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ad2555c9a3
exact backedge taken count, when checking for infinite loops. This allows it to delete loops with multiple exit conditions. llvm-svn: 84952
28 lines
617 B
LLVM
28 lines
617 B
LLVM
; RUN: opt < %s -loop-deletion -S | FileCheck %s
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; ScalarEvolution can prove the loop iteration is finite, even though
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; it can't represent the exact trip count as an expression. That's
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; good enough to let the loop be deleted.
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; CHECK: entry:
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; CHECK-NEXT: br label %return
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; CHECK: return:
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; CHECK-NEXT: ret void
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define void @foo(i64 %n, i64 %m) nounwind {
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entry:
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br label %bb
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bb:
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%x.0 = phi i64 [ 0, %entry ], [ %t0, %bb ]
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%t0 = add i64 %x.0, 1
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%t1 = icmp slt i64 %x.0, %n
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%t3 = icmp sgt i64 %x.0, %m
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%t4 = and i1 %t1, %t3
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br i1 %t4, label %bb, label %return
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return:
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ret void
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}
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