llvm/test/Transforms/LoopVectorize/X86/pr131359-dead-for-splice.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 5
; RUN: opt -p loop-vectorize -S %s | FileCheck %s

; If a FOR isn't used the VPInstruction::FirstOrderRecurrenceSplice will be dead
; and won't be costed in the VPlan cost model. Make sure we account for this
; simplifcation in comparison to the legacy cost model.

target triple = "x86_64"

define void @no_use() {
; CHECK-LABEL: define void @no_use() {
; 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:    [[VECTOR_RECUR:%.*]] = phi <4 x i32> [ <i32 poison, i32 poison, i32 poison, i32 0>, %[[VECTOR_PH]] ], [ [[STEP_ADD:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ <i32 0, i32 1, i32 2, i32 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[STEP_ADD]] = add <4 x i32> [[VEC_IND]], splat (i32 4)
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 8
; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i32> [[STEP_ADD]], splat (i32 4)
; CHECK-NEXT:    [[TMP0:%.*]] = icmp eq i32 [[INDEX_NEXT]], 40
; CHECK-NEXT:    br i1 [[TMP0]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[VECTOR_RECUR_EXTRACT:%.*]] = extractelement <4 x i32> [[STEP_ADD]], i32 3
; CHECK-NEXT:    br i1 false, label %[[EXIT:.*]], label %[[SCALAR_PH]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[SCALAR_RECUR_INIT:%.*]] = phi i32 [ [[VECTOR_RECUR_EXTRACT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i32 [ 40, %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[FOR:%.*]] = phi i32 [ [[SCALAR_RECUR_INIT]], %[[SCALAR_PH]] ], [ [[E_0_I:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[E_0_I]] = phi i32 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[INC_I:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[INC_I]] = add i32 [[E_0_I]], 1
; CHECK-NEXT:    [[EXITCOND_NOT_I:%.*]] = icmp eq i32 [[E_0_I]], 43
; CHECK-NEXT:    br i1 [[EXITCOND_NOT_I]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP3:![0-9]+]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %for = phi i32 [ 0, %entry ], [ %iv, %loop ]
  %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ]
  %iv.next = add i32 %iv, 1
  %exitcond.not.i = icmp eq i32 %iv, 43
  br i1 %exitcond.not.i, label %exit, label %loop

exit:
  ret void
}

define void @dead_use() {
; CHECK-LABEL: define void @dead_use() {
; 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:    [[VECTOR_RECUR:%.*]] = phi <4 x i32> [ <i32 poison, i32 poison, i32 poison, i32 0>, %[[VECTOR_PH]] ], [ [[STEP_ADD:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i32> [ <i32 0, i32 1, i32 2, i32 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[VECTOR_BODY]] ]
; CHECK-NEXT:    [[STEP_ADD]] = add <4 x i32> [[VEC_IND]], splat (i32 4)
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i32 [[INDEX]], 8
; CHECK-NEXT:    [[VEC_IND_NEXT]] = add <4 x i32> [[STEP_ADD]], splat (i32 4)
; CHECK-NEXT:    [[TMP0:%.*]] = icmp eq i32 [[INDEX_NEXT]], 40
; CHECK-NEXT:    br i1 [[TMP0]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP4:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[VECTOR_RECUR_EXTRACT:%.*]] = extractelement <4 x i32> [[STEP_ADD]], i32 3
; CHECK-NEXT:    br i1 false, label %[[EXIT:.*]], label %[[SCALAR_PH]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[SCALAR_RECUR_INIT:%.*]] = phi i32 [ [[VECTOR_RECUR_EXTRACT]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i32 [ 40, %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    br label %[[LOOP:.*]]
; CHECK:       [[LOOP]]:
; CHECK-NEXT:    [[D_0_I:%.*]] = phi i32 [ [[SCALAR_RECUR_INIT]], %[[SCALAR_PH]] ], [ [[E_0_I:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[E_0_I]] = phi i32 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[INC_I:%.*]], %[[LOOP]] ]
; CHECK-NEXT:    [[DEAD:%.*]] = add i32 [[D_0_I]], 1
; CHECK-NEXT:    [[INC_I]] = add i32 [[E_0_I]], 1
; CHECK-NEXT:    [[EXITCOND_NOT_I:%.*]] = icmp eq i32 [[E_0_I]], 43
; CHECK-NEXT:    br i1 [[EXITCOND_NOT_I]], label %[[EXIT]], label %[[LOOP]], !llvm.loop [[LOOP5:![0-9]+]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %for = phi i32 [ 0, %entry ], [ %iv, %loop ]
  %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ]
  %dead = add i32 %for, 1
  %iv.next = add i32 %iv, 1
  %exitcond.not.i = icmp eq i32 %iv, 43
  br i1 %exitcond.not.i, label %exit, label %loop

exit:
  ret void
}