Diagnose volatile accesses in transaction_safe function.jason/tm

	* trans-mem.c (volatile_lvalue_p): Rename from volatile_var_p.
	(diagnose_tm_1_op): Also diagnose volatile accesses in
	transaction_safe function.

3 files changed, 31 insertions, 11 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8d55423390e..2505fa48d44 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2015-09-29  Jason Merrill  <jason@redhat.com>
+
+	* trans-mem.c (volatile_lvalue_p): Rename from volatile_var_p.
+	(diagnose_tm_1_op): Also diagnose volatile accesses in
+	transaction_safe function.
+
 2015-09-29  Jeff Law  <law@redhat.com>
 
 	* config/microblaze/microblaze.c (microblaze_version_to_int): Remove
diff --git a/gcc/testsuite/g++.dg/tm/unsafe1a.C b/gcc/testsuite/g++.dg/tm/unsafe1a.C
new file mode 100644
index 00000000000..f4d6eba22d9
--- /dev/null
+++ b/gcc/testsuite/g++.dg/tm/unsafe1a.C
@@ -0,0 +1,9 @@
+// Transaction-unsafe testcase from TM TS.
+// { dg-options -fgnu-tm }
+
+volatile int * p = 0;
+int f() transaction_safe {
+  int x = 0;	     // ok: not volatile
+  p = &x;	     // ok: the pointer is not volatile
+  int i = *p;	     // { dg-error "volatile" "read through volatile glvalue" }
+}
diff --git a/gcc/trans-mem.c b/gcc/trans-mem.c
index d9a681f2a34..a73d4bc5daa 100644
--- a/gcc/trans-mem.c
+++ b/gcc/trans-mem.c
@@ -594,12 +594,12 @@ struct diagnose_tm
   gimple *stmt;
 };
 
-/* Return true if T is a volatile variable of some kind.  */
+/* Return true if T is a volatile lvalue of some kind.  */
 
 static bool
-volatile_var_p (tree t)
+volatile_lvalue_p (tree t)
 {
-  return (SSA_VAR_P (t)
+  return ((SSA_VAR_P (t) || REFERENCE_CLASS_P (t))
 	  && TREE_THIS_VOLATILE (TREE_TYPE (t)));
 }
 
@@ -612,14 +612,19 @@ diagnose_tm_1_op (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
   struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
   struct diagnose_tm *d = (struct diagnose_tm *) wi->info;
 
-  if (volatile_var_p (*tp)
-      && d->block_flags & DIAG_TM_SAFE
-      && !d->saw_volatile)
+  if (TYPE_P (*tp))
+    *walk_subtrees = false;
+  else if (volatile_lvalue_p (*tp)
+	   && !d->saw_volatile)
     {
       d->saw_volatile = 1;
-      error_at (gimple_location (d->stmt),
-		"invalid volatile use of %qD inside transaction",
-		*tp);
+      if (d->block_flags & DIAG_TM_SAFE)
+	error_at (gimple_location (d->stmt),
+		  "invalid use of volatile lvalue inside transaction");
+      else if (d->func_flags & DIAG_TM_SAFE)
+	error_at (gimple_location (d->stmt),
+		  "invalid use of volatile lvalue inside %<transaction_safe%>"
+		  "function");
     }
 
   return NULL_TREE;
@@ -4300,7 +4305,7 @@ ipa_tm_scan_irr_block (basic_block bb)
 	    {
 	      tree lhs = gimple_assign_lhs (stmt);
 	      tree rhs = gimple_assign_rhs1 (stmt);
-	      if (volatile_var_p (lhs) || volatile_var_p (rhs))
+	      if (volatile_lvalue_p (lhs) || volatile_lvalue_p (rhs))
 		return true;
 	    }
 	  break;
@@ -4308,7 +4313,7 @@ ipa_tm_scan_irr_block (basic_block bb)
 	case GIMPLE_CALL:
 	  {
 	    tree lhs = gimple_call_lhs (stmt);
-	    if (lhs && volatile_var_p (lhs))
+	    if (lhs && volatile_lvalue_p (lhs))
 	      return true;
 
 	    if (is_tm_pure_call (stmt))