[TargetLibraryInfo] Teach isValidProtoForLibFunc about tan

We would fail to validate the type of the tan function which would cause
downstream users of isValidProtoForLibFunc to assert.

This fixes PR28143.

llvm-svn: 272802
diff --git a/llvm/lib/Analysis/TargetLibraryInfo.cpp b/llvm/lib/Analysis/TargetLibraryInfo.cpp
index 789b039..f70b438 100644
--- a/llvm/lib/Analysis/TargetLibraryInfo.cpp
+++ b/llvm/lib/Analysis/TargetLibraryInfo.cpp
@@ -897,6 +897,9 @@
   case LibFunc::cos:
   case LibFunc::cosf:
   case LibFunc::cosl:
+  case LibFunc::tan:
+  case LibFunc::tanf:
+  case LibFunc::tanl:
   case LibFunc::exp:
   case LibFunc::expf:
   case LibFunc::expl: