Contributors:
- Andrew Macleod
- Diego Novillo
- Devang Patel
- Andrew Pinski
Delivery Date:
- 2005-03-31
Benefits:
- Cleaner internals and improve pass scheduling.
- Bounds checking elimination for Java and mudflap.
- Improved propagation opportunities.
Risks:
- Code generation problems in the elimination of bound checks.
- Missing jump threading opportunities when removing the
- integrated propagators that tree-ssa-dom.c uses together with the jump threader.
Description:
- The main goal is to modularize the dominator optimizations into separate passes that use the SSA propagator engine. This adds more flexibility to the scheduling of optimizer passes and, by using the SSA propagation engine, allows more powerful optimizations than what's possible in a dominator tree traversal. The new passes are conditional copy-propagation and value range propagation. Both passes exist in a weaker form inside the current dominator optimizer.