llvm/test/Transforms/LoopVectorize/outer-loop-merge-predecessors.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --check-globals none --version 6
; RUN: opt -passes=loop-vectorize -enable-vplan-native-path -S %s | FileCheck %s

define void @outer_loop_with_inner_block_chain(ptr noalias %dst, ptr noalias %src, i64 %n, i64 %m) {
; CHECK-LABEL: define void @outer_loop_with_inner_block_chain(
; CHECK-SAME: ptr noalias [[DST:%.*]], ptr noalias [[SRC:%.*]], i64 [[N:%.*]], i64 [[M:%.*]]) {
; CHECK-NEXT:  [[ENTRY:.*]]:
; CHECK-NEXT:    [[MIN_ITERS_CHECK:%.*]] = icmp ult i64 [[N]], 4
; CHECK-NEXT:    br i1 [[MIN_ITERS_CHECK]], label %[[SCALAR_PH:.*]], label %[[VECTOR_PH:.*]]
; CHECK:       [[VECTOR_PH]]:
; CHECK-NEXT:    [[TMP0:%.*]] = and i64 [[N]], 3
; CHECK-NEXT:    [[N_VEC:%.*]] = sub i64 [[N]], [[TMP0]]
; CHECK-NEXT:    [[BROADCAST_SPLATINSERT:%.*]] = insertelement <4 x i64> poison, i64 [[N]], i64 0
; CHECK-NEXT:    [[BROADCAST_SPLAT:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT]], <4 x i64> poison, <4 x i32> zeroinitializer
; CHECK-NEXT:    [[BROADCAST_SPLATINSERT1:%.*]] = insertelement <4 x i64> poison, i64 [[M]], i64 0
; CHECK-NEXT:    [[BROADCAST_SPLAT2:%.*]] = shufflevector <4 x i64> [[BROADCAST_SPLATINSERT1]], <4 x i64> poison, <4 x i32> zeroinitializer
; CHECK-NEXT:    br label %[[VECTOR_BODY:.*]]
; CHECK:       [[VECTOR_BODY]]:
; CHECK-NEXT:    [[INDEX:%.*]] = phi i64 [ 0, %[[VECTOR_PH]] ], [ [[INDEX_NEXT:%.*]], %[[OUTER_LATCH6:.*]] ]
; CHECK-NEXT:    [[VEC_IND:%.*]] = phi <4 x i64> [ <i64 0, i64 1, i64 2, i64 3>, %[[VECTOR_PH]] ], [ [[VEC_IND_NEXT:%.*]], %[[OUTER_LATCH6]] ]
; CHECK-NEXT:    br label %[[INNER_HEADER3:.*]]
; CHECK:       [[INNER_HEADER3]]:
; CHECK-NEXT:    [[INNER_IV4:%.*]] = phi <4 x i64> [ zeroinitializer, %[[VECTOR_BODY]] ], [ [[TMP4:%.*]], %[[INNER_HEADER3]] ]
; CHECK-NEXT:    [[SUM5:%.*]] = phi <4 x i32> [ zeroinitializer, %[[VECTOR_BODY]] ], [ [[TMP3:%.*]], %[[INNER_HEADER3]] ]
; CHECK-NEXT:    [[TMP1:%.*]] = mul <4 x i64> [[INNER_IV4]], [[BROADCAST_SPLAT]]
; CHECK-NEXT:    [[TMP2:%.*]] = add <4 x i64> [[TMP1]], [[VEC_IND]]
; CHECK-NEXT:    [[WIDE_GEP:%.*]] = getelementptr inbounds i32, ptr [[SRC]], <4 x i64> [[TMP2]]
; CHECK-NEXT:    [[WIDE_MASKED_GATHER:%.*]] = call <4 x i32> @llvm.masked.gather.v4i32.v4p0(<4 x ptr> align 4 [[WIDE_GEP]], <4 x i1> splat (i1 true), <4 x i32> poison)
; CHECK-NEXT:    [[TMP3]] = add <4 x i32> [[SUM5]], [[WIDE_MASKED_GATHER]]
; CHECK-NEXT:    [[TMP4]] = add nuw nsw <4 x i64> [[INNER_IV4]], splat (i64 1)
; CHECK-NEXT:    [[TMP5:%.*]] = icmp eq <4 x i64> [[TMP4]], [[BROADCAST_SPLAT2]]
; CHECK-NEXT:    [[TMP6:%.*]] = extractelement <4 x i1> [[TMP5]], i64 0
; CHECK-NEXT:    br i1 [[TMP6]], label %[[OUTER_LATCH6]], label %[[INNER_HEADER3]]
; CHECK:       [[OUTER_LATCH6]]:
; CHECK-NEXT:    [[TMP7:%.*]] = getelementptr inbounds i32, ptr [[DST]], i64 [[INDEX]]
; CHECK-NEXT:    store <4 x i32> [[TMP3]], ptr [[TMP7]], align 4
; CHECK-NEXT:    [[INDEX_NEXT]] = add nuw i64 [[INDEX]], 4
; CHECK-NEXT:    [[VEC_IND_NEXT]] = add nuw nsw <4 x i64> [[VEC_IND]], splat (i64 4)
; CHECK-NEXT:    [[TMP8:%.*]] = icmp eq i64 [[INDEX_NEXT]], [[N_VEC]]
; CHECK-NEXT:    br i1 [[TMP8]], label %[[MIDDLE_BLOCK:.*]], label %[[VECTOR_BODY]], !llvm.loop [[LOOP0:![0-9]+]]
; CHECK:       [[MIDDLE_BLOCK]]:
; CHECK-NEXT:    [[CMP_N:%.*]] = icmp eq i64 [[N]], [[N_VEC]]
; CHECK-NEXT:    br i1 [[CMP_N]], label %[[EXIT:.*]], label %[[SCALAR_PH]]
; CHECK:       [[SCALAR_PH]]:
; CHECK-NEXT:    [[BC_RESUME_VAL:%.*]] = phi i64 [ [[N_VEC]], %[[MIDDLE_BLOCK]] ], [ 0, %[[ENTRY]] ]
; CHECK-NEXT:    br label %[[OUTER_HEADER:.*]]
; CHECK:       [[OUTER_HEADER]]:
; CHECK-NEXT:    [[OUTER_IV:%.*]] = phi i64 [ [[BC_RESUME_VAL]], %[[SCALAR_PH]] ], [ [[OUTER_IV_NEXT:%.*]], %[[OUTER_LATCH:.*]] ]
; CHECK-NEXT:    br label %[[INNER_HEADER:.*]]
; CHECK:       [[INNER_HEADER]]:
; CHECK-NEXT:    [[INNER_IV:%.*]] = phi i64 [ 0, %[[OUTER_HEADER]] ], [ [[INNER_IV_NEXT:%.*]], %[[INNER_LATCH:.*]] ]
; CHECK-NEXT:    [[SUM:%.*]] = phi i32 [ 0, %[[OUTER_HEADER]] ], [ [[SUM_NEXT:%.*]], %[[INNER_LATCH]] ]
; CHECK-NEXT:    [[ROW_OFFSET:%.*]] = mul i64 [[INNER_IV]], [[N]]
; CHECK-NEXT:    [[OFFSET:%.*]] = add i64 [[ROW_OFFSET]], [[OUTER_IV]]
; CHECK-NEXT:    [[GEP_SRC:%.*]] = getelementptr inbounds i32, ptr [[SRC]], i64 [[OFFSET]]
; CHECK-NEXT:    br label %[[INNER_BODY:.*]]
; CHECK:       [[INNER_BODY]]:
; CHECK-NEXT:    [[L:%.*]] = load i32, ptr [[GEP_SRC]], align 4
; CHECK-NEXT:    [[SUM_NEXT]] = add i32 [[SUM]], [[L]]
; CHECK-NEXT:    br label %[[INNER_LATCH]]
; CHECK:       [[INNER_LATCH]]:
; CHECK-NEXT:    [[INNER_IV_NEXT]] = add nuw nsw i64 [[INNER_IV]], 1
; CHECK-NEXT:    [[INNER_EC:%.*]] = icmp eq i64 [[INNER_IV_NEXT]], [[M]]
; CHECK-NEXT:    br i1 [[INNER_EC]], label %[[OUTER_LATCH]], label %[[INNER_HEADER]]
; CHECK:       [[OUTER_LATCH]]:
; CHECK-NEXT:    [[SUM_NEXT_LCSSA:%.*]] = phi i32 [ [[SUM_NEXT]], %[[INNER_LATCH]] ]
; CHECK-NEXT:    [[GEP_DST:%.*]] = getelementptr inbounds i32, ptr [[DST]], i64 [[OUTER_IV]]
; CHECK-NEXT:    store i32 [[SUM_NEXT_LCSSA]], ptr [[GEP_DST]], align 4
; CHECK-NEXT:    [[OUTER_IV_NEXT]] = add nuw nsw i64 [[OUTER_IV]], 1
; CHECK-NEXT:    [[OUTER_EC:%.*]] = icmp eq i64 [[OUTER_IV_NEXT]], [[N]]
; CHECK-NEXT:    br i1 [[OUTER_EC]], label %[[EXIT]], label %[[OUTER_HEADER]], !llvm.loop [[LOOP3:![0-9]+]]
; CHECK:       [[EXIT]]:
; CHECK-NEXT:    ret void
;
entry:
  br label %outer.header

outer.header:
  %outer.iv = phi i64 [ 0, %entry ], [ %outer.iv.next, %outer.latch ]
  br label %inner.header

inner.header:
  %inner.iv = phi i64 [ 0, %outer.header ], [ %inner.iv.next, %inner.latch ]
  %sum = phi i32 [ 0, %outer.header ], [ %sum.next, %inner.latch ]
  %row.offset = mul i64 %inner.iv, %n
  %offset = add i64 %row.offset, %outer.iv
  %gep.src = getelementptr inbounds i32, ptr %src, i64 %offset
  br label %inner.body

inner.body:
  %l = load i32, ptr %gep.src, align 4
  %sum.next = add i32 %sum, %l
  br label %inner.latch

inner.latch:
  %inner.iv.next = add nuw nsw i64 %inner.iv, 1
  %inner.ec = icmp eq i64 %inner.iv.next, %m
  br i1 %inner.ec, label %outer.latch, label %inner.header

outer.latch:
  %gep.dst = getelementptr inbounds i32, ptr %dst, i64 %outer.iv
  store i32 %sum.next, ptr %gep.dst, align 4
  %outer.iv.next = add nuw nsw i64 %outer.iv, 1
  %outer.ec = icmp eq i64 %outer.iv.next, %n
  br i1 %outer.ec, label %exit, label %outer.header, !llvm.loop !0

exit:
  ret void
}

!0 = distinct !{!0, !1, !2}
!1 = !{!"llvm.loop.vectorize.enable"}
!2 = !{!"llvm.loop.vectorize.width", i32 4}