[PATCH] D128779: [GuardWidening] Add tests showing the incorrect behavior of GW wrt poison

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: llvm/test/Transforms/GuardWidening/posion.ll:14
+; The first two checks are in the first basic block and guard widening
+; consider them as profitable to combine.
+; When c4 and c3 are considered, number of check becomes more than two
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nit: considers


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Comment at: llvm/test/Transforms/GuardWidening/posion.ll:16
+; When c4 and c3 are considered, number of check becomes more than two
+; and combineRangeCheck consider then as profitable even if they are in
+; different basic blocks.
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nit: consider then -> considers them


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Comment at: llvm/test/Transforms/GuardWidening/posion.ll:22
+
+define void @combine_range_checks(i32 %x) {
+; CHECK-LABEL: @combine_range_checks(
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please add FIXME into the comment


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Comment at: llvm/test/Transforms/GuardWidening/posion.ll:73
+; CHECK-NEXT:    [[WIDE_CHK:%.*]] = and i1 [[COND_0]], [[COND_2]]
+; CHECK-NEXT:    call void (i1, ...) @llvm.experimental.guard(i1 [[WIDE_CHK]]) [ "deopt"() ]
+; CHECK-NEXT:    br label [[LOOP:%.*]]
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I don't quite get it. `COND_0` here is not poison, why would logical and not help?


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D128779/new/

https://reviews.llvm.org/D128779