[llvm] [LoopPeel] LCSSA form is destroyed by LoopPeel, preserve it (PR #78696)

[Nikita Popov via llvm-commits]

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@@ -0,0 +1,117 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 4
+; RUN: opt -S -passes=loop-unroll < %s | FileCheck %s
+source_filename = "./reduced.ll"
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128-ni:1-p2:32:8:8:32-ni:2"
+target triple = "x86_64-unknown-linux-gnu"
+
+define void @wombat() gc "statepoint-example" !prof !0 {
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nikic wrote:

Though you'll probably want to run this test case through loop-simplify,lcssa to produce the output that will actually be used after loop canonicalizations. Please also give basic blocks more meaningful names, like bb -> entry, bb1 -> loop1, bb2 -> loop2, etc.

https://github.com/llvm/llvm-project/pull/78696