Shift the NaN fraction to a canonical position, much like we do
for the fraction of normal numbers. Immediately, this simplifies
the float-to-float conversion. Later, this will facilitate
manipulation of NaNs within the shared code paths.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
fpu/softfloat.c | 13 ++++++-------
1 file changed, 6 insertions(+), 7 deletions(-)
diff --git a/fpu/softfloat.c b/fpu/softfloat.c
index 5e4982b035..df377b6314 100644
--- a/fpu/softfloat.c
+++ b/fpu/softfloat.c
@@ -329,10 +329,11 @@ static FloatParts canonicalize(FloatParts part, const
FloatFmt *parm,
if (part.frac == 0) {
part.cls = float_class_inf;
} else {
+ part.frac <<= parm->frac_shift;
#ifdef NO_SIGNALING_NANS
part.cls = float_class_qnan;
#else
- int64_t msb = part.frac << (parm->frac_shift + 2);
+ int64_t msb = part.frac << 2;
if ((msb < 0) == status->snan_bit_is_one) {
part.cls = float_class_snan;
} else {
@@ -498,6 +499,7 @@ static FloatParts round_canonical(FloatParts p,
float_status *s,
case float_class_qnan:
case float_class_snan:
exp = exp_max;
+ frac >>= parm->frac_shift;
break;
default:
@@ -1264,13 +1266,10 @@ static FloatParts float_to_float(FloatParts a,
}
/*
- * Our only option now is to "re-pack" the NaN. As the
- * canonilization process doesn't mess with fraction bits for
- * NaNs we do it all here. We also reset a.exp to the
- * destination format exp_max as the maybe_silence_nan code
- * assumes it is correct (which is would be for non-conversions).
+ * Reset a.exp to the destination format exp_max as
+ * the maybe_silence_nan code assumes it is correct
+ * (which it would be for non-conversions).
*/
- a.frac = a.frac << (64 - srcf->frac_size) >> (64 - dstf->frac_size);
a.exp = dstf->exp_max;
a.cls = float_class_msnan;
}
--
2.17.0
