llvm/test/Transforms/LoopVectorize/first-order-recurrence-dead-instructions.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5
; RUN: opt -passes=loop-vectorize -force-vector-width=4 -force-vector-interleave=2 -S %s | FileCheck %s

; Test case for https://github.com/llvm/llvm-project/issues/144212.
define i8 @recurrence_phi_with_same_incoming_values_after_simplifications(i8 %for.start, ptr %dst) {
; CHECK-LABEL: define i8 @recurrence_phi_with_same_incoming_values_after_simplifications(
; CHECK-SAME: i8 [[FOR_START:%.*]], ptr [[DST:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br i1 false, label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i8> poison, i8 [[FOR_START]], i64 0
; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLATINSERT]], <4 x i8> poison, <4 x i32> zeroinitializer
; CHECK-NEXT:    [[TMP0:%.*]] = shufflevector <4 x i8> [[BROADCAST_SPLAT]], <4 x i8> [[BROADCAST_SPLAT]], <4 x i32> <i32 3, i32 4, i32 5, i32 6>
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[OFFSET_IDX:%.*]] = add i32 1, [[INDEX]]
; CHECK-NEXT:    [[TMP1:%.*]] = add i32 [[OFFSET_IDX]], 0
; CHECK-NEXT:    [[TMP2:%.*]] = add i32 [[OFFSET_IDX]], 1
; CHECK-NEXT:    [[TMP3:%.*]] = add i32 [[OFFSET_IDX]], 2
; CHECK-NEXT:    [[TMP4:%.*]] = add i32 [[OFFSET_IDX]], 3
; CHECK-NEXT:    [[TMP5:%.*]] = add i32 [[OFFSET_IDX]], 4
; CHECK-NEXT:    [[TMP6:%.*]] = add i32 [[OFFSET_IDX]], 5
; CHECK-NEXT:    [[TMP7:%.*]] = add i32 [[OFFSET_IDX]], 6
; CHECK-NEXT:    [[TMP8:%.*]] = add i32 [[OFFSET_IDX]], 7
; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP1]]
; CHECK-NEXT:    [[TMP10:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP2]]
; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP3]]
; CHECK-NEXT:    [[TMP12:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP4]]
; CHECK-NEXT:    [[TMP13:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP5]]
; CHECK-NEXT:    [[TMP14:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP6]]
; CHECK-NEXT:    [[TMP15:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP7]]
; CHECK-NEXT:    [[TMP16:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[TMP8]]
; CHECK-NEXT:    [[TMP17:%.*]] = extractelement <4 x i8> [[TMP0]], i32 0
; CHECK-NEXT:    store i8 [[TMP17]], ptr [[TMP9]], align 1
; CHECK-NEXT:    [[TMP18:%.*]] = extractelement <4 x i8> [[TMP0]], i32 1
; CHECK-NEXT:    store i8 [[TMP18]], ptr [[TMP10]], align 1
; CHECK-NEXT:    [[TMP19:%.*]] = extractelement <4 x i8> [[TMP0]], i32 2
; CHECK-NEXT:    store i8 [[TMP19]], ptr [[TMP11]], align 1
; CHECK-NEXT:    [[TMP20:%.*]] = extractelement <4 x i8> [[TMP0]], i32 3
; CHECK-NEXT:    store i8 [[TMP20]], ptr [[TMP12]], align 1
; CHECK-NEXT:    store i8 [[TMP17]], ptr [[TMP13]], align 1
; CHECK-NEXT:    store i8 [[TMP18]], ptr [[TMP14]], align 1
; CHECK-NEXT:    store i8 [[TMP19]], ptr [[TMP15]], align 1
; CHECK-NEXT:    store i8 [[TMP20]], ptr [[TMP16]], align 1
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 8
; CHECK-NEXT:    [[TMP21:%.*]] = icmp eq i32 [[INDEX_NEXT]], -8
; CHECK-NEXT:    br i1 [[TMP21]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    br label %[[SCALAR_PH]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i32 [ -7, %[[MIDDLE_BLOCK]] ], [ 1, %[[ENTRY]] ]
; CHECK-NEXT:    [[SCALAR_RECUR_INIT:%.*]] = phi i8 [ [[FOR_START]], %[[MIDDLE_BLOCK]] ], [ [[FOR_START]], %[[ENTRY]] ]
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i32 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[FOR:%.*]] = phi i8 [ [[SCALAR_RECUR_INIT]], %[[SCALAR_PH]] ], [ [[FOR_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[FOR_NEXT]] = and i8 [[FOR_START]], -1
; CHECK-NEXT:    [[IV_NEXT]] = add i32 [[IV]], 1
; CHECK-NEXT:    [[GEP_DST:%.*]] = getelementptr inbounds i8, ptr [[DST]], i32 [[IV]]
; CHECK-NEXT:    store i8 [[FOR]], ptr [[GEP_DST]], align 1
; CHECK-NEXT:    [[EC:%.*]] = icmp eq i32 [[IV_NEXT]], 0
; CHECK-NEXT:    br i1 [[EC]], label %[[EXIT:.*]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    [[FOR_NEXT_LCSSA:%.*]] = phi i8 [ [[FOR_NEXT]], %[[LOOP]] ]
; CHECK-NEXT:    ret i8 [[FOR_NEXT_LCSSA]]
;
entry:
  br label %loop

loop:
  %iv = phi i32 [ 1, %entry ], [ %iv.next, %loop ]
  %for = phi i8 [ %for.start, %entry ], [ %for.next, %loop ]
  %for.next = and i8 %for.start, -1
  %iv.next = add i32 %iv, 1
  %gep.dst = getelementptr inbounds i8, ptr %dst, i32 %iv
  store i8 %for, ptr %gep.dst
  %ec = icmp eq i32 %iv.next, 0
  br i1 %ec, label %exit, label %loop

exit:
  ret i8 %for.next
}

; %vec.dead will be marked as dead instruction in the vector loop and no recipe
; will be created for it. Make sure a valid sink target is used.
define i32 @sink_after_dead_inst(ptr %A.ptr) {
; CHECK-LABEL: define i32 @sink_after_dead_inst(
; CHECK-SAME: ptr [[A_PTR:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br i1 false, label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i16> [ <i16 0, i16 1, i16 2, i16 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i16> [[VEC_IND]], splat (i16 4)
; CHECK-NEXT:    [[OFFSET_IDX:%.*]] = trunc i32 [[INDEX]] to i16
; CHECK-NEXT:    [[TMP0:%.*]] = add <4 x i16> [[STEP_ADD]], splat (i16 1)
; CHECK-NEXT:    [[TMP1:%.*]] = or <4 x i16> [[TMP0]], [[TMP0]]
; CHECK-NEXT:    [[TMP2:%.*]] = zext <4 x i16> [[TMP1]] to <4 x i32>
; CHECK-NEXT:    [[TMP3:%.*]] = getelementptr i32, ptr [[A_PTR]], i16 [[OFFSET_IDX]]
; CHECK-NEXT:    [[TMP5:%.*]] = getelementptr i32, ptr [[TMP3]], i32 4
; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[TMP3]], align 4
; CHECK-NEXT:    store <4 x i32> zeroinitializer, ptr [[TMP5]], align 4
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 8
; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i16> [[STEP_ADD]], splat (i16 4)
; CHECK-NEXT:    [[TMP6:%.*]] = icmp eq i32 [[INDEX_NEXT]], 16
; CHECK-NEXT:    br i1 [[TMP6]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[VECTOR_RECUR_EXTRACT_FOR_PHI:%.*]] = extractelement <4 x i32> [[TMP2]], i32 2
; CHECK-NEXT:    br label %[[FOR_END:.*]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i16 [ 0, %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[FOR:%.*]] = phi i32 [ 0, %[[SCALAR_PH]] ], [ [[FOR_PREV:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[FOR]], 15
; CHECK-NEXT:    [[C:%.*]] = icmp eq i1 [[CMP]], true
; CHECK-NEXT:    [[VEC_DEAD:%.*]] = and i1 [[C]], true
; CHECK-NEXT:    [[IV_NEXT]] = add i16 [[IV]], 1
; CHECK-NEXT:    [[B1:%.*]] = or i16 [[IV_NEXT]], [[IV_NEXT]]
; CHECK-NEXT:    [[B3:%.*]] = and i1 [[CMP]], [[C]]
; CHECK-NEXT:    [[FOR_PREV]] = zext i16 [[B1]] to i32
; CHECK-NEXT:    [[EXT:%.*]] = zext i1 [[B3]] to i32
; CHECK-NEXT:    [[A_GEP:%.*]] = getelementptr i32, ptr [[A_PTR]], i16 [[IV]]
; CHECK-NEXT:    store i32 0, ptr [[A_GEP]], align 4
; CHECK-NEXT:    br i1 [[VEC_DEAD]], label %[[FOR_END]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
; CHECK:       [[FOR_END]]:
; CHECK-NEXT:    [[FOR_LCSSA:%.*]] = phi i32 [ [[FOR]], %[[LOOP]] ], [ [[VECTOR_RECUR_EXTRACT_FOR_PHI]], %[[MIDDLE_BLOCK]] ]
; CHECK-NEXT:    ret i32 [[FOR_LCSSA]]
;
entry:
  br label %loop

loop:
  %iv = phi i16 [ 0, %entry ], [ %iv.next, %loop ]
  %for = phi i32 [ 0, %entry ], [ %for.prev, %loop ]
  %cmp = icmp eq i32 %for, 15
  %C = icmp eq i1 %cmp, true
  %vec.dead = and i1 %C, 1
  %iv.next = add i16 %iv, 1
  %B1 = or i16 %iv.next, %iv.next
  %B3 = and i1 %cmp, %C
  %for.prev = zext i16 %B1 to i32

  %ext = zext i1 %B3 to i32
  %A.gep = getelementptr i32, ptr %A.ptr, i16 %iv
  store i32 0, ptr %A.gep
  br i1 %vec.dead, label %for.end, label %loop

for.end:
  ret i32 %for
}

; Dead instructions, like the exit condition are not part of the actual VPlan
; and do not need to be sunk. PR44634.
define void @sink_dead_inst(ptr %a) {
; CHECK-LABEL: define void @sink_dead_inst(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br i1 false, label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i16> [ <i16 -27, i16 -26, i16 -25, i16 -24>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[VECTOR_RECUR:%.*]] = phi <4 x i16> [ <i16 poison, i16 poison, i16 poison, i16 0>, %[[VECTOR_PH]] ], [ [[TMP4:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i16> [[VEC_IND]], splat (i16 4)
; CHECK-NEXT:    [[DOTCAST:%.*]] = trunc i32 [[INDEX]] to i16
; CHECK-NEXT:    [[OFFSET_IDX:%.*]] = add i16 -27, [[DOTCAST]]
; CHECK-NEXT:    [[TMP0:%.*]] = add <4 x i16> [[VEC_IND]], splat (i16 1)
; CHECK-NEXT:    [[TMP1:%.*]] = add <4 x i16> [[STEP_ADD]], splat (i16 1)
; CHECK-NEXT:    [[TMP2:%.*]] = zext <4 x i16> [[TMP1]] to <4 x i32>
; CHECK-NEXT:    [[TMP3:%.*]] = add <4 x i16> [[TMP0]], splat (i16 5)
; CHECK-NEXT:    [[TMP4]] = add <4 x i16> [[TMP1]], splat (i16 5)
; CHECK-NEXT:    [[TMP5:%.*]] = shufflevector <4 x i16> [[VECTOR_RECUR]], <4 x i16> [[TMP3]], <4 x i32> <i32 3, i32 4, i32 5, i32 6>
; CHECK-NEXT:    [[TMP6:%.*]] = shufflevector <4 x i16> [[TMP3]], <4 x i16> [[TMP4]], <4 x i32> <i32 3, i32 4, i32 5, i32 6>
; CHECK-NEXT:    [[TMP7:%.*]] = sub <4 x i16> [[TMP5]], splat (i16 10)
; CHECK-NEXT:    [[TMP8:%.*]] = sub <4 x i16> [[TMP6]], splat (i16 10)
; CHECK-NEXT:    [[TMP9:%.*]] = getelementptr i16, ptr [[A]], i16 [[OFFSET_IDX]]
; CHECK-NEXT:    [[TMP11:%.*]] = getelementptr i16, ptr [[TMP9]], i32 4
; CHECK-NEXT:    store <4 x i16> [[TMP7]], ptr [[TMP9]], align 2
; CHECK-NEXT:    store <4 x i16> [[TMP8]], ptr [[TMP11]], align 2
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 8
; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i16> [[STEP_ADD]], splat (i16 4)
; CHECK-NEXT:    [[TMP12:%.*]] = icmp eq i32 [[INDEX_NEXT]], 40
; CHECK-NEXT:    br i1 [[TMP12]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP6:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[VECTOR_RECUR_EXTRACT:%.*]] = extractelement <4 x i16> [[TMP4]], i32 3
; CHECK-NEXT:    [[VECTOR_RECUR_EXTRACT1:%.*]] = extractelement <4 x i32> [[TMP2]], i32 3
; CHECK-NEXT:    br label %[[SCALAR_PH]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i16 [ 13, %[[MIDDLE_BLOCK]] ], [ -27, %[[ENTRY]] ]
; CHECK-NEXT:    [[SCALAR_RECUR_INIT:%.*]] = phi i16 [ [[VECTOR_RECUR_EXTRACT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    [[SCALAR_RECUR_INIT2:%.*]] = phi i32 [ [[VECTOR_RECUR_EXTRACT1]], %[[MIDDLE_BLOCK]] ], [ -27, %[[ENTRY]] ]
; CHECK-NEXT:    br label %[[FOR_COND:.*]]
; CHECK:       [[FOR_COND]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i16 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[FOR_COND]] ]
; CHECK-NEXT:    [[REC_1:%.*]] = phi i16 [ [[SCALAR_RECUR_INIT]], %[[SCALAR_PH]] ], [ [[REC_1_PREV:%.*]], %[[FOR_COND]] ]
; CHECK-NEXT:    [[REC_2:%.*]] = phi i32 [ [[SCALAR_RECUR_INIT2]], %[[SCALAR_PH]] ], [ [[REC_2_PREV:%.*]], %[[FOR_COND]] ]
; CHECK-NEXT:    [[USE_REC_1:%.*]] = sub i16 [[REC_1]], 10
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i32 [[REC_2]], 15
; CHECK-NEXT:    [[IV_NEXT]] = add i16 [[IV]], 1
; CHECK-NEXT:    [[REC_2_PREV]] = zext i16 [[IV_NEXT]] to i32
; CHECK-NEXT:    [[REC_1_PREV]] = add i16 [[IV_NEXT]], 5
; CHECK-NEXT:    [[GEP:%.*]] = getelementptr i16, ptr [[A]], i16 [[IV]]
; CHECK-NEXT:    store i16 [[USE_REC_1]], ptr [[GEP]], align 2
; CHECK-NEXT:    br i1 [[CMP]], label %[[FOR_END:.*]], label %[[FOR_COND]], !llvm.loop [[LOOP7:![0-9]+]]
; CHECK:       [[FOR_END]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %for.cond

for.cond:
  %iv = phi i16 [ -27, %entry ], [ %iv.next, %for.cond ]
  %rec.1 = phi i16 [ 0, %entry ], [ %rec.1.prev, %for.cond ]
  %rec.2 = phi i32 [ -27, %entry ], [ %rec.2.prev, %for.cond ]
  %use.rec.1 = sub i16 %rec.1, 10
  %cmp = icmp eq i32 %rec.2, 15
  %iv.next = add i16 %iv, 1
  %rec.2.prev = zext i16 %iv.next to i32
  %rec.1.prev = add i16 %iv.next, 5
  %gep = getelementptr i16, ptr %a, i16 %iv
  store i16 %use.rec.1, ptr %gep
  br i1 %cmp, label %for.end, label %for.cond

for.end:
  ret void
}

; %rec.1 only has %use.rec.1 as use, which can be removed. This enables %rec.1
; to be removed also.
define void @unused_recurrence(ptr %a) {
; CHECK-LABEL: define void @unused_recurrence(
; CHECK-SAME: ptr [[A:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    br i1 false, label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[INDEX:%.*]] = phi i32 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i16> [ <i16 -27, i16 -26, i16 -25, i16 -24>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[STEP_ADD:%.*]] = add <4 x i16> [[VEC_IND]], splat (i16 4)
; CHECK-NEXT:    [[TMP0:%.*]] = add <4 x i16> [[STEP_ADD]], splat (i16 1)
; CHECK-NEXT:    [[TMP1:%.*]] = add <4 x i16> [[TMP0]], splat (i16 5)
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 8
; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i16> [[STEP_ADD]], splat (i16 4)
; CHECK-NEXT:    [[TMP2:%.*]] = icmp eq i32 [[INDEX_NEXT]], 1024
; CHECK-NEXT:    br i1 [[TMP2]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP8:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[VECTOR_RECUR_EXTRACT:%.*]] = extractelement <4 x i16> [[TMP1]], i32 3
; CHECK-NEXT:    br label %[[SCALAR_PH]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i16 [ 997, %[[MIDDLE_BLOCK]] ], [ -27, %[[ENTRY]] ]
; CHECK-NEXT:    [[SCALAR_RECUR_INIT:%.*]] = phi i16 [ [[VECTOR_RECUR_EXTRACT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    br label %[[FOR_COND:.*]]
; CHECK:       [[FOR_COND]]:
; CHECK-NEXT:    [[IV:%.*]] = phi i16 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[IV_NEXT:%.*]], %[[FOR_COND]] ]
; CHECK-NEXT:    [[REC_1:%.*]] = phi i16 [ [[SCALAR_RECUR_INIT]], %[[SCALAR_PH]] ], [ [[REC_1_PREV:%.*]], %[[FOR_COND]] ]
; CHECK-NEXT:    [[USE_REC_1:%.*]] = sub i16 [[REC_1]], 10
; CHECK-NEXT:    [[IV_NEXT]] = add i16 [[IV]], 1
; CHECK-NEXT:    [[REC_1_PREV]] = add i16 [[IV_NEXT]], 5
; CHECK-NEXT:    [[CMP:%.*]] = icmp eq i16 [[IV]], 1000
; CHECK-NEXT:    br i1 [[CMP]], label %[[FOR_END:.*]], label %[[FOR_COND]], !llvm.loop [[LOOP9:![0-9]+]]
; CHECK:       [[FOR_END]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %for.cond

for.cond:
  %iv = phi i16 [ -27, %entry ], [ %iv.next, %for.cond ]
  %rec.1 = phi i16 [ 0, %entry ], [ %rec.1.prev, %for.cond ]
  %use.rec.1 = sub i16 %rec.1, 10
  %iv.next= add i16 %iv, 1
  %rec.1.prev = add i16 %iv.next, 5
  %cmp = icmp eq i16 %iv, 1000
  br i1 %cmp, label %for.end, label %for.cond

for.end:
  ret void
}