Fix PR85782: C++ ICE with continue statements inside acc loops

[Cesar Philippidis]

This patch resolves the issue in PR85782, which involves a C++ ICE
caused by OpenACC loops which contain continue statements. The problem
is that genericize_continue_stmt expects a continue label for the loop,
but that wasn't getting set up acc loops. This patch fixes that by
calling genericize_omp_for_stmt for OACC_LOOP statements, because
OACC_LOOP and OMP_FOR statements are almost identical at this point of
parsing.

I regression tested it on x86_64-linux with nvptx offloading.

Is this ok for trunk and the stable branches?  The patch for the stable
branches is slightly different, because cp_genericize_r uses if
statements to check for statement types instead of a huge switch statement.

Cesar

2018-05-15  Cesar Philippidis  <ce...@codesourcery.com>

	PR c++/85782

	gcc/cp/
	* cp-gimplify.c (cp_genericize_r): Call genericize_omp_for_stmt for
	OACC_LOOPs.

	gcc/testsuite/
	* c-c++-common/goacc/pr85782.c: New test.

	libgomp/
	* testsuite/libgomp.oacc-c-c++-common/pr85782.c: New test.


diff --git a/gcc/cp/cp-gimplify.c b/gcc/cp/cp-gimplify.c
index eda5f05..55aef86 100644
--- a/gcc/cp/cp-gimplify.c
+++ b/gcc/cp/cp-gimplify.c
@@ -1463,6 +1463,7 @@ cp_genericize_r (tree *stmt_p, int *walk_subtrees, void *data)
     case OMP_FOR:
     case OMP_SIMD:
     case OMP_DISTRIBUTE:
+    case OACC_LOOP:
       genericize_omp_for_stmt (stmt_p, walk_subtrees, data);
       break;
 
diff --git a/gcc/testsuite/c-c++-common/goacc/pr85782.c b/gcc/testsuite/c-c++-common/goacc/pr85782.c
new file mode 100644
index 0000000..f213a24
--- /dev/null
+++ b/gcc/testsuite/c-c++-common/goacc/pr85782.c
@@ -0,0 +1,11 @@
+/* PR c++/85782 */
+
+void
+foo ()
+{
+  int i;
+  
+  #pragma acc parallel loop
+  for (i = 0; i < 100; i++)
+    continue;
+}
diff --git a/libgomp/testsuite/libgomp.oacc-c-c++-common/pr85782.c b/libgomp/testsuite/libgomp.oacc-c-c++-common/pr85782.c
new file mode 100644
index 0000000..6f84dfc
--- /dev/null
+++ b/libgomp/testsuite/libgomp.oacc-c-c++-common/pr85782.c
@@ -0,0 +1,32 @@
+/* PR c++/85782 */
+
+#include <assert.h>
+
+#define N 100
+
+int
+main ()
+{
+  int i, a[N];
+
+  for (i = 0; i < N; i++)
+    a[i] = i+1;
+
+  #pragma acc parallel loop copy(a)
+  for (i = 0; i < N; i++)
+    {
+      if (i % 2)
+	continue;
+      a[i] = 0;
+    }
+
+  for (i = 0; i < N; i++)
+    {
+      if (i % 2)
+	assert (a[i] == i+1);
+      else
+	assert (a[i] == 0);
+    }
+
+    return 0;
+}