[Bug target/98914] New: [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[Bug target/98914] New: [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

            Bug ID: 98914
           Summary: [11 Regression] ICE in rs6000_expand_vector_set, at
                    config/rs6000/rs6000.c:7198
           Product: gcc
           Version: 11.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---
            Target: powerpc-*-linux-gnu

gcc-11.0.0-alpha20210131 snapshot (g:98342bdd2b7085c9e7e4c9fbb07c3917a0013515)
ICEs when compiling the following testcase, reduced from
gcc/testsuite/gcc.target/powerpc/pr79251-run.p8.c, w/ -mvsx -Og:

void
foo (int __attribute__ ((altivec (vector__))) v)
{
  for (int k = 0; k < 1; ++k)
    v[k] = 0;
}

% powerpc-e300c3-linux-gnu-gcc-11.0.0 -mvsx -Og -c yo6irbnt.c
during RTL pass: expand
yo6irbnt.c: In function 'foo':
yo6irbnt.c:5:10: internal compiler error: in rs6000_expand_vector_set, at
config/rs6000/rs6000.c:7198
    5 |     v[k] = 0;
      |     ~~~~~^~~
0x731be0 rs6000_expand_vector_set(rtx_def*, rtx_def*, rtx_def*)
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/config/rs6000/rs6000.c:7198
0x157be60 ???
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/config/rs6000/vector.md:1251
0xceb038 maybe_expand_insn(insn_code, unsigned int, expand_operand*)
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/optabs.c:7820
0xb83bfd expand_vec_set_optab_fn
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/internal-fn.c:2871
0xb83bfd expand_VEC_SET
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/internal-fn.def:148
0x954357 expand_call_stmt
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/cfgexpand.c:2748
0x954357 expand_gimple_stmt_1
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/cfgexpand.c:3843
0x954357 expand_gimple_stmt
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/cfgexpand.c:4007
0x95a01a expand_gimple_basic_block
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/cfgexpand.c:6044
0x95bb5f execute
       
/var/tmp/portage/cross-powerpc-e300c3-linux-gnu/gcc-11.0.0_alpha20210131/work/gcc-11-20210131/gcc/cfgexpand.c:6728

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |11.0

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[luoxhu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

--- Comment #1 from luoxhu at gcc dot gnu.org ---
The type of k in the case should be "long" to reproduce the issue, 

ICE happens at 

rs6000_expand_vector_set:  gcc_assert (GET_MODE (idx) == E_SImode);


Reason is the vector index variable need be "signed int" for all vec_insert
prototype. 


ELFv2 ABI:
vector signed char vec_insert (signed char, vector signed char, signed int);
vector unsigned char vec_insert (unsigned char, vector unsigned char, signed
int);
vector signed int vec_insert (signed int, vector signed int, signed int);
vector unsigned int vec_insert (unsigned int, vector unsigned int, signed int);
vector signed long long vec_insert (signed long long, vector signed long long,
signed int);


Not sure all targets like X86/AArch64 also has some requirements, and whether
below fix reasonable to not generate IFN VEC_SET for stmt like 

VIEW_CONVERT_EXPR<unsigned char[16]>(v)[k_7] = 170;  ?


diff --git a/gcc/gimple-isel.cc b/gcc/gimple-isel.cc
index 2c78a08d3f1..dbbae270a36 100644
--- a/gcc/gimple-isel.cc
+++ b/gcc/gimple-isel.cc
@@ -77,6 +77,7 @@ gimple_expand_vec_set_expr (gimple_stmt_iterator *gsi)
       tree view_op0 = TREE_OPERAND (op0, 0);
       machine_mode outermode = TYPE_MODE (TREE_TYPE (view_op0));
       if (auto_var_in_fn_p (view_op0, cfun->decl)
+         && TYPE_MODE (TREE_TYPE (pos)) == E_SImode
          && !TREE_ADDRESSABLE (view_op0) && can_vec_set_var_idx_p (outermode))
        {
          location_t loc = gimple_location (stmt);

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

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

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

--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> ---
No, I think that's too restrictive.  ISTR we wanted to have "arbitrary" index
modes, if the target wants just SImode it can convert_move to it, no?

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Yeah.  The requirement that the index needs to be signed int is fine for the
intrinsics, but not otherwise.  And if it is an index into a vector with less
than 128 elements, one shouldn't care if the index is signed or unsigned char,
short, int or long long.

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[luoxhu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

--- Comment #4 from luoxhu at gcc dot gnu.org ---
*** Bug 98958 has been marked as a duplicate of this bug. ***

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

--- Comment #5 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Xiong Hu Luo <luoxhu@gcc.gnu.org>:

https://gcc.gnu.org/g:d0a5e8e1a84bdd6ce915c3be65da8af2552cd49e

commit r11-7755-gd0a5e8e1a84bdd6ce915c3be65da8af2552cd49e
Author: Xionghu Luo <luoxhu@linux.ibm.com>
Date:   Sun Mar 21 21:14:02 2021 -0500

    rs6000: Convert the vector set variable idx to DImode [PR98914]

    vec_insert defines the element argument type to be signed int by ELFv2
    ABI.  When expanding a vector with a variable rtx, convert the rtx type
    to DImode to support both intrinsic usage and other callers from
    rs6000_expand_vector_init produced by v[k] = val when k is long type.

    gcc/ChangeLog:

    2021-03-21  Xionghu Luo  <luoxhu@linux.ibm.com>

            PR target/98914
            * config/rs6000/rs6000.c (rs6000_expand_vector_set_var_p9):
            Convert idx to DImode.
            (rs6000_expand_vector_set_var_p8): Likewise.

    gcc/testsuite/ChangeLog:

    2021-03-21  Xionghu Luo  <luoxhu@linux.ibm.com>

            PR target/98914
            * gcc.target/powerpc/pr98914.c: New test.

[Bug target/98914] [11 Regression] ICE in rs6000_expand_vector_set, at config/rs6000/rs6000.c:7198

[luoxhu at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98914

luoxhu at gcc dot gnu.org changed:

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

--- Comment #6 from luoxhu at gcc dot gnu.org ---
Fixed on master.