// RUN: %target-sil-opt -enable-sil-verify-all -compute-dominance-info -compute-loop-info -loop-canonicalizer %s | %FileCheck %s

sil_stage canonical

import Builtin

// Test insertBackedgeBlock.
//
// CHECK-LABEL: insert_backedge_block
// CHECK: bb2:
// CHECK: cond_br undef, bb3, bb5
// CHECK: bb3:
// CHECK: br bb4
// CHECK: bb5:
// CHECK: cond_br undef, bb6, bb7
// CHECK: bb6:
// CHECK: br bb4
sil @insert_backedge_block : $@convention(thin) () -> () {
bb0:
  br bb1

bb1:
  br bb2

bb2:
  cond_br undef, bb3, bb4

bb3:
  br bb1

bb4:
  cond_br undef, bb5, bb7

bb5:
  br bb1

bb7:
  return undef : $()
}

// CHECK-LABEL: sil @insert_backedge_block_inner_loop : $@convention(thin) () -> () {
// CHECK: bb1:
// CHECK: br bb2
// CHECK: bb2:
// CHECK: br bb3
// CHECK: bb3:
// CHECK: cond_br undef, bb4, bb6
// CHECK: bb4:
// CHECK: br bb5
// CHECK: bb5:
// CHECK: br bb2
// CHECK: bb6:
// CHECK: cond_br undef, bb7, bb8
// CHECK: bb7:
// CHECK: br bb5
// CHECK: bb8:
// CHECK: cond_br undef, bb9, bb10
// CHECK: bb9:
// CHECK: br bb1
// CHECK: bb10:
// CHECK: return undef
sil @insert_backedge_block_inner_loop : $@convention(thin) () -> () {
bb0:
  br bb1

bb1:
  br bb2

bb2:
  br bb3

bb3:
  cond_br undef, bb4, bb5

bb4:
  br bb2

bb5:
  cond_br undef, bb6, bb7

bb6:
  br bb2

bb7:
  cond_br undef, bb8, bb9

bb8:
  br bb1

bb9:
  return undef : $()
}