re PR middle-end/88968 (Stack overflow in gimplify_expr)

	PR middle-end/88968
	* gimplify.c (gimplify_omp_atomic): Handle bitfield atomics with
	non-integral DECL_BIT_FIELD_REPRESENTATIVEs.

	* c-omp.c (c_finish_omp_atomic): For bitfield atomics, update type
	variable after using BIT_FIELD_REF.

	* c-c++-common/gomp/atomic-23.c: New test.

From-SVN: r268165

6 files changed, 97 insertions, 5 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 548ccda..86ebc0f 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,9 @@
 2019-01-22  Jakub Jelinek  <jakub@redhat.com>
 
+	PR middle-end/88968
+	* gimplify.c (gimplify_omp_atomic): Handle bitfield atomics with
+	non-integral DECL_BIT_FIELD_REPRESENTATIVEs.
+
 	PR target/87064
 	* config/rs6000/vsx.md (*vsx_reduc_<VEC_reduc_name>_v2df_scalar):
 	Disable for little endian.
diff --git a/gcc/c-family/ChangeLog b/gcc/c-family/ChangeLog
index 4aaf819..86efe27 100644
--- a/gcc/c-family/ChangeLog
+++ b/gcc/c-family/ChangeLog
@@ -1,3 +1,9 @@
+2019-01-22  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/88968
+	* c-omp.c (c_finish_omp_atomic): For bitfield atomics, update type
+	variable after using BIT_FIELD_REF.
+
 2019-01-18  H.J. Lu  <hongjiu.lu@intel.com>
 
 	PR c/51628
diff --git a/gcc/c-family/c-omp.c b/gcc/c-family/c-omp.c
index 11aeeb0..16e7198 100644
--- a/gcc/c-family/c-omp.c
+++ b/gcc/c-family/c-omp.c
@@ -378,8 +378,11 @@ c_finish_omp_atomic (location_t loc, enum tree_code code,
 	    }
 	}
       if (blhs)
-	x = build3_loc (loc, BIT_FIELD_REF, TREE_TYPE (blhs), x,
-			bitsize_int (bitsize), bitsize_int (bitpos));
+	{
+	  x = build3_loc (loc, BIT_FIELD_REF, TREE_TYPE (blhs), x,
+			  bitsize_int (bitsize), bitsize_int (bitpos));
+	  type = TREE_TYPE (blhs);
+	}
       x = build_modify_expr (loc, v, NULL_TREE, NOP_EXPR,
 			     loc, x, NULL_TREE);
       if (rhs1 && rhs1 != orig_lhs)
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 5677ddd..5916678 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -11969,9 +11969,36 @@ gimplify_omp_atomic (tree *expr_p, gimple_seq *pre_p)
   loadstmt = gimple_build_omp_atomic_load (tmp_load, addr,
 					   OMP_ATOMIC_MEMORY_ORDER (*expr_p));
   gimplify_seq_add_stmt (pre_p, loadstmt);
-  if (rhs && gimplify_expr (&rhs, pre_p, NULL, is_gimple_val, fb_rvalue)
-      != GS_ALL_DONE)
-    return GS_ERROR;
+  if (rhs)
+    {
+      /* BIT_INSERT_EXPR is not valid for non-integral bitfield
+	 representatives.  Use BIT_FIELD_REF on the lhs instead.  */
+      if (TREE_CODE (rhs) == BIT_INSERT_EXPR
+	  && !INTEGRAL_TYPE_P (TREE_TYPE (tmp_load)))
+	{
+	  tree bitpos = TREE_OPERAND (rhs, 2);
+	  tree op1 = TREE_OPERAND (rhs, 1);
+	  tree bitsize;
+	  tree tmp_store = tmp_load;
+	  if (TREE_CODE (*expr_p) == OMP_ATOMIC_CAPTURE_OLD)
+	    tmp_store = get_initialized_tmp_var (tmp_load, pre_p, NULL);
+	  if (INTEGRAL_TYPE_P (TREE_TYPE (op1)))
+	    bitsize = bitsize_int (TYPE_PRECISION (TREE_TYPE (op1)));
+	  else
+	    bitsize = TYPE_SIZE (TREE_TYPE (op1));
+	  gcc_assert (TREE_OPERAND (rhs, 0) == tmp_load);
+	  tree t = build2_loc (EXPR_LOCATION (rhs),
+			       MODIFY_EXPR, void_type_node,
+			       build3_loc (EXPR_LOCATION (rhs), BIT_FIELD_REF,
+					   TREE_TYPE (op1), tmp_store, bitsize,
+					   bitpos), op1);
+	  gimplify_and_add (t, pre_p);
+	  rhs = tmp_store;
+	}
+      if (gimplify_expr (&rhs, pre_p, NULL, is_gimple_val, fb_rvalue)
+	  != GS_ALL_DONE)
+	return GS_ERROR;
+    }
 
   if (TREE_CODE (*expr_p) == OMP_ATOMIC_READ)
     rhs = tmp_load;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 66b692e..997b48e 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-01-22  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/88968
+	* c-c++-common/gomp/atomic-23.c: New test.
+
 2019-01-22  Harald Anlauf  <anlauf@gmx.de>
 
 	PR fortran/88579
diff --git a/gcc/testsuite/c-c++-common/gomp/atomic-23.c b/gcc/testsuite/c-c++-common/gomp/atomic-23.c
new file mode 100644
index 0000000..969cbf9
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/gomp/atomic-23.c
@@ -0,0 +1,47 @@
+/* PR middle-end/88968 */
+/* { dg-do compile } */
+
+struct __attribute__((packed)) S {
+  unsigned int a : 16;
+  unsigned int b : 1;
+} s;
+
+void
+f1 (void)
+{
+#pragma omp atomic
+  ++s.a;
+}
+
+int
+f2 (void)
+{
+  int r;
+#pragma omp atomic capture
+  {
+    r = s.a;
+    s.a = 0;
+  }
+  return r;
+}
+
+int
+f3 (void)
+{
+  int r;
+#pragma omp atomic capture
+  {
+    r = s.a;
+    s.a = s.a + 32;
+  }
+  return r;
+}
+
+int
+f4 (void)
+{
+  int r;
+#pragma omp atomic capture
+  r = s.a = s.a + 32;
+  return r;
+}