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| author | Richard Biener <rguenther@suse.de> | 2014-10-10 11:17:13 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2014-10-10 11:17:13 +0000 |
| commit | f1485e5b24f83af957e3d528dc80cd88b67acdc5 (patch) | |
| tree | dcad327648e25cff091d2c3a264b952d5ec44924 /gcc/tree-vect-slp.c | |
| parent | 18cda88d873b67cfa06ac2a9c8b2e85468a73f4c (diff) | |
| download | gcc-f1485e5b24f83af957e3d528dc80cd88b67acdc5.zip gcc-f1485e5b24f83af957e3d528dc80cd88b67acdc5.tar.gz gcc-f1485e5b24f83af957e3d528dc80cd88b67acdc5.tar.bz2 | |
re PR tree-optimization/63379 (Incorrect vectorization when enabling SSE and O3, initialises loop with wrong value)
2014-10-10 Richard Biener <rguenther@suse.de>
PR tree-optimization/63379
* tree-vect-slp.c (vect_get_constant_vectors): Do not compute
a neutral operand for min/max when it is not a reduction chain.
* gcc.dg/vect/pr63379.c: New testcase.
From-SVN: r216070
Diffstat (limited to 'gcc/tree-vect-slp.c')
| -rw-r--r-- | gcc/tree-vect-slp.c | 22 |
1 files changed, 15 insertions, 7 deletions
diff --git a/gcc/tree-vect-slp.c b/gcc/tree-vect-slp.c index d48d3f5..5984229 100644 --- a/gcc/tree-vect-slp.c +++ b/gcc/tree-vect-slp.c @@ -2395,13 +2395,21 @@ vect_get_constant_vectors (tree op, slp_tree slp_node, neutral_op = build_int_cst (TREE_TYPE (op), -1); break; - case MAX_EXPR: - case MIN_EXPR: - def_stmt = SSA_NAME_DEF_STMT (op); - loop = (gimple_bb (stmt))->loop_father; - neutral_op = PHI_ARG_DEF_FROM_EDGE (def_stmt, - loop_preheader_edge (loop)); - break; + /* For MIN/MAX we don't have an easy neutral operand but + the initial values can be used fine here. Only for + a reduction chain we have to force a neutral element. */ + case MAX_EXPR: + case MIN_EXPR: + if (!GROUP_FIRST_ELEMENT (stmt_vinfo)) + neutral_op = NULL; + else + { + def_stmt = SSA_NAME_DEF_STMT (op); + loop = (gimple_bb (stmt))->loop_father; + neutral_op = PHI_ARG_DEF_FROM_EDGE (def_stmt, + loop_preheader_edge (loop)); + } + break; default: neutral_op = NULL; |