BitValue Inference: Detecting and Exploiting Narrow Bitwidth Computations
Abstract
The authors present a compiler algorithm called BitValue, which can discover unused and constant bits in dusty-deck C programs. BitValue uses forward and backward dataflow analyses, generalizing constant-folding and dead-code detection at the bit-level. This algorithm enables compiler optimizations targeting special processor architectures for computing on non-standard bitwidths. Using this algorithm, they show that up to 36% of the computed bytes are thrown away. Also, they show that on average 26.8% of the values computed require 16 bits or less (for programs from SpecINT95 and Mediabench). A compiler for reconfigurable hardware uses this algorithm to achieve substantial reductions (up to 20-fold) in the size of the synthesized circuits.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2000
- Accession Number
- ADA458537
Entities
People
- Mihai Budiu
- Seth C. Goldstein
Organizations
- Carnegie Mellon University