[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #21 from Iain Sandoe --- Author: iains Date: Sun Sep 8 19:41:20 2019 New Revision: 275495 URL: https://gcc.gnu.org/viewcvs?rev=275495=gcc=rev Log: [X86, testsuite] Fix PR rtl-optimisation/64895 XPASSes. These tests had started to XPASS on pic targets where the codegen is now as expected. 2019-09-08 Iain Sandoe Backport from mainline. 2019-05-23 Iain Sandoe PR rtl-optimisation/64895 * gcc.target/i386/fuse-caller-save-rec.c: Remove XFAILs. * gcc.target/i386/fuse-caller-save.c: Likewise. * gcc.target/i386/fuse-caller-save-xmm.c: Adjust tests for PIC cases, remove XFAILs. Modified: branches/gcc-7-branch/gcc/testsuite/ChangeLog branches/gcc-7-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save-rec.c branches/gcc-7-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save-xmm.c branches/gcc-7-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #20 from Iain Sandoe --- Author: iains Date: Fri Aug 30 19:00:44 2019 New Revision: 275213 URL: https://gcc.gnu.org/viewcvs?rev=275213=gcc=rev Log: [Darwin, testsuite] Backport fix for 64895 XPASSes. These tests don't fail on Darwin. 2019-08-30 Iain Sandoe Backport from mainline. 2019-05-23 Iain Sandoe PR rtl-optimisation/64895 * gcc.target/i386/fuse-caller-save-rec.c: Remove XFAILs. * gcc.target/i386/fuse-caller-save.c: Likewise. * gcc.target/i386/fuse-caller-save-xmm.c: Adjust tests for PIC cases, remove XFAILs. Modified: branches/gcc-8-branch/gcc/testsuite/ChangeLog branches/gcc-8-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save-rec.c branches/gcc-8-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save-xmm.c branches/gcc-8-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #19 from Iain Sandoe --- testsuite fix applied for pic targets on trunk and 9.2
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #18 from Iain Sandoe --- Author: iains Date: Sun Aug 4 10:24:34 2019 New Revision: 274062 URL: https://gcc.gnu.org/viewcvs?rev=274062=gcc=rev Log: Darwin, X86, backport fixes for 64895. Although this is marked as rtl-optimisation, the Darwin issue is that the testcase XPASS there since the codegen is different. 2019-08-04 Iain Sandoe Backport from mainline. 2019-05-23 Iain Sandoe PR rtl-optimisation/64895 * gcc.target/i386/fuse-caller-save-rec.c: Remove XFAILs. * gcc.target/i386/fuse-caller-save.c: Likewise. * gcc.target/i386/fuse-caller-save-xmm.c: Adjust tests for PIC cases, remove XFAILs. Modified: branches/gcc-9-branch/gcc/testsuite/ChangeLog branches/gcc-9-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save-rec.c branches/gcc-9-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save-xmm.c branches/gcc-9-branch/gcc/testsuite/gcc.target/i386/fuse-caller-save.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #17 from Iain Sandoe --- Author: iains Date: Thu May 23 09:23:47 2019 New Revision: 271544 URL: https://gcc.gnu.org/viewcvs?rev=271544=gcc=rev Log: x86, testsuite - update fuse-caller-save tests. These tests had started to XPASS on pic targets where the codegen is now as expected. gcc/testsuite/ 2019-05-23 Iain Sandoe PR rtl-optimisation/64895 * gcc.target/i386/fuse-caller-save-rec.c: Remove XFAILs. * gcc.target/i386/fuse-caller-save.c: Likewise. * gcc.target/i386/fuse-caller-save-xmm.c: Adjust tests for PIC cases, remove XFAILs. Modified: trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gcc.target/i386/fuse-caller-save-rec.c trunk/gcc/testsuite/gcc.target/i386/fuse-caller-save-xmm.c trunk/gcc/testsuite/gcc.target/i386/fuse-caller-save.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #16 from Iain Sandoe --- Created attachment 46398 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=46398=edit testsuite patch Will post this later, tested on x86_64-linux and x86_64-darwin.
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895
Iain Sandoe changed:
What|Removed |Added
CC||iains at gcc dot gnu.org
--- Comment #15 from Iain Sandoe ---
(IIUC the thread here) It looks to me that the codegen is now DTRT for both pic
and non pic.
Darwin is doing pic by default, so sees XPASSes
There is no Linux pic test (so the change was not noticed there):
(I will produce a patch for the tests on the basis that this is now fixed).
Linux x86-64 (r271505):
Running target unix/-fpic/-m32
Using /usr/share/dejagnu/baseboards/unix.exp as board description file for
target.
Using /usr/share/dejagnu/config/unix.exp as generic interface file for target.
Using /home/iains/gcc-trunk/src-local/gcc/testsuite/config/default.exp as
tool-and-target-specific interface file.
Running /home/iains/gcc-trunk/src-local/gcc/testsuite/gcc.target/i386/i386.exp
...
XPASS: gcc.target/i386/fuse-caller-save-rec.c scan-assembler-not push
XPASS: gcc.target/i386/fuse-caller-save-rec.c scan-assembler-not pop
XPASS: gcc.target/i386/fuse-caller-save-rec.c scan-assembler-times
addl\t%[re]?dx, %[re]?ax 1
FAIL: gcc.target/i386/fuse-caller-save-xmm.c scan-assembler-times
addpd\t\\.?LC0.*, %xmm0 1
XPASS: gcc.target/i386/fuse-caller-save-xmm.c scan-assembler-times
addpd\t%xmm1, %xmm0 1
XPASS: gcc.target/i386/fuse-caller-save.c scan-assembler-not push
XPASS: gcc.target/i386/fuse-caller-save.c scan-assembler-not pop
XPASS: gcc.target/i386/fuse-caller-save.c scan-assembler-times
addl\t%[re]?d[ix], %[re]?ax 1
=== gcc Summary for unix/-fpic/-m64 ===
# of expected passes18
=
code output below - Darwin produces the same (or equivalent, for m32/pic).
=
(extraneous lines snipped for clarity)
fuse-caller-save-rec.c -O2 -fipa-ra -fomit-frame-pointer
-fno-optimize-sibling-calls -mregparm=1 -m32 -S {,-fpic}
bar:
cmpl$4, %eax
jg .L9
xorl%eax, %eax
ret
.L9:
subl$12, %esp
subl$3, %eax
callbar
addl$12, %esp
ret
foo:
subl$12, %esp
movl%eax, %edx
callbar
addl$12, %esp
addl%edx, %eax
ret
=
fuse-caller-save.c -O2 -fipa-ra -fomit-frame-pointer -mregparm=1 -m32 -S
{,-fpic}
bar:
addl$3, %eax
ret
foo:
movl%eax, %edx
callbar
addl%edx, %eax
ret
=
fuse-caller-save-xmm.c -O2 -fipa-ra -fomit-frame-pointer -msse2 -mno-avx -m32
-S
bar:
addpd .LC0, %xmm0
ret
foo:
subl$12, %esp
movapd %xmm0, %xmm1
callbar
addl$12, %esp
addpd %xmm1, %xmm0
ret
fuse-caller-save-xmm.c -O2 -fipa-ra -fomit-frame-pointer -msse2 -mno-avx -m32
-S -fpic
bar:
call__x86.get_pc_thunk.ax
addl$_GLOBAL_OFFSET_TABLE_, %eax
movapd .LC0@GOTOFF(%eax), %xmm1
addpd %xmm1, %xmm0
ret
foo:
subl$12, %esp
movapd %xmm0, %xmm2
callbar
addl$12, %esp
addpd %xmm2, %xmm0
ret
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #14 from Dominique d'Humieres --- > Between revisions r244915 and r244957 I got the following XPASS I have forgotten to say that it is on x86_64-apple-darwin16.
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #13 from Dominique d'Humieres --- Between revisions r244915 and r244957 I got the following XPASS XPASS: gcc.target/i386/fuse-caller-save-rec.c scan-assembler-not pop XPASS: gcc.target/i386/fuse-caller-save-rec.c scan-assembler-not push XPASS: gcc.target/i386/fuse-caller-save-rec.c scan-assembler-times addl\\t%[re]?dx, %[re]?ax 1 XPASS: gcc.target/i386/fuse-caller-save.c scan-assembler-not pop XPASS: gcc.target/i386/fuse-caller-save.c scan-assembler-not push XPASS: gcc.target/i386/fuse-caller-save.c scan-assembler-times addl\\t%[re]?d[ix], %[re]?ax 1
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895
Renlin Li changed:
What|Removed |Added
CC||renlin at gcc dot gnu.org
--- Comment #12 from Renlin Li ---
The same happens for aarch64.
> [hjl@gnu-tools-1 gcc]$ cat /tmp/x.c
> static int __attribute__((noinline))
> bar (int x)
> {
> if (x > 4)
> return bar (x - 3);
> return 0;
> }
>
> int __attribute__((noinline))
> foo (int y)
> {
> return y + bar (y);
> }
>
There is another problem here actually.
In this particular case, bar() is a static function which is not exported.
Although -fpic option is provided, pic_offset_table_rtx is not used at all in
function foo().
In this case, pic_offset_table_rtx may not be initialized at all. The target
hook TARGET_INIT_PIC_REG can be improved to initialize pic register only when
necessary.
On the other hand, if pic_offset_table_rtx is not used at all,
lra_risky_transformations_p should not be true. Does it make sensible?
diff --git a/gcc/lra-constraints.c b/gcc/lra-constraints.c
index a78edd8..d4a950f 100644
--- a/gcc/lra-constraints.c
+++ b/gcc/lra-constraints.c
@@ -4221,7 +4221,8 @@ lra_constraints (bool first_p)
lra_constraint_iter);
changed_p = false;
if (pic_offset_table_rtx
- && REGNO (pic_offset_table_rtx) >= FIRST_PSEUDO_REGISTER)
+ && (i = REGNO (pic_offset_table_rtx)) >= FIRST_PSEUDO_REGISTER
+ && lra_reg_info[i].nrefs > 0)
lra_risky_transformations_p = true;
else
lra_risky_transformations_p = false;
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #10 from vries at gcc dot gnu.org --- Author: vries Date: Mon Mar 16 09:42:21 2015 New Revision: 221448 URL: https://gcc.gnu.org/viewcvs?rev=221448root=gccview=rev Log: Revert 'Use actual_call_used_reg_set to find conflicting regs' 2015-03-16 Tom de Vries t...@codesourcery.com PR middle-end/65414 Revert: 2015-03-12 Tom de Vries t...@codesourcery.com PR rtl-optimization/64895 * lra-lives.c (check_pseudos_live_through_calls): Use actual_call_used_reg_set instead of call_used_reg_set, if available. Modified: trunk/gcc/ChangeLog trunk/gcc/lra-lives.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 Jakub Jelinek jakub at gcc dot gnu.org changed: What|Removed |Added Status|RESOLVED|REOPENED Resolution|FIXED |--- --- Comment #11 from Jakub Jelinek jakub at gcc dot gnu.org --- Patch has been reverted.
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 vries at gcc dot gnu.org changed: What|Removed |Added Status|NEW |RESOLVED Resolution|--- |FIXED Assignee|unassigned at gcc dot gnu.org |vries at gcc dot gnu.org --- Comment #8 from vries at gcc dot gnu.org --- Author: vries Date: Thu Mar 12 06:59:34 2015 New Revision: 221372 URL: https://gcc.gnu.org/viewcvs?rev=221372root=gccview=rev Log: Use actual_call_used_reg_set to find conflicting regs 2015-03-12 Tom de Vries t...@codesourcery.com * lra-lives.c (check_pseudos_live_through_calls): Use actual_call_used_reg_set instead of call_used_reg_set, if available. Modified: trunk/gcc/ChangeLog trunk/gcc/lra-lives.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #9 from vries at gcc dot gnu.org --- Author: vries Date: Thu Mar 12 08:01:24 2015 New Revision: 221374 URL: https://gcc.gnu.org/viewcvs?rev=221374root=gccview=rev Log: Revert 'require nonpic target' for fuse-caller-save*.c 2015-03-12 Tom de Vries t...@codesourcery.com PR rtl-optimization/64895 * gcc.target/i386/fuse-caller-save-rec.c: Revert require nonpic target. * gcc.target/i386/fuse-caller-save-xmm.c: Ditto. * gcc.target/i386/fuse-caller-save.c: Ditto. Modified: trunk/gcc/testsuite/ChangeLog trunk/gcc/testsuite/gcc.target/i386/fuse-caller-save-rec.c trunk/gcc/testsuite/gcc.target/i386/fuse-caller-save-xmm.c trunk/gcc/testsuite/gcc.target/i386/fuse-caller-save.c
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 --- Comment #6 from vries at gcc dot gnu.org --- From PR64342 comment 7: Register allocation seems to progress similarly, up until this message in reload, which seems to be directly related to the r216154 patch: ... Spill r86 after risky transformations Reassigning non-reload pseudos Assign 3 to r86 (freq=3000) ... I've looked a bit in more detail at this message. fipa-ra manages to allocate hardreg 1 (dx) to the call-crossing liverange as before. But setup_live_pseudos_and_spill_after_risky_transforms looks at the conflict regs, and finds that lra_reg_info[regno].conflict_hard_regs contains dx. Hence, it spills the liverange into an available reg, which happens to be hardreg 3 (bx). So, the risky transformations and fipa-ra have in common that they allocate registers from the conflict_hard_regs set. In the case of -fipa-ra, we don't want setup_live_pseudos_and_spill_after_risky_transforms to undo the -fipa-ra allocation, but currently there's no way to distinguish between the two. Using this patch, we make sure the conflict registers don't include dx for this testcase, and the test-cases passes again: ... diff --git a/gcc/lra-lives.c b/gcc/lra-lives.c index 9dfffb6..0231057 100644 --- a/gcc/lra-lives.c +++ b/gcc/lra-lives.c @@ -636,8 +636,11 @@ check_pseudos_live_through_calls (int regno) if (! sparseset_bit_p (pseudos_live_through_calls, regno)) return; sparseset_clear_bit (pseudos_live_through_calls, regno); + IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs, - call_used_reg_set); + !hard_reg_set_empty_p (lra_reg_info[regno].actual_call_used_reg_set) + ? lra_reg_info[regno].actual_call_used_reg_set + : call_used_reg_set); for (hr = 0; hr FIRST_PSEUDO_REGISTER; hr++) if (HARD_REGNO_CALL_PART_CLOBBERED (hr, PSEUDO_REGNO_MODE (regno))) ...
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 Vladimir Makarov vmakarov at gcc dot gnu.org changed: What|Removed |Added CC||vmakarov at gcc dot gnu.org --- Comment #7 from Vladimir Makarov vmakarov at gcc dot gnu.org --- (In reply to vries from comment #6) From PR64342 comment 7: Register allocation seems to progress similarly, up until this message in reload, which seems to be directly related to the r216154 patch: ... Spill r86 after risky transformations Reassigning non-reload pseudos Assign 3 to r86 (freq=3000) ... I've looked a bit in more detail at this message. fipa-ra manages to allocate hardreg 1 (dx) to the call-crossing liverange as before. But setup_live_pseudos_and_spill_after_risky_transforms looks at the conflict regs, and finds that lra_reg_info[regno].conflict_hard_regs contains dx. Hence, it spills the liverange into an available reg, which happens to be hardreg 3 (bx). So, the risky transformations and fipa-ra have in common that they allocate registers from the conflict_hard_regs set. In the case of -fipa-ra, we don't want setup_live_pseudos_and_spill_after_risky_transforms to undo the -fipa-ra allocation, but currently there's no way to distinguish between the two. Right. Introduction of pic pseudo and possible rematerializations of memory references with the pic pseudo made checking the new conflict first necessary. Before this it was not a problem as pic hard reg was used only for pic addressing. Using this patch, we make sure the conflict registers don't include dx for this testcase, and the test-cases passes again: ... diff --git a/gcc/lra-lives.c b/gcc/lra-lives.c index 9dfffb6..0231057 100644 --- a/gcc/lra-lives.c +++ b/gcc/lra-lives.c @@ -636,8 +636,11 @@ check_pseudos_live_through_calls (int regno) if (! sparseset_bit_p (pseudos_live_through_calls, regno)) return; sparseset_clear_bit (pseudos_live_through_calls, regno); + IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs, - call_used_reg_set); + !hard_reg_set_empty_p (lra_reg_info[regno].actual_call_used_reg_set) + ? lra_reg_info[regno].actual_call_used_reg_set + : call_used_reg_set); for (hr = 0; hr FIRST_PSEUDO_REGISTER; hr++) if (HARD_REGNO_CALL_PART_CLOBBERED (hr, PSEUDO_REGNO_MODE (regno))) ... The patch looks ok to me. Tom, could you prepare the patch (check it mostly for x86-64 bootstrap and testsuite) and commit it to the trunk. I approve it.
[Bug rtl-optimization/64895] RA picks the wrong register for -fipa-ra
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64895 Uroš Bizjak ubizjak at gmail dot com changed: What|Removed |Added Status|UNCONFIRMED |NEW Last reconfirmed||2015-03-06 CC||law at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #5 from Uroš Bizjak ubizjak at gmail dot com --- Confirmed, still happens with r221230 even after PR64342 fix: The testcase from the Comment #0, compiled with: -m32 -fpic -O2 -fipa-ra -fomit-frame-pointer -fno-optimize-sibling-calls -mregparm=1 -fno-asynchronous-unwind-tables: compiles to: foo: pushl %ebx movl%eax, %ebx subl$8, %esp callbar addl$8, %esp addl%ebx, %eax popl%ebx ret
