re PR middle-end/42898 (volatile structures and compound literal initializers)

2010-01-31  Richard Guenther  <rguenther@suse.de>

	PR middle-end/42898
	* gimplify.c (gimplify_init_constructor): For volatile LHS
	initialize a temporary.

	* gcc.dg/torture/pr42898.c: New testcase.

From-SVN: r156404

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b283f28fb388cfab9b7b11840a8ecc294556dab4..d91b75e9a2d40b623f28e63a2ef04bb5001ccec2 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2010-01-31  Richard Guenther  <rguenther@suse.de>
+
+       PR middle-end/42898
+       * gimplify.c (gimplify_init_constructor): For volatile LHS
+       initialize a temporary.
+
 2010-01-31  Matthias Klose  <doko@ubuntu.com>
 
        * configure.ac: Fix __stack_chk_fail check for cross builds configured

diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index ccae4d89a7279074f6cc19cae6f7c6f8bbe31d52..fac3fdaa223615f8509b72a774607873351fd260 100644 (file)
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -3745,6 +3745,21 @@ gimplify_init_constructor (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
              }
          }
 
+       /* If the target is volatile and we have non-zero elements
+          initialize the target from a temporary.  */
+       if (TREE_THIS_VOLATILE (object)
+           && !TREE_ADDRESSABLE (type)
+           && num_nonzero_elements > 0)
+         {
+           tree temp = create_tmp_var (TYPE_MAIN_VARIANT (type), NULL);
+           TREE_OPERAND (*expr_p, 0) = temp;
+           *expr_p = build2 (COMPOUND_EXPR, TREE_TYPE (*expr_p),
+                             *expr_p,
+                             build2 (MODIFY_EXPR, void_type_node,
+                                     object, temp));
+           return GS_OK;
+         }
+
        if (notify_temp_creation)
          return GS_OK;
 

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8257646e9a5b0d357f885e6a2543b8d870cc62bf..23730795d5d4c104ae9030628154a1330a8f7de4 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-01-31  Richard Guenther  <rguenther@suse.de>
+
+       PR middle-end/42898
+       * gcc.dg/torture/pr42898.c: New testcase.
+
 2010-01-31  Paul Thomas  <pault@gcc.gnu.org>
 
         PR fortran/38324

diff --git a/gcc/testsuite/gcc.dg/torture/pr42898.c b/gcc/testsuite/gcc.dg/torture/pr42898.c
new file mode 100644 (file)
index 0000000..df8b46a
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/torture/pr42898.c
@@ -0,0 +1,23 @@
+/* { dg-do compile } */
+/* { dg-options "-fdump-tree-optimized" } */
+
+struct hardware {
+  int parm1:8;
+  int :4;
+  int parm2:4;
+  int parm3:15;
+  int parm4:1;
+};
+
+void f1(volatile struct hardware *ptr)
+{
+  *ptr=(struct hardware) {
+    .parm1=42,
+    .parm2=13,
+    .parm3=11850,
+    .parm4=1,
+  };
+}
+
+/* { dg-final { scan-tree-dump-times "\\*ptr" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */