[Bug c/106751] New: internal compiler error: in purge_dead_edges, at cfgrtl.cc:3347

[Bug c/106751] New: internal compiler error: in purge_dead_edges, at cfgrtl.cc:3347

[christophe.leroy at csgroup dot eu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

            Bug ID: 106751
           Summary: internal compiler error: in purge_dead_edges, at
                    cfgrtl.cc:3347
           Product: gcc
           Version: 11.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: christophe.leroy at csgroup dot eu
  Target Milestone: ---

powerpc64-linux-gcc: warning: '-pipe' ignored because '-save-temps' specified
Using built-in specs.
COLLECT_AS_OPTIONS='-maltivec' '-mpower4' '-many'
COLLECT_GCC=/opt/gcc-12.2.0-nolibc/powerpc64-linux/bin/powerpc64-linux-gcc
Target: powerpc64-linux
Configured with: /home/arnd/git/gcc/configure --target=powerpc64-linux
--enable-targets=all
--prefix=/home/arnd/cross/x86_64/gcc-12.2.0-nolibc/powerpc64-linux
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Thread model: single
Supported LTO compression algorithms: zlib
gcc version 12.2.0 (GCC) 
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./arch/powerpc/include/generated/uapi -I ./include/uapi -I
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/opt/gcc-12.2.0-nolibc/powerpc64-linux/bin/../lib/gcc/powerpc64-linux/12.2.0/
-D __KERNEL__ -D HAVE_AS_ATHIGH=1 -D
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#include "..." search starts here:
#include <...> search starts here:
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 ./arch/powerpc/include/generated
 ./include
 ./arch/powerpc/include/uapi
 ./arch/powerpc/include/generated/uapi
 ./include/uapi
 ./include/generated/uapi
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End of search list.
COLLECT_GCC_OPTIONS='-nostdinc' '-I' './arch/powerpc/include' '-I'
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/opt/gcc-12.2.0-nolibc/powerpc64-linux/bin/../libexec/gcc/powerpc64-linux/12.2.0/cc1
-fpreprocessed kernel/locking/rtmutex_api.i -quiet -dumpdir kernel/locking/
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-fno-stack-clash-protection -fno-strict-overflow -fstack-check=no
-fconserve-stack -o kernel/locking/rtmutex_api.s
GNU C11 (GCC) version 12.2.0 (powerpc64-linux)
        compiled by GNU C version 8.3.0, GMP version 6.1.0, MPFR version 3.1.6,
MPC version 1.0.3, isl version isl-0.18-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
GNU C11 (GCC) version 12.2.0 (powerpc64-linux)
        compiled by GNU C version 8.3.0, GMP version 6.1.0, MPFR version 3.1.6,
MPC version 1.0.3, isl version isl-0.18-GMP

GGC heuristics: --param ggc-min-expand=100 --param ggc-min-heapsize=131072
Compiler executable checksum: 85577641c47121e3caf5e8a8694ad06b
during RTL pass: combine
In file included from kernel/locking/rtmutex_api.c:9:
kernel/locking/rtmutex.c: In function '__rt_mutex_slowlock.constprop':
kernel/locking/rtmutex.c:1612:1: internal compiler error: in purge_dead_edges,
at cfgrtl.cc:3347
 1612 | }
      | ^
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
See <https://gcc.gnu.org/bugs/> for instructions.

[Bug c/106751] internal compiler error: in purge_dead_edges, at cfgrtl.cc:3347

[christophe.leroy at csgroup dot eu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #1 from Christophe Leroy <christophe.leroy at csgroup dot eu> ---
Created attachment 53512
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=53512&action=edit
Preprocessed source

[Bug target/106751] internal compiler error: in purge_dead_edges, at cfgrtl.cc:3347

[christophe.leroy at csgroup dot eu]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #2 from Christophe Leroy <christophe.leroy at csgroup dot eu> ---
Same problem with at least gcc 11.3, 10.3, 9.5, 8.5 and 5.5

[Bug target/106751] internal compiler error: in purge_dead_edges, at cfgrtl.cc:3347

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #3 from Martin Liška <marxin at gcc dot gnu.org> ---
Reduced to:

$ cat rtmutex_api.i
struct task_struct *get_current();
struct task_struct {
  int __state;
} __attribute____rt_mutex_slowlock_locked() {
  asm goto("" : : : : __label_warn_on);
  __builtin_unreachable();
__label_warn_on:
  while (1)
    get_current()->__state = 0;
}

$ ppc64-linux-gnu-gcc rtmutex_api.i -c -O2
during RTL pass: combine
rtmutex_api.i: In function ‘__attribute____rt_mutex_slowlock_locked’:
rtmutex_api.i:10:1: internal compiler error: in purge_dead_edges, at
cfgrtl.cc:3347
   10 | }
      | ^
0x5e35b6 purge_dead_edges(basic_block_def*)
       
/home/marxin/BIG/buildbot/buildworker/marxinbox-gcc-trunk-ppc64/build/gcc/cfgrtl.cc:3347
0x773947 purge_all_dead_edges()
       
/home/marxin/BIG/buildbot/buildworker/marxinbox-gcc-trunk-ppc64/build/gcc/cfgrtl.cc:3368
0x13dc33f combine_instructions
       
/home/marxin/BIG/buildbot/buildworker/marxinbox-gcc-trunk-ppc64/build/gcc/combine.cc:1434
0x13dc33f rest_of_handle_combine
       
/home/marxin/BIG/buildbot/buildworker/marxinbox-gcc-trunk-ppc64/build/gcc/combine.cc:14978
0x13dc33f execute
       
/home/marxin/BIG/buildbot/buildworker/marxinbox-gcc-trunk-ppc64/build/gcc/combine.cc:15023
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

[Bug middle-end/106751] internal compiler error: in purge_dead_edges with inline-asm goto

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2022-08-26
            Summary|internal compiler error: in |internal compiler error: in
                   |purge_dead_edges, at        |purge_dead_edges with
                   |cfgrtl.cc:3347              |inline-asm goto
             Status|UNCONFIRMED                 |NEW
     Ever confirmed|0                           |1

[Bug middle-end/106751] internal compiler error: in purge_dead_edges with inline-asm goto

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
On x86_64 we get:

(jump_insn 5 2 8 2 (parallel [
            (asm_operands/v ("# %0") ("") 0 []
                 []
                 [
                    (label_ref:DI 8)
                ] /app/example.cpp:7)
            (clobber (reg:CC 17 flags))
        ]) "/app/example.cpp":7:3 -1
     (expr_list:REG_UNUSED (reg:CC 17 flags)
        (nil))
 -> 8)
(code_label 8 5 9 3 2 ("__label_warn_on") [1 uses])
(note 9 8 10 3 [bb 3] NOTE_INSN_BASIC_BLOCK)


But on PowerPC we get:

(jump_insn 5 2 12 2 (parallel [
            (asm_operands/v ("# %0") ("") 0 []
                 []
                 [
                    (label_ref:SI 8)
                ] /app/example.cpp:7)
            (clobber (reg:SI 98 ca))
        ]) "/app/example.cpp":7:3 -1
     (expr_list:REG_UNUSED (reg:SI 98 ca)
        (nil))
 -> 8)
(insn 12 5 8 2 (set (reg:SI 118)
        (const_int 0 [0])) "/app/example.cpp":11:28 545 {*movsi_internal1}
     (nil))
(code_label 8 12 9 3 2 ("__label_warn_on") [1 uses])

Notice the move before the the label, that is wrong.

[Bug rtl-optimization/106751] internal compiler error: in purge_dead_edges with inline-asm goto

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|powerpc64-linux             |powerpc64-linux,
                   |                            |aarch64-linux-gnu
          Component|middle-end                  |rtl-optimization

--- Comment #5 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
loop2_invariant moves the instruction.
You can also reproduce the failure on aarch64 with the following:
```
struct task_struct;
struct task_struct *get_current();
struct task_struct {
  int __state;
};
void f() {
  asm goto("# %0" : : : : __label_warn_on);
  __builtin_unreachable();
__label_warn_on:
  while (1)
    get_current()->__state = 1;
}
```
Which changes 0 for 1(on aarch64, zero can be used for a store which is why it
works for 0).
It works on x86_64 because the move accepts the 1.

Note on the trunk, the ICE is the following:
<source>: In function 'void f()':
<source>:12:1: error: in basic block 2:
   12 | }
      | ^
<source>:12:1: error: flow control insn inside a basic block
(jump_insn 5 2 12 2 (asm_operands/v ("# %0") ("") 0 []
         []
         [
            (label_ref:DI 8)
        ] <source>:7) "<source>":7:3 -1
     (nil)
 -> 8)
during RTL pass: loop2_invariant
dump file: /app/output.cpp.272r.loop2_invariant
<source>:12:1: internal compiler error: in rtl_verify_bb_insns, at
cfgrtl.cc:2797
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
See <https://gcc.gnu.org/bugs/> for instructions.
Compiler returned: 1

[Bug rtl-optimization/106751] internal compiler error: in purge_dead_edges with inline-asm goto

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Target|powerpc64-linux,            |powerpc64-linux,
                   |aarch64-linux-gnu           |aarch64-linux-gnu
                   |                            |arm-linux-gnu-eabi
      Known to fail|                            |4.5.4

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Fails all the way back to 4.5.4 with my reduced testcase on arm-linux-gnu-eabi
. I suspect it has always failed and if it passed with a larger testcase then
it was just a latent bug being exposed.

[Bug rtl-optimization/106751] internal compiler error: in purge_dead_edges with inline-asm goto

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

Segher Boessenkool <segher at gcc dot gnu.org> changed:

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

--- Comment #7 from Segher Boessenkool <segher at gcc dot gnu.org> ---
For me (powerpc64-linux) it fails with

===
106751.c:10:1: error: flow control insn inside a basic block
(jump_insn 6 3 13 2 (parallel [
            (asm_operands/v ("") ("") 0 []
                 []
                 [
                    (label_ref:DI 9)
                ] 106751.c:5)
            (clobber (reg:SI 98 ca))
        ]) "106751.c":5:3 -1
     (expr_list:REG_UNUSED (reg:SI 98 ca)
        (nil))
 -> 9)
during RTL pass: loop2_invariant
===

That pass did
===
Set in insn 13 is invariant (0), cost 4, depends on 
Decided to move invariant 0 -- gain 4
Invariant 0 moved without introducing a new temporary register
changing bb of uid 13
  from 3 to 2
===

It moved the insn after a jump_insn, not a good idea:

===
(jump_insn 6 3 13 2 (parallel [
            (asm_operands/v ("") ("") 0 []
                 []
                 [
                    (label_ref:DI 9)
                ] 106751.c:5)
            (clobber (reg:SI 98 ca))
        ]) "106751.c":5:3 -1
     (expr_list:REG_UNUSED (reg:SI 98 ca)
        (nil))
 -> 9)
(insn 13 6 9 2 (set (reg:SI 119)
        (const_int 0 [0])) "106751.c":9:28 562 {*movsi_internal1}
     (nil))
;;  succ:       3 [always]  count:10631108 (estimated locally)
===

Maybe it does not see this is an unconditional jump insn?

[Bug rtl-optimization/106751] [10/11/12/13 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|needs-bisection             |
           Priority|P3                          |P2
                 CC|                            |jakub at gcc dot gnu.org
            Summary|internal compiler error: in |[10/11/12/13 Regression]
                   |purge_dead_edges with       |internal compiler error: in
                   |inline-asm goto             |purge_dead_edges with
                   |                            |inline-asm goto
   Target Milestone|---                         |10.5

--- Comment #8 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Reduced testcase that ICEs on x86_64-linux too (-O2):
int *foo (void);

void
bar (void)
{
  asm goto ("" : : : : lab);
  __builtin_unreachable ();
lab:
  while (1)
    {
      int o;
      asm ("" : "=r" (o) : "g" (1));
      *foo () = o;
    }
}
Started with r0-128630-ga3afdbb80906a5553a64f9ba7686a57d2f43f536

[Bug rtl-optimization/106751] [10/11/12/13 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |hubicka at gcc dot gnu.org,
                   |                            |rguenth at gcc dot gnu.org

--- Comment #9 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
I'm afraid I don't know much about the RTL lim, but
1840          reorder_insns (inv->insn, inv->insn, BB_END (preheader));
with no check whether it is actually ok to append the statement at the end of
the preheader bb (at least no check that I can find) sounds wrong to me and I'm
just confused why it doesn't break stuff much more often.
From what I can see, loop-invariant.cc pass happens in between loop2_init and
loop2_done passes where the former calls loop_optimizer_init (LOOPS_NORMAL |
LOOPS_HAVE_RECORDED_EXITS);
which should ensure that loops have preheaders, but doesn't actually ask for
LOOPS_HAVE_FALLTHRU_PREHEADERS.
If the latter was on, then create_preheader would force splitting of the edge:
          /* If we want fallthru preheaders, also create forwarder block when
             preheader ends with a jump or has predecessors from loop.  */
          else if ((flags & CP_FALLTHRU_PREHEADERS)
                   && (JUMP_P (BB_END (single_entry->src))
                       || has_preds_from_loop (single_entry->src, loop)))
            need_forwarder_block = true;
So, should loop-invariant.cc split_edge the preheader edge if preheader block
ends with JUMP_P, or shall we somehow arrange for
LOOPS_HAVE_FALLTHRU_PREHEADERS?

[Bug rtl-optimization/106751] [10/11/12/13 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

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

--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 54103
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=54103&action=edit
gcc13-pr106751.patch

This seems to work on the testcase.

[Bug rtl-optimization/106751] [10/11/12/13 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #10)
> Created attachment 54103 [details]
> gcc13-pr106751.patch
> 
> This seems to work on the testcase.

looks reasonable.

[Bug rtl-optimization/106751] [10/11/12/13 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #12 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Jakub Jelinek <jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:ddcaa60983b50378bde1b7e327086fe0ce101795

commit r13-4739-gddcaa60983b50378bde1b7e327086fe0ce101795
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Dec 16 10:19:22 2022 +0100

    loop-invariant: Split preheader edge if the preheader bb ends with jump
[PR106751]

    The RTL loop passes only request simple preheaders, but don't require
    fallthru preheaders, while move_invariant_reg apparently assumes the
    latter, that it can just append instruction(s) to the end of the preheader
    basic block.

    The following patch fixes that by splitting the preheader edge if
    the preheader bb ends with a JUMP_INSN (asm goto in this case).
    Without that we get control flow in the middle of a bb.

    2022-12-16  Jakub Jelinek  <jakub@redhat.com>

            PR rtl-optimization/106751
            * loop-invariant.cc (move_invariant_reg): If preheader bb ends
            with a JUMP_INSN, split the preheader edge and emit invariants
            into the new preheader basic block.

            * gcc.c-torture/compile/pr106751.c: New test.

[Bug rtl-optimization/106751] [10/11/12 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11/12/13 Regression]    |[10/11/12 Regression]
                   |internal compiler error: in |internal compiler error: in
                   |purge_dead_edges with       |purge_dead_edges with
                   |inline-asm goto             |inline-asm goto

--- Comment #13 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed on the trunk so far.

[Bug rtl-optimization/106751] [10/11/12 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #14 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-12 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:4db6e1bf2f1647521dcd709bc3673f565fc327a5

commit r12-9128-g4db6e1bf2f1647521dcd709bc3673f565fc327a5
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Dec 16 10:19:22 2022 +0100

    loop-invariant: Split preheader edge if the preheader bb ends with jump
[PR106751]

    The RTL loop passes only request simple preheaders, but don't require
    fallthru preheaders, while move_invariant_reg apparently assumes the
    latter, that it can just append instruction(s) to the end of the preheader
    basic block.

    The following patch fixes that by splitting the preheader edge if
    the preheader bb ends with a JUMP_INSN (asm goto in this case).
    Without that we get control flow in the middle of a bb.

    2022-12-16  Jakub Jelinek  <jakub@redhat.com>

            PR rtl-optimization/106751
            * loop-invariant.cc (move_invariant_reg): If preheader bb ends
            with a JUMP_INSN, split the preheader edge and emit invariants
            into the new preheader basic block.

            * gcc.c-torture/compile/pr106751.c: New test.

    (cherry picked from commit ddcaa60983b50378bde1b7e327086fe0ce101795)

[Bug rtl-optimization/106751] [10/11 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11/12 Regression]       |[10/11 Regression] internal
                   |internal compiler error: in |compiler error: in
                   |purge_dead_edges with       |purge_dead_edges with
                   |inline-asm goto             |inline-asm goto

--- Comment #15 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed for gcc 12.3 too.

[Bug rtl-optimization/106751] [10/11 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #16 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-11 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:945edfa2d24e310bf3549a16f2ea4c881a9a138a

commit r11-10690-g945edfa2d24e310bf3549a16f2ea4c881a9a138a
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Dec 16 10:19:22 2022 +0100

    loop-invariant: Split preheader edge if the preheader bb ends with jump
[PR106751]

    The RTL loop passes only request simple preheaders, but don't require
    fallthru preheaders, while move_invariant_reg apparently assumes the
    latter, that it can just append instruction(s) to the end of the preheader
    basic block.

    The following patch fixes that by splitting the preheader edge if
    the preheader bb ends with a JUMP_INSN (asm goto in this case).
    Without that we get control flow in the middle of a bb.

    2022-12-16  Jakub Jelinek  <jakub@redhat.com>

            PR rtl-optimization/106751
            * loop-invariant.c (move_invariant_reg): If preheader bb ends
            with a JUMP_INSN, split the preheader edge and emit invariants
            into the new preheader basic block.

            * gcc.c-torture/compile/pr106751.c: New test.

    (cherry picked from commit ddcaa60983b50378bde1b7e327086fe0ce101795)

[Bug rtl-optimization/106751] [10 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[10/11 Regression] internal |[10 Regression] internal
                   |compiler error: in          |compiler error: in
                   |purge_dead_edges with       |purge_dead_edges with
                   |inline-asm goto             |inline-asm goto

--- Comment #17 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed for 11.4 as well.

[Bug rtl-optimization/106751] [10 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

--- Comment #18 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The releases/gcc-10 branch has been updated by Jakub Jelinek
<jakub@gcc.gnu.org>:

https://gcc.gnu.org/g:c88f917d2aa1c2ac065fbc0a10298f5551f392b6

commit r10-11348-gc88f917d2aa1c2ac065fbc0a10298f5551f392b6
Author: Jakub Jelinek <jakub@redhat.com>
Date:   Fri Dec 16 10:19:22 2022 +0100

    loop-invariant: Split preheader edge if the preheader bb ends with jump
[PR106751]

    The RTL loop passes only request simple preheaders, but don't require
    fallthru preheaders, while move_invariant_reg apparently assumes the
    latter, that it can just append instruction(s) to the end of the preheader
    basic block.

    The following patch fixes that by splitting the preheader edge if
    the preheader bb ends with a JUMP_INSN (asm goto in this case).
    Without that we get control flow in the middle of a bb.

    2022-12-16  Jakub Jelinek  <jakub@redhat.com>

            PR rtl-optimization/106751
            * loop-invariant.c (move_invariant_reg): If preheader bb ends
            with a JUMP_INSN, split the preheader edge and emit invariants
            into the new preheader basic block.

            * gcc.c-torture/compile/pr106751.c: New test.

    (cherry picked from commit ddcaa60983b50378bde1b7e327086fe0ce101795)

[Bug rtl-optimization/106751] [10 Regression] internal compiler error: in purge_dead_edges with inline-asm goto

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106751

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #19 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Fixed for 10.5 too.