* libc/include/machine/ieeefp.h: Comment about new configuration

	macros _FLT_LARGEST_EXPONENT_IS_NORMAL and _FLT_NO_DENORMALS.
	* libm/common/fdlib.h: Define new macros for testing floats.
	* libm/common/sf_*: Use them.
	* libm/math/ef_*: Likewise.
	* libm/math/sf_*: Likewise.

1 files changed, 14 insertions, 8 deletions

diff --git a/newlib/libm/common/sf_scalbn.c b/newlib/libm/common/sf_scalbn.c
index fb67c7816..700060010 100644
--- a/newlib/libm/common/sf_scalbn.c
+++ b/newlib/libm/common/sf_scalbn.c
@@ -15,6 +15,7 @@
 
 #include "fdlibm.h"
 #include <limits.h>
+#include <float.h>
 
 #if INT_MAX > 50000
 #define OVERFLOW_INT 50000
@@ -40,25 +41,30 @@ tiny   = 1.0e-30;
 #endif
 {
 	__int32_t  k,ix;
+	__uint32_t hx;
+
 	GET_FLOAT_WORD(ix,x);
-        k = (ix&0x7f800000)>>23;		/* extract exponent */
-        if (k==0) {				/* 0 or subnormal x */
-            if ((ix&0x7fffffff)==0) return x; /* +-0 */
+	hx = ix&0x7fffffff;
+        k = hx>>23;		/* extract exponent */
+	if (FLT_UWORD_IS_ZERO(hx))
+	    return x;
+        if (!FLT_UWORD_IS_FINITE(hx))
+	    return x+x;		/* NaN or Inf */
+        if (FLT_UWORD_IS_SUBNORMAL(hx)) {
 	    x *= two25;
 	    GET_FLOAT_WORD(ix,x);
 	    k = ((ix&0x7f800000)>>23) - 25; 
             if (n< -50000) return tiny*x; 	/*underflow*/
-	    }
-        if (k==0xff) return x+x;		/* NaN or Inf */
+        }
         k = k+n; 
-        if (k >  0xfe) return huge*copysignf(huge,x); /* overflow  */
+        if (k > FLT_LARGEST_EXP) return huge*copysignf(huge,x); /* overflow  */
         if (k > 0) 				/* normal result */
 	    {SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23)); return x;}
-        if (k <= -25) {
+        if (k < FLT_SMALLEST_EXP) {
             if (n > OVERFLOW_INT) 	/* in case integer overflow in n+k */
 		return huge*copysignf(huge,x);	/*overflow*/
 	    else return tiny*copysignf(tiny,x);	/*underflow*/
-       }
+        }
         k += 25;				/* subnormal result */
 	SET_FLOAT_WORD(x,(ix&0x807fffff)|(k<<23));
         return x*twom25;