[PATCH] D64509: [SCEV] Compute exit count from overflow test

Wed Jul 10 19:11:53 PDT 2019

shchenz added a comment.

Thanks very much for doing this, this is exactly what I want to do as a follow-up patch for https://reviews.llvm.org/D64422.

This patch looks most good to me except one PowerPC test case.

With this patch, we can get loop exit for more loops, so we get also get more hardware loops in HardwareLoops pass.
As I tested, one PowerPC FIXME test (main1) `llvm/test/CodeGen/PowerPC/negctr.ll` fails if accept this patch. Not sure why this is not showed in your patch. Could you help to have a look? Thanks.

  llc < test/CodeGen/PowerPC/negctr.ll -mcpu=a2 -verify-machineinstrs | FileCheck test/CodeGen/PowerPC/negctr.ll

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D64509/new/

https://reviews.llvm.org/D64509