re PR tree-optimization/43879 (-fipa-pta causes various miscompilations)

2010-04-30  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/43879
	* tree-ssa-structalias.c (get_constraint_for_1): Properly
	handle non-zero initializers.

	* gcc.dg/torture/pr43879_1.c: New testcase.

From-SVN: r158924

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d20e202253c2c905d23e981a0c3ecea196e2a0f0..936a83861376156b1fd7b8bbacdb858222645b43 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-04-30  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/43879
+       * tree-ssa-structalias.c (get_constraint_for_1): Properly
+       handle non-zero initializers.
+
 2010-04-30  Richard Guenther  <rguenther@suse.de>
 
        * builtins.c (fold_builtin_1): Delete free (0).

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index cf678b87ef39b313d4b90230570821258a12a10d..f3284dc07adce5495c91ee24c3e3b0a0ea65460a 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-04-30  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/43879
+       * gcc.dg/torture/pr43879_1.c: New testcase.
+
 2010-04-30  Richard Guenther  <rguenther@suse.de>
 
        * gcc.dg/tree-ssa/builtin-free.c: New testcase.

diff --git a/gcc/testsuite/gcc.dg/torture/pr43879_1.c b/gcc/testsuite/gcc.dg/torture/pr43879_1.c
new file mode 100644 (file)
index 0000000..151a184
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr43879_1.c
@@ -0,0 +1,27 @@
+/* { dg-do run } */
+/* { dg-options "-fipa-pta" } */
+/* { dg-additional-sources "pr43879_2.c" } */
+
+void bar(int c)
+{
+       static int x = 1;
+       if (c != x) __builtin_abort();
+       x--;
+}
+
+void baz(int *i)
+{
+       (*i)--;
+}
+
+struct TBL {
+       int (*p)(int *i);
+};
+extern struct TBL tbl;
+
+int main()
+{
+       int c = 1;
+       return tbl.p(&c);
+}
+

diff --git a/gcc/testsuite/gcc.dg/torture/pr43879_2.c b/gcc/testsuite/gcc.dg/torture/pr43879_2.c
new file mode 100644 (file)
index 0000000..8155653
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr43879_2.c
@@ -0,0 +1,17 @@
+struct TBL {
+       int (*p)(int *i);
+};
+
+extern void bar(int i);
+extern void baz(int *i);
+
+static int foo(int *i)
+{
+       bar(*i);
+       baz(i);
+       bar(*i);
+       return *i;
+}
+
+struct TBL tbl = { foo };
+

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 08d3fa7e15b2f5034590525ffaec1af9746ea27d..928dc04d131daff81894efb37d0068779d5058b6 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -3285,8 +3285,10 @@ get_constraint_for_1 (tree t, VEC (ce_s, heap) **results, bool address_p)
       && ((TREE_CODE (t) == INTEGER_CST
           && integer_zerop (t))
          /* The only valid CONSTRUCTORs in gimple with pointer typed
-            elements are zero-initializer.  */
-         || TREE_CODE (t) == CONSTRUCTOR))
+            elements are zero-initializer.  But in IPA mode we also
+            process global initializers, so verify at least.  */
+         || (TREE_CODE (t) == CONSTRUCTOR
+             && CONSTRUCTOR_NELTS (t) == 0)))
     {
       temp.var = nothing_id;
       temp.type = ADDRESSOF;