re PR tree-optimization/35494 (Revision 132991 breaks C++ static member)

gcc/

2008-03-10  H.J. Lu  <hongjiu.lu@intel.com>

	PR tree-optimization/35494
	* tree-ssa-ccp.c (get_symbol_constant_value): Check if value
	may be overriden at link and run time.

gcc/testsuite/

2008-03-10  H.J. Lu  <hongjiu.lu@intel.com>

	PR tree-optimization/35494
	* g++.dg/tree-ssa/ssa-store-ccp-1.C: New.
	* gcc.dg/tree-ssa/ssa-store-ccp-2.c: Likewise.
	* gcc.dg/tree-ssa/ssa-store-ccp-3.c: Likewise.
	* gcc.dg/tree-ssa/ssa-store-ccp-4.c: Likewise.

From-SVN: r133082

7 files changed, 80 insertions, 14 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 21ec0bd..9d3ba56 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2008-03-10  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR tree-optimization/35494
+	* tree-ssa-ccp.c (get_symbol_constant_value): Check if value
+	may be overriden at link and run time.
+
 2008-03-10  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/34677
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 98466dc..693a2a1 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,19 +1,14 @@
+2008-03-10  H.J. Lu  <hongjiu.lu@intel.com>
+
+	PR tree-optimization/35494
+	* g++.dg/tree-ssa/ssa-store-ccp-1.C: New.
+	* gcc.dg/tree-ssa/ssa-store-ccp-2.c: Likewise.
+	* gcc.dg/tree-ssa/ssa-store-ccp-3.c: Likewise.
+	* gcc.dg/tree-ssa/ssa-store-ccp-4.c: Likewise.
+
 2008-03-10  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/34677
-	* tree-ssa-pre.c (modify_expr_node_pool): Remove.
-	(poolify_tree): Likewise.
-	(modify_expr_template): Likewise.
-	(poolify_modify_stmt): Likewise.
-	(insert_fake_stores): Handle all component-ref style stores
-	in addition to INDIRECT_REF.  Also handle complex types.
-	Do not poolify the inserted load.
-	(realify_fake_stores): Do not rebuild the tree but only
-	make it a SSA_NAME copy.
-	(init_pre): Remove initialzation of modify_expr_template.
-	Do not allocate modify_expr_node_pool.
-	(fini_pre): Do not free modify_expr_node_pool.
-
 	* gcc.dg/tree-ssa/loadpre23.c: New testcase.
 	* gcc.dg/tree-ssa/loadpre24.c: Likewise.
 	* gcc.dg/tree-ssa/loadpre25.c: Likewise.
diff --git a/gcc/testsuite/g++.dg/tree-ssa/ssa-store-ccp-1.C b/gcc/testsuite/g++.dg/tree-ssa/ssa-store-ccp-1.C
new file mode 100644
index 0000000..06e9b1e
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tree-ssa/ssa-store-ccp-1.C
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+class bar
+{
+public:
+  static const int conststaticvariable;
+};
+
+
+int f(void)
+{
+  return bar::conststaticvariable;
+}
+
+/* There should be a reference to conststaticvariable since it may
+   be overriden at link time.  */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-2.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-2.c
new file mode 100644
index 0000000..be37a21
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-2.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be a reference to conststaticvariable since it may
+   may be overriden at link time.  */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c
new file mode 100644
index 0000000..2f028a2
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-3.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-common -fdump-tree-optimized" } */
+
+const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be no reference to conststaticvariable as we should have
+   inlined the 0. */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 0 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-4.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-4.c
new file mode 100644
index 0000000..cbf8bab
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-store-ccp-4.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target fpic } */
+/* { dg-options "-O2 -fno-common -fpic -fdump-tree-optimized" } */
+
+const int conststaticvariable;
+
+int f(void)
+{
+  return conststaticvariable;
+}
+
+/* There should be a reference to conststaticvariable since it may
+   may be overriden at run time.  */
+/* { dg-final { scan-tree-dump-times "conststaticvariable" 1 "optimized"} } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index b9211a5..7cefbf8 100644
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -300,7 +300,10 @@ get_symbol_constant_value (tree sym)
 {
   if (TREE_STATIC (sym)
       && TREE_READONLY (sym)
-      && !MTAG_P (sym))
+      && !MTAG_P (sym)
+      /* Check if a read-only definition may be overridden at
+	 link and run time.  */
+      && targetm.binds_local_p (sym))
     {
       tree val = DECL_INITIAL (sym);
       if (val