Use proper type for getLLVMIntrinsicID

At one point we were probably trying to avoid including
llvm/IR/Intrinsics.h in Builtins.h but that ship has sailed.

No functionality change.

Author: jrose-apple

include/swift/AST/Builtins.h

@@ -80,9 +80,9 @@ StringRef getBuiltinBaseName(ASTContext &C, StringRef Name,
                              SmallVectorImpl<Type> &Types);
 
 /// Given an LLVM IR intrinsic name with argument types remove (e.g. like
-/// "bswap") return the LLVM IR IntrinsicID for the intrinsic or 0 if the
-/// intrinsic name doesn't match anything.
-unsigned getLLVMIntrinsicID(StringRef Name);
+/// "bswap") return the LLVM IR IntrinsicID for the intrinsic or not_intrinsic
+/// (0) if the intrinsic name doesn't match anything.
+llvm::Intrinsic::ID getLLVMIntrinsicID(StringRef Name);
 
 /// Get the LLVM intrinsic ID that corresponds to the given builtin with
 /// overflow.

lib/AST/Builtins.cpp

@@ -1225,10 +1225,7 @@ static const char *const IntrinsicNameTable[] = {
 #include "llvm/IR/IntrinsicImpl.inc"
 #undef GET_INTRINSIC_TARGET_DATA
 
-/// getLLVMIntrinsicID - Given an LLVM IR intrinsic name with argument types
-/// removed (e.g. like "bswap") return the LLVM IR IntrinsicID for the intrinsic
-/// or 0 if the intrinsic name doesn't match anything.
-unsigned swift::getLLVMIntrinsicID(StringRef InName) {
+llvm::Intrinsic::ID swift::getLLVMIntrinsicID(StringRef InName) {
   using namespace llvm;
 
   // Swift intrinsic names start with int_.
@@ -1321,12 +1318,11 @@ static Type DecodeIntrinsicType(ArrayRef<llvm::Intrinsic::IITDescriptor> &Table,
 
 /// \returns true on success, false on failure.
 static bool
-getSwiftFunctionTypeForIntrinsic(unsigned iid, ArrayRef<Type> TypeArgs,
+getSwiftFunctionTypeForIntrinsic(llvm::Intrinsic::ID ID,
+                                 ArrayRef<Type> TypeArgs,
                                  ASTContext &Context,
                                  SmallVectorImpl<Type> &ArgElts,
                                  Type &ResultTy, FunctionType::ExtInfo &Info) {
-  llvm::Intrinsic::ID ID = (llvm::Intrinsic::ID)iid;
-  
   typedef llvm::Intrinsic::IITDescriptor IITDescriptor;
   SmallVector<IITDescriptor, 8> Table;
   getIntrinsicInfoTableEntries(ID, Table);
@@ -1439,7 +1435,7 @@ ValueDecl *swift::getBuiltinValueDecl(ASTContext &Context, Identifier Id) {
 
   // If this is the name of an LLVM intrinsic, cons up a swift function with a
   // type that matches the IR types.
-  if (unsigned ID = getLLVMIntrinsicID(OperationName)) {
+  if (llvm::Intrinsic::ID ID = getLLVMIntrinsicID(OperationName)) {
     SmallVector<Type, 8> ArgElts;
     Type ResultTy;
     FunctionType::ExtInfo Info;

lib/SIL/SILModule.cpp

@@ -275,7 +275,7 @@ const IntrinsicInfo &SILModule::getIntrinsicInfo(Identifier ID) {
 
   // Otherwise, lookup the ID and Type and store them in the map.
   StringRef NameRef = getBuiltinBaseName(getASTContext(), ID.str(), Info.Types);
-  Info.ID = (llvm::Intrinsic::ID)getLLVMIntrinsicID(NameRef);
+  Info.ID = getLLVMIntrinsicID(NameRef);
 
   return Info;
 }