Variables spilled on both branch legs need to be assigned to the same spilling slot.
These affinities can be transitive through multiple merge blocks.
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
Converting to 'Conventional SSA Form' ensures correctness w.r.t. spilling of phi nodes.
Previously, it was possible that phi operands have intersecting live-ranges, and thus,
couldn't get spilled to the same spilling slot. For this reason, ACO tried to avoid to
spill phis, even if it was beneficial.
This patch implements a conversion pass which is currently only called if spilling is necessary.
Reviewed-by: Rhys Perry <pendingchaos02@gmail.com>
ACO (short for AMD Compiler) is a new compiler backend with the goal to replace
LLVM for Radeon hardware for the RADV driver.
ACO currently supports only VS, PS and CS on VI and Vega.
There are some optimizations missing because of unmerged NIR changes
which may decrease performance.
Full commit history can be found at
https://github.com/daniel-schuermann/mesa/commits/backend
Co-authored-by: Daniel Schürmann <daniel@schuermann.dev>
Co-authored-by: Rhys Perry <pendingchaos02@gmail.com>
Co-authored-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
Co-authored-by: Connor Abbott <cwabbott0@gmail.com>
Co-authored-by: Michael Schellenberger Costa <mschellenbergercosta@googlemail.com>
Co-authored-by: Timur Kristóf <timur.kristof@gmail.com>
Acked-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Acked-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
