llvm-project/llvm/test/Analysis/ScalarEvolution/2012-05-18-LoopPredRecurse.ll

31 lines
996 B
LLVM
Raw Normal View History

; RUN: opt < %s -iv-users -S -disable-output
;
; PR12868: Infinite recursion:
; getUDivExpr()->getZeroExtendExpr()->isLoopBackedgeGuardedBy()
;
; We actually want SCEV simplification to fail gracefully in this
; case, so there's no output to check, just the absense of stack overflow.
@c = common global i8 0, align 1
define i32 @func() {
entry:
br label %for.cond
for.cond: ; preds = %for.body, %entry
%storemerge = phi i8 [ -1, %entry ], [ %inc, %for.body ]
%ui.0 = phi i32 [ undef, %entry ], [ %div, %for.body ]
%tobool = icmp eq i8 %storemerge, 0
br i1 %tobool, label %for.end, label %for.body
for.body: ; preds = %for.cond
%conv = sext i8 %storemerge to i32
%div = lshr i32 %conv, 1
%tobool2 = icmp eq i32 %div, 0
%inc = add i8 %storemerge, 1
br i1 %tobool2, label %for.cond, label %for.end
for.end: ; preds = %for.body, %for.cond
ret i32 0
}