llvm/test/Transforms/LoopVectorize/RISCV/vector-loop-backedge-elimination-with-evl.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
; RUN: opt %s -S -mtriple riscv64 -passes=loop-vectorize --tail-folding-policy=must-fold-tail -force-tail-folding-style=data-with-evl -riscv-v-min-trip-count=0 -force-target-instruction-cost=1 -mattr=+v | FileCheck %s

; Check canonical-iv is removed in single-iteration loop
define void @foo(ptr %arg) #0 {
; CHECK-LABEL: define void @foo(
; CHECK-SAME: ptr [[ARG:%.*]]) #[[ATTR0:[0-9]+]] {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    call void @llvm.vp.store.nxv2i64.p0(<vscale x 2 x i64> zeroinitializer, ptr align 8 [[ARG]], <vscale x 2 x i1> splat (i1 true), i32 3)
; CHECK-NEXT:    br label %[[MIDDLE_BLOCK:.*]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    br label %[[EXIT:.*]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
  %gep = getelementptr [3 x i64], ptr %arg, i64 0, i64 %iv
  store i64 0, ptr %gep, align 8
  %iv.next = add i64 %iv, 1
  %cond = icmp eq i64 %iv.next, 3
  br i1 %cond, label %exit, label %loop

exit:
  ret void
}

define i32 @test_remove_iv(i32 %start) #0 {
; CHECK-LABEL: define i32 @test_remove_iv(
; CHECK-SAME: i32 [[START:%.*]]) #[[ATTR0]] {
; CHECK-NEXT:  [[ENTRY:.*:]]
; CHECK-NEXT:    br label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    [[TMP2:%.*]] = insertelement <vscale x 4 x i32> zeroinitializer, i32 [[START]], i32 0
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[TMP3:%.*]] = xor <vscale x 4 x i32> [[TMP2]], splat (i32 3)
; CHECK-NEXT:    [[TMP5:%.*]] = call <vscale x 4 x i32> @llvm.vp.merge.nxv4i32(<vscale x 4 x i1> splat (i1 true), <vscale x 4 x i32> [[TMP3]], <vscale x 4 x i32> [[TMP2]], i32 6)
; CHECK-NEXT:    br label %[[MIDDLE_BLOCK:.*]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[TMP6:%.*]] = call i32 @llvm.vector.reduce.xor.nxv4i32(<vscale x 4 x i32> [[TMP5]])
; CHECK-NEXT:    br label %[[EXIT:.*]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret i32 [[TMP6]]
;
entry:
  br label %loop

loop:
  %iv = phi i32 [ 0, %entry ], [ %iv.next, %loop ]
  %red = phi i32 [ %start , %entry ], [ %red.next, %loop ]
  %red.next = xor i32 %red, 3
  %iv.next = add i32 %iv, 1
  %ec = icmp eq i32 %iv, 5
  br i1 %ec, label %exit, label %loop

exit:
  ret i32 %red.next
}

attributes #0 = { vscale_range(2,2) }