PR middle-end/55750

	* gimplify.c (gimplify_self_mod_expr): Don't force lvalue to
	pass is_gimple_min_lval.

	* gcc.c-torture/execute/pr55750.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@194647 138bc75d-0d04-0410-961f-82ee72b054a4

4 files changed, 43 insertions, 13 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1fb596fb2c0..9e7a4b73f2e 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2012-12-20  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/55750
+	* gimplify.c (gimplify_self_mod_expr): Don't force lvalue to
+	pass is_gimple_min_lval.
+
 2012-12-20  Richard Henderson  <rth@redhat.com>
 	    Andreas Krebbel  <Andreas.Krebbel@de.ibm.com>
 
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index f628b8ab3c0..e79d06397e0 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -2391,25 +2391,15 @@ gimplify_self_mod_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p,
   rhs = TREE_OPERAND (*expr_p, 1);
 
   /* For postfix operator, we evaluate the LHS to an rvalue and then use
-     that as the result value and in the postqueue operation.  We also
-     make sure to make lvalue a minimal lval, see
-     gcc.c-torture/execute/20040313-1.c for an example where this matters.  */
+     that as the result value and in the postqueue operation.  */
   if (postfix)
     {
-      if (!is_gimple_min_lval (lvalue))
-	{
-	  mark_addressable (lvalue);
-	  lvalue = build_fold_addr_expr_loc (input_location, lvalue);
-	  gimplify_expr (&lvalue, pre_p, post_p, is_gimple_val, fb_rvalue);
-	  lvalue = build_fold_indirect_ref_loc (input_location, lvalue);
-	}
       ret = gimplify_expr (&lhs, pre_p, post_p, is_gimple_val, fb_rvalue);
       if (ret == GS_ERROR)
 	return ret;
-    }
 
-  if (postfix)
-    lhs = get_initialized_tmp_var (lhs, pre_p, NULL);
+      lhs = get_initialized_tmp_var (lhs, pre_p, NULL);
+    }
 
   /* For POINTERs increment, use POINTER_PLUS_EXPR.  */
   if (POINTER_TYPE_P (TREE_TYPE (lhs)))
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c7cb2336234..b89fa028ac6 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2012-12-20  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/55750
+	* gcc.c-torture/execute/pr55750.c: New test.
+
 2012-12-20  Richard Biener  <rguenther@suse.de>
 
 	PR middle-end/55740
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr55750.c b/gcc/testsuite/gcc.c-torture/execute/pr55750.c
new file mode 100644
index 00000000000..d2b3c63cd04
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr55750.c
@@ -0,0 +1,29 @@
+/* PR middle-end/55750 */
+
+extern void abort (void);
+
+struct S
+{
+  int m : 1;
+  int n : 7;
+} arr[2];
+
+__attribute__((noinline, noclone)) void
+foo (unsigned i)
+{
+  arr[i].n++;
+}
+
+int
+main ()
+{
+  arr[0].m = -1;
+  arr[0].n = (1 << 6) - 1;
+  arr[1].m = 0;
+  arr[1].n = -1;
+  foo (0);
+  foo (1);
+  if (arr[0].m != -1 || arr[0].n != -(1 << 6) || arr[1].m != 0 || arr[1].n != 0)
+    abort ();
+  return 0;
+}