message: Adding -mlir-print-internal-attributes to print attributes with ':' prefixes.
  This enables lit testing of passes that add internal attributes.
diff: @@ -76,6 +76,12 @@ static llvm::cl::opt<bool>
  llvm::cl::desc("Print the generic op form"),
  llvm::cl::init(false), llvm::cl::Hidden);
  +static llvm::cl::opt<bool> printInternalAttributes(
  + "mlir-print-internal-attributes",
  + llvm::cl::desc(
  + "Print internal function and instruction attributes (':' prefix)."),
  + llvm::cl::init(false));
  +
  namespace {
  class ModuleState {
  public:
  @@ -1019,7 +1025,7 @@ void ModulePrinter::printOptionalAttrDict(ArrayRef<NamedAttribute> attrs,
  auto attrName = attr.first.strref();
  // Never print attributes that start with a colon. These are internal
  // attributes that represent location or other internal metadata.
  - if (attrName.startswith(":"))
  + if (!printInternalAttributes && attrName.startswith(":"))
  return;
  // If the caller has requested that this attribute be ignored, then drop it.
  