[all-commits] [llvm/llvm-project] f492a4: [SCEV] Simplify forgetSymbolicName() (NFCI)

[Nikita Popov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: f492a414bad782ae4202d2af9d3408f8e727599d
      https://github.com/llvm/llvm-project/commit/f492a414bad782ae4202d2af9d3408f8e727599d
  Author: Nikita Popov <nikita.ppv at gmail.com>
  Date:   2021-11-27 (Sat, 27 Nov 2021)

  Changed paths:
    M llvm/include/llvm/Analysis/ScalarEvolution.h
    M llvm/lib/Analysis/ScalarEvolution.cpp

  Log Message:
  -----------
  [SCEV] Simplify forgetSymbolicName() (NFCI)

With the recently introduced tracking as well as D113349, we can
greatly simplify forgetSymbolicName(). In fact, we can simply
replace it with forgetMemoizedResults().

What forgetSymbolicName() used to do is to walk the IR use-def
chain to find all SCEVs that mention the SymbolicName. However,
thanks to use tracking, we can now determine the relevant SCEVs
in a more direct way. D113349 is needed to also clear out the
actual IR to SCEV mapping in ValueExprMap.

Differential Revision: https://reviews.llvm.org/D114263