Function LLVMAddNamedMetadataOperand 

pub unsafe extern "C" fn LLVMAddNamedMetadataOperand(
    M: LLVMModuleRef,
    Name: *const c_char,
    Val: LLVMValueRef,
)

Add an operand to named metadata.

@see llvm::Module::getNamedMetadata() @see llvm::MDNode::addOperand()