On 2023-11-16 4:52 p.m., Jeff Law wrote:
On 11/16/23 10:54, John David Anglin wrote:
Tested on hppa-unknown-linux-gnu and hppa64-hp-hpux11.11. Committed
to trunk.
This patch works around problem compiling python3.11 by improving
REG+D address handling. The change results in smaller code and
reduced register pressure.
Dave
---
hppa: Revise REG+D address support to allow long displacements before reload
In analyzing PR rtl-optimization/112415, I realized that restricting
REG+D offsets to 5-bits before reload results in very poor code and
complexities in optimizing these instructions after reload. The
general problem is long displacements are not allowed for floating
point accesses when generating PA 1.1 code. Even with PA 2.0, there
is a ELF linker bug that prevents using long displacements for
floating point loads and stores.
In the past, enabling long displacements before reload caused issues
in reload. However, there have been fixes in the handling of reloads
for floating-point accesses. This change allows long displacements
before reload and corrects a couple of issues in the constraint
handling for integer and floating-point accesses.
2023-11-16 John David Anglin <dang...@gcc.gnu.org>
gcc/ChangeLog:
PR rtl-optimization/112415
* config/pa/pa.cc (pa_legitimate_address_p): Allow 14-bit
displacements before reload. Simplify logic flow. Revise
comments.
* config/pa/pa.h (TARGET_ELF64): New define.
(INT14_OK_STRICT): Update define and comment.
* config/pa/pa64-linux.h (TARGET_ELF64): Define.
* config/pa/predicates.md (base14_operand): Don't check
alignment of short displacements.
(integer_store_memory_operand): Don't return true when
reload_in_progress is true. Remove INT_5_BITS check.
(floating_point_store_memory_operand): Don't return true when
reload_in_progress is true. Use INT14_OK_STRICT to check
whether long displacements are always okay.
I strongly suspect this is going to cause problems in the end.
I've already done what you're trying to do. It'll likely look fine for an
extended period of time, but it will almost certainly break one day.
I could happen. If it happens and can't be fixed, it's easy enough to return
false in
pa_legitimate_address_p before reload. Maybe we could add an optimization
option for this.
As it stands, the code improvement for python is significant. I don't think
f-m-o can fix things after reload.
Hopefully, Sam will test the change with various package builds on gentoo.
Debian is still on gcc-13.
I'm not seeing any obvious problems in the gcc testsuite. It needs testing on
packages that do extensive
floating point calculations.
Dave
--
John David Anglin dave.ang...@bell.net
