llvm/test/Transforms/LoopVectorize/tail-folding-iv-outside-user.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 6
; RUN: opt < %s -S -p loop-vectorize -force-vector-width=4 -tail-folding-policy=prefer-fold-tail | FileCheck %s

define i32 @f(ptr noalias %p, i32 %start, i32 %step, i32 %n) {
; CHECK-LABEL: define i32 @f(
; CHECK-SAME: ptr noalias [[P:%.*]], i32 [[START:%.*]], i32 [[STEP:%.*]], i32 [[N:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    [[TMP0:%.*]] = add i32 [[N]], 1
; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    [[N_RND_UP:%.*]] = add i32 [[TMP0]], 3
; CHECK-NEXT:    [[N_MOD_VF:%.*]] = urem i32 [[N_RND_UP]], 4
; CHECK-NEXT:    [[N_VEC:%.*]] = sub i32 [[N_RND_UP]], [[N_MOD_VF]]
; CHECK-NEXT:    [[TMP1:%.*]] = mul i32 [[TMP0]], [[STEP]]
; CHECK-NEXT:    [[TMP2:%.*]] = add i32 [[START]], [[TMP1]]
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[INDEX_NEXT]] = add i32 [[INDEX]], 4
; CHECK-NEXT:    [[TMP3:%.*]] = icmp eq i32 [[INDEX_NEXT]], [[N_VEC]]
; CHECK-NEXT:    br i1 [[TMP3]], label %[[SCALAR_PH:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[IV2_LCSSA:%.*]] = sub i32 [[TMP2]], [[STEP]]
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    ret i32 [[IV2_LCSSA]]
;
entry:
  br label %loop

loop:
  %iv = phi i32 [0, %entry], [%iv.next, %loop]
  %iv2 = phi i32 [%start, %entry], [%iv2.next, %loop]
  %iv.next = add i32 %iv, 1
  %iv2.next = add i32 %iv2, %step
  %ec = icmp eq i32 %iv, %n
  br i1 %ec, label %exit, label %loop

exit:
  ret i32 %iv2
}