Don't emit memcpy for copying fields of arrays of volatile elements.

Use the the path that generates a loop. This fixes
bogus error that clang puts out. // rdar://9894548



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@137080 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 43 insertions, 0 deletions

diff --git a/test/CodeGenCXX/copy-assign-volatile-synthesis.cpp b/test/CodeGenCXX/copy-assign-volatile-synthesis.cpp
new file mode 100644
index 0000000000..eb13503fdc
--- /dev/null
+++ b/test/CodeGenCXX/copy-assign-volatile-synthesis.cpp
@@ -0,0 +1,43 @@
+// RUN: %clang_cc1 -emit-llvm %s -o - | FileCheck %s
+// rdar://9894548
+
+typedef unsigned long word_t;
+typedef unsigned long u64_t;
+typedef unsigned int u32_t;
+
+class ioapic_redir_t {
+public:
+ union {
+  struct {
+   word_t vector : 8;
+
+   word_t delivery_mode : 3;
+   word_t dest_mode : 1;
+
+   word_t delivery_status : 1;
+   word_t polarity : 1;
+   word_t irr : 1;
+   word_t trigger_mode : 1;
+
+   word_t mask : 1;
+   word_t _pad0 : 15;
+
+   word_t dest : 8;
+  };
+  volatile u32_t raw[2];
+  volatile u64_t raw64;
+ };
+};
+
+struct ioapic_shadow_struct
+{
+ ioapic_redir_t redirs[24];
+} ioapic_shadow[16];
+
+void init_ioapic(unsigned long ioapic_id)
+{
+     ioapic_redir_t entry;
+     ioapic_shadow[ioapic_id].redirs[3] = entry;
+}
+
+// CHECK: call void @llvm.memcpy