40 lines
1.2 KiB
LLVM
40 lines
1.2 KiB
LLVM
; RUN: opt < %s -analyze -iv-users -S | FileCheck %s
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; This is a regression test for the commit rL327362.
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target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:1"
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target triple = "x86_64-unknown-linux-gnu"
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define void @test(i64 %a, i64* %p) {
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entry:
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br label %first_loop
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first_loop:
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%i = phi i64 [20, %entry], [%i.next, %first_loop]
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%i.next = add nuw nsw i64 %i, 1
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%cond1 = icmp ult i64 %i.next, %a
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br i1 %cond1, label %first_loop, label %middle_block
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middle_block:
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%b = load i64, i64* %p
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%cmp = icmp ult i64 %i, %b
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; When SCEV will try to compute the initial value for %j
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; it will observe umax generated by this select.
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; When it will try to simplify this umax it will invoke
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; isKnownPredicate with AddRec for %i and unknown SCEV for %b.
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; As a result we find MDL == first_loop where %b is not available
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; at loop entry.
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; CHECK: IV Users for loop %second_loop with backedge-taken count{{.*}}umax
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%s = select i1 %cmp, i64 %i, i64 %b
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br label %second_loop
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second_loop:
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%j = phi i64 [%s, %middle_block], [%j.next, %second_loop]
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%j.next = add nuw nsw i64 %j, 1
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%cond2 = icmp ult i64 %j.next, 100
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br i1 %cond2, label %second_loop, label %return
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return:
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ret void
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}
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