+2010-06-10 Martin Jambor <mjambor@suse.cz>
+
+ PR tree-optimization/44258
+ * tree-sra.c (build_access_subtree): Return false iff there is a
+ partial overlap.
+ (build_access_trees): Likewise.
+ (analyze_all_variable_accesses): Disqualify candidates if
+ build_access_trees returns true for them.
+
2010-06-10 Alexandre Oliva <aoliva@redhat.com>
PR debug/41371
--- /dev/null
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-esra-details" } */
+
+struct blah
+{
+ char a[4];
+};
+
+struct str
+{
+ struct blah b1;
+ char x;
+};
+
+struct val
+{
+ char y;
+ struct blah b2;
+};
+
+union U
+{
+ struct str str;
+ struct val val;
+};
+
+
+extern struct blah e_b1, e_b2;
+extern union U *e_u;
+
+int foo (int b)
+{
+ union U u;
+
+ u.str.b1 = e_b1;
+ u.val.b2 = e_b2;
+ u.str.b1.a[3] = 0;
+
+ *e_u = u;
+}
+
+/* { dg-final { scan-tree-dump-times "Created a replacement" 0 "esra"} } */
+/* { dg-final { cleanup-tree-dump "esra" } } */
/* Build a subtree of accesses rooted in *ACCESS, and move the pointer in the
linked list along the way. Stop when *ACCESS is NULL or the access pointed
- to it is not "within" the root. */
+ to it is not "within" the root. Return false iff some accesses partially
+ overlap. */
-static void
+static bool
build_access_subtree (struct access **access)
{
struct access *root = *access, *last_child = NULL;
last_child->next_sibling = *access;
last_child = *access;
- build_access_subtree (access);
+ if (!build_access_subtree (access))
+ return false;
}
+
+ if (*access && (*access)->offset < limit)
+ return false;
+
+ return true;
}
/* Build a tree of access representatives, ACCESS is the pointer to the first
- one, others are linked in a list by the next_grp field. Decide about scalar
- replacements on the way, return true iff any are to be created. */
+ one, others are linked in a list by the next_grp field. Return false iff
+ some accesses partially overlap. */
-static void
+static bool
build_access_trees (struct access *access)
{
while (access)
{
struct access *root = access;
- build_access_subtree (&access);
+ if (!build_access_subtree (&access))
+ return false;
root->next_grp = access;
}
+ return true;
}
/* Return true if expr contains some ARRAY_REFs into a variable bounded
struct access *access;
access = sort_and_splice_var_accesses (var);
- if (access)
- build_access_trees (access);
- else
+ if (!access || !build_access_trees (access))
disqualify_candidate (var,
"No or inhibitingly overlapping accesses.");
}