[AMDGPU][MC] Fix 2 for sanitizer failure in 364645

llvm-svn: 364656
diff --git a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
index 98044c9..366290d 100644
--- a/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
+++ b/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
@@ -810,9 +810,9 @@
   StreamId = (Val & STREAM_ID_MASK_) >> STREAM_ID_SHIFT_;
 }
 
-int64_t encodeMsg(int64_t MsgId,
-                  int64_t OpId,
-                  int64_t StreamId) {
+uint64_t encodeMsg(uint64_t MsgId,
+                   uint64_t OpId,
+                   uint64_t StreamId) {
   return (MsgId << ID_SHIFT_) |
          (OpId << OP_SHIFT_) |
          (StreamId << STREAM_ID_SHIFT_);