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authorRich Felker <dalias@aerifal.cx>2012-03-16 23:58:49 -0400
committerRich Felker <dalias@aerifal.cx>2012-03-16 23:58:49 -0400
commit2e77dc13f8bc2053642fcb136996f5f36c88c775 (patch)
treec0fc346570b01898381431c51cd7520a22c402fb /src
parent8c071f872b2844ca297275176047f8d23eec96a7 (diff)
downloadmusl-2e77dc13f8bc2053642fcb136996f5f36c88c775.tar.gz
make fma and lrint functions build without full fenv support
this is necessary to support archs where fenv is incomplete or unavailable (presently arm). fma, fmal, and the lrint family should work perfectly fine with this change; fmaf is slightly broken with respect to rounding as it depends on non-default rounding modes to do its work.
Diffstat (limited to 'src')
-rw-r--r--src/math/fma.c14
-rw-r--r--src/math/fmaf.c2
-rw-r--r--src/math/fmal.c14
-rw-r--r--src/math/lrint.c2
4 files changed, 28 insertions, 4 deletions
diff --git a/src/math/fma.c b/src/math/fma.c
index c53f3148..f44ecda7 100644
--- a/src/math/fma.c
+++ b/src/math/fma.c
@@ -199,27 +199,37 @@ double fma(double x, double y, double z)
* modes other than FE_TONEAREST are painful.
*/
if (spread < -DBL_MANT_DIG) {
+#ifdef FE_INEXACT
feraiseexcept(FE_INEXACT);
+#endif
+#ifdef FE_UNDERFLOW
if (!isnormal(z))
feraiseexcept(FE_UNDERFLOW);
+#endif
switch (oround) {
- case FE_TONEAREST:
+ default: /* FE_TONEAREST */
return (z);
+#ifdef FE_TOWARDZERO
case FE_TOWARDZERO:
if (x > 0.0 ^ y < 0.0 ^ z < 0.0)
return (z);
else
return (nextafter(z, 0));
+#endif
+#ifdef FE_DOWNWARD
case FE_DOWNWARD:
if (x > 0.0 ^ y < 0.0)
return (z);
else
return (nextafter(z, -INFINITY));
- default: /* FE_UPWARD */
+#endif
+#ifdef FE_UPWARD
+ case FE_UPWARD:
if (x > 0.0 ^ y < 0.0)
return (nextafter(z, INFINITY));
else
return (z);
+#endif
}
}
if (spread <= DBL_MANT_DIG * 2)
diff --git a/src/math/fmaf.c b/src/math/fmaf.c
index 0dccf108..cc427fb5 100644
--- a/src/math/fmaf.c
+++ b/src/math/fmaf.c
@@ -54,7 +54,9 @@ float fmaf(float x, float y, float z)
* If result is inexact, and exactly halfway between two float values,
* we need to adjust the low-order bit in the direction of the error.
*/
+#ifdef FE_TOWARDZERO
fesetround(FE_TOWARDZERO);
+#endif
volatile double vxy = xy; /* XXX work around gcc CSE bug */
double adjusted_result = vxy + z;
fesetround(FE_TONEAREST);
diff --git a/src/math/fmal.c b/src/math/fmal.c
index 200bd5a5..3944c292 100644
--- a/src/math/fmal.c
+++ b/src/math/fmal.c
@@ -194,27 +194,37 @@ long double fmal(long double x, long double y, long double z)
* modes other than FE_TONEAREST are painful.
*/
if (spread < -LDBL_MANT_DIG) {
+#ifdef FE_INEXACT
feraiseexcept(FE_INEXACT);
+#endif
+#ifdef FE_UNDERFLOW
if (!isnormal(z))
feraiseexcept(FE_UNDERFLOW);
+#endif
switch (oround) {
- case FE_TONEAREST:
+ default: /* FE_TONEAREST */
return (z);
+#ifdef FE_TOWARDZERO
case FE_TOWARDZERO:
if (x > 0.0 ^ y < 0.0 ^ z < 0.0)
return (z);
else
return (nextafterl(z, 0));
+#endif
+#ifdef FE_DOWNWARD
case FE_DOWNWARD:
if (x > 0.0 ^ y < 0.0)
return (z);
else
return (nextafterl(z, -INFINITY));
- default: /* FE_UPWARD */
+#endif
+#ifdef FE_UPWARD
+ case FE_UPWARD:
if (x > 0.0 ^ y < 0.0)
return (nextafterl(z, INFINITY));
else
return (z);
+#endif
}
}
if (spread <= LDBL_MANT_DIG * 2)
diff --git a/src/math/lrint.c b/src/math/lrint.c
index 98d58ad0..9754fa74 100644
--- a/src/math/lrint.c
+++ b/src/math/lrint.c
@@ -49,8 +49,10 @@ dtype fn(type x)
feholdexcept(&env);
d = (dtype)roundit(x);
+#if defined(FE_INVALID) && defined(FE_INEXACT)
if (fetestexcept(FE_INVALID))
feclearexcept(FE_INEXACT);
+#endif
feupdateenv(&env);
return d;
}