https://gcc.gnu.org/bugzilla/show_bug.cgi?id=116007
Peter Bergner <bergner at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2024-08-02
Ever confirmed|0 |1
--- Comment #13 from Peter Bergner <bergner at gcc dot gnu.org> ---
Just as an FYI, the following error on a powerpc64le-linux
--without-long-double-128 build:
In file included from ../../../libquadmath/math/sqrtq.c:13:
../../../libquadmath/math/../../libgcc/soft-fp/quad.h:69:1: error: unable to
emulate 'TF'
69 | typedef float TFtype __attribute__ ((mode (TF)));
| ^~~~~~~
...first shows up with the following commit:
commit 481ba4fb5fce8257f5dbeb994dac2748c0237fa2 (HEAD)
Author: Jakub Jelinek <ja...@redhat.com>
AuthorDate: Tue Apr 9 08:17:25 2024 +0200
Commit: Jakub Jelinek <ja...@redhat.com>
CommitDate: Tue Apr 9 08:17:25 2024 +0200
libquadmath: Use soft-fp for sqrtq finite positive arguments [PR114623]
sqrt should be 0.5ulp precise, but the current implementation is less
precise than that.
The following patch uses the soft-fp code (like e.g. glibc for x86) for it
if possible. I didn't want to replicate the libgcc infrastructure for
choosing the right sfp-machine.h, so the patch just uses a single generic
implementation. As the code is used solely for the finite positive
arguments,
it shouldn't generate NaNs (so the exact form of canonical QNaN/SNaN is
irrelevant), and sqrt for these shouldn't produce underflows/overflows
either,
for < 1.0 arguments it always returns larger values than the argument and
for
> 1.0 smaller values than the argument.
2024-04-09 Jakub Jelinek <ja...@redhat.com>
PR libquadmath/114623
* sfp-machine.h: New file.
* math/sqrtq.c: Include from libgcc/soft-fp also soft-fp.h and
quad.h
if possible.
(USE_SOFT_FP): Define in that case.
(sqrtq): Use soft-fp based implementation for the finite positive
arguments if possible.
...which is due to the above commit code includes quad.h, and quad.h (even
before the above commit) seems to require TFmode exists, which it doesn't on a
--without-long-double-128 build.
