TBAA: make sure zero-length bitfield works for tbaa.struct and path-aware tbaa

For ms structs, zero-length bitfields following non-bitfield members are
completely ignored, we should not increase the field index.
Before the fix, we will have an assertion failure.

llvm-svn: 180038

1 files changed, 34 insertions, 0 deletions

diff --git a/clang/test/CodeGen/tbaa.cpp b/clang/test/CodeGen/tbaa.cpp
index c256b4af809..439fd20086e 100644
--- a/clang/test/CodeGen/tbaa.cpp
+++ b/clang/test/CodeGen/tbaa.cpp
@@ -192,6 +192,36 @@ uint32_t g12(StructC *C, StructD *D, uint64_t count) {
   return b1->a.f32;
 }
 
+// Make sure that zero-length bitfield works.
+#define ATTR __attribute__ ((ms_struct))
+struct five {
+  char a;
+  int :0;        /* ignored; prior field is not a bitfield. */
+  char b;
+  char c;
+} ATTR;
+char g13(struct five *a, struct five *b) {
+  return a->b;
+// CHECK: define signext i8 @{{.*}}(
+// CHECK: load i8* %{{.*}}, align 1, !tbaa !1
+// PATH: define signext i8 @{{.*}}(
+// PATH: load i8* %{{.*}}, align 1, !tbaa [[TAG_five_b:!.*]]
+}
+
+struct six {
+  char a;
+  int :0;
+  char b;
+  char c;
+};
+char g14(struct six *a, struct six *b) {
+// CHECK: define signext i8 @{{.*}}(
+// CHECK: load i8* %{{.*}}, align 1, !tbaa !1
+// PATH: define signext i8 @{{.*}}(
+// PATH: load i8* %{{.*}}, align 1, !tbaa [[TAG_six_b:!.*]]
+  return a->b;
+}
+
 // CHECK: !1 = metadata !{metadata !"omnipotent char", metadata !2}
 // CHECK: !2 = metadata !{metadata !"Simple C/C++ TBAA"}
 // CHECK: !4 = metadata !{metadata !"int", metadata !1}
@@ -219,3 +249,7 @@ uint32_t g12(StructC *C, StructD *D, uint64_t count) {
 // PATH: [[TYPE_C]] = metadata !{metadata !"_ZTS7StructC", i64 0, metadata [[TYPE_SHORT]], i64 4, metadata [[TYPE_B]], i64 28, metadata [[TYPE_INT]]}
 // PATH: [[TAG_D_b_a_f32]] = metadata !{metadata [[TYPE_D:!.*]], metadata [[TYPE_INT]], i64 12}
 // PATH: [[TYPE_D]] = metadata !{metadata !"_ZTS7StructD", i64 0, metadata [[TYPE_SHORT]], i64 4, metadata [[TYPE_B]], i64 28, metadata [[TYPE_INT]], i64 32, metadata [[TYPE_CHAR]]}
+// PATH: [[TAG_five_b]] = metadata !{metadata [[TYPE_five:!.*]], metadata [[TYPE_CHAR]], i64 1}
+// PATH: [[TYPE_five]] = metadata !{metadata !"_ZTS4five", i64 0, metadata [[TYPE_CHAR]], i64 1, metadata [[TYPE_CHAR]], i64 2, metadata [[TYPE_CHAR]]}
+// PATH: [[TAG_six_b]] = metadata !{metadata [[TYPE_six:!.*]], metadata [[TYPE_CHAR]], i64 4}
+// PATH: [[TYPE_six]] = metadata !{metadata !"_ZTS3six", i64 0, metadata [[TYPE_CHAR]], i64 4, metadata [[TYPE_INT]], i64 4, metadata [[TYPE_CHAR]], i64 5, metadata [[TYPE_CHAR]]}