[PATCH] D51664: [IR] Lazily number instructions for local dominance queries

[Chris Lattner via Phabricator via llvm-commits]

lattner added a comment.

As I mentioned on llvmdev, I'm strongly opposed to this patch without a significant amount of analysis and diligence applied to it.  I'm concerned about both memory and compile time impact.  We don't just add random caches to the core IR to speed up particular clients.  We care a lot about sizeof(Instruction) and its subclasses, and this adds bloat to all of them.  Similarly, you don't seem interested in evaluating "tricks" to make this efficient in practice (sparse numbering), nor have you evaluated other implementation choices that will probably also work with less impact.  Let's continue discussing this on llvm-dev.


https://reviews.llvm.org/D51664