[llvm] [LoopInterchange] Also look at lcssa phis in outer loop latch block (PR #160889)

[Ryotaro Kasuga via llvm-commits]

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@@ -1882,6 +1927,9 @@ bool LoopInterchangeTransform::adjustLoopBranches() {
   assert(OuterLoopPreHeader != OuterLoop->getHeader() &&
          InnerLoopPreHeader != InnerLoop->getHeader() && OuterLoopPreHeader &&
          InnerLoopPreHeader && "Guaranteed by loop-simplify form");
+
+  simplifyLCSSAPhis(OuterLoop, InnerLoop);
+
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kasuga-fj wrote:

nit: is this the right place to call this function? I think it might be better to call this from `moveLCSSAPhis` directly.

https://github.com/llvm/llvm-project/pull/160889