* tree-flow-inline.h (may_propagate_copy): Move...

        * tree-ssa-copy.c (may_propagate_copy): ... here.  Fail if we
        attempt to copy between types requiring conversion.
        * tree-flow.h (may_propagate_copy): Update decl.
        * tree-ssa-dom.c (cprop_operand): Tidy redundant tests.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@84225 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 0 insertions, 91 deletions

diff --git a/gcc/tree-flow-inline.h b/gcc/tree-flow-inline.h
index bda65ca7f5c..e68e63eb8ed 100644
--- a/gcc/tree-flow-inline.h
+++ b/gcc/tree-flow-inline.h
@@ -467,97 +467,6 @@ is_label_stmt (tree t)
   return false;
 }
 
-/* Return true if we may propagate ORIG into DEST, false otherwise.  */
-static inline bool
-may_propagate_copy (tree dest, tree orig)
-{
-  /* FIXME.  GIMPLE is allowing pointer assignments and comparisons of
-     pointers that have different alias sets.  This means that these
-     pointers will have different memory tags associated to them.
-     
-     If we allow copy propagation in these cases, statements de-referencing
-     the new pointer will now have a reference to a different memory tag
-     with potentially incorrect SSA information.
-
-     This was showing up in libjava/java/util/zip/ZipFile.java with code
-     like:
-
-     	struct java.io.BufferedInputStream *T.660;
-	struct java.io.BufferedInputStream *T.647;
-	struct java.io.InputStream *is;
-	struct java.io.InputStream *is.662;
-	[ ... ]
-	T.660 = T.647;
-	is = T.660;	<-- This ought to be type-casted
-	is.662 = is;
-
-     Also, f/name.c exposed a similar problem with a COND_EXPR predicate
-     that was causing DOM to generate and equivalence with two pointers of
-     alias-incompatible types:
-
-     	struct _ffename_space *n;
-	struct _ffename *ns;
-	[ ... ]
-	if (n == ns)
-	  goto lab;
-	...
-	lab:
-	return n;
-
-     I think that GIMPLE should emit the appropriate type-casts.  For the
-     time being, blocking copy-propagation in these cases is the safe thing
-     to do.  */
-  if (TREE_CODE (dest) == SSA_NAME
-      && TREE_CODE (orig) == SSA_NAME
-      && POINTER_TYPE_P (TREE_TYPE (dest))
-      && POINTER_TYPE_P (TREE_TYPE (orig)))
-    {
-      tree mt_dest = var_ann (SSA_NAME_VAR (dest))->type_mem_tag;
-      tree mt_orig = var_ann (SSA_NAME_VAR (orig))->type_mem_tag;
-      if (mt_dest && mt_orig && mt_dest != mt_orig)
-	return false;
-    }
-
-  /* If the destination is a SSA_NAME for a virtual operand, then we have
-     some special cases to handle.  */
-  if (TREE_CODE (dest) == SSA_NAME && !is_gimple_reg (dest))
-    {
-      /* If both operands are SSA_NAMEs referring to virtual operands, then
-	 we can always propagate.  */
-      if (TREE_CODE (orig) == SSA_NAME)
-	{
-	  if (!is_gimple_reg (orig))
-	    return true;
-
-#ifdef ENABLE_CHECKING
-	  /* If we have one real and one virtual operand, then something has
-	     gone terribly wrong.  */
-	  if (is_gimple_reg (orig))
-	    abort ();
-#endif
-	}
-
-      /* We have a "copy" from something like a constant into a virtual
-	 operand.  Reject these.  */
-      return false;
-    }
-
-  /* If ORIG flows in from an abnormal edge, it cannot be propagated.  */
-  if (TREE_CODE (orig) == SSA_NAME
-      && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (orig))
-    return false;
-
-  /* If DEST is an SSA_NAME that flows from an abnormal edge or if it
-     represents a hard register, then it cannot be replaced.  */
-  if (TREE_CODE (dest) == SSA_NAME
-      && (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (dest)
-	  || DECL_HARD_REGISTER (SSA_NAME_VAR (dest))))
-    return false;
-
-  /* Anything else is OK.  */
-  return true;
-}
-
 /* Set the default definition for VAR to DEF.  */
 static inline void
 set_default_def (tree var, tree def)