[PATCH 3/7] cgraph_node -> cgraph_get_node with asserts

[Martin Jambor <mjambor at suse dot cz>]

Hi,

the patch below changes a number of calls to cgraph_node to calls to
cgraph_get_node.  These calls should never return NULL but because the
callers do not immediately dereference the pointer they get, a NULL
value would result in a segmentation fault at some later point,
obscuring the real cause.  Therefore I have added checking asserts to
guard this does not happen.

Bootstrapped and tested separately on x86_64-linux without any
problems, tests on other platforms (together with the other patches)
in progress.

OK for trunk?

Thanks,

Martin


2011-04-06  Martin Jambor  <mjambor@suse.cz>

	* tree-inline.c (tree_function_versioning): Call cgraph_get_node
	instead of cgraph_node and assert it does not return NULL.
	* lto-streamer-in.c (lto_read_body): Likewise.
	* omp-low.c (new_omp_context): Likewise.
	(create_task_copyfn): Likewise.
	* tree-emutls.c (lower_emutls_function_body): Likewise.
	* matrix-reorg.c (transform_allocation_sites): Likewise.



Index: src/gcc/tree-inline.c
===================================================================
--- src.orig/gcc/tree-inline.c
+++ src/gcc/tree-inline.c
@@ -5001,8 +5001,10 @@ tree_function_versioning (tree old_decl,
 	      && TREE_CODE (new_decl) == FUNCTION_DECL);
   DECL_POSSIBLY_INLINED (old_decl) = 1;
 
-  old_version_node = cgraph_node (old_decl);
-  new_version_node = cgraph_node (new_decl);
+  old_version_node = cgraph_get_node (old_decl);
+  gcc_checking_assert (old_version_node);
+  new_version_node = cgraph_get_node (new_decl);
+  gcc_checking_assert (new_version_node);
 
   /* Output the inlining info for this abstract function, since it has been
      inlined.  If we don't do this now, we can lose the information about the
Index: src/gcc/lto-streamer-in.c
===================================================================
--- src.orig/gcc/lto-streamer-in.c
+++ src/gcc/lto-streamer-in.c
@@ -1446,8 +1446,9 @@ lto_read_body (struct lto_file_decl_data
     {
       struct function *fn = DECL_STRUCT_FUNCTION (fn_decl);
       struct lto_in_decl_state *decl_state;
-      struct cgraph_node *node = cgraph_node (fn_decl);
+      struct cgraph_node *node = cgraph_get_node (fn_decl);
 
+      gcc_checking_assert (node);
       push_cfun (fn);
       init_tree_ssa (fn);
 
Index: src/gcc/omp-low.c
===================================================================
--- src.orig/gcc/omp-low.c
+++ src/gcc/omp-low.c
@@ -1209,7 +1209,8 @@ new_omp_context (gimple stmt, omp_contex
     {
       ctx->cb.src_fn = current_function_decl;
       ctx->cb.dst_fn = current_function_decl;
-      ctx->cb.src_node = cgraph_node (current_function_decl);
+      ctx->cb.src_node = cgraph_get_node (current_function_decl);
+      gcc_checking_assert (ctx->cb.src_node);
       ctx->cb.dst_node = ctx->cb.src_node;
       ctx->cb.src_cfun = cfun;
       ctx->cb.copy_decl = omp_copy_decl;
@@ -6263,7 +6264,8 @@ create_task_copyfn (gimple task_stmt, om
       memset (&tcctx, '\0', sizeof (tcctx));
       tcctx.cb.src_fn = ctx->cb.src_fn;
       tcctx.cb.dst_fn = child_fn;
-      tcctx.cb.src_node = cgraph_node (tcctx.cb.src_fn);
+      tcctx.cb.src_node = cgraph_get_node (tcctx.cb.src_fn);
+      gcc_checking_assert (tcctx.cb.src_node);
       tcctx.cb.dst_node = tcctx.cb.src_node;
       tcctx.cb.src_cfun = ctx->cb.src_cfun;
       tcctx.cb.copy_decl = task_copyfn_copy_decl;
Index: src/gcc/tree-emutls.c
===================================================================
--- src.orig/gcc/tree-emutls.c
+++ src/gcc/tree-emutls.c
@@ -619,7 +619,8 @@ lower_emutls_function_body (struct cgrap
 
   d.cfun_node = node;
   d.builtin_decl = built_in_decls[BUILT_IN_EMUTLS_GET_ADDRESS];
-  d.builtin_node = cgraph_node (d.builtin_decl);
+  d.builtin_node = cgraph_get_node (d.builtin_decl);
+  gcc_checking_assert (d.builtin_node);
 
   FOR_EACH_BB (d.bb)
     {
Index: src/gcc/matrix-reorg.c
===================================================================
--- src.orig/gcc/matrix-reorg.c
+++ src/gcc/matrix-reorg.c
@@ -2169,7 +2169,8 @@ transform_allocation_sites (void **slot,
   update_ssa (TODO_update_ssa);
   /* Replace the malloc size argument in the malloc of level 0 to be
      the size of all the dimensions.  */
-  c_node = cgraph_node (mi->allocation_function_decl);
+  c_node = cgraph_get_node (mi->allocation_function_decl);
+  gcc_checking_assert (c_node);
   old_size_0 = gimple_call_arg (call_stmt_0, 0);
   tmp = force_gimple_operand_gsi (&gsi, mi->dimension_size[0], true,
 				  NULL, true, GSI_SAME_STMT);
@@ -2218,7 +2219,8 @@ transform_allocation_sites (void **slot,
       if (!mi->free_stmts[i].stmt)
 	continue;
 
-      c_node = cgraph_node (mi->free_stmts[i].func);
+      c_node = cgraph_get_node (mi->free_stmts[i].func);
+      gcc_checking_assert (c_node);
       gcc_assert (is_gimple_call (mi->free_stmts[i].stmt));
       e = cgraph_edge (c_node, mi->free_stmts[i].stmt);
       gcc_assert (e);