[llvm] [LoopUnroll] Introduce UnrollMaxIterations as a hard cap on how many iterations we try to unroll (PR #78648)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,37 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -passes=loop-unroll -disable-output -debug-only=loop-unroll %s 2>&1 | FileCheck %s
+
+; Validate that loop unroll full doesn't try to fully unroll values whose trip counts are too large.
+
+; CHECK: Exiting block %cont23: TripCount=2147483648, TripMultiple=0, BreakoutTrip=0
+; CHECK-NEXT: Won't unroll; trip count is too large
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nikic wrote:

Check IR instead of debug output.

https://github.com/llvm/llvm-project/pull/78648