[PATCH] D134954: [InstCombine] Switch foldOpIntoPhi() to use InstSimplify

[Nikita Popov via Phabricator via llvm-commits]

nikic added a comment.

Reduced the infinite loop on buildbots to this test case:

  define i64 @test(i1 %c, ptr %arg.ptr, ptr %arg.ptr2) {
  entry:
    br i1 %c, label %if, label %else
  
  if:
    %arg.ptr2.val = load i64, ptr %arg.ptr2, align 8
    br label %join
  
  else:
    %arg.int.ptr = ptrtoint ptr %arg.ptr to i64
    br label %join
  
  join:
    %int.ptr = phi i64 [ %arg.ptr2.val, %if ], [ %arg.int.ptr, %else ]
    %ptr = inttoptr i64 %int.ptr to ptr
    %v = load i64, ptr %ptr, align 8
    ret i64 %v
  }

The conflicting transform appears to be this: https://github.com/llvm/llvm-project/blob/78305720f387ba5c86810a02155bd6c58d22c97c/llvm/lib/Transforms/InstCombine/InstCombinePHI.cpp#L105


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D134954/new/

https://reviews.llvm.org/D134954