Parallelization of WHILE loops on pipelined architectures
β Scribed by Parthasarathy P. Tirumalai; Meng Lee; Michael S. Schlansker
- Book ID
- 104632737
- Publisher
- Springer US
- Year
- 1991
- Tongue
- English
- Weight
- 977 KB
- Volume
- 5
- Category
- Article
- ISSN
- 0920-8542
No coin nor oath required. For personal study only.
β¦ Synopsis
Modulo scheduling theory can be applied successfully to overlap Fortran DO loops on pipelined computers issuing multiple operations per cycle both with and without special loop architectural support. This paper shows that a broader class of loops--REPEAT-UNTIL, WHILE, and loops with more than one exit, in which the trip count is not known beforehand--can also be overlapped efficiently on multiple-issue pipelined machines. The approach is described with respect to a specific machine model, but it can be extended to other models. Special features in the architecture, as well as compiler representations for accelerating these loop constructs, are discussed. Performance results are presented for a few select examples.
π SIMILAR VOLUMES
A considerable part of program execution time is consumed by loops, so that loop optimization is highly effective especially for the innermost loops of a program. Software pipelining and loop unrolling are known methods for loop optimization. Software pipelining is advantageous in that the code beco
Considering a dynamic conditional loop S~, i.e. involving an if-then-else with a dynamic condition, our aim is to restructure ~ in order to extract the inherent parallelism. Assuming the dependence distances (DD) carried by ~ to be non-constant, we first study their corresponding signs. This leads t