This commit adds in two new features to the ML regalloc eviction
analysis that can be used in ML models, a vector of MBB frequencies and
a vector of indicies mapping instructions to their corresponding basic
blocks. This will allow for further experimentation with per-instruction
features and give a lot more flexibility for future experimentation over
how we're extracting MBB frequency data currently.
Reviewed By: mtrofin, jacobhegna
Differential Revision: https://reviews.llvm.org/D134166
This patch adds in instruction based features to the regalloc advisor
gated behind a flag so a user can decide at runtime whether or not they
want to enable the feature. The features are only enabled when LLVM is
compiled in MLGO develpment mode (LLVM_HAVE_TF_API) is set to true.
To extract the instruction features, I'm taking a list of segments from
each LiveInterval and noting the start and end SlotIndices. This list is then
sorted based on the start SlotIndex and I iterate through each SlotIndex
to grab instructions, making sure to check for overlaps. This results in
a vector of opcodes and binary mapping matrix that maps live ranges to the
opcodes of the instructions within that LR.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D131930
Aiden Grossman