[Bug tree-optimization/94683] New: ICE in forwprop when folding to a VEC_PERM_EXPR

[Bug tree-optimization/94683] New: ICE in forwprop when folding to a VEC_PERM_EXPR

[rsandifo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94683

            Bug ID: 94683
           Summary: ICE in forwprop when folding to a VEC_PERM_EXPR
           Product: gcc
           Version: 10.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: rsandifo at gcc dot gnu.org
  Target Milestone: ---

Compiling this with -march=armv8.2-a+sve -msve-vector-bits=256 -O3:

#include <arm_sve.h>

typedef float v8sf __attribute__((vector_size(32)));

svfloat32_t
f (svbool_t pg, svfloat32_t x, svfloat32_t y)
{
  v8sf a = svadd_x (pg, x, 1);
  v8sf b = { a[0], a[0], a[2], a[2], a[4], a[4], a[6], a[6] };
  return svdiv_x (pg, b, y);
}

gives:

foo.c: In function ‘f’:
foo.c:16:1: error: non-trivial conversion in ‘ssa_name’
   16 | }
      | ^
v8sf
__SVFloat32_t
b_17 = _16;
during GIMPLE pass: forwprop
dump file: foo.031t.forwprop1

[Bug tree-optimization/94683] ICE in forwprop when folding to a VEC_PERM_EXPR

[rsandifo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94683

rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2020-04-21
             Status|UNCONFIRMED                 |ASSIGNED
           Assignee|unassigned at gcc dot gnu.org      |rsandifo at gcc dot gnu.org

--- Comment #1 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> ---
Testing a patch.

[Bug tree-optimization/94683] ICE in forwprop when folding to a VEC_PERM_EXPR

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94683

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by Richard Sandiford <rsandifo@gcc.gnu.org>:

https://gcc.gnu.org/g:85353e24ca90282e1d3620682841f524de20475c

commit r10-7851-g85353e24ca90282e1d3620682841f524de20475c
Author: Richard Sandiford <richard.sandiford@arm.com>
Date:   Tue Apr 21 16:11:07 2020 +0100

    forwprop: Fix ICE when building a VEC_PERM_EXPR [PR94683]

    The type compatibility handling in simplify_vector_constructor is
    based on the number of elements and on element type compatibility,
    but that's no longer enough to ensure that two vector types are
    compatible.  This patch uses a VIEW_CONVERT_EXPR if the permutation
    type and result type are distinct.

    2020-04-21  Richard Sandiford  <richard.sandiford@arm.com>

    gcc/
            PR tree-optimization/94683
            * tree-ssa-forwprop.c (simplify_vector_constructor): Use a
            VIEW_CONVERT_EXPR to handle mixtures of similarly-structured
            but distinct vector types.

    gcc/testsuite/
            PR tree-optimization/94683
            * gcc.target/aarch64/sve/acle/general/pr94683.c: New test.

[Bug tree-optimization/94683] ICE in forwprop when folding to a VEC_PERM_EXPR

[rsandifo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94683

rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> changed:

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

--- Comment #3 from rsandifo at gcc dot gnu.org <rsandifo at gcc dot gnu.org> ---
Fixed on master.