[OpenCL] Make TableGen'd builtin tables and helper functions static

[Pierre]

Hello Tom,
Thank you for adding me, the changes seem correct to me.
There is a new version of the tablegen builtin functions that makes these tables static/const. It still needs some work, so I thing it's relevant to make this change in the meantime :
https://reviews.llvm.org/D63434

[Anastasia]

LGTM! Thanks!

clang/lib/Sema/SemaLookup.cpp

 /// \param II  The identifier being resolved
 /// \param Index  The list of prototypes starts at Index in OpenCLBuiltins[]
 /// \param Len  The list of prototypes has Len elements
 static void InsertOCLBuiltinDeclarations(Sema &S, LookupResult &LR,
                                          IdentifierInfo *II, unsigned Index,
                                          unsigned Len) {
 
   for (unsigned i = 0; i < Len; ++i) {
-    OpenCLBuiltinDecl &Decl = OpenCLBuiltins[Index - 1 + i];
+    const OpenCLBuiltinDecl &Decl = OpenCLBuiltins[Index - 1 + i];
     ASTContext &Context = S.Context;
 
     // Ignore this BIF if the version is incorrect.
     if (Context.getLangOpts().OpenCLVersion < Decl.Version)
       continue;
 
     FunctionProtoType::ExtProtoInfo PI;
     PI.Variadic = false;

clang/utils/TableGen/ClangOpenCLBuiltinEmitter.cpp

for (const auto *B : Builtins) {
     } else {
       SignIndex = it->second;
     }
     OverloadInfo[BName].push_back(std::make_pair(B, SignIndex));
   }
 }
 
 void BuiltinNameEmitter::EmitSignatureTable() {
-  OS << "OpenCLType OpenCLSignature[] = {\n";
+  OS << "static const OpenCLType OpenCLSignature[] = {\n";
   for (auto &P : SignatureSet) {
     OS << "// " << P.second << "\n";
     for (Record *R : P.first) {
       OS << "{ OCLT_" << R->getValueAsString("Name") << ", "
          << R->getValueAsInt("VecWidth") << ", "
          << R->getValueAsString("AddrSpace") << ", "
          << R->getValueAsBit("IsPointer") << "},";
       OS << "\n";
     }
   }
   OS << "};\n\n";
 }
 
 void BuiltinNameEmitter::EmitBuiltinTable() {
-  OS << "OpenCLBuiltinDecl OpenCLBuiltins[] = {\n";
+  OS << "static const OpenCLBuiltinDecl OpenCLBuiltins[] = {\n";
   for (auto &i : OverloadInfo) {
     StringRef Name = i.first;
     OS << "// " << Name << "\n";
     for (auto &Overload : i.second) {
       OS << "  { " << Overload.first->getValueAsListOfDefs("Signature").size()
          << ", " << Overload.second << ", " << '"'
          << Overload.first->getValueAsString("Extension") << "\", "
          << Overload.first->getValueAsDef("Version")->getValueAsInt("Version")
for (auto &i : OverloadInfo) {
     CumulativeIndex += Ov.size();
 
     ValidBuiltins.push_back(StringMatcher::StringPair(i.first, RetStmt));
   }
 
   OS << R"(
 // Return 0 if name is not a recognized OpenCL builtin, or an index
 // into a table of declarations if it is an OpenCL builtin.
-std::pair<unsigned, unsigned> isOpenCLBuiltin(llvm::StringRef name) {
+static std::pair<unsigned, unsigned> isOpenCLBuiltin(llvm::StringRef name) {
 
 )";
 
   StringMatcher("name", ValidBuiltins, OS).Emit(0, true);
 
   OS << "  return std::make_pair(0, 0);\n";
   OS << "}\n";
 }