[PATCH] D38177: [LoopPredication] Support ule, sle latch predicates

[Max Kazantsev via Phabricator via llvm-commits]

mkazantsev added inline comments.


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Comment at: test/Transforms/LoopPredication/basic.ll:158
+; CHECK: loop.preheader:
+; CHECK: [[first_iteration_check:[^ ]+]] = icmp ult i32 0, %length
+; CHECK-NEXT: [[limit_check:[^ ]+]] = icmp slt i32 %n, %length
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Consider case `%n = 10, %length = -100`. The original code will successfully pass through the guard (because `0 <u -100` is true) and then executes normally. After the loop is predicated, the condition `icmp slt i32 %n, %length` becomes false, and we don't go to the loop and deoptimize. Is it a problem?


https://reviews.llvm.org/D38177