llvm/test/Transforms/LoopUnroll/partial-unroll-non-latch-exit.ll

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt -S -passes=loop-unroll -unroll-allow-partial %s | FileCheck %s

; This is a variant on full-unroll-non-latch-exit.ll for partial unrolling.
; This test is primarily interested in making sure that latches are not
; folded incorrectly, not that a transform occurs.

define i1 @test(ptr %a1, ptr %a2) {
; CHECK-LABEL: @test(
; CHECK-NEXT:  start:
; CHECK-NEXT:    br label [[LOOP:%.*]]
; CHECK:       loop:
; CHECK-NEXT:    [[IV:%.*]] = phi i64 [ 0, [[START:%.*]] ], [ [[IV_NEXT_4:%.*]], [[LATCH_4:%.*]] ]
; CHECK-NEXT:    br label [[LATCH:%.*]]
; CHECK:       latch:
; CHECK-NEXT:    [[IV_NEXT:%.*]] = add nuw nsw i64 [[IV]], 1
; CHECK-NEXT:    [[GEP1:%.*]] = getelementptr inbounds i64, ptr [[A1:%.*]], i64 [[IV]]
; CHECK-NEXT:    [[GEP2:%.*]] = getelementptr inbounds i64, ptr [[A2:%.*]], i64 [[IV]]
; CHECK-NEXT:    [[LOAD1:%.*]] = load i64, ptr [[GEP1]], align 8
; CHECK-NEXT:    [[LOAD2:%.*]] = load i64, ptr [[GEP2]], align 8
; CHECK-NEXT:    [[EXITCOND2:%.*]] = icmp eq i64 [[LOAD1]], [[LOAD2]]
; CHECK-NEXT:    br i1 [[EXITCOND2]], label [[LOOP_1:%.*]], label [[EXIT:%.*]]
; CHECK:       loop.1:
; CHECK-NEXT:    br label [[LATCH_1:%.*]]
; CHECK:       latch.1:
; CHECK-NEXT:    [[IV_NEXT_1:%.*]] = add nuw nsw i64 [[IV]], 2
; CHECK-NEXT:    [[GEP1_1:%.*]] = getelementptr inbounds i64, ptr [[A1]], i64 [[IV_NEXT]]
; CHECK-NEXT:    [[GEP2_1:%.*]] = getelementptr inbounds i64, ptr [[A2]], i64 [[IV_NEXT]]
; CHECK-NEXT:    [[LOAD1_1:%.*]] = load i64, ptr [[GEP1_1]], align 8
; CHECK-NEXT:    [[LOAD2_1:%.*]] = load i64, ptr [[GEP2_1]], align 8
; CHECK-NEXT:    [[EXITCOND2_1:%.*]] = icmp eq i64 [[LOAD1_1]], [[LOAD2_1]]
; CHECK-NEXT:    br i1 [[EXITCOND2_1]], label [[LOOP_2:%.*]], label [[EXIT]]
; CHECK:       loop.2:
; CHECK-NEXT:    br label [[LATCH_2:%.*]]
; CHECK:       latch.2:
; CHECK-NEXT:    [[IV_NEXT_2:%.*]] = add nuw nsw i64 [[IV]], 3
; CHECK-NEXT:    [[GEP1_2:%.*]] = getelementptr inbounds i64, ptr [[A1]], i64 [[IV_NEXT_1]]
; CHECK-NEXT:    [[GEP2_2:%.*]] = getelementptr inbounds i64, ptr [[A2]], i64 [[IV_NEXT_1]]
; CHECK-NEXT:    [[LOAD1_2:%.*]] = load i64, ptr [[GEP1_2]], align 8
; CHECK-NEXT:    [[LOAD2_2:%.*]] = load i64, ptr [[GEP2_2]], align 8
; CHECK-NEXT:    [[EXITCOND2_2:%.*]] = icmp eq i64 [[LOAD1_2]], [[LOAD2_2]]
; CHECK-NEXT:    br i1 [[EXITCOND2_2]], label [[LOOP_3:%.*]], label [[EXIT]]
; CHECK:       loop.3:
; CHECK-NEXT:    br label [[LATCH_3:%.*]]
; CHECK:       latch.3:
; CHECK-NEXT:    [[IV_NEXT_3:%.*]] = add nuw nsw i64 [[IV]], 4
; CHECK-NEXT:    [[GEP1_3:%.*]] = getelementptr inbounds i64, ptr [[A1]], i64 [[IV_NEXT_2]]
; CHECK-NEXT:    [[GEP2_3:%.*]] = getelementptr inbounds i64, ptr [[A2]], i64 [[IV_NEXT_2]]
; CHECK-NEXT:    [[LOAD1_3:%.*]] = load i64, ptr [[GEP1_3]], align 8
; CHECK-NEXT:    [[LOAD2_3:%.*]] = load i64, ptr [[GEP2_3]], align 8
; CHECK-NEXT:    [[EXITCOND2_3:%.*]] = icmp eq i64 [[LOAD1_3]], [[LOAD2_3]]
; CHECK-NEXT:    br i1 [[EXITCOND2_3]], label [[LOOP_4:%.*]], label [[EXIT]]
; CHECK:       loop.4:
; CHECK-NEXT:    [[EXITCOND_4:%.*]] = icmp eq i64 [[IV_NEXT_3]], 24
; CHECK-NEXT:    br i1 [[EXITCOND_4]], label [[EXIT]], label [[LATCH_4]]
; CHECK:       latch.4:
; CHECK-NEXT:    [[IV_NEXT_4]] = add nuw nsw i64 [[IV]], 5
; CHECK-NEXT:    [[GEP1_4:%.*]] = getelementptr inbounds i64, ptr [[A1]], i64 [[IV_NEXT_3]]
; CHECK-NEXT:    [[GEP2_4:%.*]] = getelementptr inbounds i64, ptr [[A2]], i64 [[IV_NEXT_3]]
; CHECK-NEXT:    [[LOAD1_4:%.*]] = load i64, ptr [[GEP1_4]], align 8
; CHECK-NEXT:    [[LOAD2_4:%.*]] = load i64, ptr [[GEP2_4]], align 8
; CHECK-NEXT:    [[EXITCOND2_4:%.*]] = icmp eq i64 [[LOAD1_4]], [[LOAD2_4]]
; CHECK-NEXT:    br i1 [[EXITCOND2_4]], label [[LOOP]], label [[EXIT]]
; CHECK:       exit:
; CHECK-NEXT:    [[EXIT_VAL:%.*]] = phi i1 [ false, [[LATCH]] ], [ false, [[LATCH_1]] ], [ false, [[LATCH_2]] ], [ false, [[LATCH_3]] ], [ true, [[LOOP_4]] ], [ false, [[LATCH_4]] ]
; CHECK-NEXT:    ret i1 [[EXIT_VAL]]
;
start:
  br label %loop

loop:
  %iv = phi i64 [ 0, %start ], [ %iv.next, %latch ]
  %exitcond = icmp eq i64 %iv, 24
  br i1 %exitcond, label %exit, label %latch

latch:
  %iv.next = add nuw nsw i64 %iv, 1
  %gep1 = getelementptr inbounds i64, ptr %a1, i64 %iv
  %gep2 = getelementptr inbounds i64, ptr %a2, i64 %iv
  %load1 = load i64, ptr %gep1, align 8
  %load2 = load i64, ptr %gep2, align 8
  %exitcond2 = icmp eq i64 %load1, %load2
  br i1 %exitcond2, label %loop, label %exit

exit:
  %exit.val = phi i1 [ false, %latch ], [ true, %loop ]
  ret i1 %exit.val
}