Mircea Trofin 73c3b7337b [ctx_prof] Add support for ICP (#105469) ...

An overload of `llvm::promoteCallWithIfThenElse` that updates the contextual profile.

High-level, this is very simple: after creating the `if... then (direct call) else (indirect call)` structure, we instrument the new callsites and BBs (the instrumentation will help with tracking for other IPO transformations, and, ultimately, to match counter values before flattening to `MD_prof`).

In more detail:

- move the callsite instrumentation of the indirect call to the `else` BB, before the indirect call
- create a new callsite instrumentation for the direct call
- create instrumentation for both the `then` and `else` BBs - we could instrument just one (MST-style) but we're not running the binary with this instrumentation, and at most this would save some space (less counters tracked). For simplicity instrumenting both at this point
- update each context belonging to the caller by updating the counters, and moving the indirect callee to the new, direct callsite ID

Issue #89287

2024-08-27 15:50:13 -07:00

28 KiB

Raw Blame History

View Raw