[PATCH v1 1/2] aarch64: Fix condition accepted by mov<GPF>cc

[Tamar Christina]

Hi Karl,

> -----Original Message-----
> From: via Sourceware Forge <forge-bot@forge-test.rdfm.org>
> Sent: 30 September 2025 13:05
> To: gcc-patches mailing list <test-list@sourceware.org>
> Cc: gcc-patches@gcc.gnu.org
> Subject: [PATCH v1 1/2] aarch64: Fix condition accepted by mov<GPF>cc
> 
> 
> From: Karl Meakin <karl.meakin@arm.com>
> 
> Apply the same fix from bc11cbff9e648fdda2798bfa2d7151d5cd164b87
> ("aarch64: Fix condition accepted by mov<ALLI>cc") to `MOV<GPF>cc`.
> Fixes ICEs when compiling code such as `cmpbr-4.c` with `+cmpbr`.
> 
> gcc/ChangeLog:
> 
> 	* config/aarch64/aarch64.md(mov<GPF>cc): Accept MODE_CC
> 	conditions directly; reject QI/HImode conditions.
> 
> gcc/testsuite/ChangeLog:
> 
> 	* gcc.target/aarch64/cmpbr-4.c: New test.

Would we not have the same problem with the other expanders that
seem to have the same boilerplate code? Like

"<neg_not_op><mode>cc" and "mov<GPF:mode><GPI:mode>cc"?

These patterns look weird in that they accept a wide range of values
and then restricts them in the expand pattern.

I think instead the checks should be moved into a new predicate
"aarch64_comparison_operator_cc" and then validation done
there similarly to how we do with aarch64_comparison_operation.

Then the predicate can be used in the other functions and also
simplifies the expand patterns.

Thanks,
Tamar

> ---
>  gcc/config/aarch64/aarch64.md              | 16 +++++++++++-----
>  gcc/testsuite/gcc.target/aarch64/cmpbr-4.c | 12 ++++++++++++
>  2 files changed, 23 insertions(+), 5 deletions(-)
>  create mode 100644 gcc/testsuite/gcc.target/aarch64/cmpbr-4.c