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| author | Richard Guenther <rguenther@suse.de> | 2012-03-14 13:00:44 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2012-03-14 13:00:44 +0000 |
| commit | c205d0b3f5d47699977946add69e4409898d5cbc (patch) | |
| tree | aba8befd3c64b2c2d7015e8c092e44778329671f /gcc/tree-vect-data-refs.c | |
| parent | 26c71b9368c1ef1929205fe1aafab1748640596b (diff) | |
| download | gcc-c205d0b3f5d47699977946add69e4409898d5cbc.zip gcc-c205d0b3f5d47699977946add69e4409898d5cbc.tar.gz gcc-c205d0b3f5d47699977946add69e4409898d5cbc.tar.bz2 | |
re PR tree-optimization/52571 (vectorizer changes alignment of common symbols)
2012-03-14 Richard Guenther <rguenther@suse.de>
PR tree-optimization/52571
* tree-vect-data-refs.c (vect_compute_data_ref_alignment): Move
flag_section_anchors check ...
(vect_can_force_dr_alignment_p): ... here. Do not re-align
DECL_COMMON variables.
* gcc.dg/vect/vect-2.c: Initialize arrays.
* gcc.dg/vect/no-section-anchors-vect-34.c: Likewise.
* gcc.target/i386/recip-vec-divf.c: Use -fno-common.
* gcc.target/i386/recip-vec-sqrtf.c: Likewise.
From-SVN: r185380
Diffstat (limited to 'gcc/tree-vect-data-refs.c')
| -rw-r--r-- | gcc/tree-vect-data-refs.c | 17 |
1 files changed, 12 insertions, 5 deletions
diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c index b458d62..9b66d86 100644 --- a/gcc/tree-vect-data-refs.c +++ b/gcc/tree-vect-data-refs.c @@ -872,10 +872,7 @@ vect_compute_data_ref_alignment (struct data_reference *dr) if (!base_aligned) { - /* Do not change the alignment of global variables if - flag_section_anchors is enabled. */ - if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype)) - || (TREE_STATIC (base) && flag_section_anchors)) + if (!vect_can_force_dr_alignment_p (base, TYPE_ALIGN (vectype))) { if (vect_print_dump_info (REPORT_DETAILS)) { @@ -4546,12 +4543,22 @@ vect_can_force_dr_alignment_p (const_tree decl, unsigned int alignment) if (TREE_CODE (decl) != VAR_DECL) return false; - if (DECL_EXTERNAL (decl)) + /* We cannot change alignment of common or external symbols as another + translation unit may contain a definition with lower alignment. + The rules of common symbol linking mean that the definition + will override the common symbol. */ + if (DECL_EXTERNAL (decl) + || DECL_COMMON (decl)) return false; if (TREE_ASM_WRITTEN (decl)) return false; + /* Do not change the alignment of global variables if flag_section_anchors + is enabled. */ + if (TREE_STATIC (decl) && flag_section_anchors) + return false; + if (TREE_STATIC (decl)) return (alignment <= MAX_OFILE_ALIGNMENT); else |