* gcc.dg/20040910-1.c, gcc.dg/cpp/digraph2.c,

[pf3gnuchains/gcc-fork.git] / gcc / tree-ssa-copy.c

diff --git a/gcc/tree-ssa-copy.c b/gcc/tree-ssa-copy.c
index 611bae7..e7f51c5 100644 (file)
--- a/gcc/tree-ssa-copy.c
+++ b/gcc/tree-ssa-copy.c
@@ -112,8 +112,8 @@ may_propagate_copy (tree dest, tree orig)
        return false;
       else if (!lang_hooks.types_compatible_p (type_d, type_o))
        return false;
-      else if (!alias_sets_conflict_p (get_alias_set (TREE_TYPE (type_d)),
-                                      get_alias_set (TREE_TYPE (type_o))))
+      else if (get_alias_set (TREE_TYPE (type_d)) != 
+              get_alias_set (TREE_TYPE (type_o)))
        return false;
     }
 
@@ -145,17 +145,27 @@ may_propagate_copy (tree dest, tree orig)
       && 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 DEST is an SSA_NAME that flows from an abnormal edge, 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))))
+      && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (dest))
     return false;
 
   /* Anything else is OK.  */
   return true;
 }
 
+/* Similarly, but we know that we're propagating into an ASM_EXPR.  */
+
+bool
+may_propagate_copy_into_asm (tree dest)
+{
+  /* Hard register operands of asms are special.  Do not bypass.  */
+  return !(TREE_CODE (dest) == SSA_NAME
+          && TREE_CODE (SSA_NAME_VAR (dest)) == VAR_DECL
+          && DECL_HARD_REGISTER (SSA_NAME_VAR (dest)));
+}
+
 
 /* Given two SSA_NAMEs pointers ORIG and NEW such that we are copy
    propagating NEW into ORIG, consolidate aliasing information so that
@@ -168,6 +178,8 @@ merge_alias_info (tree orig, tree new)
   tree orig_sym = SSA_NAME_VAR (orig);
   var_ann_t new_ann = var_ann (new_sym);
   var_ann_t orig_ann = var_ann (orig_sym);
+  struct ptr_info_def *new_ptr_info;
+  struct ptr_info_def *orig_ptr_info;
 
   gcc_assert (POINTER_TYPE_P (TREE_TYPE (orig)));
   gcc_assert (POINTER_TYPE_P (TREE_TYPE (new)));
@@ -182,14 +194,28 @@ merge_alias_info (tree orig, tree new)
              == get_alias_set (TREE_TYPE (TREE_TYPE (orig_sym))));
 #endif
 
-  /* Merge type-based alias info.  */
+  /* Synchronize the type tags.  If both pointers had a tag and they
+     are different, then something has gone wrong.  */
   if (new_ann->type_mem_tag == NULL_TREE)
     new_ann->type_mem_tag = orig_ann->type_mem_tag;
   else if (orig_ann->type_mem_tag == NULL_TREE)
     orig_ann->type_mem_tag = new_ann->type_mem_tag;
   else
     gcc_assert (new_ann->type_mem_tag == orig_ann->type_mem_tag);
-}
+
+  /* Synchronize flow sensitive alias information.  If both pointers
+     had flow information and they are inconsistent, then something
+     has gone wrong.  */
+  new_ptr_info = get_ptr_info (new);
+  orig_ptr_info = get_ptr_info (orig);
+
+  if (new_ptr_info->name_mem_tag == NULL_TREE)
+    memcpy (new_ptr_info, orig_ptr_info, sizeof (*new_ptr_info));
+  else if (orig_ptr_info->name_mem_tag == NULL_TREE)
+    memcpy (orig_ptr_info, new_ptr_info, sizeof (*orig_ptr_info));
+  else if (orig_ptr_info->name_mem_tag != new_ptr_info->name_mem_tag)
+    abort ();
+}   
 
 
 /* Common code for propagate_value and replace_exp.