xfail failing tests and link issues

Author: kmpeng

test/Feature/HLSLLib/dot2add.test

@@ -94,6 +94,13 @@ DescriptorSets:
         Binding: 3
 #--- end
 
+# https://github.com/llvm/llvm-project/issues/152585
+# XFAIL: Clang-DirectX
+# XFAIL: Clang-Metal
+
+# https://github.com/llvm/llvm-project/issues/149561
+# XFAIL: Clang-Vulkan
+
 # REQUIRES: Half
 # RUN: split-file %s %t
 # RUN: %dxc_target -enable-16bit-types -T cs_6_5 -Fo %t.o %t/source.hlsl