Load partial redundancy elimination.
- GCC's current tree-ssa level PRE does a good job of redundancy elimination (partial and full) of scalar values, but does nothing but full redundancy elimination of loads from memory. This project will teach it how to perform partial redundancy elimination of memory loads. This should enable it to be a lot more effective at reducing the amount of work the RTL level needs to do, as well as do a better job.
Personnel
- Daniel Berlin
Delivery Date
- This optimization will be ready by 2005-12-20.
Benefits
- GCC will eliminate more loads at the tree level.
Modifications Required
- Extension to tree-vn.c to keep track of the VUSES associated with a given value number. Then, tree-ssa-pre.c needs to be extended to translate them through phi nodes, and ensure they are still dominated by the definition point of the memory load.