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simplify vasprintf implementation
[musl]
/
src
/
math
/
fma.c
diff --git
a/src/math/fma.c
b/src/math/fma.c
index
1b1c132
..
02f5c86
100644
(file)
--- a/
src/math/fma.c
+++ b/
src/math/fma.c
@@
-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;
static inline double add_adjusted(double a, double b)
{
struct dd sum;
- u
int64_t hibits, lobits
;
+ u
nion {double f; uint64_t i;} uhi, ulo
;
sum = dd_add(a, b);
if (sum.lo != 0) {
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) */
/* 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);
}
}
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;
static inline double add_and_denormalize(double a, double b, int scale)
{
struct dd sum;
- u
int64_t hibits, lobits
;
+ u
nion {double f; uint64_t i;} uhi, ulo
;
int bits_lost;
sum = dd_add(a, b);
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) {
* 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) */
/* 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);
}
}
return scalbn(sum.hi, scale);
@@
-431,12
+431,24
@@
double fma(double x, double y, double z)
/*
* There is no need to worry about double rounding in directed
* rounding modes.
/*
* There is no need to worry about double rounding in directed
* rounding modes.
- *
TODO: underflow is not
raised properly, example in downward rounding:
+ *
But underflow may not be
raised properly, example in downward rounding:
* fma(0x1.000000001p-1000, 0x1.000000001p-30, -0x1p-1066)
*/
* fma(0x1.000000001p-1000, 0x1.000000001p-30, -0x1p-1066)
*/
+ double ret;
+#if defined(FE_INEXACT) && defined(FE_UNDERFLOW)
+ int e = fetestexcept(FE_INEXACT);
+ feclearexcept(FE_INEXACT);
+#endif
fesetround(oround);
adj = r.lo + xy.lo;
fesetround(oround);
adj = r.lo + xy.lo;
- return scalbn(r.hi + adj, spread);
+ ret = scalbn(r.hi + adj, spread);
+#if defined(FE_INEXACT) && defined(FE_UNDERFLOW)
+ if (ilogb(ret) < -1022 && fetestexcept(FE_INEXACT))
+ feraiseexcept(FE_UNDERFLOW);
+ else if (e)
+ feraiseexcept(FE_INEXACT);
+#endif
+ return ret;
}
adj = add_adjusted(r.lo, xy.lo);
}
adj = add_adjusted(r.lo, xy.lo);