28 lines
959 B
LLVM
28 lines
959 B
LLVM
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; RUN: opt < %s -analyze -enable-new-pm=0 -scalar-evolution | FileCheck %s
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; RUN: opt < %s -disable-output "-passes=print<scalar-evolution>" 2>&1 | FileCheck %s
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target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
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target triple = "x86_64-unknown-linux-gnu"
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; Previously in this case the max backedge count would be computed as 1/0, which
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; is correct but undesirable. It would also not fold as a constant, tripping
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; asserts in SCEV.
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define void @pluto(i32 %arg) {
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; CHECK-LABEL: Classifying expressions for: @pluto
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; CHECK: Loop %bb2: max backedge-taken count is 2
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bb:
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%tmp = ashr i32 %arg, 31
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%tmp1 = add nsw i32 %tmp, 2
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br label %bb2
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bb2: ; preds = %bb2, %bb
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%tmp3 = phi i32 [ 0, %bb ], [ %tmp4, %bb2 ]
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%tmp4 = add nuw nsw i32 %tmp1, %tmp3
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%tmp5 = icmp ult i32 %tmp4, 2
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br i1 %tmp5, label %bb2, label %bb6
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bb6: ; preds = %bb2
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ret void
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}
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