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[PATCH] Fix small vtable verification bugs.
- From: Caroline Tice <cmtice at google dot com>
- To: GCC Patches <gcc-patches at gcc dot gnu dot org>
- Date: Fri, 6 Dec 2013 11:30:10 -0800
- Subject: [PATCH] Fix small vtable verification bugs.
- Authentication-results: sourceware.org; auth=none
The attached patch fixes two small problems with the current vtable
verification code: it makes the libvtv function decls globally
visible, and it updates all uses of the verified vtable pointer with
the verification results, rather than just the first use.
I have bootstrapped the compiler with this patch, both with and
without vtable verification enabled, and have run the regression
testsuites, both with and without vtable verification enabled, with no
regressions. I have only tested this on Linux.
Is this patch OK to commit?
-- Caroline Tice
cmtice@google.com
gcc ChangeLog:
2013-12-06 Caroline Tice <cmtice@google.com>
Submitting patch from Stephen Checkoway, s@cs.jhu.edu
* vtable-class-hierarchy.c (init_functions): Make the libvtv
function decls externally visible.
gcc/cp ChangeLog:
2013-12-06 Caroline Tice <cmtice@google.com>
Submitting patch from Stephen Checkoway, s@cs.jhu.edu
* vtable-class-hierarchy.c (init_functions): Make the libvtv
function decls externally visible.
Index: gcc/cp/vtable-class-hierarchy.c
===================================================================
--- gcc/cp/vtable-class-hierarchy.c (revision 205756)
+++ gcc/cp/vtable-class-hierarchy.c (working copy)
@@ -258,6 +258,7 @@ init_functions (void)
DECL_ATTRIBUTES (vlt_register_set_fndecl) =
tree_cons (get_identifier ("leaf"), NULL,
DECL_ATTRIBUTES (vlt_register_set_fndecl));
+ DECL_EXTERNAL(vlt_register_set_fndecl) = 1;
TREE_PUBLIC (vlt_register_set_fndecl) = 1;
DECL_PRESERVE_P (vlt_register_set_fndecl) = 1;
SET_DECL_LANGUAGE (vlt_register_set_fndecl, lang_cplusplus);
@@ -301,6 +302,7 @@ init_functions (void)
DECL_ATTRIBUTES (vlt_register_pairs_fndecl) =
tree_cons (get_identifier ("leaf"), NULL,
DECL_ATTRIBUTES (vlt_register_pairs_fndecl));
+ DECL_EXTERNAL(vlt_register_pairs_fndecl) = 1;
TREE_PUBLIC (vlt_register_pairs_fndecl) = 1;
DECL_PRESERVE_P (vlt_register_pairs_fndecl) = 1;
SET_DECL_LANGUAGE (vlt_register_pairs_fndecl, lang_cplusplus);
Index: gcc/vtable-verify.c
===================================================================
--- gcc/vtable-verify.c (revision 205756)
+++ gcc/vtable-verify.c (working copy)
@@ -646,9 +646,6 @@ verify_bb_vtables (basic_block bb)
if (vtable_map_node && vtable_map_node->vtbl_map_decl)
{
- use_operand_p use_p;
- ssa_op_iter iter;
-
vtable_map_node->is_used = true;
vtbl_var_decl = vtable_map_node->vtbl_map_decl;
@@ -695,35 +692,27 @@ verify_bb_vtables (basic_block bb)
gimple_call_set_lhs (call_stmt, tmp0);
update_stmt (call_stmt);
- /* Find the next stmt, after the vptr assignment
- statememt, which should use the result of the
- vptr assignment statement value. */
- gsi_next (&gsi_vtbl_assign);
- gimple next_stmt = gsi_stmt (gsi_vtbl_assign);
-
- if (!next_stmt)
- return;
-
- /* Find any/all uses of 'lhs' in next_stmt, and
- replace them with 'tmp0'. */
+ /* Replace all uses of lhs with tmp0. */
found = false;
- FOR_EACH_PHI_OR_STMT_USE (use_p, next_stmt, iter,
- SSA_OP_ALL_USES)
+ imm_use_iterator iterator;
+ gimple use_stmt;
+ FOR_EACH_IMM_USE_STMT (use_stmt, iterator, lhs)
{
- tree op = USE_FROM_PTR (use_p);
- if (op == lhs)
- {
- SET_USE (use_p, tmp0);
- found = true;
- }
+ use_operand_p use_p;
+ if (use_stmt == call_stmt)
+ continue;
+ FOR_EACH_IMM_USE_ON_STMT (use_p, iterator)
+ SET_USE (use_p, tmp0);
+ update_stmt (use_stmt);
+ found = true;
}
- update_stmt (next_stmt);
+
gcc_assert (found);
/* Insert the new verification call just after the
statement that gets the vtable pointer out of the
object. */
- gsi_vtbl_assign = gsi_for_stmt (stmt);
+ gcc_assert (gsi_stmt (gsi_vtbl_assign) == stmt);
gsi_insert_after (&gsi_vtbl_assign, call_stmt,
GSI_NEW_STMT);