[msan] Fix MsanTest to pass in track_origins=2 mode.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@230639 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 7 insertions, 0 deletions

diff --git a/lib/msan/msan.cc b/lib/msan/msan.cc
index ed6efbdd6..caa77366c 100644
--- a/lib/msan/msan.cc
+++ b/lib/msan/msan.cc
@@ -543,6 +543,13 @@ u32 __msan_get_origin(const void *a) {
   return *(u32*)origin_ptr;
 }
 
+int __msan_origin_is_descendant_or_same(u32 this_id, u32 prev_id) {
+  Origin o = Origin::FromRawId(this_id);
+  while (o.raw_id() != prev_id && o.isChainedOrigin())
+    o = o.getNextChainedOrigin(nullptr);
+  return o.raw_id() == prev_id;
+}
+
 u32 __msan_get_umr_origin() {
   return __msan_origin_tls;
 }