1 files changed, 44 insertions, 0 deletions
diff --git a/clang/test/CodeGen/bitfield-assign.c b/clang/test/CodeGen/bitfield-assign.c
new file mode 100644
index 0000000..b8ab613
--- /dev/null
+++ b/clang/test/CodeGen/bitfield-assign.c
@@ -0,0 +1,44 @@
+/* Check that the result of a bitfield assignment is properly
+   truncated and does not generate a redundant load. */
+
+/* Check that we get one load for each simple assign and two for the
+   compound assign (load the old value before the add then load again
+   to store back). Also check that our g0 pattern is good. */
+// RUN: %clang_cc1 -triple i386-unknown-unknown -O0 -emit-llvm -o %t %s
+// RUN: grep 'load ' %t | count 5
+// RUN: grep "@g0" %t | count 4
+
+// Check that we got the right value.
+// RUN: %clang_cc1 -triple i386-unknown-unknown -O3 -emit-llvm -o %t %s
+// RUN: grep 'load ' %t | count 0
+// RUN: grep "@g0" %t | count 0
+
+struct s0 {
+  int f0 : 2;
+  _Bool f1 : 1;
+  unsigned f2 : 2;
+};
+
+int g0();
+
+void f0(void) {
+  struct s0 s;  
+  if ((s.f0 = 3) != -1) g0();
+}
+
+void f1(void) {
+  struct s0 s;  
+  if ((s.f1 = 3) != 1) g0();
+}
+
+void f2(void) {
+  struct s0 s;  
+  if ((s.f2 = 3) != 3) g0();
+}
+
+void f3(void) {
+  struct s0 s;
+  // Just check this one for load counts.
+  s.f0 += 3;
+}
+