[Builtins] Treat `bcmp` as a builtin.

Summary:
This makes it consistent with `memcmp` and `__builtin_bcmp`.

Also see the discussion in https://reviews.llvm.org/D56593.

Reviewers: jyknight

Subscribers: kristina, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D58120

llvm-svn: 354023
diff --git a/clang/lib/AST/Decl.cpp b/clang/lib/AST/Decl.cpp
index 9896246..4f49bd7 100644
--- a/clang/lib/AST/Decl.cpp
+++ b/clang/lib/AST/Decl.cpp
@@ -3672,6 +3672,10 @@
   case Builtin::BImemcmp:
     return Builtin::BImemcmp;
 
+  case Builtin::BI__builtin_bcmp:
+  case Builtin::BIbcmp:
+    return Builtin::BIbcmp;
+
   case Builtin::BI__builtin_strncpy:
   case Builtin::BI__builtin___strncpy_chk:
   case Builtin::BIstrncpy:
@@ -3712,6 +3716,8 @@
         return Builtin::BImemmove;
       else if (FnInfo->isStr("memcmp"))
         return Builtin::BImemcmp;
+      else if (FnInfo->isStr("bcmp"))
+        return Builtin::BIbcmp;
       else if (FnInfo->isStr("strncpy"))
         return Builtin::BIstrncpy;
       else if (FnInfo->isStr("strncmp"))