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authorrguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4>2014-08-15 07:50:40 +0000
committerrguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4>2014-08-15 07:50:40 +0000
commitc8efcccb4e34afdc38a9271ac15ed6538a55dccb (patch)
treed715e9fb4a2949aee3ce02f70c58ffb10d618df5 /gcc/tree-data-ref.c
parentd2aa25da6928a813e6dcf4437496bfb0baa77d57 (diff)
downloadgcc-c8efcccb4e34afdc38a9271ac15ed6538a55dccb.tar.gz
2014-08-15 Richard Biener <rguenther@suse.de>
PR tree-optimization/62031 * tree-data-ref.c (dr_analyze_indices): Do not set DR_UNCONSTRAINED_BASE. (dr_may_alias_p): All indirect accesses have to go the formerly DR_UNCONSTRAINED_BASE path. * tree-data-ref.h (struct indices): Remove unconstrained_base member. (DR_UNCONSTRAINED_BASE): Remove. * gcc.dg/torture/pr62031.c: New testcase. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@214006 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/tree-data-ref.c')
-rw-r--r--gcc/tree-data-ref.c37
1 files changed, 27 insertions, 10 deletions
diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index 55dbf6a65d3..1d3efa67813 100644
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -982,7 +982,6 @@ dr_analyze_indices (struct data_reference *dr, loop_p nest, loop_p loop)
ref = fold_build2_loc (EXPR_LOCATION (ref),
MEM_REF, TREE_TYPE (ref),
base, memoff);
- DR_UNCONSTRAINED_BASE (dr) = true;
access_fns.safe_push (access_fn);
}
}
@@ -1389,14 +1388,20 @@ dr_may_alias_p (const struct data_reference *a, const struct data_reference *b,
return false;
}
- /* If we had an evolution in a MEM_REF BASE_OBJECT we do not know
- the size of the base-object. So we cannot do any offset/overlap
- based analysis but have to rely on points-to information only. */
+ /* If we had an evolution in a pointer-based MEM_REF BASE_OBJECT we
+ do not know the size of the base-object. So we cannot do any
+ offset/overlap based analysis but have to rely on points-to
+ information only. */
if (TREE_CODE (addr_a) == MEM_REF
- && DR_UNCONSTRAINED_BASE (a))
+ && TREE_CODE (TREE_OPERAND (addr_a, 0)) == SSA_NAME)
{
- if (TREE_CODE (addr_b) == MEM_REF
- && DR_UNCONSTRAINED_BASE (b))
+ /* For true dependences we can apply TBAA. */
+ if (flag_strict_aliasing
+ && DR_IS_WRITE (a) && DR_IS_READ (b)
+ && !alias_sets_conflict_p (get_alias_set (DR_REF (a)),
+ get_alias_set (DR_REF (b))))
+ return false;
+ if (TREE_CODE (addr_b) == MEM_REF)
return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0),
TREE_OPERAND (addr_b, 0));
else
@@ -1404,9 +1409,21 @@ dr_may_alias_p (const struct data_reference *a, const struct data_reference *b,
build_fold_addr_expr (addr_b));
}
else if (TREE_CODE (addr_b) == MEM_REF
- && DR_UNCONSTRAINED_BASE (b))
- return ptr_derefs_may_alias_p (build_fold_addr_expr (addr_a),
- TREE_OPERAND (addr_b, 0));
+ && TREE_CODE (TREE_OPERAND (addr_b, 0)) == SSA_NAME)
+ {
+ /* For true dependences we can apply TBAA. */
+ if (flag_strict_aliasing
+ && DR_IS_WRITE (a) && DR_IS_READ (b)
+ && !alias_sets_conflict_p (get_alias_set (DR_REF (a)),
+ get_alias_set (DR_REF (b))))
+ return false;
+ if (TREE_CODE (addr_a) == MEM_REF)
+ return ptr_derefs_may_alias_p (TREE_OPERAND (addr_a, 0),
+ TREE_OPERAND (addr_b, 0));
+ else
+ return ptr_derefs_may_alias_p (build_fold_addr_expr (addr_a),
+ TREE_OPERAND (addr_b, 0));
+ }
/* Otherwise DR_BASE_OBJECT is an access that covers the whole object
that is being subsetted in the loop nest. */