math: add asuint, asuint64, asfloat and asdouble
Code generation for SET_HIGH_WORD slightly changes, but it only affects
pow, otherwise the generated code is unchanged.
diff --git a/src/internal/libm.h b/src/internal/libm.h
index 6e2d190..098c705 100644
--- a/src/internal/libm.h
+++ b/src/internal/libm.h
@@ -83,73 +83,55 @@
} \
} while(0)
+#define asuint(f) ((union{float _f; uint32_t _i;}){f})._i
+#define asfloat(i) ((union{uint32_t _i; float _f;}){i})._f
+#define asuint64(f) ((union{double _f; uint64_t _i;}){f})._i
+#define asdouble(i) ((union{uint64_t _i; double _f;}){i})._f
+
/* Get two 32 bit ints from a double. */
#define EXTRACT_WORDS(hi,lo,d) \
do { \
- union {double f; uint64_t i;} __u; \
- __u.f = (d); \
- (hi) = __u.i >> 32; \
- (lo) = (uint32_t)__u.i; \
+ uint64_t __u = asuint64(d); \
+ (hi) = __u >> 32; \
+ (lo) = (uint32_t)__u; \
} while (0)
/* Get the more significant 32 bit int from a double. */
#define GET_HIGH_WORD(hi,d) \
do { \
- union {double f; uint64_t i;} __u; \
- __u.f = (d); \
- (hi) = __u.i >> 32; \
+ (hi) = asuint64(d) >> 32; \
} while (0)
/* Get the less significant 32 bit int from a double. */
#define GET_LOW_WORD(lo,d) \
do { \
- union {double f; uint64_t i;} __u; \
- __u.f = (d); \
- (lo) = (uint32_t)__u.i; \
+ (lo) = (uint32_t)asuint64(d); \
} while (0)
/* Set a double from two 32 bit ints. */
#define INSERT_WORDS(d,hi,lo) \
do { \
- union {double f; uint64_t i;} __u; \
- __u.i = ((uint64_t)(hi)<<32) | (uint32_t)(lo); \
- (d) = __u.f; \
+ (d) = asdouble(((uint64_t)(hi)<<32) | (uint32_t)(lo)); \
} while (0)
/* Set the more significant 32 bits of a double from an int. */
#define SET_HIGH_WORD(d,hi) \
-do { \
- union {double f; uint64_t i;} __u; \
- __u.f = (d); \
- __u.i &= 0xffffffff; \
- __u.i |= (uint64_t)(hi) << 32; \
- (d) = __u.f; \
-} while (0)
+ INSERT_WORDS(d, hi, (uint32_t)asuint64(d))
/* Set the less significant 32 bits of a double from an int. */
#define SET_LOW_WORD(d,lo) \
-do { \
- union {double f; uint64_t i;} __u; \
- __u.f = (d); \
- __u.i &= 0xffffffff00000000ull; \
- __u.i |= (uint32_t)(lo); \
- (d) = __u.f; \
-} while (0)
+ INSERT_WORDS(d, asuint64(d)>>32, lo)
/* Get a 32 bit int from a float. */
#define GET_FLOAT_WORD(w,d) \
do { \
- union {float f; uint32_t i;} __u; \
- __u.f = (d); \
- (w) = __u.i; \
+ (w) = asuint(d); \
} while (0)
/* Set a float from a 32 bit int. */
#define SET_FLOAT_WORD(d,w) \
do { \
- union {float f; uint32_t i;} __u; \
- __u.i = (w); \
- (d) = __u.f; \
+ (d) = asfloat(w); \
} while (0)
/* fdlibm kernel functions */