1. A computer processor implementable method of decoding low-density parity-check (LDPC) code, comprising: receiving a log-likelihood-ratio (LLR) input bitstream; performing a combined bit-deinterleaving and reordering process on the LLR input bitstream without use of a front end memory buffer and storing in a physical memory space, comprising: determining a logical memory address for each LLR bit in the LLR input bitstream, determining a physical memory address for each LLR bit in the LLR input bitstream from logical memory address of the LLR bit, and storing each LLR bit in the LLR input bitstream in the physical memory space according to the determined physical memory address for the LLR bit; decoding the LLR input bitstream stored in the physical memory space; and performing a combined de-reordering and de-mapping process on the decoded LLR input bitstream.