A simple and fast scheme for code compression for VLIW processors

A Bitmask-based Code Compression Technique for Embedded Systems

“…Table 2 compares our approach with the existing code compression techniques. Our technique improves the code compression efficiency by 15% compared to the existing dictionary based techniques [8,9]. The compression efficiency of our technique is comparable to the stateof-the-art compression techniques (IBM CodePack [7] and SAMC [6]).…”

“…The basic idea is to take advantage of commonly occurring instruction sequences by using a dictionary. Recently proposed techniques [8,9] improve the dictionary-based compression technique by considering mismatches. The basic idea is to create instruction matches by remembering a few bit positions.…”

“…Dictionary-based code compression techniques are popular because they offer both good compression ratio and fast decompression scheme. Recently proposed techniques [8,9] improve standard dictionary-based compression by considering mismatches. This paper makes two important contributions: i) it provides a cost-benefit analysis framework for improving the compression ratio by creating more matching patterns, and ii) it develops an efficient code compression technique using bitmasks to improve the compression ratio without introducing any decompression penalty.…”

Compiler optimization and ordering effects on VLIW code compression

“…The code compression techniques applied to date on multipleissue processors (particularly the more original rigid VLIW processors, but also recently targeting variable execution set architectures) are limited to the works of Nam et al [21], Ishiura and Yamaguchi [10], Prakash et al [20], Xie et al [23][24][25] and Larin and Conte [11]. This is only a subset of the techniques available for both data compression and single-issue code compression.…”

“…Prakash et al [20] present a dictionary based encoding scheme that divides instructions into 2 16-bit halves. For each half, a dictionary is constructed that contains a choice set of vectors such that a majority of the vectors used throughout the program in that half of the instruction differ by one of the dictionary vectors by a small Hamming Distance (the Hamming Distance between two vectors is the number of bits that are different).…”