forked from OSchip/llvm-project
55 lines
1.6 KiB
LLVM
55 lines
1.6 KiB
LLVM
; RUN: opt < %s -indvars -S | FileCheck %s
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; This is regression test for the bug in ScalarEvolution::isKnownPredicate.
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; It does not check whether SCEV is available at loop entry before invoking
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; and utility function isLoopEntryGuardedByCond and that leads to miscompile.
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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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declare void @foo(i64)
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declare void @bar(i32)
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define void @test(i8* %arr) {
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entry:
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br label %outer_header
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outer_header:
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%i = phi i32 [40, %entry], [%i.next, %outer_latch]
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%i.64 = sext i32 %i to i64
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br label %inner_header
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inner_header:
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%j = phi i32 [27, %outer_header], [%j.next, %inner_backedge]
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%j1 = zext i32 %j to i64
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; The next 4 lines are required for avoid widening of %j and
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; SCEV at %cmp would not be AddRec.
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%gep = getelementptr inbounds i8, i8* %arr, i64 %j1
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%ld = load i8, i8* %gep
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%ec = icmp eq i8 %ld, 0
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br i1 %ec, label %return, label %inner_backedge
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inner_backedge:
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%cmp = icmp ult i32 %j, %i
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%s = select i1 %cmp, i32 %i, i32 %j
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; Select should not be simplified because if
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; %i == 26 and %j == 27, %s should be equal to %j.
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; In case of a bug the instruction is simplified to
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; %s = select i1 true, i32 %0, i32 %j
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; CHECK-NOT: %s = select i1 true
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call void @bar(i32 %s)
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%j.next = add nsw i32 %j, -2
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%cond = icmp ult i32 %j, 3
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br i1 %cond, label %outer_latch, label %inner_header
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outer_latch:
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%i.next = add i32 %i, -1
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%cond2 = icmp sgt i32 %i.next, 13
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; This line is just for forcing widening of %i
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call void @foo(i64 %i.64)
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br i1 %cond2, label %outer_header, label %return
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return:
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ret void
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}
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