function.h (struct function): Add cannot_be_copied_reason, and cannot_be_copied_set.

	* function.h (struct function): Add cannot_be_copied_reason,
	and cannot_be_copied_set.
	* tree-inline.c (has_label_address_in_static_1): Rename from
	inline_forbidden_p_2; don't set inline_forbidden_reason here.
	(cannot_copy_type_1): Rename from inline_forbidden_p_op; likewise
	don't set inline_forbidden_reason.
	(copy_forbidden): New function, split out of inline_forbidden_p.
	(inline_forbidden_p_stmt): Don't check for nonlocal labels here.
	(inline_forbidden_p): Use copy_forbidden.
	(tree_versionable_function_p): Likewise.
	(inlinable_function_p): Merge into tree_inlinable_function_p.
	(tree_function_versioning): Remap cfun->nonlocal_goto_save_area.
	* ipa-cp.c (ipcp_versionable_function_p): New function.
	(ipcp_cloning_candidate_p): Use it.
	(ipcp_node_modifiable_p): Likewise.

From-SVN: r148981

4 files changed, 182 insertions, 97 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 744aaf7..b01fbdd 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,21 @@
+2009-06-26  Richard Henderson  <rth@redhat.com>
+
+	* function.h (struct function): Add cannot_be_copied_reason,
+	and cannot_be_copied_set.
+	* tree-inline.c (has_label_address_in_static_1): Rename from
+	inline_forbidden_p_2; don't set inline_forbidden_reason here.
+	(cannot_copy_type_1): Rename from inline_forbidden_p_op; likewise
+	don't set inline_forbidden_reason.
+	(copy_forbidden): New function, split out of inline_forbidden_p.
+	(inline_forbidden_p_stmt): Don't check for nonlocal labels here.
+	(inline_forbidden_p): Use copy_forbidden.
+	(tree_versionable_function_p): Likewise.
+	(inlinable_function_p): Merge into tree_inlinable_function_p.
+	(tree_function_versioning): Remap cfun->nonlocal_goto_save_area.
+	* ipa-cp.c (ipcp_versionable_function_p): New function.
+	(ipcp_cloning_candidate_p): Use it.
+	(ipcp_node_modifiable_p): Likewise.
+
 2009-06-26  Olatunji Ruwase  <tjruwase@google.com>
 
 	* builtins.c (expand_builtin_alloca): Handle builtin alloca
diff --git a/gcc/function.h b/gcc/function.h
index de3a46a..8f69429 100644
--- a/gcc/function.h
+++ b/gcc/function.h
@@ -524,11 +524,17 @@ struct GTY(()) function {
   /* Properties used by the pass manager.  */
   unsigned int curr_properties;
   unsigned int last_verified;
+
   /* Interprocedural passes scheduled to have their transform functions
      applied next time we execute local pass on them.  We maintain it
      per-function in order to allow IPA passes to introduce new functions.  */
   VEC(ipa_opt_pass,heap) * GTY((skip)) ipa_transforms_to_apply;
 
+  /* Non-null if the function does something that would prevent it from
+     being copied; this applies to both versioning and inlining.  Set to
+     a string describing the reason for failure.  */
+  const char * GTY((skip)) cannot_be_copied_reason;
+
   /* Collected bit flags.  */
 
   /* Number of units of general registers that need saving in stdarg
@@ -540,7 +546,6 @@ struct GTY(()) function {
      function.  */
   unsigned int va_list_fpr_size : 8;
 
-
   /* How commonly executed the function is.  Initialized during branch
      probabilities pass.  */
   ENUM_BITFIELD (function_frequency) function_frequency : 2;
@@ -556,6 +561,11 @@ struct GTY(()) function {
      from nested functions.  */
   unsigned int has_nonlocal_label : 1;
 
+  /* Nonzero if we've set cannot_be_copied_reason.  I.e. if 
+     (cannot_be_copied_set && !cannot_be_copied_reason), the function
+     can in fact be copied.  */
+  unsigned int cannot_be_copied_set : 1;
+
   /* Nonzero if current function uses stdarg.h or equivalent.  */
   unsigned int stdarg : 1;
 
diff --git a/gcc/ipa-cp.c b/gcc/ipa-cp.c
index 581a88a..fe335c4 100644
--- a/gcc/ipa-cp.c
+++ b/gcc/ipa-cp.c
@@ -351,6 +351,45 @@ ipcp_print_all_lattices (FILE * f)
     }
 }
 
+/* Return true if ipcp algorithms would allow cloning NODE.  */
+
+static bool
+ipcp_versionable_function_p (struct cgraph_node *node)
+{
+  tree decl = node->decl;
+  basic_block bb;
+
+  /* There are a number of generic reasons functions cannot be versioned.  */
+  if (!tree_versionable_function_p (decl))
+    return false;
+
+  /* Removing arguments doesn't work if the function takes varargs.  */
+  if (DECL_STRUCT_FUNCTION (decl)->stdarg)
+    return false;
+
+  /* Removing arguments doesn't work if we use __builtin_apply_args.  */
+  FOR_EACH_BB_FN (bb, DECL_STRUCT_FUNCTION (decl))
+    {
+      gimple_stmt_iterator gsi;
+      for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+	{
+	  const_gimple stmt = gsi_stmt (gsi);
+	  tree t;
+
+	  if (!is_gimple_call (stmt))
+	    continue;
+	  t = gimple_call_fndecl (stmt);
+	  if (t == NULL_TREE)
+	    continue;
+	  if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL
+	      && DECL_FUNCTION_CODE (t) == BUILT_IN_APPLY_ARGS)
+	    return false;
+	}
+    }
+
+  return true;
+}
+
 /* Return true if this NODE is viable candidate for cloning.  */
 static bool
 ipcp_cloning_candidate_p (struct cgraph_node *node)
@@ -374,7 +413,7 @@ ipcp_cloning_candidate_p (struct cgraph_node *node)
  	         cgraph_node_name (node));
       return false;
     }
-  if (!tree_versionable_function_p (node->decl))
+  if (!ipcp_versionable_function_p (node))
     {
       if (dump_file)
         fprintf (dump_file, "Not considering %s for cloning; body is not versionable.\n",
@@ -677,7 +716,7 @@ ipcp_node_modifiable_p (struct cgraph_node *node)
 {
   /* Once we will be able to do in-place replacement, we can be more
      lax here.  */
-  return tree_versionable_function_p (node->decl);
+  return ipcp_versionable_function_p (node);
 }
 
 /* Print count scale data structures.  */
diff --git a/gcc/tree-inline.c b/gcc/tree-inline.c
index 052d341..b97b9b2 100644
--- a/gcc/tree-inline.c
+++ b/gcc/tree-inline.c
@@ -119,7 +119,6 @@ eni_weights eni_time_weights;
 /* Prototypes.  */
 
 static tree declare_return_variable (copy_body_data *, tree, tree, tree *);
-static bool inlinable_function_p (tree);
 static void remap_block (tree *, copy_body_data *);
 static void copy_bind_expr (tree *, int *, copy_body_data *);
 static tree mark_local_for_remap_r (tree *, int *, void *);
@@ -2436,26 +2435,32 @@ declare_return_variable (copy_body_data *id, tree return_slot, tree modify_dest,
   return var;
 }
 
-/* Returns nonzero if a function can be inlined as a tree.  */
+/* Callback through walk_tree.  Determine if a DECL_INITIAL makes reference
+   to a local label.  */
 
-bool
-tree_inlinable_function_p (tree fn)
+static tree
+has_label_address_in_static_1 (tree *nodep, int *walk_subtrees, void *fnp)
 {
-  return inlinable_function_p (fn);
-}
+  tree node = *nodep;
+  tree fn = (tree) fnp;
 
-static const char *inline_forbidden_reason;
+  if (TREE_CODE (node) == LABEL_DECL && DECL_CONTEXT (node) == fn)
+    return node;
+
+  if (TYPE_P (node))
+    *walk_subtrees = 0;
+
+  return NULL_TREE;
+}
 
-/* A callback for walk_gimple_seq to handle tree operands.  Returns
-   NULL_TREE if a function can be inlined, otherwise sets the reason
-   why not and returns a tree representing the offending operand. */
+/* Callback through walk_tree.  Determine if we've got an aggregate
+   type that we can't support; return non-null if so.  */
 
 static tree
-inline_forbidden_p_op (tree *nodep, int *walk_subtrees ATTRIBUTE_UNUSED,
-                         void *fnp ATTRIBUTE_UNUSED)
+cannot_copy_type_1 (tree *nodep, int *walk_subtrees ATTRIBUTE_UNUSED,
+                    void *data ATTRIBUTE_UNUSED)
 {
-  tree node = *nodep;
-  tree t;
+  tree t, node = *nodep;
 
   if (TREE_CODE (node) == RECORD_TYPE || TREE_CODE (node) == UNION_TYPE)
     {
@@ -2474,21 +2479,78 @@ inline_forbidden_p_op (tree *nodep, int *walk_subtrees ATTRIBUTE_UNUSED,
 	 cycle to try to find out.  This should be checked for 4.1.  */
       for (t = TYPE_FIELDS (node); t; t = TREE_CHAIN (t))
 	if (variably_modified_type_p (TREE_TYPE (t), NULL))
-	  {
-	    inline_forbidden_reason
-	      = G_("function %q+F can never be inlined "
-		   "because it uses variable sized variables");
-	    return node;
-	  }
+	  return node;
     }
 
   return NULL_TREE;
 }
 
 
-/* A callback for walk_gimple_seq to handle statements.  Returns
-   non-NULL iff a function can not be inlined.  Also sets the reason
-   why. */
+/* Determine if the function can be copied.  If so return NULL.  If
+   not return a string describng the reason for failure.  */
+
+static const char *
+copy_forbidden (struct function *fun, tree fndecl)
+{
+  const char *reason = fun->cannot_be_copied_reason;
+  tree step;
+
+  /* Only examine the function once.  */
+  if (fun->cannot_be_copied_set)
+    return reason;
+
+  /* We cannot copy a function that receives a non-local goto
+     because we cannot remap the destination label used in the
+     function that is performing the non-local goto.  */
+  /* ??? Actually, this should be possible, if we work at it.
+     No doubt there's just a handful of places that simply
+     assume it doesn't happen and don't substitute properly.  */
+  if (fun->has_nonlocal_label)
+    {
+      reason = G_("function %q+F can never be copied "
+		  "because it receives a non-local goto");
+      goto fail;
+    }
+
+  for (step = fun->local_decls; step; step = TREE_CHAIN (step))
+    {
+      tree decl = TREE_VALUE (step);
+
+      if (TREE_CODE (decl) == VAR_DECL
+	  && TREE_STATIC (decl)
+	  && !DECL_EXTERNAL (decl)
+	  && DECL_INITIAL (decl)
+	  && walk_tree_without_duplicates (&DECL_INITIAL (decl),
+					   has_label_address_in_static_1,
+					   fndecl))
+	{
+	  reason = G_("function %q+F can never be copied because it saves "
+		      "address of local label in a static variable");
+	  goto fail;
+	}
+
+      if (!TREE_STATIC (decl) && !DECL_EXTERNAL (decl)
+	  && variably_modified_type_p (TREE_TYPE (decl), NULL)
+	  && walk_tree_without_duplicates (&TREE_TYPE (decl),
+					   cannot_copy_type_1, NULL))
+	{
+	  reason = G_("function %q+F can never be copied "
+		      "because it uses variable sized variables");
+	  goto fail;
+	}
+    }
+
+ fail:
+  fun->cannot_be_copied_reason = reason;
+  fun->cannot_be_copied_set = true;
+  return reason;
+}
+
+
+static const char *inline_forbidden_reason;
+
+/* A callback for walk_gimple_seq to handle statements.  Returns non-null
+   iff a function can not be inlined.  Also sets the reason why. */
 
 static tree
 inline_forbidden_p_stmt (gimple_stmt_iterator *gsi, bool *handled_ops_p,
@@ -2597,21 +2659,6 @@ inline_forbidden_p_stmt (gimple_stmt_iterator *gsi, bool *handled_ops_p,
 	}
       break;
 
-    case GIMPLE_LABEL:
-      t = gimple_label_label (stmt);
-      if (DECL_NONLOCAL (t))
-	{
-	  /* We cannot inline a function that receives a non-local goto
-	     because we cannot remap the destination label used in the
-	     function that is performing the non-local goto.  */
-	  inline_forbidden_reason
-	    = G_("function %q+F can never be inlined "
-		 "because it receives a non-local goto");
-	  *handled_ops_p = true;
-	  return t;
-	}
-      break;
-
     default:
       break;
     }
@@ -2620,28 +2667,6 @@ inline_forbidden_p_stmt (gimple_stmt_iterator *gsi, bool *handled_ops_p,
   return NULL_TREE;
 }
 
-
-static tree
-inline_forbidden_p_2 (tree *nodep, int *walk_subtrees,
-		      void *fnp)
-{
-  tree node = *nodep;
-  tree fn = (tree) fnp;
-
-  if (TREE_CODE (node) == LABEL_DECL && DECL_CONTEXT (node) == fn)
-    {
-      inline_forbidden_reason
-	= G_("function %q+F can never be inlined "
-	     "because it saves address of local label in a static variable");
-      return node;
-    }
-
-  if (TYPE_P (node))
-    *walk_subtrees = 0;
-
-  return NULL_TREE;
-}
-
 /* Return true if FNDECL is a function that cannot be inlined into
    another one.  */
 
@@ -2649,12 +2674,18 @@ static bool
 inline_forbidden_p (tree fndecl)
 {
   struct function *fun = DECL_STRUCT_FUNCTION (fndecl);
-  tree step;
   struct walk_stmt_info wi;
   struct pointer_set_t *visited_nodes;
   basic_block bb;
   bool forbidden_p = false;
 
+  /* First check for shared reasons not to copy the code.  */
+  inline_forbidden_reason = copy_forbidden (fun, fndecl);
+  if (inline_forbidden_reason != NULL)
+    return true;
+
+  /* Next, walk the statements of the function looking for
+     constraucts we can't handle, or are non-optimal for inlining.  */
   visited_nodes = pointer_set_create ();
   memset (&wi, 0, sizeof (wi));
   wi.info = (void *) fndecl;
@@ -2664,31 +2695,12 @@ inline_forbidden_p (tree fndecl)
     {
       gimple ret;
       gimple_seq seq = bb_seq (bb);
-      ret = walk_gimple_seq (seq, inline_forbidden_p_stmt,
-			     inline_forbidden_p_op, &wi);
+      ret = walk_gimple_seq (seq, inline_forbidden_p_stmt, NULL, &wi);
       forbidden_p = (ret != NULL);
       if (forbidden_p)
-	goto egress;
-    }
-
-  for (step = fun->local_decls; step; step = TREE_CHAIN (step))
-    {
-      tree decl = TREE_VALUE (step);
-      if (TREE_CODE (decl) == VAR_DECL
-	  && TREE_STATIC (decl)
-	  && !DECL_EXTERNAL (decl)
-	  && DECL_INITIAL (decl))
-        {
-	  tree ret;
-	  ret = walk_tree_without_duplicates (&DECL_INITIAL (decl),
-					      inline_forbidden_p_2, fndecl);
-	  forbidden_p = (ret != NULL);
-	  if (forbidden_p)
-	    goto egress;
-        }
+	break;
     }
 
-egress:
   pointer_set_destroy (visited_nodes);
   return forbidden_p;
 }
@@ -2696,8 +2708,8 @@ egress:
 /* Returns nonzero if FN is a function that does not have any
    fundamental inline blocking properties.  */
 
-static bool
-inlinable_function_p (tree fn)
+bool
+tree_inlinable_function_p (tree fn)
 {
   bool inlinable = true;
   bool do_warning;
@@ -4304,17 +4316,11 @@ copy_static_chain (tree static_chain, copy_body_data * id)
 
 /* Return true if the function is allowed to be versioned.
    This is a guard for the versioning functionality.  */
+
 bool
 tree_versionable_function_p (tree fndecl)
 {
-  if (fndecl == NULL_TREE)
-    return false;
-  /* ??? There are cases where a function is
-     uninlinable but can be versioned.  */
-  if (!tree_inlinable_function_p (fndecl))
-    return false;
-  
-  return true;
+  return copy_forbidden (DECL_STRUCT_FUNCTION (fndecl), fndecl) == NULL;
 }
 
 /* Delete all unreachable basic blocks and update callgraph.
@@ -4420,7 +4426,8 @@ delete_unreachable_blocks_update_callgraph (copy_body_data *id)
    trees. If UPDATE_CLONES is set, the call_stmt fields
    of edges of clones of the function will be updated.  */
 void
-tree_function_versioning (tree old_decl, tree new_decl, VEC(ipa_replace_map_p,gc)* tree_map,
+tree_function_versioning (tree old_decl, tree new_decl,
+			  VEC(ipa_replace_map_p,gc)* tree_map,
 			  bool update_clones, bitmap args_to_skip)
 {
   struct cgraph_node *old_version_node;
@@ -4547,7 +4554,8 @@ tree_function_versioning (tree old_decl, tree new_decl, VEC(ipa_replace_map_p,gc
       }
   
   /* Copy the Function's body.  */
-  copy_body (&id, old_entry_block->count, old_entry_block->frequency, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR);
+  copy_body (&id, old_entry_block->count, old_entry_block->frequency,
+	     ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR);
   
   if (DECL_RESULT (old_decl) != NULL_TREE)
     {
@@ -4566,6 +4574,16 @@ tree_function_versioning (tree old_decl, tree new_decl, VEC(ipa_replace_map_p,gc
 	insert_init_stmt (bb, VEC_pop (gimple, init_stmts));
     }
 
+  /* Remap the nonlocal_goto_save_area, if any.  */
+  if (cfun->nonlocal_goto_save_area)
+    {
+      struct walk_stmt_info wi;
+
+      memset (&wi, 0, sizeof (wi));
+      wi.info = &id;
+      walk_tree (&cfun->nonlocal_goto_save_area, remap_gimple_op_r, &wi, NULL);
+    }
+
   /* Clean up.  */
   pointer_map_destroy (id.decl_map);
   free_dominance_info (CDI_DOMINATORS);