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| author | Richard Biener <rguenther@suse.de> | 2016-11-07 08:05:08 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2016-11-07 08:05:08 +0000 |
| commit | a0d3edf8a54e30d48f61eb59a0be33c7ed2b971f (patch) | |
| tree | ef5f5054bbe0f2fc255f9f42ab020ae3580c96fa /gcc/tree-vect-data-refs.c | |
| parent | e34b855ed55fc5bb99aeaf013c64db98eb333ca0 (diff) | |
| download | gcc-a0d3edf8a54e30d48f61eb59a0be33c7ed2b971f.zip gcc-a0d3edf8a54e30d48f61eb59a0be33c7ed2b971f.tar.gz gcc-a0d3edf8a54e30d48f61eb59a0be33c7ed2b971f.tar.bz2 | |
re PR tree-optimization/78189 (movaps generated for unaligned store in aligned struct, when struct is referenced via unaligned member.)
2016-11-07 Richard Biener <rguenther@suse.de>
PR tree-optimization/78189
* tree-vect-data-refs.c (vect_compute_data_ref_alignment): Fix
alignment computation.
* g++.dg/torture/pr78189.C: New testcase.
From-SVN: r241892
Diffstat (limited to 'gcc/tree-vect-data-refs.c')
| -rw-r--r-- | gcc/tree-vect-data-refs.c | 21 |
1 files changed, 18 insertions, 3 deletions
diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c index 9346cfe..b03cb1e 100644 --- a/gcc/tree-vect-data-refs.c +++ b/gcc/tree-vect-data-refs.c @@ -773,10 +773,25 @@ vect_compute_data_ref_alignment (struct data_reference *dr) base = ref; while (handled_component_p (base)) base = TREE_OPERAND (base, 0); + unsigned int base_alignment; + unsigned HOST_WIDE_INT base_bitpos; + get_object_alignment_1 (base, &base_alignment, &base_bitpos); + /* As data-ref analysis strips the MEM_REF down to its base operand + to form DR_BASE_ADDRESS and adds the offset to DR_INIT we have to + adjust things to make base_alignment valid as the alignment of + DR_BASE_ADDRESS. */ if (TREE_CODE (base) == MEM_REF) - base = build2 (MEM_REF, TREE_TYPE (base), base_addr, - build_int_cst (TREE_TYPE (TREE_OPERAND (base, 1)), 0)); - unsigned int base_alignment = get_object_alignment (base); + { + base_bitpos -= mem_ref_offset (base).to_short_addr () * BITS_PER_UNIT; + base_bitpos &= (base_alignment - 1); + } + if (base_bitpos != 0) + base_alignment = base_bitpos & -base_bitpos; + /* Also look at the alignment of the base address DR analysis + computed. */ + unsigned int base_addr_alignment = get_pointer_alignment (base_addr); + if (base_addr_alignment > base_alignment) + base_alignment = base_addr_alignment; if (base_alignment >= TYPE_ALIGN (TREE_TYPE (vectype))) DR_VECT_AUX (dr)->base_element_aligned = true; |