re PR middle-end/27781 (weak-attribute over-optimisation)

2006-06-16  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/27781
	* Makefile.in (ipa-pure-const.o): Add $(TARGET_H) dependency.
	* ipa-pure-const.c (target.h): Include.
	(analyze_function): Do not analyze functions that do not
        bind locally.

	* gcc.dg/tree-ssa/pr27781.c: New testcase.

From-SVN: r114681

gcc/ChangeLog

+2006-06-16  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/27781
+	* Makefile.in (ipa-pure-const.o): Add $(TARGET_H) dependency.
+	* ipa-pure-const.c (target.h): Include.
+	(analyze_function): Do not analyze functions that do not
+	bind locally.
+
 2006-06-15  Andrew MacLeod  <amacleod@redhat.com>
 	
 	PR middle-end/27793

gcc/Makefile.in

@@ -2309,7 +2309,7 @@ ipa-reference.o : ipa-reference.c $(CONFIG_H) $(SYSTEM_H) \
    $(TREE_GIMPLE_H) $(CGRAPH_H) output.h $(FLAGS_H) tree-pass.h $(DIAGNOSTIC_H)  
 ipa-pure-const.o : ipa-pure-const.c $(CONFIG_H) $(SYSTEM_H) \
    coretypes.h $(TM_H) $(TREE_H) $(TREE_FLOW_H) $(TREE_INLINE_H) langhooks.h \
-   pointer-set.h $(GGC_H) $(IPA_UTILS_H) $(C_COMMON_H) \
+   pointer-set.h $(GGC_H) $(IPA_UTILS_H) $(C_COMMON_H) $(TARGET_H) \
    $(TREE_GIMPLE_H) $(CGRAPH_H) output.h $(FLAGS_H) tree-pass.h $(DIAGNOSTIC_H)  
 ipa-type-escape.o : ipa-type-escape.c $(CONFIG_H) $(SYSTEM_H) \
    coretypes.h $(TM_H) $(TREE_H) $(TREE_FLOW_H) $(TREE_INLINE_H) langhooks.h \

gcc/ipa-pure-const.c

@@ -51,6 +51,7 @@ Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
 #include "timevar.h"
 #include "diagnostic.h"
 #include "langhooks.h"
+#include "target.h"
 
 static struct pointer_set_t *visited_nodes;
 
@@ -499,9 +500,11 @@ analyze_function (struct cgraph_node *fn)
   l->pure_const_state = IPA_CONST;
   l->state_set_in_source = false;
 
-  /* If this is a volatile function, do not touch this unless it has
-     been marked as const or pure by the front end.  */
-  if (TREE_THIS_VOLATILE (decl))
+  /* If this function does not return normally or does not bind local,
+     do not touch this unless it has been marked as const or pure by the
+     front end.  */
+  if (TREE_THIS_VOLATILE (decl)
+      || !targetm.binds_local_p (decl))
     {
       l->pure_const_state = IPA_NEITHER;
       return;

gcc/testsuite/ChangeLog

+2006-06-16  Richard Guenther  <rguenther@suse.de>
+
+	PR tree-optimization/27781
+	* gcc.dg/tree-ssa/pr27781.c: New testcase.
+
 2006-06-15  Thomas Koenig <Thomas.Koenig@online.de>
 
 	* gfortran.dg/allocate_zerosize_2.f90:  New test case.

gcc/testsuite/gcc.dg/tree-ssa/pr27781.c

+/* { dg-do compile } */
+/* { dg-require-weak "" } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+void __attribute__((weak)) func(void)
+{
+    /* no code */
+}
+
+int main()
+{
+    func();
+    return 0;
+}
+
+/* { dg-final { scan-tree-dump "func \\(\\);" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */