Expand description
A collection of optimization passes.
Each of these modules are a collection of typical code optimisation passes.
Currently there is no pass manager, as there are only a couple of passes, but this is something which will be added in the future.
So each of the functions under this module will return a boolean indicating whether a modification to the IR was made. Typically the passes will be just re-run until they no longer make any such modifications, implying they’ve optimized as much possible.
When writing passes one should keep in mind that when a modification is made then any iterators over blocks or instructions can be invalidated, and starting over is a safer option than trying to attempt multiple changes at once.
Re-exports§
pub use arg_demotion::*;pub use const_demotion::*;pub use constants::*;pub use conditional_constprop::*;pub use cse::*;pub use dce::*;pub use inline::*;pub use mem2reg::*;pub use memcpyopt::*;pub use misc_demotion::*;pub use ret_demotion::*;pub use simplify_cfg::*;pub use sroa::*;pub use fn_dedup::*;
Modules§
- arg_
demotion - conditional_
constprop - When a value is guaranteed to have a constant value in a region of the CFG, this optimization replaces uses of that value with the constant in that region.
- const_
demotion - constants
- Optimization passes for manipulating constant values.
- cse
- Value numbering based common subexpression elimination. Reference: Value Driven Redundancy Elimination - Loren Taylor Simpson.
- dce
- Dead Code Elimination
- fn_
dedup - Deduplicate functions.
- inline
- Function inlining.
- mem2reg
- memcpyopt
- Optimisations related to mem_copy.
- misc_
demotion - ret_
demotion - simplify_
cfg - Simplify Control Flow Graph
- sroa
- Scalar Replacement of Aggregates