PR tree-optimization/16688

	PR tree-optimization/16689
	* tree-ssa-alias.c (setup_pointers_and_addressables): Remove
	unnecessary initialization of 'tag'.
	(get_tmt_for): Check that the new type tag has the same alias
	set as the pointed-to type.
	(group_aliases): Only regular variables need to be removed
	from the alias set of a name tag.
	* tree-ssa-copy.c (may_propagate_copy): Do not allow copy
	propagation if the two types are not compatible.
	(merge_alias_info): Rename from replace_ssa_names_ann.
	Add more checking.
	(replace_exp_1): If both arguments are SSA_NAMEs, check that
	the propagation can be done.
	Only call merge_alias_info on pointers.
	(propagate_value): Likewise.
	* tree-ssa-copyrename.c: Include langhooks.h.
	(copy_rename_partition_coalesce): Call replace_ssa_name_symbol
	to do the merging.
	Do not coalesce variables with incompatible types.
	(rename_ssa_copies): Call replace_ssa_name_symbol.
	* tree-ssa.c (verify_ssa_name): Verify that the SSA_NAME has
	the same type as the underlying _DECL.
	* tree-ssanames.c (replace_ssa_name_symbol): New function.
	* tree.h (replace_ssa_name_symbol): Declare.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@85108 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 12 insertions, 3 deletions

diff --git a/gcc/tree-ssa-copyrename.c b/gcc/tree-ssa-copyrename.c
index c65b8284de6..ac7c00aa06e 100644
--- a/gcc/tree-ssa-copyrename.c
+++ b/gcc/tree-ssa-copyrename.c
@@ -38,6 +38,7 @@ Boston, MA 02111-1307, USA.  */
 #include "tree-dump.h"
 #include "tree-ssa-live.h"
 #include "tree-pass.h"
+#include "langhooks.h"
 
 extern void rename_ssa_copies (void);
 
@@ -247,16 +248,24 @@ copy_rename_partition_coalesce (var_map map, tree var1, tree var2, FILE *debug)
 	gimp2 = false;
       }
 
+  /* Don't coalesce if the two variables aren't type compatible.  */
+  if (!lang_hooks.types_compatible_p (TREE_TYPE (root1), TREE_TYPE (root2)))
+    {
+      if (debug)
+	fprintf (debug, " : Incompatible types.  No coalesce.\n");
+      return;
+    }
+
   /* Merge the two partitions.  */
   p3 = partition_union (map->var_partition, p1, p2);
 
   /* Set the root variable of the partition to the better choice, if there is 
      one.  */
   if (!gimp2)
-    SSA_NAME_VAR (partition_to_var (map, p3)) = root2;
+    replace_ssa_name_symbol (partition_to_var (map, p3), root2);
   else
     if (!gimp1)
-      SSA_NAME_VAR (partition_to_var (map, p3)) = root1;
+      replace_ssa_name_symbol (partition_to_var (map, p3), root1);
 
   /* Update the various flag widgitry of the current base representative.  */
   ann3 = var_ann (SSA_NAME_VAR (partition_to_var (map, p3)));
@@ -359,7 +368,7 @@ rename_ssa_copies (void)
 	      fprintf (debug, "\n");
 	    }
 	}
-      SSA_NAME_VAR (var) = SSA_NAME_VAR (part_var);
+      replace_ssa_name_symbol (var, SSA_NAME_VAR (part_var));
     }
 
   delete_var_map (map);