[all-commits] [llvm/llvm-project] 553f88: [DomTree] Reduce number of hash table lookups (NFC...

[Nikita Popov via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 553f8853db1a41543bcd3c7c9a6e0f75c537d2f9
      https://github.com/llvm/llvm-project/commit/553f8853db1a41543bcd3c7c9a6e0f75c537d2f9
  Author: Nikita Popov <npopov at redhat.com>
  Date:   2023-11-27 (Mon, 27 Nov 2023)

  Changed paths:
    M llvm/include/llvm/Support/GenericDomTreeConstruction.h

  Log Message:
  -----------
  [DomTree] Reduce number of hash table lookups (NFC) (#73097)

Inside runSemiNCA(), create a direct mapping from node number of node
info, so we can save the node number -> node pointer -> node info lookup
in many cases.

To allow this in more cases, change Label to a node number instead of
node pointer.

I've limited this to runSemiNCA() for now, because we have the
convenient property there that no new node infos will be added, so we
don't have to worry about pointer invalidation.

This gives a pretty nice compile-time improvement of about 0.4%.