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llvm-project/llvm/test/Transforms/LoopDeletion/multiple-exit-conditions.ll

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Make LoopDeletion check the maximum backedge taken count, rather than the exact backedge taken count, when checking for infinite loops. This allows it to delete loops with multiple exit conditions. llvm-svn: 84952
2009-10-24 01:10:01 +08:00
; RUN: opt < %s -loop-deletion -S | FileCheck %s
[PM] Teach LoopDeletion to correctly update the LPM when loops are deleted. I've expanded its test coverage a bit including adding one test that will crash clearly without this change. llvm-svn: 292332
2017-01-18 10:41:26 +08:00
; RUN: opt < %s -passes='loop(loop-deletion)' -S | FileCheck %s
Make LoopDeletion check the maximum backedge taken count, rather than the exact backedge taken count, when checking for infinite loops. This allows it to delete loops with multiple exit conditions. llvm-svn: 84952
2009-10-24 01:10:01 +08:00
; ScalarEvolution can prove the loop iteration is finite, even though
; it can't represent the exact trip count as an expression. That's
; good enough to let the loop be deleted.
; CHECK: entry:
; CHECK-NEXT: br label %return
; CHECK: return:
; CHECK-NEXT: ret void
define void @foo(i64 %n, i64 %m) nounwind {
entry:
br label %bb
bb:
%x.0 = phi i64 [ 0, %entry ], [ %t0, %bb ]
%t0 = add i64 %x.0, 1
%t1 = icmp slt i64 %x.0, %n
%t3 = icmp sgt i64 %x.0, %m
%t4 = and i1 %t1, %t3
br i1 %t4, label %bb, label %return
return:
ret void
}