public inbox for gcc-bugs@sourceware.org
help / color / mirror / Atom feed
* [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion
@ 2021-03-24 10:04 acoplan at gcc dot gnu.org
2021-03-24 10:06 ` [Bug target/99748] " acoplan at gcc dot gnu.org
` (6 more replies)
0 siblings, 7 replies; 8+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-03-24 10:04 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
Bug ID: 99748
Summary: MVE: Wrong code at -O0 with float to integer
conversion
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: target
Assignee: unassigned at gcc dot gnu.org
Reporter: acoplan at gcc dot gnu.org
Target Milestone: ---
GCC miscompiles the following testcase:
int main() {
float a = 1.0f;
return (int)a != 1;
}
with -march=armv8.1-m.main+mve -mfloat-abi=hard. The program should return 0
but returns 1 when compiled with these options. Looking at the generated code:
main:
@ args = 0, pretend = 0, frame = 8
@ frame_needed = 1, uses_anonymous_args = 0
push {r7, lr}
sub sp, sp, #8
add r7, sp, #0
mov r3, #1065353216
str r3, [r7, #4] @ float
vldr.32 s0, [r7, #4]
bl __aeabi_f2iz
mov r3, r0
cmp r3, #1
ite ne
movne r3, #1
moveq r3, #0
uxtb r3, r3
mov r0, r3
adds r7, r7, #8
mov sp, r7
@ sp needed
pop {r7, pc}
.size main, .-main
we use the aeabi_f2iz libcall to do the float to integer conversion, passing
the argument in the s0 (VFP) register. However, looking at the implementation
of aeabi_f2iz in libgcc/config/arm/ieee754-sf.S, the function appears to be
expecting its argument in the GPR r0. So we do the conversion on whatever
happens to be in r0 when the libcall is made.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
@ 2021-03-24 10:06 ` acoplan at gcc dot gnu.org
2021-03-24 10:15 ` acoplan at gcc dot gnu.org
` (5 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-03-24 10:06 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
--- Comment #1 from Alex Coplan <acoplan at gcc dot gnu.org> ---
I should have mentioned, I found this because a number of the execution tests
are failing when testing with --with-arch=armv8.1-m.main+mve --with-float=hard.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
2021-03-24 10:06 ` [Bug target/99748] " acoplan at gcc dot gnu.org
@ 2021-03-24 10:15 ` acoplan at gcc dot gnu.org
2021-03-31 14:35 ` acoplan at gcc dot gnu.org
` (4 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-03-24 10:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
--- Comment #2 from Alex Coplan <acoplan at gcc dot gnu.org> ---
GCC 10 also has the issue, so not a regression.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
2021-03-24 10:06 ` [Bug target/99748] " acoplan at gcc dot gnu.org
2021-03-24 10:15 ` acoplan at gcc dot gnu.org
@ 2021-03-31 14:35 ` acoplan at gcc dot gnu.org
2021-04-06 8:07 ` cvs-commit at gcc dot gnu.org
` (3 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-03-31 14:35 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
Alex Coplan <acoplan at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Ever confirmed|0 |1
Assignee|unassigned at gcc dot gnu.org |acoplan at gcc dot gnu.org
Last reconfirmed| |2021-03-31
Status|UNCONFIRMED |ASSIGNED
--- Comment #3 from Alex Coplan <acoplan at gcc dot gnu.org> ---
I'm taking a look.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
` (2 preceding siblings ...)
2021-03-31 14:35 ` acoplan at gcc dot gnu.org
@ 2021-04-06 8:07 ` cvs-commit at gcc dot gnu.org
2021-04-06 8:14 ` acoplan at gcc dot gnu.org
` (2 subsequent siblings)
6 siblings, 0 replies; 8+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2021-04-06 8:07 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
--- Comment #4 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Alex Coplan <acoplan@gcc.gnu.org>:
https://gcc.gnu.org/g:16ea7f57891d3fe885ee55b2917208695e184714
commit r11-7999-g16ea7f57891d3fe885ee55b2917208695e184714
Author: Alex Coplan <alex.coplan@arm.com>
Date: Tue Apr 6 09:06:27 2021 +0100
arm: Fix PCS for SFmode -> SImode libcalls [PR99748]
This patch fixes PR99748 which shows us trying to pass the argument to
__aeabi_f2iz in the VFP register s0 when the library function is
expecting to use the GPR r0. It also fixes the __aeabi_f2uiz case which
was broken in the same way.
For the testcase in the PR, here is the code we generate before the
patch (with -mfloat-abi=hard -march=armv8.1-m.main+mve -O0):
main:
push {r7, lr}
sub sp, sp, #8
add r7, sp, #0
mov r3, #1065353216
str r3, [r7, #4] @ float
vldr.32 s0, [r7, #4]
bl __aeabi_f2iz
mov r3, r0
cmp r3, #1
[...]
This becomes:
main:
push {r7, lr}
sub sp, sp, #8
add r7, sp, #0
mov r3, #1065353216
str r3, [r7, #4] @ float
ldr r0, [r7, #4] @ float
bl __aeabi_f2iz
mov r3, r0
cmp r3, #1
[...]
after the patch. We see a similar change for the same testcase with a
cast to unsigned instead of int.
gcc/ChangeLog:
PR target/99748
* config/arm/arm.c (arm_libcall_uses_aapcs_base): Also use base
PCS for [su]fix_optab.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
` (3 preceding siblings ...)
2021-04-06 8:07 ` cvs-commit at gcc dot gnu.org
@ 2021-04-06 8:14 ` acoplan at gcc dot gnu.org
2021-04-23 11:40 ` cvs-commit at gcc dot gnu.org
2021-04-23 11:41 ` acoplan at gcc dot gnu.org
6 siblings, 0 replies; 8+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-04-06 8:14 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
--- Comment #5 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Fixed on trunk so far, needs a backport to GCC 10.
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
` (4 preceding siblings ...)
2021-04-06 8:14 ` acoplan at gcc dot gnu.org
@ 2021-04-23 11:40 ` cvs-commit at gcc dot gnu.org
2021-04-23 11:41 ` acoplan at gcc dot gnu.org
6 siblings, 0 replies; 8+ messages in thread
From: cvs-commit at gcc dot gnu.org @ 2021-04-23 11:40 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
--- Comment #6 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Alex Coplan
<acoplan@gcc.gnu.org>:
https://gcc.gnu.org/g:283367662c25057fd7c9c98257cca858f85b75fc
commit r10-9755-g283367662c25057fd7c9c98257cca858f85b75fc
Author: Alex Coplan <alex.coplan@arm.com>
Date: Tue Apr 6 09:06:27 2021 +0100
arm: Fix PCS for SFmode -> SImode libcalls [PR99748]
This patch fixes PR99748 which shows us trying to pass the argument to
__aeabi_f2iz in the VFP register s0 when the library function is
expecting to use the GPR r0. It also fixes the __aeabi_f2uiz case which
was broken in the same way.
For the testcase in the PR, here is the code we generate before the
patch (with -mfloat-abi=hard -march=armv8.1-m.main+mve -O0):
main:
push {r7, lr}
sub sp, sp, #8
add r7, sp, #0
mov r3, #1065353216
str r3, [r7, #4] @ float
vldr.32 s0, [r7, #4]
bl __aeabi_f2iz
mov r3, r0
cmp r3, #1
[...]
This becomes:
main:
push {r7, lr}
sub sp, sp, #8
add r7, sp, #0
mov r3, #1065353216
str r3, [r7, #4] @ float
ldr r0, [r7, #4] @ float
bl __aeabi_f2iz
mov r3, r0
cmp r3, #1
[...]
after the patch. We see a similar change for the same testcase with a
cast to unsigned instead of int.
gcc/ChangeLog:
PR target/99748
* config/arm/arm.c (arm_libcall_uses_aapcs_base): Also use base
PCS for [su]fix_optab.
(cherry picked from commit 16ea7f57891d3fe885ee55b2917208695e184714)
^ permalink raw reply [flat|nested] 8+ messages in thread
* [Bug target/99748] MVE: Wrong code at -O0 with float to integer conversion
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
` (5 preceding siblings ...)
2021-04-23 11:40 ` cvs-commit at gcc dot gnu.org
@ 2021-04-23 11:41 ` acoplan at gcc dot gnu.org
6 siblings, 0 replies; 8+ messages in thread
From: acoplan at gcc dot gnu.org @ 2021-04-23 11:41 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99748
Alex Coplan <acoplan at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Resolution|--- |FIXED
Status|ASSIGNED |RESOLVED
--- Comment #7 from Alex Coplan <acoplan at gcc dot gnu.org> ---
Fixed for 10.4, so fixed everywhere.
^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-04-23 11:41 UTC | newest]
Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-03-24 10:04 [Bug target/99748] New: MVE: Wrong code at -O0 with float to integer conversion acoplan at gcc dot gnu.org
2021-03-24 10:06 ` [Bug target/99748] " acoplan at gcc dot gnu.org
2021-03-24 10:15 ` acoplan at gcc dot gnu.org
2021-03-31 14:35 ` acoplan at gcc dot gnu.org
2021-04-06 8:07 ` cvs-commit at gcc dot gnu.org
2021-04-06 8:14 ` acoplan at gcc dot gnu.org
2021-04-23 11:40 ` cvs-commit at gcc dot gnu.org
2021-04-23 11:41 ` acoplan at gcc dot gnu.org
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).