#ifdef __STDC__
+ float logbf(float x)
+#else
+ float logbf(x)
+ float x;
+#endif
+{
+ __int32_t ix;
+ GET_FLOAT_WORD(ix,x);
+ ix &= 0x7fffffff; /* high |x| */
+ if(ix==0) return (float)-1.0/fabsf(x);
+ if(ix>=0x7f800000) return x*x;
+ if((ix>>=23)==0) /* IEEE 754 logb */
+ return -126.0;
+ else
+ return (float) (ix-127);
+}
+
+#ifdef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+ double logb(double x)
+#else
+ double logb(x)
+ double x;
+#endif
+{
+ return (double) logbf((float) x);
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */