Function mlirPassManagerEnableIRPrinting 

pub unsafe extern "C" fn mlirPassManagerEnableIRPrinting(
    passManager: MlirPassManager,
    printBeforeAll: bool,
    printAfterAll: bool,
    printModuleScope: bool,
    printAfterOnlyOnChange: bool,
    printAfterOnlyOnFailure: bool,
    flags: MlirOpPrintingFlags,
    treePrintingPath: MlirStringRef,
)

Enable IR printing. The treePrintingPath argument is an optional path to a directory where the dumps will be produced. If it isn’t provided then dumps are produced to stderr.