[Bug target/113615] New: internal compiler error: in extract_insn, at recog.cc:2812

[Bug target/113615] New: internal compiler error: in extract_insn, at recog.cc:2812

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

            Bug ID: 113615
           Summary: internal compiler error: in extract_insn, at
                    recog.cc:2812
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rguenth at gcc dot gnu.org
  Target Milestone: ---

I'm seeing a lot of ICEs like this when running libgomp testsuite with
offloading for gfx1030.

/space/rguenther/src/gcc-autopar_devel/libgomp/testsuite/libgomp.fortran/examples-4/declare_target-4.f90:
In function 'accum_._omp_fn.1':^M
/space/rguenther/src/gcc-autopar_devel/libgomp/testsuite/libgomp.fortran/examples-4/declare_target-4.f90:20:38:
error: unrecognizable insn:^M
(insn 108 107 109 6 (set (reg:V8SF 849)^M
        (unspec:V8SF [^M
                (reg:V8SF 844 [ vect__43.12_106 ]) repeated x2^M
                (const_int 1 [0x1])^M
            ] UNSPEC_PLUS_DPP_SHR))
"/space/rguenther/src/gcc-autopar_devel/libgomp/testsuite/libgomp.fortran/examples-4/declare_target-4.f90":22:29
discrim 1 -1^M  
     (nil))^M
during RTL pass: vregs^M
/space/rguenther/src/gcc-autopar_devel/libgomp/testsuite/libgomp.fortran/examples-4/declare_target-4.f90:20:38:
internal compiler error: in extract_insn, at recog.cc:2812^M

other ones:

(insn 93 92 94 7 (set (reg:V64DF 805)^M
        (unspec:V64DF [^M
                (reg:V64DF 802 [ vect__31.53_89 ])^M
                (const_int 1 [0x1])^M
            ] UNSPEC_MOV_DPP_SHR))
"/space/rguenther/src/gcc-autopar_devel/libgomp/testsuite/libgomp.fortran/examples-4/target_data-3.f90":51:41
-1^M

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

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

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

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
*** Bug 113645 has been marked as a duplicate of this bug. ***

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

Tobias Burnus <burnus at gcc dot gnu.org> changed:

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

--- Comment #2 from Tobias Burnus <burnus at gcc dot gnu.org> ---
> I'm seeing a lot of ICEs like this when running libgomp testsuite with
> offloading for gfx1030.

I wonder why Andrew S didn't see them (unless he did?). However, I did get a
similar/the same ICE for the testcase in PR113645.

I have not checked whether anything below applies to the PR as well or not but
as Andrew P has marked it as duplicate ...

* * *

Regarding PR113645: While, I have no real idea about GCC backend handling, the
following SEEMS TO FIX THE ISSUE for the ICE of the testcase with -O3 and
gfx1030 and gfx1100, also known as

possible patch:

--- a/gcc/config/gcn/gcn-valu.md
+++ b/gcc/config/gcn/gcn-valu.md
@@ -4273,9 +4273,10 @@
 (define_expand "fold_left_plus_<mode>"
  [(match_operand:<SCALAR_MODE> 0 "register_operand")
   (match_operand:<SCALAR_MODE> 1 "gcn_alu_operand")
   (match_operand:V_FP 2 "gcn_alu_operand")]
-  "can_create_pseudo_p ()
+  "!TARGET_RDNA2_PLUS
+   && can_create_pseudo_p ()
    && (flag_openacc || flag_openmp
        || flag_associative_math)"
   {
     rtx dest = operands[0];

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[ams at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

--- Comment #3 from Andrew Stubbs <ams at gcc dot gnu.org> ---
I did see these, but I hadn't had time to chase them up.

The proposed patch is exactly the sort of solution I was expecting to find,
short term. Have you confirmed that it fixes all the cases?

A proper solution is to find out how to implement reductions with the RDNA ISA,
of course, but that's probably non-trivial (as in, I'm pretty sure it's more
than renaming a few mnemonics), and low-priority as GCC does a reasonably good 
job without them.

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[burnus at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

--- Comment #4 from Tobias Burnus <burnus at gcc dot gnu.org> ---
Patch:
  https://gcc.gnu.org/pipermail/gcc-patches/2024-January/644181.html

It fixes this issue but two other kind of issues I still see for gfx1100.

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

--- Comment #5 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Tobias Burnus <burnus@gcc.gnu.org>:

https://gcc.gnu.org/g:7cc2262ec9a410dc56d1c1c6b950c922e14f621d

commit r14-8493-g7cc2262ec9a410dc56d1c1c6b950c922e14f621d
Author: Tobias Burnus <tburnus@baylibre.com>
Date:   Mon Jan 29 13:51:25 2024 +0100

    gcn/gcn-valu.md: Disable fold_left_plus for TARGET_RDNA2_PLUS [PR113615]

    gcc/ChangeLog:

            PR target/113615
            * config/gcn/gcn-valu.md (fold_left_plus_<mode>): Only
            define for !TARGET_RDNA2_PLUS.

    Signed-off-by: Tobias Burnus <tburnus@baylibre.com>

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[doko at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

Matthias Klose <doko at gcc dot gnu.org> changed:

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

--- Comment #6 from Matthias Klose <doko at gcc dot gnu.org> ---
Created attachment 57290
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=57290&action=edit
preprocessed source

see with trunk 20240131 building a cross compiler targeting alpha-linux-gnu,
attaching the preprocessed source. this worked with trunk 20240129.

// ../../../../../src/libstdc++-v3/src/c++17/floating_to_chars.cc: In function
'std::to_chars_result std::__floating_to_chars_shortest(char*, char*, T,
chars_format) [with T = double]':
// ../../../../../src/libstdc++-v3/src/c++17/floating_to_chars.cc:1306:3:
error: unrecognizable insn:
//  1306 |   }
//       |   ^
// (insn 712 711 713 22 (set (reg:DI 686 [ highparttmp_857 ])
//         (truncate:DI (lshiftrt:TI (mult:TI (zero_extend:TI (subreg:DI
(reg:TI 223 [ _319 ]) 0))
//                     (subreg:DI (reg:TI 225 [ _321 ]) 0))
//                 (const_int 64 [0x40]))))
"../../../../../src/libstdc++-v3/src/c++17/ryu/d2s_intrinsics.h":254:27 -1
//      (nil))
// during RTL pass: vregs
// ../../../../../src/libstdc++-v3/src/c++17/floating_to_chars.cc:1306:3:
internal compiler error: in extract_insn, at recog.cc:2812
// 0x7b030c _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
//      ../../src/gcc/rtl-error.cc:108
// 0x7b0328 _fatal_insn_not_found(rtx_def const*, char const*, int, char
const*)
//      ../../src/gcc/rtl-error.cc:116
// 0x7aed6e extract_insn(rtx_insn*)
//      ../../src/gcc/recog.cc:2812
// 0xe44cd5 instantiate_virtual_regs_in_insn
//      ../../src/gcc/function.cc:1611
// 0xe44cd5 instantiate_virtual_regs
//      ../../src/gcc/function.cc:1994
// 0xe44cd5 execute
//      ../../src/gcc/function.cc:2041
// Please submit a full bug report, with preprocessed source (by using
-freport-bug).

[Bug target/113615] [14 Regression] internal compiler error: in extract_insn, at recog.cc:2812

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

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

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

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Matthias Klose from comment #6)
> Created attachment 57290 [details]
> preprocessed source
> 
> see with trunk 20240131 building a cross compiler targeting alpha-linux-gnu,
> attaching the preprocessed source. this worked with trunk 20240129.

How is this related to the gcn bug?

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[doko at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

Matthias Klose <doko at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|[14 Regression] internal    |internal compiler error: in
                   |compiler error: in          |extract_insn, at
                   |extract_insn, at            |recog.cc:2812
                   |recog.cc:2812               |

--- Comment #8 from Matthias Klose <doko at gcc dot gnu.org> ---
filed PR113720 for the alpha-linux-gnu ICE

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

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

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

--- Comment #9 from Richard Biener <rguenth at gcc dot gnu.org> ---
This seems fixed now.

[Bug target/113615] internal compiler error: in extract_insn, at recog.cc:2812

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113615

--- Comment #10 from GCC Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Thomas Schwinge <tschwinge@gcc.gnu.org>:

https://gcc.gnu.org/g:641b50bffc06123853a1421c0dd5a318c353fd85

commit r14-9068-g641b50bffc06123853a1421c0dd5a318c353fd85
Author: Thomas Schwinge <tschwinge@baylibre.com>
Date:   Fri Feb 16 13:04:00 2024 +0100

    GCN: Conditionalize 'define_expand "reduc_<fexpander>_scal_<mode>"' on
'!TARGET_RDNA2_PLUS' [PR113615]

    On top of commit c7ec7bd1c6590cf4eed267feab490288e0b8d691
    "amdgcn: add -march=gfx1030 EXPERIMENTAL" conditionalizing
    'define_expand "reduc_<reduc_op>_scal_<mode>"' on
    '!TARGET_RDNA2' (later: '!TARGET_RDNA2_PLUS'), we then did similar in
    commit 7cc2262ec9a410dc56d1c1c6b950c922e14f621d
    "gcn/gcn-valu.md: Disable fold_left_plus for TARGET_RDNA2_PLUS [PR113615]"
    to conditionalize 'define_expand "fold_left_plus_<mode>"' on
    '!TARGET_RDNA2_PLUS', but I found we also need to conditionalize the
related
    'define_expand "reduc_<fexpander>_scal_<mode>"' on '!TARGET_RDNA2_PLUS', to
    avoid ICEs like:

        [...]/gcc.dg/vect/pr108608.c: In function 'foo':
        [...]/gcc.dg/vect/pr108608.c:9:1: error: unrecognizable insn:
        (insn 34 33 35 2 (set (reg:V64DF 723)
                (unspec:V64DF [
                        (reg:V64DF 690 [ vect_m_11.20 ])
                        (const_int 1 [0x1])
                    ] UNSPEC_MOV_DPP_SHR)) -1
             (nil))
        during RTL pass: vregs

    Similar for 'gcc.dg/vect/vect-fmax-2.c', 'gcc.dg/vect/vect-fmin-2.c', and
    'UNSPEC_SMAX_DPP_SHR' for 'gcc.dg/vect/vect-fmax-1.c', and
    'UNSPEC_SMIN_DPP_SHR' for 'gcc.dg/vect/vect-fmin-1.c', when running
'vect.exp'
    for 'check-gcc-c'.

            PR target/113615
            gcc/
            * config/gcn/gcn-valu.md (define_expand
"reduc_<fexpander>_scal_<mode>"):
            Conditionalize on '!TARGET_RDNA2_PLUS'.
            * config/gcn/gcn.cc (gcn_expand_dpp_shr_insn)
            (gcn_expand_reduc_scalar):
            'gcc_checking_assert (!TARGET_RDNA2_PLUS);'.