https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92526
--- Comment #2 from rsandifo at gcc dot gnu.org
---
Author: rsandifo
Date: Thu Nov 21 17:45:36 2019
New Revision: 278592
URL: https://gcc.gnu.org/viewcvs?rev=278592=gcc=rev
Log:
Reject versioning for alignment with different masks (PR 92526)
Allowing mixed vector sizes broke the assumption in the following assert,
since it's now possible for different accesses to require different
levels of alignment:
/* FORNOW: use the same mask to test all potentially unaligned
references in the loop. The vectorizer currently supports
a single vector size, see the reference to
GET_MODE_NUNITS (TYPE_MODE (vectype)) where the
vectorization factor is computed. */
gcc_assert (!LOOP_VINFO_PTR_MASK (loop_vinfo)
|| LOOP_VINFO_PTR_MASK (loop_vinfo) == mask);
I guess we could try to over-align smaller accesses so that all
of them are consistent, or try to support multiple alignment masks,
but for now the easiest fix seems to be to turn the assert into a
bail-out check.
2019-11-21 Richard Sandiford
gcc/
PR tree-optimization/92526
* tree-vect-data-refs.c (vect_enhance_data_refs_alignment): Reject
versioning for alignment if the accesses do not have a consistent
mask, rather than asserting that the masks are consistent.
gcc/testsuite/
PR tree-optimization/92526
* gcc.target/aarch64/pr92526.c: New test.
Added:
trunk/gcc/testsuite/gcc.target/aarch64/pr92526.c
Modified:
trunk/gcc/ChangeLog
trunk/gcc/testsuite/ChangeLog
trunk/gcc/tree-vect-data-refs.c
