Hi!
The ia32 _BitInt support revealed a bug in floatbitint?d.c.
As can be even guessed from how the code is written in the loop,
the intention was to set inexact to non-zero whenever the remainder
after division wasn't zero, but I've ended up just checking whether
the 2 least significant limbs of the remainder were non-zero.
Now, in the dfp/bitint-4.c test in one case the remainder happens
to have least significant 64 bits zero and then the higher limbs are
non-zero; with 32-bit limbs that means 2 least significant limbs are zero
and so the code acted as if it was exactly divisible.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux
(including the _BitInt enablement there), ok for trunk?
2024-02-10 Jakub Jelinek <ja...@redhat.com>
* soft-fp/floatbitintdd.c (__bid_floatbitintdd): Or in all remainder
limbs into inexact rather than just first two.
* soft-fp/floatbitintsd.c (__bid_floatbitintsd): Likewise.
* soft-fp/floatbitinttd.c (__bid_floatbitinttd): Likewise.
--- libgcc/soft-fp/floatbitintdd.c.jj 2024-02-09 17:11:47.095675716 +0100
+++ libgcc/soft-fp/floatbitintdd.c 2024-02-09 18:22:25.786674139 +0100
@@ -114,7 +114,7 @@ __bid_floatbitintdd (const UBILtype *i,
buf + BITINT_END (q_limbs - 1, 0), q_limbs);
inexact = buf[q_limbs + pow10_limbs];
for (j = 1; j < pow10_limbs; ++j)
- inexact |= buf[q_limbs + pow10_limbs + 1];
+ inexact |= buf[q_limbs + pow10_limbs + j];
}
else
{
--- libgcc/soft-fp/floatbitintsd.c.jj 2023-09-06 17:34:04.978510447 +0200
+++ libgcc/soft-fp/floatbitintsd.c 2024-02-09 18:21:50.949158569 +0100
@@ -113,7 +113,7 @@ __bid_floatbitintsd (const UBILtype *i,
buf + BITINT_END (q_limbs - 1, 0), q_limbs);
inexact = buf[q_limbs + pow10_limbs];
for (j = 1; j < pow10_limbs; ++j)
- inexact |= buf[q_limbs + pow10_limbs + 1];
+ inexact |= buf[q_limbs + pow10_limbs + j];
}
else
{
--- libgcc/soft-fp/floatbitinttd.c.jj 2024-02-09 17:14:17.485578556 +0100
+++ libgcc/soft-fp/floatbitinttd.c 2024-02-09 18:21:34.409388566 +0100
@@ -113,7 +113,7 @@ __bid_floatbitinttd (const UBILtype *i,
buf + BITINT_END (q_limbs - 1, 0), q_limbs);
inexact = buf[q_limbs + pow10_limbs];
for (j = 1; j < pow10_limbs; ++j)
- inexact |= buf[q_limbs + pow10_limbs + 1];
+ inexact |= buf[q_limbs + pow10_limbs + j];
}
else
{
Jakub
