[Bug target/94279] New: [amdgcn] internal compiler error: RTL check: expected code 'const_int', have 'reg' in rtx_to_poly_int64, at rtl.h:2379

[tschwinge at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94279

            Bug ID: 94279
           Summary: [amdgcn] internal compiler error: RTL check: expected
                    code 'const_int', have 'reg' in rtx_to_poly_int64, at
                    rtl.h:2379
           Product: gcc
           Version: unknown
            Status: UNCONFIRMED
          Keywords: openmp
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tschwinge at gcc dot gnu.org
                CC: ams at gcc dot gnu.org, jakub at gcc dot gnu.org, jules at 
gcc dot gnu.org
  Target Milestone: ---
            Target: amdgcn

This is with GCC commit b73f69020f08208d2d969fcf8879bd294a6e3596 sources, with
commit b12fb08bd95d7dbb9fd6af120ee0b4c658a3deb1, and commit
65858e1869be4a54f8e0e2073a4aa99b15471273 cherry-picked, and PR94248 fixed with
Jakub's 'reg_overlap_mentioned_p' patch.

Relative to a GCC nvptx offloading configuration, when adding amdgcn offloading
(with '--enable-checking=yes,extra,rtl'), I see the following regression:

    [-PASS:-]{+FAIL: libgomp.c/../libgomp.c-c++-common/for-5.c (internal
compiler error)+}
    {+FAIL:+} libgomp.c/../libgomp.c-c++-common/for-5.c (test for excess
errors)
    [-PASS:-]{+UNRESOLVED:+} libgomp.c/../libgomp.c-c++-common/for-5.c
[-execution test-]{+compilation failed to produce executable+}

    during RTL pass: split2
   
[...]/source-gcc/libgomp/testsuite/libgomp.c/../libgomp.c-c++-common/for-2.h:69:9:
internal compiler error: RTL check: expected code 'const_int', have 'reg' in
rtx_to_poly_int64, at rtl.h:2379
    0x54e115 ???
            [...]/source-gcc/gcc/rtl.c:881
    0xb0a5c4 ???
            [...]/source-gcc/gcc/rtl.h:2379
    0xabf9ad ???
            [...]/source-gcc/gcc/recog.c:2974
    0xabfb48 ???
            [...]/source-gcc/gcc/recog.c:4026
    [...]
    mkoffload: fatal error:
[...]/build-gcc/./gcc/x86_64-pc-linux-gnu-accel-amdgcn-amdhsa-gcc returned 1
exit status
    compilation terminated.
    [...]

Same for 'libgomp.c++' variant.

Supposedly same problem for:

    [-PASS:-]{+FAIL: libgomp.c/../libgomp.c-c++-common/pr66199-2.c (internal
compiler error)+}
    {+FAIL:+} libgomp.c/../libgomp.c-c++-common/pr66199-2.c (test for excess
errors)
    [-PASS:-]{+UNRESOLVED:+} libgomp.c/../libgomp.c-c++-common/pr66199-2.c
[-execution test-]{+compilation failed to produce executable+}

Same for 'libgomp.c++' variant.

    [-PASS:-]{+FAIL: libgomp.c/../libgomp.c-c++-common/pr66199-5.c (internal
compiler error)+}
    {+FAIL:+} libgomp.c/../libgomp.c-c++-common/pr66199-5.c (test for excess
errors)
    [-PASS:-]{+UNRESOLVED:+} libgomp.c/../libgomp.c-c++-common/pr66199-5.c
[-execution test-]{+compilation failed to produce executable+}

Same for 'libgomp.c++' variant.

    [-PASS:-]{+FAIL: libgomp.c/../libgomp.c-c++-common/pr66199-7.c (internal
compiler error)+}
    {+FAIL:+} libgomp.c/../libgomp.c-c++-common/pr66199-7.c (test for excess
errors)
    [-PASS:-]{+UNRESOLVED:+} libgomp.c/../libgomp.c-c++-common/pr66199-7.c
[-execution test-]{+compilation failed to produce executable+}

Same for 'libgomp.c++' variant.

    [-PASS:-]{+FAIL: libgomp.c/../libgomp.c-c++-common/pr66199-8.c (internal
compiler error)+}
    {+FAIL:+} libgomp.c/../libgomp.c-c++-common/pr66199-8.c (test for excess
errors)
    [-PASS:-]{+UNRESOLVED:+} libgomp.c/../libgomp.c-c++-common/pr66199-8.c
[-execution test-]{+compilation failed to produce executable+}

Same for 'libgomp.c++' variant.