[PATCH] D39455: [CodeGen] Add initial support for union members in TBAA

[Hal Finkel via Phabricator via cfe-commits]

hfinkel added a comment.

In https://reviews.llvm.org/D39455#943182, @aheejin wrote:

> Once you confirm the bug, could you possibly revert the patch?


I agree. We should revert this. The relevant part of the test case is:

  short *q;
  p->u.vec[i] = 0;
  q = &p->u.vec[16];
  *q = 1;
  return p->u.vec[i];

demonstrating that you can't use "union member" as the access type here. You need to use the actual access type, or something derived from it, because non-type-changing scalar accesses are still allowed to alias with the union-member accesses.


Repository:
  rL LLVM

https://reviews.llvm.org/D39455