update math.h: const macro conformance fixes, bithack update, warning fix

[libm] / include / math.h

diff --git a/include/math.h b/include/math.h
index 67810a0..19097a5 100644 (file)
--- a/include/math.h
+++ b/include/math.h
@@ -12,17 +12,18 @@ extern "C" {
 #define __NEED___uint64_t
 #include <bits/alltypes.h>
 
-#define __MAKE_FLOAT(i) (((union { int __i; float __f; }){ .__i = i }).__f)
-
-#define NAN       __MAKE_FLOAT(0x7fc00000)
-#define INFINITY  __MAKE_FLOAT(0x7f800000)
+#if 100*__GNUC__+__GNUC_MINOR__ >= 303
+#define NAN       __builtin_nanf("")
+#define INFINITY  __builtin_inff()
+#else
+#define NAN       (0.0f/0.0f)
+#define INFINITY  1e40f
+#endif
 
 #define HUGE_VALF INFINITY
 #define HUGE_VAL  ((double)INFINITY)
 #define HUGE_VALL ((long double)INFINITY)
 
-#define MAXFLOAT  __MAKE_FLOAT(0x7f7fffff)
-
 #define MATH_ERRNO  1
 #define MATH_EXCEPT 2
 #define math_errhandling 2
@@ -40,27 +41,49 @@ int __fpclassify(double);
 int __fpclassifyf(float);
 int __fpclassifyl(long double);
 
+#define __FLOAT_BITS(f) (((union { float __f; __uint32_t __i; }){ (f) }).__i)
+#define __DOUBLE_BITS(f) (((union { double __f; __uint64_t __i; }){ (f) }).__i)
+
 #define fpclassify(x) ( \
        sizeof(x) == sizeof(float) ? __fpclassifyf(x) : \
        sizeof(x) == sizeof(double) ? __fpclassify(x) : \
        __fpclassifyl(x) )
 
-#define isinf(x)    (fpclassify(x) == FP_INFINITE)
-#define isnan(x)    (fpclassify(x) == FP_NAN)
-#define isnormal(x) (fpclassify(x) == FP_NORMAL)
-#define isfinite(x) (fpclassify(x) > FP_INFINITE)
+#define isinf(x) ( \
+       sizeof(x) == sizeof(float) ? (__FLOAT_BITS(x) & 0x7fffffff) == 0x7f800000 : \
+       sizeof(x) == sizeof(double) ? (__DOUBLE_BITS(x) & (__uint64_t)-1>>1) == (__uint64_t)0x7ff<<52 : \
+       __fpclassifyl(x) == FP_INFINITE)
+
+#define isnan(x) ( \
+       sizeof(x) == sizeof(float) ? (__FLOAT_BITS(x) & 0x7fffffff) > 0x7f800000 : \
+       sizeof(x) == sizeof(double) ? (__DOUBLE_BITS(x) & (__uint64_t)-1>>1) > (__uint64_t)0x7ff<<52 : \
+       __fpclassifyl(x) == FP_NAN)
+
+#define isnormal(x) ( \
+       sizeof(x) == sizeof(float) ? ((__FLOAT_BITS(x)+0x00800000) & 0x7fffffff) >= 0x01000000 : \
+       sizeof(x) == sizeof(double) ? ((__DOUBLE_BITS(x)+((__uint64_t)1<<52)) & (__uint64_t)-1>>1) >= (__uint64_t)1<<53 : \
+       __fpclassifyl(x) == FP_NORMAL)
+
+#define isfinite(x) ( \
+       sizeof(x) == sizeof(float) ? (__FLOAT_BITS(x) & 0x7fffffff) < 0x7f800000 : \
+       sizeof(x) == sizeof(double) ? (__DOUBLE_BITS(x) & (__uint64_t)-1>>1) < (__uint64_t)0x7ff<<52 : \
+       __fpclassifyl(x) > FP_INFINITE)
 
 int __signbit(double);
 int __signbitf(float);
 int __signbitl(long double);
 
 #define signbit(x) ( \
-       sizeof(x) == sizeof(float) ? __signbitf(x) : \
-       sizeof(x) == sizeof(double) ? __signbit(x) : \
+       sizeof(x) == sizeof(float) ? __FLOAT_BITS(x) & 0x80000000 : \
+       sizeof(x) == sizeof(double) ? __DOUBLE_BITS(x) & (__uint64_t)1<<63 : \
        __signbitl(x) )
 
 #define isunordered(x,y) (isnan((x)) ? ((void)(y),1) : isnan((y)))
-static inline int __isrel(long double __x, long double __y, int __rel)
+
+#if __STDC_VERSION__ >= 199901L
+inline
+#endif
+static int __isrel(long double __x, long double __y, int __rel)
 {
        if (isunordered(__x, __y)) return 0;
        if (__rel==-2) return __x < __y;
@@ -305,6 +328,7 @@ float       truncf(float);
 long double truncl(long double);
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
+#define MAXFLOAT        3.40282347e+38F
 #define M_E             2.7182818284590452354   /* e */
 #define M_LOG2E         1.4426950408889634074   /* log_2 e */
 #define M_LOG10E        0.43429448190325182765  /* log_10 e */