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; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -indvars -S | FileCheck %s

target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"

; It is okay to do LFTR on this loop even though the trip count is a
; division because in this case the division can be optimized to a
; shift.

define void @foo(i8* %a, i8 %n) nounwind uwtable ssp {
; CHECK-LABEL: @foo(
; CHECK-NEXT:  entry:
; CHECK-NEXT:    [[E:%.*]] = icmp sgt i8 [[N:%.*]], 3
; CHECK-NEXT:    br i1 [[E]], label [[LOOP_PREHEADER:%.*]], label [[EXIT:%.*]]
; CHECK:       loop.preheader:
; CHECK-NEXT:    [[TMP0:%.*]] = add i8 [[N]], 3
; CHECK-NEXT:    [[TMP1:%.*]] = lshr i8 [[TMP0]], 2
; CHECK-NEXT:    [[TMP2:%.*]] = add i8 [[TMP1]], 1
; CHECK-NEXT:    br label [[LOOP:%.*]]
; CHECK:       loop:
; CHECK-NEXT:    [[I1:%.*]] = phi i8 [ [[I1_INC:%.*]], [[LOOP]] ], [ 0, [[LOOP_PREHEADER]] ]
; CHECK-NEXT:    [[I1_INC]] = add nuw nsw i8 [[I1]], 1
; CHECK-NEXT:    store volatile i8 0, i8* [[A:%.*]]
; CHECK-NEXT:    [[EXITCOND:%.*]] = icmp ne i8 [[I1_INC]], [[TMP2]]
; CHECK-NEXT:    br i1 [[EXITCOND]], label [[LOOP]], label [[EXIT_LOOPEXIT:%.*]]
; CHECK:       exit.loopexit:
; CHECK-NEXT:    br label [[EXIT]]
; CHECK:       exit:
; CHECK-NEXT:    ret void
;
entry:
  %e = icmp sgt i8 %n, 3
  br i1 %e, label %loop, label %exit

loop:
  %i = phi i8 [ 0, %entry ], [ %i.inc, %loop ]
  %i1 = phi i8 [ 0, %entry ], [ %i1.inc, %loop ]
  %i.inc = add nsw i8 %i, 4
  %i1.inc = add i8 %i1, 1
  store volatile i8 0, i8* %a
  %c = icmp slt i8 %i, %n
  br i1 %c, label %loop, label %exit

exit:
  ret void
}