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math: remove *_WORD64 macros from libm.h

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only fma used these macros and the explicit union is clearer
This commit is contained in:
Szabolcs Nagy 2013-09-04 16:39:41 +00:00
parent 94a3d13ae6
commit 63b9cc7773
2 changed files with 13 additions and 29 deletions
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16
src/internal/libm.h
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@ -80,14 +80,6 @@ do { \
(lo) = (uint32_t)__u.bits; \
} while (0)
/* Get a 64 bit int from a double. */
#define EXTRACT_WORD64(i,d) \
do { \
union dshape __u; \
__u.value = (d); \
(i) = __u.bits; \
} while (0)
/* Get the more significant 32 bit int from a double. */
#define GET_HIGH_WORD(i,d) \
do { \
@ -112,14 +104,6 @@ do { \
(d) = __u.value; \
} while (0)
/* Set a double from a 64 bit int. */
#define INSERT_WORD64(d,i) \
do { \
union dshape __u; \
__u.bits = (i); \
(d) = __u.value; \
} while (0)
/* Set the more significant 32 bits of a double from an int. */
#define SET_HIGH_WORD(d,hi) \
do { \

26
src/math/fma.c
View File

@ -232,16 +232,16 @@ static inline struct dd dd_add(double a, double b)
static inline double add_adjusted(double a, double b)
{
struct dd sum;
uint64_t hibits, lobits;
union {double f; uint64_t i;} uhi, ulo;
sum = dd_add(a, b);
if (sum.lo != 0) {
EXTRACT_WORD64(hibits, sum.hi);
if ((hibits & 1) == 0) {
uhi.f = sum.hi;
if ((uhi.i & 1) == 0) {
/* hibits += (int)copysign(1.0, sum.hi * sum.lo) */
EXTRACT_WORD64(lobits, sum.lo);
hibits += 1 - ((hibits ^ lobits) >> 62);
INSERT_WORD64(sum.hi, hibits);
ulo.f = sum.lo;
uhi.i += 1 - ((uhi.i ^ ulo.i) >> 62);
sum.hi = uhi.f;
}
}
return (sum.hi);
@ -255,7 +255,7 @@ static inline double add_adjusted(double a, double b)
static inline double add_and_denormalize(double a, double b, int scale)
{
struct dd sum;
uint64_t hibits, lobits;
union {double f; uint64_t i;} uhi, ulo;
int bits_lost;
sum = dd_add(a, b);
@ -271,13 +271,13 @@ static inline double add_and_denormalize(double a, double b, int scale)
* break the ties manually.
*/
if (sum.lo != 0) {
EXTRACT_WORD64(hibits, sum.hi);
bits_lost = -((int)(hibits >> 52) & 0x7ff) - scale + 1;
if (bits_lost != 1 ^ (int)(hibits & 1)) {
uhi.f = sum.hi;
bits_lost = -((int)(uhi.i >> 52) & 0x7ff) - scale + 1;
if (bits_lost != 1 ^ (int)(uhi.i & 1)) {
/* hibits += (int)copysign(1.0, sum.hi * sum.lo) */
EXTRACT_WORD64(lobits, sum.lo);
hibits += 1 - (((hibits ^ lobits) >> 62) & 2);
INSERT_WORD64(sum.hi, hibits);
ulo.f = sum.lo;
uhi.i += 1 - (((uhi.i ^ ulo.i) >> 62) & 2);
sum.hi = uhi.f;
}
}
return scalbn(sum.hi, scale);