; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -fix-irreducible -structurizecfg -S | FileCheck %s
; Both B1 and B4 are headers of an irreducible cycle. But in the
; structurized version, B1 dominates B4. The program is structurized
; correctly when the irreducible cycle is fixed.
define void @irreducible(i1 %PredEntry, i1 %PredB1, i1 %PredB2, i1 %PredB3, i1 %PredB4)
; CHECK-LABEL: @irreducible(
; CHECK-NEXT: entry:
; CHECK-NEXT: [[PREDB2_INV:%.*]] = xor i1 [[PREDB2:%.*]], true
; CHECK-NEXT: [[PREDENTRY_INV:%.*]] = xor i1 [[PREDENTRY:%.*]], true
; CHECK-NEXT: br label [[IRR_GUARD:%.*]]
; CHECK: Flow4:
; CHECK-NEXT: [[TMP0:%.*]] = phi i1 [ true, [[B3:%.*]] ], [ undef, [[B2:%.*]] ]
; CHECK-NEXT: [[TMP1:%.*]] = phi i1 [ [[PREDB3:%.*]], [[B3]] ], [ true, [[B2]] ]
; CHECK-NEXT: [[TMP2:%.*]] = phi i1 [ [[PREDB3]], [[B3]] ], [ false, [[B2]] ]
; CHECK-NEXT: br label [[FLOW3:%.*]]
; CHECK: B1:
; CHECK-NEXT: br label [[FLOW5:%.*]]
; CHECK: Flow2:
; CHECK-NEXT: [[TMP3:%.*]] = phi i1 [ [[TMP9:%.*]], [[FLOW5]] ], [ [[TMP11:%.*]], [[FLOW:%.*]] ]
; CHECK-NEXT: [[TMP4:%.*]] = phi i1 [ [[TMP10:%.*]], [[FLOW5]] ], [ [[TMP12:%.*]], [[FLOW]] ]
; CHECK-NEXT: [[TMP5:%.*]] = phi i1 [ [[TMP7:%.*]], [[FLOW5]] ], [ true, [[FLOW]] ]
; CHECK-NEXT: br i1 true, label [[FLOW6:%.*]], label [[FLOW]]
; CHECK: B2:
; CHECK-NEXT: br i1 [[PREDB2_INV]], label [[B3]], label [[FLOW4:%.*]]
; CHECK: Flow3:
; CHECK-NEXT: [[TMP6:%.*]] = phi i1 [ [[TMP0]], [[FLOW4]] ], [ undef, [[IRR_GUARD1:%.*]] ]
; CHECK-NEXT: [[TMP7]] = phi i1 [ [[TMP1]], [[FLOW4]] ], [ true, [[IRR_GUARD1]] ]
; CHECK-NEXT: [[TMP8:%.*]] = phi i1 [ [[TMP2]], [[FLOW4]] ], [ true, [[IRR_GUARD1]] ]
; CHECK-NEXT: br i1 [[TMP8]], label [[B1:%.*]], label [[FLOW5]]
; CHECK: B3:
; CHECK-NEXT: br label [[FLOW4]]
; CHECK: B4:
; CHECK-NEXT: br label [[FLOW]]
; CHECK: Flow5:
; CHECK-NEXT: [[TMP9]] = phi i1 [ undef, [[B1]] ], [ [[TMP6]], [[FLOW3]] ]
; CHECK-NEXT: [[TMP10]] = phi i1 [ true, [[B1]] ], [ undef, [[FLOW3]] ]
; CHECK-NEXT: br label [[FLOW2:%.*]]
; CHECK: Flow6:
; CHECK-NEXT: br i1 [[TMP5]], label [[EXIT:%.*]], label [[IRR_GUARD]]
; CHECK: exit:
; CHECK-NEXT: ret void
; CHECK: irr.guard:
; CHECK-NEXT: [[GUARD_B4:%.*]] = phi i1 [ [[PREDENTRY_INV]], [[ENTRY:%.*]] ], [ [[TMP3]], [[FLOW6]] ]
; CHECK-NEXT: br i1 [[GUARD_B4]], label [[B4:%.*]], label [[FLOW]]
; CHECK: Flow:
; CHECK-NEXT: [[TMP11]] = phi i1 [ [[TMP3]], [[FLOW2]] ], [ undef, [[B4]] ], [ undef, [[IRR_GUARD]] ]
; CHECK-NEXT: [[TMP12]] = phi i1 [ [[TMP4]], [[FLOW2]] ], [ true, [[B4]] ], [ false, [[IRR_GUARD]] ]
; CHECK-NEXT: [[TMP13:%.*]] = phi i1 [ false, [[FLOW2]] ], [ [[PREDB4:%.*]], [[B4]] ], [ true, [[IRR_GUARD]] ]
; CHECK-NEXT: br i1 [[TMP13]], label [[IRR_GUARD1]], label [[FLOW2]]
; CHECK: irr.guard1:
; CHECK-NEXT: br i1 [[TMP12]], label [[B2]], label [[FLOW3]]
;
{
entry:
br i1 %PredEntry, label %B1, label %B4
B1:
br i1 %PredB1, label %exit, label %B2
B2:
br i1 %PredB2, label %exit, label %B3
B3:
br i1 %PredB3, label %B1, label %B4
B4:
br i1 %PredB4, label %B2, label %exit
exit:
ret void
}
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