* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
@ 2024-06-18 7:20 ` sjames at gcc dot gnu.org
2024-06-18 7:22 ` sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-18 7:20 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #1 from Sam James <sjames at gcc dot gnu.org> ---
* Adding optimize("O2") or O0 to ReallocateWindowBuffer fixes it (it's a
realloc wrapper)
* We go wrong in analyzeResult and return a bogus result
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
2024-06-18 7:20 ` [Bug ipa/115533] " sjames at gcc dot gnu.org
@ 2024-06-18 7:22 ` sjames at gcc dot gnu.org
2024-06-18 7:24 ` sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-18 7:22 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #2 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58459
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58459&action=edit
replaygain_analysis-bad.c.o.xz
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
2024-06-18 7:20 ` [Bug ipa/115533] " sjames at gcc dot gnu.org
2024-06-18 7:22 ` sjames at gcc dot gnu.org
@ 2024-06-18 7:24 ` sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-18 7:24 UTC (permalink / raw)
To: gcc-bugs
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Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #58459|0 |1
is obsolete| |
--- Comment #3 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58460
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58460&action=edit
replaygain_analysis-bad.c.o.xz
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-18 7:25 UTC (permalink / raw)
To: gcc-bugs
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--- Comment #4 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58461
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58461&action=edit
replaygain_analysis-good.c.o.xz
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: rguenth at gcc dot gnu.org @ 2024-06-18 10:27 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |rguenth at gcc dot gnu.org
Version|unknown |15.0
Target Milestone|--- |12.4
--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
I wonder if it's the badly tested interaction between IPA opts and IPA PTA,
I assume -O2 -ftree-vectorize instead of -O3 isn't enough to reproduce?
I don't think that GCC 11 working means anything - IPA PTA doesn't get
much changes, so it's likely just now actually doing sth meaningful (bad)
with IPA PTA info.
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: rguenth at gcc dot gnu.org @ 2024-06-20 9:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Target Milestone|12.4 |12.5
--- Comment #6 from Richard Biener <rguenth at gcc dot gnu.org> ---
GCC 12.4 is being released, retargeting bugs to GCC 12.5.
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-20 15:33 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #7 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58471
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58471&action=edit
test.c
Attached a first cut of a reduction, I still have more to do though.
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
` (6 preceding siblings ...)
2024-06-20 15:33 ` sjames at gcc dot gnu.org
@ 2024-06-20 15:33 ` sjames at gcc dot gnu.org
2024-06-20 21:47 ` [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75 sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-20 15:33 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #8 from Sam James <sjames at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #5)
> I wonder if it's the badly tested interaction between IPA opts and IPA PTA,
> I assume -O2 -ftree-vectorize instead of -O3 isn't enough to reproduce?
>
It isn't, surprisingly. It was also really sensitive to vectorisation -- for a
while, novector on one loop was enough, but it stopped being after reduction.
We'll see..
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-20 21:47 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Keywords|needs-bisection |
Summary|[12/13/14/15 regression] |[12/13/14/15 regression]
|flac miscompiled with -O3 |flac miscompiled with -O3
|-march=znver2 -fipa-pta |-march=znver2 -fipa-pta
|-fno-vect-cost-model |-fno-vect-cost-model since
| |r12-3893-g6390c5047adb75
--- Comment #9 from Sam James <sjames at gcc dot gnu.org> ---
r12-3893-g6390c5047adb75
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
` (8 preceding siblings ...)
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@ 2024-06-21 16:50 ` sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-21 16:50 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #58471|0 |1
is obsolete| |
--- Comment #10 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58479
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58479&action=edit
test.c
Another checkpoint
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-21 16:54 UTC (permalink / raw)
To: gcc-bugs
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--- Comment #11 from Sam James <sjames at gcc dot gnu.org> ---
(In reply to Sam James from comment #10)
> Created attachment 58479 [details]
> test.c
>
> Another checkpoint
Ugh, lout became uninitialised. I'll try again.
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-21 17:03 UTC (permalink / raw)
To: gcc-bugs
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Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #58479|0 |1
is obsolete| |
--- Comment #12 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58480
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58480&action=edit
test.c
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-21 19:08 UTC (permalink / raw)
To: gcc-bugs
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Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #58480|0 |1
is obsolete| |
--- Comment #13 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58481
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58481&action=edit
test.c
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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From: sjames at gcc dot gnu.org @ 2024-06-21 19:10 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |pinskia at gcc dot gnu.org
--- Comment #14 from Sam James <sjames at gcc dot gnu.org> ---
(In reply to Sam James from comment #13)
> Created attachment 58481 [details]
> test.c
If I do:
```
- if(k == 715635309.750000)
+
+ if(k != 715635440.437500)
__builtin_abort();
```
it starts to fail with gcc-11 -O0, which makes me worried I'm misunderstanding
some FP issue here.
$ gcc-15 test.c -o test -O3 -march=znver2 -fno-vect-cost-model -fipa-pta -o
test && ./test
Aborted (core dumped)
pinskia, could you take a look? I don't think I can do much more without hints
at least
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
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From: sjames at gcc dot gnu.org @ 2024-06-21 20:16 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #58481|0 |1
is obsolete| |
--- Comment #15 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58484
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58484&action=edit
test.c
iains & pinskia helped, now using fabs(...) < e (error is large though because
of all the accumulated multiplication error terms..)
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
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@ 2024-06-21 20:51 ` pinskia at gcc dot gnu.org
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From: pinskia at gcc dot gnu.org @ 2024-06-21 20:51 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Ever confirmed|0 |1
Last reconfirmed| |2024-06-21
--- Comment #16 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
So I am not sure if the reduced testcase is an issue.
You get the "bad" value if you use -ffp-contract=off too or -O0.
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
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From: sjames at gcc dot gnu.org @ 2024-06-23 2:20 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Sam James <sjames at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Attachment #58484|0 |1
is obsolete| |
--- Comment #17 from Sam James <sjames at gcc dot gnu.org> ---
Created attachment 58492
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=58492&action=edit
test.c
This seems to be the best I can get out of it.
The original (upstream) code passes with -ffp-contract=off, so if this is
invalid, no feelings will be hurt.
I'm going to keep looking for other IPA miscompilations when I have spare
cycles.
This reduced testcase passes with gcc 11 with -O3 -march=znver2
-fno-vect-cost-model -fipa-pta -ffp-contract=fast, but fails with 12+ with the
same options. The relationship with the vectoriser here makes it hard to
understand (in addition to my inexperience with FP so far).
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
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From: rguenth at gcc dot gnu.org @ 2024-06-24 7:12 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #18 from Richard Biener <rguenth at gcc dot gnu.org> ---
With -fipa-pta we add
+t.c:28:24: optimized: loop with 5 iterations completely unrolled (header
execution count 43151276)
+t.c:30:16: optimized: loop turned into non-loop; it never loops
...
-t.c:28:24: optimized: loop with 4 iterations completely unrolled (header
execution count 107374186)
+t.c:36:11: optimized: basic block part vectorized using 32 byte vectors
+t.c:36:11: optimized: basic block part vectorized using 8 byte vectors
the testcase still breaks when adding -fdisable-tree-cunroll
-fno-tree-loop-vectorize, then the only change is
+t.c:36:11: optimized: basic block part vectorized using 16 byte vectors
+t.c:36:11: optimized: basic block part vectorized using 8 byte vectors
when failing we have
t.c:36:11: missed: can't determine dependence between *_65 and *ad_68
t.c:36:11: note: removing SLP instance operations starting from: *_65 = _66;
w/o IPA PTA we have
# PT = nonlocal escaped null
_65 = a.6_13 + _64;
# PT = nonlocal escaped
ad_68 = ad_205 + 4;
with IPA PTA
# PT = null { D.4063 D.4066 } (nonlocal, escaped, escaped heap)
_65 = a.6_13 + _64;
# PT = { D.4062 D.4065 } (nonlocal, escaped, escaped heap)
ad_68 = ad_205 + 4;
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
` (17 preceding siblings ...)
2024-06-24 7:12 ` rguenth at gcc dot gnu.org
@ 2024-06-24 12:06 ` rguenth at gcc dot gnu.org
2024-06-24 19:15 ` amonakov at gcc dot gnu.org
` (2 subsequent siblings)
21 siblings, 0 replies; 23+ messages in thread
From: rguenth at gcc dot gnu.org @ 2024-06-24 12:06 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |amonakov at gcc dot gnu.org
--- Comment #19 from Richard Biener <rguenth at gcc dot gnu.org> ---
Note I can't exactly see something wrong. -ffp-contract=fast triggers
BB vectorization in 'ac', placing __restrict on 'ae' like
void ac(float *ad, float * __restrict ae, size_t t, float *a, float *b, size_t
af,
uint32_t) {
...
no longer requires -fipa-pta to reproduce the issue. I _think_ this
__restrict is OK (allocation is unnecessarily obfuscated in the test).
Alex fixed -ffp-contract=on but =fast is still default it seems.
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
` (18 preceding siblings ...)
2024-06-24 12:06 ` rguenth at gcc dot gnu.org
@ 2024-06-24 19:15 ` amonakov at gcc dot gnu.org
2024-06-24 19:32 ` sjames at gcc dot gnu.org
2024-06-24 20:44 ` amonakov at gcc dot gnu.org
21 siblings, 0 replies; 23+ messages in thread
From: amonakov at gcc dot gnu.org @ 2024-06-24 19:15 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #20 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
Sam, can you provide more context? It seems there is no downstream bugreport?
How does the alleged miscompilation manifest?
Note that effects of interplay of fp-contract=fast and vectorization can be
pretty epic, like the completely wrong strong green tint of blur filter in
RawTherapee (see screenshot at
https://github.com/Beep6581/RawTherapee/issues/6384 which was minimized and
reported as our PR 106902).
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
` (19 preceding siblings ...)
2024-06-24 19:15 ` amonakov at gcc dot gnu.org
@ 2024-06-24 19:32 ` sjames at gcc dot gnu.org
2024-06-24 20:44 ` amonakov at gcc dot gnu.org
21 siblings, 0 replies; 23+ messages in thread
From: sjames at gcc dot gnu.org @ 2024-06-24 19:32 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #21 from Sam James <sjames at gcc dot gnu.org> ---
It fell out when building media-libs/flac's tests after I threw in -fipa-pta in
a test container for a single run where I check trunk for regressions.
Building flac itself, I can reproduce it with:
```
export CFLAGS="-O3 -ggdb3 -march=znver2 -fipa-pta -fno-vect-cost-model"
export CXXFLAGS="-O3 -ggdb3 -march=znver2 -fipa-pta -fno-vect-cost-model"
export LDFLAGS="-Wl,-O1"
cmake -B build-bad -DINSTALL_MANPAGES=OFF -DCMAKE_BUILD_TYPE=Debug
-DBUILD_SHARED_LIBS=ON
make -C build-bad
ctest --test-dir build-bad -R generate_streams
ctest --test-dir build-bad --tests-information -o -R replaygain
--output-on-failure
```
(*BUILD_TYPE and *SHARED_LIBS can be emitted if desired - was just there for
debugging while I went as wanted assertions, and you can just run make -C
build-bad and then make -C build-bad check).
It fails like:
```
[...]
replaygain.flac: 64.820000 1.000000 64.820000 1.000000
CPU info (x86-64):
CMOV ....... Y
MMX ........ Y
SSE ........ Y
SSE2 ....... Y
SSE3 ....... Y
SSSE3 ...... Y
SSE41 ...... Y
SSE42 ...... Y
AVX ........ Y
FMA ........ Y
AVX2 ....... Y
BMI2 ....... Y
AVX OS sup . Y
CPU info (x86-64):
CMOV ....... Y
MMX ........ Y
SSE ........ Y
SSE2 ....... Y
SSE3 ....... Y
SSSE3 ...... Y
SSE41 ...... Y
SSE42 ...... Y
AVX ........ Y
FMA ........ Y
AVX2 ....... Y
BMI2 ....... Y
AVX OS sup . Y
ERROR, Expected -12.73 db instead of comment[1]: REPLAYGAIN_TRACK_GAIN=+64.82
dB
0% tests passed, 1 tests failed out of 1
Total Test time (real) = 0.09 sec
The following tests FAILED:
7 - replaygain (Failed)
Errors while running CTest
```
(Will check out your link now, thanks!)
^ permalink raw reply [flat|nested] 23+ messages in thread
* [Bug ipa/115533] [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model since r12-3893-g6390c5047adb75
2024-06-18 7:19 [Bug ipa/115533] New: [12/13/14/15 regression] flac miscompiled with -O3 -march=znver2 -fipa-pta -fno-vect-cost-model sjames at gcc dot gnu.org
` (20 preceding siblings ...)
2024-06-24 19:32 ` sjames at gcc dot gnu.org
@ 2024-06-24 20:44 ` amonakov at gcc dot gnu.org
21 siblings, 0 replies; 23+ messages in thread
From: amonakov at gcc dot gnu.org @ 2024-06-24 20:44 UTC (permalink / raw)
To: gcc-bugs
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115533
--- Comment #22 from Alexander Monakov <amonakov at gcc dot gnu.org> ---
Similar to the RawTherapee issue, SLP opportunities are created by predcom, so
either -fno-predictive-commoning or -fno-tree-slp-vectorize avoids numerical
runaway on the small testcase.
^ permalink raw reply [flat|nested] 23+ messages in thread