llvm-project

4ab87ffd - [SCCP] Enable PredicateInfo for non-interprocedural SCCP (#153003)

[SCCP] Enable PredicateInfo for non-interprocedural SCCP (#153003) SCCP can use PredicateInfo to constrain ranges based on assume and branch conditions. Currently, this is only enabled during IPSCCP. This enables it for SCCP as well, which runs after functions have already been simplified, while IPSCCP runs pre-inline. To a large degree, CVP already handles range-based optimizations, but SCCP is more reliable for the cases it can handle. In particular, SCCP works reliably inside loops, which is something that CVP struggles with due to LVI cycles. I have made various optimizations to make PredicateInfo more efficient, but unfortunately this still has significant compile-time cost (around 0.1-0.2%).