[CHKP] Support returned bounds in thunks expand

[Ilya Enkovich]

Hi,

Currentl we loose returned bounds when functions are merged.  This patch fixes 
it by adding returne bounds support for cgraph_node::expand_thunk.  
Bootstrapped and tested on x86_64-unknown-linux-gnu.  OK for trunk?

Thanks,
Ilya
--
gcc/

2015-03-06  Ilya Enkovich  <ilya.enkov...@intel.com>

        * cgraphunit.c (cgraph_node::expand_thunk): Build returned
        bounds for instrumented functions.

gcc/testsuite/

2015-03-06  Ilya Enkovich  <ilya.enkov...@intel.com>

        * gcc/testsuite/gcc.target/i386/thunk-retbnd.c: New.


diff --git a/gcc/cgraphunit.c b/gcc/cgraphunit.c
index e640907..fc38e67 100644
--- a/gcc/cgraphunit.c
+++ b/gcc/cgraphunit.c
@@ -1581,6 +1581,7 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool 
force_gimple_thunk)
       int i;
       tree resdecl;
       tree restmp = NULL;
+      tree resbnd = NULL;
 
       gcall *call;
       greturn *ret;
@@ -1697,6 +1698,21 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool 
force_gimple_thunk)
       gsi_insert_after (&bsi, call, GSI_NEW_STMT);
       if (!alias_is_noreturn)
        {
+         if (instrumentation_clone
+             && !DECL_BY_REFERENCE (resdecl)
+             && restmp
+             && BOUNDED_P (restmp))
+           {
+             tree fn = targetm.builtin_chkp_function (BUILT_IN_CHKP_BNDRET);
+             gcall *retbnd = gimple_build_call (fn, 1, restmp);
+
+             resbnd = create_tmp_reg (pointer_bounds_type_node, "retbnd");
+             gimple_call_set_lhs (retbnd, resbnd);
+
+             gsi_insert_after (&bsi, retbnd, GSI_NEW_STMT);
+             create_edge (get_create (fn), retbnd, callees->count, 
callees->frequency);
+           }
+
          if (restmp && !this_adjusting
              && (fixed_offset || virtual_offset))
            {
@@ -1766,6 +1782,7 @@ cgraph_node::expand_thunk (bool output_asm_thunks, bool 
force_gimple_thunk)
            ret = gimple_build_return (restmp);
          else
            ret = gimple_build_return (resdecl);
+         gimple_return_set_retbnd (ret, resbnd);
 
          gsi_insert_after (&bsi, ret, GSI_NEW_STMT);
        }
diff --git a/gcc/testsuite/gcc.target/i386/thunk-retbnd.c 
b/gcc/testsuite/gcc.target/i386/thunk-retbnd.c
new file mode 100644
index 0000000..d9bd031
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/thunk-retbnd.c
@@ -0,0 +1,19 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target mpx } */
+/* { dg-options "-O2 -fcheck-pointer-bounds -mmpx -fdump-tree-optimized" } */
+/* { dg-final { scan-tree-dump-times "return &glob," 2 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+
+int glob;
+
+int *
+test1 (void)
+{
+  return &glob;
+}
+
+int *
+test2 (void)
+{
+  return test1 ();
+}