UPC_MASK
UPC_MASK & CTX_STS_INDIRECT_UPC_INIT);
UPC_MASK & CTX_STS_INDIRECT_UPC_INIT);
CTX_STS_INDIRECT, UPC_MASK & CTX_STS_INDIRECT_UPC_INIT);
savpc &= UPC_MASK;
*endpc = ctx_status & UPC_MASK;
ctx_status & UPC_MASK);
UPC_MASK & upc);