[Bug target/112103] New: [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[Bug target/112103] New: [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[seurer at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

            Bug ID: 112103
           Summary: [14 regression] gcc.target/powerpc/rlwinm-0.c fails
                    after r14-4941-gd1bb9569d70304
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: seurer at gcc dot gnu.org
  Target Milestone: ---

g:d1bb9569d7030490fe7bb35af432f934560d689d, r14-4941-gd1bb9569d70304
make  -k check-gcc RUNTESTFLAGS="powerpc.exp=gcc.target/powerpc/rlwinm-0.c"
FAIL: gcc.target/powerpc/rlwinm-0.c scan-assembler-times (?n)^\\s+rldicl 3081
FAIL: gcc.target/powerpc/rlwinm-0.c scan-assembler-times (?n)^\\s+rlwinm 3093
# of expected passes            5
# of unexpected failures        2

These changes in code output are OK as neither the original rlwinm nor the
rldicl actually have any effect.  So in the short term the test case just needs
to update its instruction counts.  We are tracking something to get rid of the
extraneous ops later.

seurer@ltcden2-lp1:~/gcc/git/build/gcc-test$ diff rlwinm-0.s.r14-4940
rlwinm-0.s.r14-4941
5371c5371
<       rlwinm 3,3,0,0xffff
---
> 	rldicl 3,3,0,32
6089c6089
<       rlwinm 3,3,0,0xff
---
> 	rldicl 3,3,0,32
8959c8959
<       rlwinm 3,3,0,0xffff
---
> 	rldicl 3,3,0,32
9677c9677
<       rlwinm 3,3,0,0xff
---
> 	rldicl 3,3,0,32
12546c12546
<       rlwinm 3,3,0,0xffff
---
> 	rldicl 3,3,0,32
13264c13264
<       rlwinm 3,3,0,0xff
---
> 	rldicl 3,3,0,32
16131c16131
<       rlwinm 3,3,0,0xffff
---
> 	rldicl 3,3,0,32
19715c19715
<       rlwinm 3,3,0,0xffff
---
> 	rldicl 3,3,0,32
23298c23298
<       rlwinm 3,3,0,0xffff
---
> 	rldicl 3,3,0,32


commit d1bb9569d7030490fe7bb35af432f934560d689d (HEAD)
Author: Roger Sayle <roger@nextmovesoftware.com>
Date:   Thu Oct 26 10:06:59 2023 +0100

    PR 91865: Avoid ZERO_EXTEND of ZERO_EXTEND in make_compound_operation.

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[roger at nextmovesoftware dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Roger Sayle <roger at nextmovesoftware dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
             Status|UNCONFIRMED                 |NEW
                 CC|                            |roger at nextmovesoftware dot com
   Last reconfirmed|                            |2023-10-26

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

--- Comment #1 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Those are:

$ diff -up rlwinm-0.s{.12,}
--- rlwinm-0.s.12       2023-11-09 18:28:49.362639203 +0000
+++ rlwinm-0.s  2023-11-09 18:30:46.422896735 +0000
@@ -6747,7 +6747,7 @@ f_1_16_31:
 .LFB345:
        .cfi_startproc
        rlwinm 3,3,1,16,31
-       rlwinm 3,3,0,0xffff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -7645,7 +7645,7 @@ f_1_24_31:
 .LFB390:
        .cfi_startproc
        rlwinm 3,3,1,24,31
-       rlwinm 3,3,0,0xff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -11235,7 +11235,7 @@ f_2_16_31:
 .LFB570:
        .cfi_startproc
        rlwinm 3,3,2,16,31
-       rlwinm 3,3,0,0xffff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -12133,7 +12133,7 @@ f_2_24_31:
 .LFB615:
        .cfi_startproc
        rlwinm 3,3,2,24,31
-       rlwinm 3,3,0,0xff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -15722,7 +15722,7 @@ f_7_16_31:
 .LFB795:
        .cfi_startproc
        rlwinm 3,3,7,16,31
-       rlwinm 3,3,0,0xffff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -16620,7 +16620,7 @@ f_7_24_31:
 .LFB840:
        .cfi_startproc
        rlwinm 3,3,7,24,31
-       rlwinm 3,3,0,0xff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -20207,7 +20207,7 @@ f_8_16_31:
 .LFB1020:
        .cfi_startproc
        rlwinm 3,3,8,16,31
-       rlwinm 3,3,0,0xffff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -24691,7 +24691,7 @@ f_9_16_31:
 .LFB1245:
        .cfi_startproc
        rlwinm 3,3,9,16,31
-       rlwinm 3,3,0,0xffff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -29174,7 +29174,7 @@ f_15_16_31:
 .LFB1470:
        .cfi_startproc
        rlwinm 3,3,15,16,31
-       rlwinm 3,3,0,0xffff
+       rldicl 3,3,0,32
        blr
        .long 0
        .byte 0,0,0,0,0,0,0,0
@@ -67092,4 +67092,4 @@ f_31_31_31:
        .cfi_endproc
 .LFE3375:
        .size   f_31_31_31,.-.L.f_31_31_31
-       .ident  "GCC: (GNU) 12.0.1 20220406 (experimental)"
+       .ident  "GCC: (GNU) 14.0.0 20231103 (experimental)"

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

--- Comment #2 from Segher Boessenkool <segher at gcc dot gnu.org> ---
In all those cases the code is perfectly fine, but also in all of those cases
the
code is still suboptimal: the rldicl is just as superfluous as the second
rlwinm
was!  :-)

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

--- Comment #3 from Peter Bergner <bergner at gcc dot gnu.org> ---
(In reply to Segher Boessenkool from comment #2)
> In all those cases the code is perfectly fine, but also in all of those
> cases the
> code is still suboptimal: the rldicl is just as superfluous as the second
> rlwinm
> was!  :-)

So the superfluous second instruction is not really a regression, correct?  All
that changed with Roger's patch is we replaced a superfluous rlwinm with a
superfluous rldicl, correct?

...which is what caused the testcase to FAIL given it was looking for the old
mnemonic and found the new one.

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #4 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
So, let's just adjust the testcase then?

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

--- Comment #5 from Peter Bergner <bergner at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #4)
> So, let's just adjust the testcase then?

We still want to remove the superfluous instruction, but that should be covered
in a separate bug.  So yeah, I think this just needs a testsuite update.

Should we also drop the priority down too?  A P1 seems a little high for a
simple test case update.

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|unassigned at gcc dot gnu.org      |bergner at gcc dot gnu.org
             Status|NEW                         |ASSIGNED

--- Comment #6 from Peter Bergner <bergner at gcc dot gnu.org> ---
Testing the obvious patch on both LE and BE to ensure it works everywhere.

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                URL|                            |https://gcc.gnu.org/piperma
                   |                            |il/gcc-patches/2024-Februar
                   |                            |y/646008.html

--- Comment #7 from Peter Bergner <bergner at gcc dot gnu.org> ---
Testing was clean, so submitted.

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

--- Comment #8 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Peter Bergner <bergner@gcc.gnu.org>:

https://gcc.gnu.org/g:81e5f276c59897077ffe38202849c93e9c580c41

commit r14-9085-g81e5f276c59897077ffe38202849c93e9c580c41
Author: Peter Bergner <bergner@linux.ibm.com>
Date:   Tue Feb 20 13:44:43 2024 -0600

    rs6000: Update instruction counts due to combine changes [PR112103]

    The PR91865 combine fix changed instruction counts slightly for rlwinm-0.c.
    Adjust expected instruction counts accordingly.

    2024-02-20  Peter Bergner  <bergner@linux.ibm.com>

    gcc/testsuite/
            PR target/112103
            * gcc.target/powerpc/rlwinm-0.c: Adjust expected instruction
counts.

[Bug target/112103] [14 regression] gcc.target/powerpc/rlwinm-0.c fails after r14-4941-gd1bb9569d70304

[bergner at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112103

Peter Bergner <bergner at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://gcc.gnu.org/bugzill
                   |                            |a/show_bug.cgi?id=114004
         Resolution|---                         |FIXED
             Status|ASSIGNED                    |RESOLVED

--- Comment #9 from Peter Bergner <bergner at gcc dot gnu.org> ---
Fixed.


(In reply to Peter Bergner from comment #5)
> We still want to remove the superfluous instruction, but that should be
> covered in a separate bug.

The fixing of the superfluous insn is being tracked in PR114004.