allocbox_to_stack.sil

// RUN: %target-sil-opt -assume-parsing-unqualified-ownership-sil -enable-sil-verify-all %s -allocbox-to-stack | %FileCheck %s

import Builtin

struct Int {
  var _value: Builtin.Int64
}

struct Bool {
  var _value: Builtin.Int1
}

protocol Error {}

// CHECK-LABEL: sil @simple_promotion
sil @simple_promotion : $(Int) -> Int {
bb0(%0 : $Int):
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  %2 = store %0 to %1a : $*Int
  %3 = load %1a : $*Int
  %4 = strong_release %1 : ${ var Int }
  %5 = return %3 : $Int

// CHECK: alloc_stack
// CHECK-NOT: alloc_box
// CHECK-NOT: strong_release
// CHECK: return
}

// CHECK-LABEL: sil @double_project_box
sil @double_project_box : $(Int) -> (Int, Int) {
bb0(%0 : $Int):
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  %2 = store %0 to %1a : $*Int
  %3 = load %1a : $*Int
  %1b = project_box %1 : ${ var Int }, 0
  %3b = load %1b : $*Int
  %4 = strong_release %1 : ${ var Int }
  %r = tuple (%3 : $Int, %3b : $Int)
  %5 = return %r : $(Int, Int)

// CHECK: alloc_stack
// CHECK-NOT: alloc_box
// CHECK-NOT: project_box
// CHECK-NOT: strong_release
// CHECK: return
}
// CHECK-LABEL: sil @init_var
sil @init_var : $() -> Int {
bb0:
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  %3 = load %1a : $*Int
  %4 = strong_release %1 : ${ var Int }
  %5 = return %3 : $Int

// CHECK: %0 = alloc_stack
// CHECK-NOT: alloc_box
// CHECK-NOT: strong_release
// CHECK-NOT: destroy_addr
// CHECK: dealloc_stack %0 : $*Int
// CHECK: return
}

// CHECK-LABEL: sil @multi_strong_release
sil @multi_strong_release : $() -> Int {
bb0:
  %1 = alloc_box ${ var Int }
  %1a = mark_uninitialized [rootself] %1 : ${ var Int }
  %2 = project_box %1a : ${ var Int }, 0
  %3 = load %2 : $*Int
  %x = strong_retain %1a : ${ var Int }
  %y = strong_release %1a : ${ var Int }
  %b = br bb1
bb1:

  %4 = strong_release %1a : ${ var Int }
  %5 = return %3 : $Int

// CHECK: %0 = alloc_stack
// CHECK: bb1:
// CHECK: dealloc_stack %0 : $*Int
// CHECK: return
}

struct TestStruct {
  var Elt : Int
}

// CHECK-LABEL: sil @struct_tuple_element_addr
sil @struct_tuple_element_addr : $(Int) -> Int {
bb1(%0 : $Int):
// CHECK-DAG: [[STRUCT:%.*]] = alloc_stack $TestStruct
// CHECK-DAG: [[TUPLE:%.*]] = alloc_stack $(Int, Int)
  %1 = alloc_box ${ var TestStruct }
  %1a = project_box %1 : ${ var TestStruct }, 0
  %a = alloc_box ${ var (Int, Int) }
  %aa = project_box %a : ${ var (Int, Int) }, 0

  %2 = struct_element_addr %1a : $*TestStruct, #TestStruct.Elt
  %3 = store %0 to %2 : $*Int

  %b = tuple_element_addr %aa : $*(Int, Int), 0
  %c = store %0 to %b : $*Int

  %6 = struct_element_addr %1a : $*TestStruct, #TestStruct.Elt
  %7 = load %6 : $*Int
  %x = strong_release %a : ${ var (Int, Int) }
  %8 = strong_release %1 : ${ var TestStruct }


  %9 = return %7 : $Int

// CHECK-DAG: dealloc_stack [[STRUCT]]
// CHECK-DAG: dealloc_stack [[TUPLE]]
// CHECK: return
}




sil @callee : $@convention(thin) (@inout Int) -> ()

// CHECK-LABEL: sil @inout_nocapture
sil @inout_nocapture : $@convention(thin) () -> Int {
bb0:
  // CHECK: alloc_stack
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  %6 = function_ref @callee : $@convention(thin) (@inout Int) -> ()
  %7 = apply %6(%1a) : $@convention(thin) (@inout Int) -> ()
  %8 = load %1a : $*Int
  %9 = strong_release %1 : ${ var Int }
  %10 = address_to_pointer %1a : $*Int to $Builtin.RawPointer
  %11 = pointer_to_address %10 : $Builtin.RawPointer to [strict] $*Int
  %12 = load %11 : $*Int
  %13 = return %8 : $Int
  // CHECK: return
}


protocol P {
}

sil @returns_protocol : $@convention(thin) () -> @out P

// CHECK-LABEL: sil @test_indirect_return
sil @test_indirect_return : $@convention(thin) () -> () {
bb0:
  // CHECK: alloc_stack
  %1 = function_ref @returns_protocol : $@convention(thin) () -> @out P
  %2 = alloc_box ${ var P }
  %2a = project_box %2 : ${ var P }, 0
  %3 = apply %1(%2a) : $@convention(thin) () -> @out P
  %5 = strong_release %2 : ${ var P }
  %0 = tuple ()
  %6 = return %0 : $()
  // CHECK: return
}

class SomeClass {}

// CHECK-LABEL: sil @class_promotion
sil @class_promotion : $(SomeClass) -> SomeClass {
bb0(%0 : $SomeClass):
  %1 = alloc_box ${ var SomeClass }
  %1a = project_box %1 : ${ var SomeClass }, 0
  %2 = store %0 to %1a : $*SomeClass
  %3 = load %1a : $*SomeClass
  %4 = strong_release %1 : ${ var SomeClass }
  %5 = return %3 : $SomeClass

// CHECK: %1 = alloc_stack
// CHECK-NOT: alloc_box
// CHECK-NOT: strong_release
// CHECK: destroy_addr {{.*}} : $*SomeClass
// CHECK: return
}

protocol LogicValue {
  func getLogicValue() -> Bool
}

// CHECK-LABEL: @protocols
sil @protocols : $@convention(thin) (@in LogicValue, @thin Bool.Type) -> Bool {
bb0(%0 : $*LogicValue, %1 : $@thin Bool.Type):
  %2 = alloc_box ${ var LogicValue }
  %2a = project_box %2 : ${ var LogicValue }, 0
// CHECK:  %2 = alloc_stack $LogicValue
  copy_addr [take] %0 to [initialization] %2a : $*LogicValue
  %6 = open_existential_addr mutable_access %2a : $*LogicValue to $*@opened("01234567-89ab-cdef-0123-000000000000") LogicValue
  %7 = witness_method $@opened("01234567-89ab-cdef-0123-000000000000") LogicValue, #LogicValue.getLogicValue!1, %6 : $*@opened("01234567-89ab-cdef-0123-000000000000") LogicValue : $@convention(witness_method) <T: LogicValue> (@in_guaranteed T) -> Bool
  %8 = apply %7<@opened("01234567-89ab-cdef-0123-000000000000") LogicValue>(%6) : $@convention(witness_method) <T: LogicValue> (@in_guaranteed T) -> Bool
  strong_release %2 : ${ var LogicValue }
// CHECK:  destroy_addr %2 : $*LogicValue
// CHECK-NEXT:  dealloc_stack %2 : $*LogicValue
// CHECK-NEXT:  return
  return %8 : $Bool
}


// Generics test, which is address-only.
class Generic<T> {}

// CHECK-LABEL: sil @dealloc_box
sil @dealloc_box : $@convention(thin) <T> () -> () {
bb0:  // CHECK-NEXT: bb0:
      // CHECK-NEXT: alloc_stack
  %1 = alloc_box $<τ_0_0> { var Generic<τ_0_0> } <T>
  dealloc_box %1 : $<τ_0_0> { var Generic<τ_0_0> } <T>

  %0 = tuple ()    // CHECK: tuple ()
  %6 = return %0 : $()
  // CHECK: return
}


enum SomeUnion {
  case x(Int)
  case y(SomeClass)
}



sil @_T01t9SomeUnionO1yfMS0_FCS_9SomeClassS0_ : $@convention(thin) (@owned SomeClass, @thin SomeUnion.Type) -> @owned SomeUnion
sil @_T01t9SomeClassCCfMS0_FT_S0_ : $@convention(thin) (@thick SomeClass.Type) -> @owned SomeClass

// CHECK-LABEL: sil @union_test
sil @union_test : $@convention(thin) () -> () {
bb0:
// CHECK: [[UNION:%.*]] = alloc_stack
  %1 = alloc_box ${ var SomeUnion }
  %1a = project_box %1 : ${ var SomeUnion }, 0
  %2 = function_ref @_T01t9SomeUnionO1yfMS0_FCS_9SomeClassS0_ : $@convention(thin) (@owned SomeClass, @thin SomeUnion.Type) -> @owned SomeUnion // user: %7
  %3 = metatype $@thin SomeUnion.Type
  %4 = function_ref @_T01t9SomeClassCCfMS0_FT_S0_ : $@convention(thin) (@thick SomeClass.Type) -> @owned SomeClass // user: %6
  %5 = metatype $@thick SomeClass.Type
  %6 = apply %4(%5) : $@convention(thin) (@thick SomeClass.Type) -> @owned SomeClass
  %7 = apply %2(%6, %3) : $@convention(thin) (@owned SomeClass, @thin SomeUnion.Type) -> @owned SomeUnion
  store %7 to %1a : $*SomeUnion
  strong_release %1 : ${ var SomeUnion }
  %10 = tuple ()
  return %10 : $()
// CHECK: dealloc_stack [[UNION]]
// CHECK:  [[T0:%.*]] = tuple ()
// CHECK-NEXT:  return [[T0]] : $()
}

// CHECK-LABEL: sil @multiple_release_test
sil @multiple_release_test : $@convention(thin) (Bool) -> Bool {
bb0(%0 : $Bool):
  %1 = alloc_box ${ var Bool }
  %1a = project_box %1 : ${ var Bool }, 0
  store %0 to %1a : $*Bool
  strong_retain %1 : ${ var Bool }
  strong_retain %1 : ${ var Bool }
  %5 = tuple ()
  %6 = load %1a : $*Bool
  strong_release %1 : ${ var Bool }
  strong_release %1 : ${ var Bool }
  strong_release %1 : ${ var Bool }
  return %6 : $Bool

  // CHECK: alloc_stack $Bool
  // CHECK-NEXT: store
  // CHECK-NEXT: tuple ()
  // CHECK-NEXT: load
  // CHECK-NEXT: dealloc_stack
  // CHECK-NEXT: return
}

// Make sure that we can promote this box and dealloc_stack
// on each path.
//
// CHECK-LABEL: sil @box_reachable_from_release_test
sil @box_reachable_from_release_test : $@convention(thin) () -> () {
bb0:
  br bb1

// CHECK: bb1:
// CHECK-NEXT: alloc_stack
bb1:
  %1 = alloc_box ${ var Bool }
  cond_br undef, bb2, bb3

// CHECK: bb2:
// CHECK-NEXT: dealloc_stack
bb2:
  strong_release %1 : ${ var Bool }
  br bb1

// CHECK: bb3:
// CHECK-NEXT: dealloc_stack
bb3:
  strong_release %1 : ${ var Bool }
  %2 = tuple ()
// CHECK: return
  return %2 : $()
}



sil @useSomeClass : $@convention(thin) (@owned SomeClass) -> ()


// <rdar://problem/16382973> DI misses destroy_addr because allocbox_to_stack isn't preserving mark_uninitialized invariants
// When allocbox_to_stack promotes the box, it should rewrite the multiple
// strong_releases into destroy_addr/dealloc_stack pairs.  However, it needs to
// make sure to use the MUI result for the destroy addr.

public protocol My_Incrementable { }

extension Int : My_Incrementable { }

// CHECK-LABEL: sil @test_mui
sil @test_mui : $@convention(thin) (Builtin.Int1) -> () {
bb0(%0 : $Builtin.Int1):
  %2 = alloc_box ${ var SomeClass }
  %2a = mark_uninitialized [var] %2 : ${ var SomeClass }
  %3 = project_box %2a : ${ var SomeClass }, 0
  // CHECK: [[STACK:%[0-9]+]] = alloc_stack
  // CHECK: [[MUI:%[0-9]+]] = mark_uninitialized
  cond_br %0, bb1, bb3

bb1:
  %7 = function_ref @_T01t9SomeClassCCfMS0_FT_S0_ : $@convention(thin) (@thick SomeClass.Type) -> @owned SomeClass // user: %6
  %8 = metatype $@thick SomeClass.Type
  %9 = apply %7(%8) : $@convention(thin) (@thick SomeClass.Type) -> @owned SomeClass

  assign %9 to %3 : $*SomeClass
  %11 = function_ref @useSomeClass : $@convention(thin) (@owned SomeClass) -> ()
  %12 = load %3 : $*SomeClass
  strong_retain %12 : $SomeClass
  %14 = apply %11(%12) : $@convention(thin) (@owned SomeClass) -> ()

  strong_release %2a : ${ var SomeClass }
  // CHECK: destroy_addr [[MUI]]
  // CHECK-NEXT: dealloc_stack [[STACK]]
  br bb2

  // CHECK: bb2
bb2:
  %17 = tuple ()
  // CHECK: return
  return %17 : $()

bb3:
  strong_release %2a : ${ var SomeClass }
  // CHECK: destroy_addr [[MUI]]
  // CHECK-NEXT: dealloc_stack [[STACK]]
  br bb2
}

// CHECK-LABEL: sil @_T06struct5applySiSiyc1f_tF
// struct.apply (f : () -> Swift.Int) -> Swift.Int
sil @_T06struct5applySiSiyc1f_tF : $@convention(thin) (@owned @callee_owned () -> Int) -> Int {
bb0(%0 : $@callee_owned () -> Int):
  debug_value %0 : $@callee_owned () -> Int, let, name "f" // id: %1
  strong_retain %0 : $@callee_owned () -> Int     // id: %2
  %3 = apply %0() : $@callee_owned () -> Int      // user: %5
  strong_release %0 : $@callee_owned () -> Int    // id: %4
  return %3 : $Int                                // id: %5
}

// CHECK-LABEL: sil @_T06struct6escapeSiycSiyc1f_tF
// struct.escape (f : () -> Swift.Int) -> () -> Swift.Int
sil @_T06struct6escapeSiycSiyc1f_tF : $@convention(thin) (@owned @callee_owned () -> Int) -> @owned @callee_owned () -> Int {
bb0(%0 : $@callee_owned () -> Int):
  debug_value %0 : $@callee_owned () -> Int, let, name "f" // id: %1
  return %0 : $@callee_owned () -> Int            // id: %2
}

// CHECK-LABEL: sil @_T06struct8useStackySi1t_tF
// struct.useStack (t : Swift.Int) -> ()
sil @_T06struct8useStackySi1t_tF : $@convention(thin) (Int) -> () {
bb0(%0 : $Int):
  debug_value %0 : $Int, let, name "t" // id: %1
  // CHECK: alloc_stack
  %2 = alloc_box $<τ_0_0> { var τ_0_0 } <Int>, var, name "s"                   // users: %3, %6, %7, %7, %9
  %2a = project_box %2 : $<τ_0_0> { var τ_0_0 } <Int>, 0
  store %0 to %2a : $*Int                        // id: %3
  // function_ref struct.apply (f : () -> Swift.Int) -> Swift.Int
  %4 = function_ref @_T06struct5applySiSiyc1f_tF : $@convention(thin) (@owned @callee_owned () -> Int) -> Int // user: %8
  // CHECK: [[FUNC:%[a-zA-Z0-9]+]] = function_ref @_T06struct8useStackySi1t_tFSiycfU_Tf0s_n
  // function_ref struct.(useStack (t : Swift.Int) -> ()).(closure #1)
  %5 = function_ref @_T06struct8useStackySi1t_tFSiycfU_ : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> Int // user: %7
  strong_retain %2 : $<τ_0_0> { var τ_0_0 } <Int>     // id: %6
  // CHECK: [[PA:%[a-zA-Z0-9]+]] = partial_apply [[FUNC]]
  %7 = partial_apply %5(%2) : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> Int // user: %8
  %8 = apply %4(%7) : $@convention(thin) (@owned @callee_owned () -> Int) -> Int
  strong_release %2 : $<τ_0_0> { var τ_0_0 } <Int>
  %10 = tuple ()                                  // user: %11
  return %10 : $()                                // id: %11
}

// CHECK-LABEL: sil shared @_T06struct8useStackySi1t_tFSiycfU_Tf0s_n
// CHECK-LABEL: sil private @_T06struct8useStackySi1t_tFSiycfU_
// struct.(useStack (t : Swift.Int) -> ()).(closure #1)
sil private @_T06struct8useStackySi1t_tFSiycfU_ : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> Int {
bb0(%0 : $<τ_0_0> { var τ_0_0 } <Int>):
  %1 = project_box %0 : $<τ_0_0> { var τ_0_0 } <Int>, 0
  // function_ref Swift.++ @postfix <A : Swift._Incrementable>(x : @inout A) -> A
  %2 = function_ref @_TFsoP2ppUs14_Incrementable__FT1xRQ__Q_ : $@convention(thin) <τ_0_0 where τ_0_0 : My_Incrementable> (@inout τ_0_0) -> @out τ_0_0 // user: %4
  %3 = alloc_stack $Int                           // users: %4, %5, %6
  %4 = apply %2<Int>(%3, %1) : $@convention(thin) <τ_0_0 where τ_0_0 : My_Incrementable> (@inout τ_0_0) -> @out τ_0_0
  %5 = load %3 : $*Int                          // user: %8
  dealloc_stack %3 : $*Int       // id: %6
  strong_release %0 : $<τ_0_0> { var τ_0_0 } <Int>      // id: %7
  return %5 : $Int                                // id: %8
}

// Swift.++ @postfix <A : Swift._Incrementable>(x : @inout A) -> A
sil [transparent] @_TFsoP2ppUs14_Incrementable__FT1xRQ__Q_ : $@convention(thin) <τ_0_0 where τ_0_0 : My_Incrementable> (@inout τ_0_0) -> @out τ_0_0

// CHECK-LABEL: sil @_T06struct6useBoxySi1t_tF
// struct.useBox (t : Swift.Int) -> ()
sil @_T06struct6useBoxySi1t_tF : $@convention(thin) (Int) -> () {
bb0(%0 : $Int):
  debug_value %0 : $Int, let, name "t" // id: %1
  // CHECK: alloc_box
  %2 = alloc_box $<τ_0_0> { var τ_0_0 } <Int>, var, name "s"                   // users: %3, %6, %7, %7, %10
  %2a = project_box %2 : $<τ_0_0> { var τ_0_0 } <Int>, 0
  store %0 to %2a : $*Int                        // id: %3
  // function_ref struct.escape (f : () -> Swift.Int) -> () -> Swift.Int
  %4 = function_ref @_T06struct6escapeSiycSiyc1f_tF : $@convention(thin) (@owned @callee_owned () -> Int) -> @owned @callee_owned () -> Int // user: %8
  // function_ref struct.(useBox (t : Swift.Int) -> ()).(closure #1)
  %5 = function_ref @_T06struct6useBoxySi1t_tFSiycfU_ : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> Int // user: %7
  strong_retain %2 : $<τ_0_0> { var τ_0_0 } <Int>     // id: %6
  %7 = partial_apply %5(%2) : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> Int // user: %8
  %8 = apply %4(%7) : $@convention(thin) (@owned @callee_owned () -> Int) -> @owned @callee_owned () -> Int // user: %9
  %9 = apply %8() : $@callee_owned () -> Int
  strong_release %2 : $<τ_0_0> { var τ_0_0 } <Int>    // id: %10
  %11 = tuple ()                                  // user: %12
  return %11 : $()                                // id: %12
}

// CHECK-LABEL: sil private @_T06struct6useBoxySi1t_tFSiycfU_
// struct.(useBox (t : Swift.Int) -> ()).(closure #1)
sil private @_T06struct6useBoxySi1t_tFSiycfU_ : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> Int {
bb0(%0 : $<τ_0_0> { var τ_0_0 } <Int>):
  %1 = project_box %0 : $<τ_0_0> { var τ_0_0 } <Int>, 0
  // function_ref Swift.++ @postfix <A : Swift._Incrementable>(x : @inout A) -> A
  %2 = function_ref @_TFsoP2ppUs14_Incrementable__FT1xRQ__Q_ : $@convention(thin) <τ_0_0 where τ_0_0 : My_Incrementable> (@inout τ_0_0) -> @out τ_0_0 // user: %4
  %3 = alloc_stack $Int                           // users: %4, %5, %6
  %4 = apply %2<Int>(%3, %1) : $@convention(thin) <τ_0_0 where τ_0_0 : My_Incrementable> (@inout τ_0_0) -> @out τ_0_0
  %5 = load %3 : $*Int                          // user: %8
  dealloc_stack %3 : $*Int       // id: %6
  strong_release %0 : $<τ_0_0> { var τ_0_0 } <Int>      // id: %7
  return %5 : $Int                                // id: %8
}

// CHECK-LABEL: sil @closure
sil @closure : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> ()

// CHECK-LABEL: sil @no_final_release
sil @no_final_release : $@convention(thin) (Int) -> Bool {
bb0(%0 : $Int):
  %1 = alloc_box $<τ_0_0> { var τ_0_0 } <Int>
  %1a = project_box %1 : $<τ_0_0> { var τ_0_0 } <Int>, 0
  store %0 to %1a : $*Int
  // function_ref main.(newFoo (Swift.Int) -> Swift.Bool).(modify #1) (())()
  %3 = function_ref @closure : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> ()
  strong_retain %1 : $<τ_0_0> { var τ_0_0 } <Int>
  %5 = partial_apply %3(%1) : $@convention(thin) (@owned <τ_0_0> { var τ_0_0 } <Int>) -> ()
  strong_retain %5 : $@callee_owned () -> ()
  %7 = apply %5() : $@callee_owned () -> ()
  strong_release %5 : $@callee_owned () -> ()
  unreachable
}

// CHECK-LABEL: sil [transparent] [serialized] @mightApply : $@convention(thin) <U where U : P> (@owned @callee_owned () -> @out U) -> ()
sil [transparent] [serialized] @mightApply : $@convention(thin) <U where U : P> (@owned @callee_owned () -> @out U) -> () {
// CHECK: bb0
bb0(%0 : $@callee_owned () -> @out U):
  debug_value %0 : $@callee_owned () -> @out U
  strong_retain %0 : $@callee_owned () -> @out U
  %3 = alloc_stack $U
  %4 = apply %0(%3) : $@callee_owned () -> @out U
  destroy_addr %3 : $*U
  dealloc_stack %3 : $*U
  strong_release %0 : $@callee_owned () -> @out U
  %8 = tuple ()
// CHECK: return
  return %8 : $()
}

// CHECK-LABEL: sil @callWithAutoclosure
sil @callWithAutoclosure : $@convention(thin) <T where T : P> (@in T) -> () {
// CHECK: bb0
bb0(%0 : $*T):
  // CHECK: debug_value_addr
  debug_value_addr %0 : $*T
  // CHECK: function_ref @mightApply
  %2 = function_ref @mightApply : $@convention(thin) <τ_0_0 where τ_0_0 : P> (@owned @callee_owned () -> @out τ_0_0) -> ()
  %3 = function_ref @closure_to_specialize : $@convention(thin) <τ_0_0 where τ_0_0 : P> (@owned <τ_0_0> { var τ_0_0 } <τ_0_0>) -> @out τ_0_0
  // CHECK-NOT: alloc_box
  // CHECK: [[STACK:%[0-9a-zA-Z_]+]] = alloc_stack $T
  %4 = alloc_box $<τ_0_0> { var τ_0_0 } <T>
  %4a = project_box %4 : $<τ_0_0> { var τ_0_0 } <T>, 0
  // CHECK: copy_addr %0 to [initialization] [[STACK]] : $*T
  copy_addr %0 to [initialization] %4a : $*T
  // CHECK: [[CLOSURE:%[0-9a-zA-Z]+]] = function_ref @_T021closure_to_specializeTf0ns_n
  // CHECK: partial_apply [[CLOSURE]]<T>([[STACK]])
  %6 = partial_apply %3<T>(%4) : $@convention(thin) <τ_0_0 where τ_0_0 : P> (@owned <τ_0_0> { var τ_0_0 } <τ_0_0>) -> @out τ_0_0
  %7 = apply %2<T>(%6) : $@convention(thin) <τ_0_0 where τ_0_0 : P> (@owned @callee_owned () -> @out τ_0_0) -> ()
  // CHECK: destroy_addr [[STACK]] : $*T
  // CHECK: dealloc_stack [[STACK]] : $*T
  destroy_addr %0 : $*T
  %9 = tuple ()
  // CHECK: return
  return %9 : $()
}

// CHECK-LABEL: sil shared @_T021closure_to_specializeTf0ns_n : $@convention(thin) <T where T : P> (@inout_aliasable T) -> @out T
sil shared @closure_to_specialize : $@convention(thin) <T where T : P> (@owned <τ_0_0> { var τ_0_0 } <T>) -> @out T {
// CHECK: bb0
bb0(%0 : $*T, %1 : $<τ_0_0> { var τ_0_0 } <T>):
  %2 = project_box %1 : $<τ_0_0> { var τ_0_0 } <T>, 0
  // CHECK-NEXT: copy_addr
  copy_addr %2 to [initialization] %0 : $*T
  // CHECK-NOT: strong_release
  strong_release %1 : $<τ_0_0> { var τ_0_0 } <T>
  %5 = tuple ()
  // CHECK: return
  return %5 : $()
}

protocol Count {
  var count: Int { get }
}

struct Q : Count {
  var count: Int { get }
  init()
}

struct S<T : Count> {
  @sil_stored var t: T
  var count: Int { get }
  func test(i: Int) -> Bool
  init(t: T)
}

// CHECK-LABEL: sil [noinline] @inner
sil [noinline] @inner : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool {
// CHECK: bb0
bb0(%0 : $@callee_owned () -> Bool):
  debug_value %0 : $@callee_owned () -> Bool
  strong_retain %0 : $@callee_owned () -> Bool
  %3 = apply %0() : $@callee_owned () -> Bool
  strong_release %0 : $@callee_owned () -> Bool
// CHECK: return
  return %3 : $Bool
}

// CHECK-LABEL: sil [noinline] @outer
sil [noinline] @outer : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool {
// CHECK: bb0
bb0(%0 : $@callee_owned () -> Bool):
  debug_value %0 : $@callee_owned () -> Bool
  strong_retain %0 : $@callee_owned () -> Bool
  %3 = apply %0() : $@callee_owned () -> Bool
  strong_release %0 : $@callee_owned () -> Bool
// CHECK: return
  return %3 : $Bool
}

// CHECK-LABEL: sil @get
sil @get : $@convention(method) <T where T : Count> (@in S<T>) -> Int

// CHECK-LABEL: sil shared @specialized
sil shared @specialized : $@convention(method) (Int, @in S<Q>) -> Bool {
// CHECK: bb0
bb0(%0 : $Int, %1 : $*S<Q>):
  debug_value %0 : $Int
  debug_value_addr %1 : $*S<Q>
  %4 = function_ref @outer : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool
  %5 = function_ref @closure1 : $@convention(thin) <T where T : Count> (Int, @owned <τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>) -> Bool
  %6 = alloc_box $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <Q>
  %6a = project_box %6 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <Q>, 0
  copy_addr %1 to [initialization] %6a : $*S<Q>
  %8 = partial_apply %5<Q>(%0, %6) : $@convention(thin) <τ_0_0 where τ_0_0 : Count> (Int, @owned <τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <τ_0_0>) -> Bool
  %9 = apply %4(%8) : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool
  destroy_addr %1 : $*S<Q>
// CHECK: return
  return %9 : $Bool
}

// CHECK-LABEL: sil @unspecialized
sil @unspecialized : $@convention(method) <T where T : Count> (Int, @in S<T>) -> Bool {
// CHECK: bb0
bb0(%0 : $Int, %1 : $*S<T>):
  debug_value %0 : $Int
  debug_value_addr %1 : $*S<T>
  %4 = function_ref @outer : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool
  %5 = function_ref @closure1 : $@convention(thin) <τ_0_0 where τ_0_0 : Count> (Int, @owned <τ_0_0 : Count> { var S<τ_0_0> } <τ_0_0>) -> Bool
  %6 = alloc_box $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>
  %6a = project_box %6 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>, 0
  copy_addr %1 to [initialization] %6a : $*S<T>
  %8 = partial_apply %5<T>(%0, %6) : $@convention(thin) <τ_0_0 where τ_0_0 : Count> (Int, @owned <τ_0_0 : Count> { var S<τ_0_0> } <τ_0_0>) -> Bool
  %9 = apply %4(%8) : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool
  destroy_addr %1 : $*S<T>
// CHECK: return
  return %9 : $Bool
}

// CHECK-LABEL: sil shared @closure1
sil shared @closure1 : $@convention(thin) <T where T : Count> (Int, @owned <τ_0_0 : Count> { var S<τ_0_0> } <T>) -> Bool {
// CHECK: bb0
bb0(%0 : $Int, %1 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>):
  %2 = project_box %1 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>, 0
  %3 = function_ref @inner : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool
  %4 = function_ref @closure2 : $@convention(thin) <τ_0_0 where τ_0_0 : Count> (Int, @owned <τ_0_0 : Count> { var S<τ_0_0> } <τ_0_0>) -> Bool
  %5 = alloc_box $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>
  %5a = project_box %5 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>, 0
  copy_addr %2 to [initialization] %5a : $*S<T>
  %7 = partial_apply %4<T>(%0, %5) : $@convention(thin) <τ_0_0 where τ_0_0 : Count> (Int, @owned <τ_0_0 : Count> { var S<τ_0_0> } <τ_0_0>) -> Bool
  %8 = apply %3(%7) : $@convention(thin) (@owned @callee_owned () -> Bool) -> Bool
  strong_release %1 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>
// CHECK: return
  return %8 : $Bool
}

// CHECK-LABEL: sil shared @_T08closure2Tf0ns_n
// CHECK: bb0
// CHECK: return
// CHECK-NOT: bb1

// CHECK-LABEL: sil shared @closure2
sil shared @closure2 : $@convention(thin) <T where T : Count> (Int, @owned <τ_0_0 : Count> { var S<τ_0_0> } <T>) -> Bool {
// CHECK: bb0
bb0(%0 : $Int, %1 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>):
  %2 = project_box %1 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>, 0
  %3 = function_ref @binary : $@convention(thin) (Int, Int) -> Bool
  %4 = alloc_stack $S<T>
  copy_addr %2 to [initialization] %4 : $*S<T>
  %6 = function_ref @get : $@convention(method) <τ_0_0 where τ_0_0 : Count> (@in S<τ_0_0>) -> Int
  %7 = apply %6<T>(%4) : $@convention(method) <τ_0_0 where τ_0_0 : Count> (@in S<τ_0_0>) -> Int
  %8 = apply %3(%0, %7) : $@convention(thin) (Int, Int) -> Bool
  dealloc_stack %4 : $*S<T>
  strong_release %1 : $<τ_0_0 where τ_0_0 : Count> { var S<τ_0_0> } <T>
// CHECK: return
  return %8 : $Bool
}

// CHECK-LABEL: sil [transparent] [serialized] @binary
sil [transparent] [serialized] @binary : $@convention(thin) (Int, Int) -> Bool

// CHECK-LABEL: sil @destroy_stack_value_after_closure
sil @destroy_stack_value_after_closure : $@convention(thin) <T> (@in T) -> @out T {
// CHECK: bb0
bb0(%0 : $*T, %1 : $*T):
  // CHECK: [[STACK:%.*]] = alloc_stack
  // CHECK: copy_addr %1 to [initialization] [[STACK]]
  // CHECK: [[APPLIED:%.*]] = function_ref
  %3 = function_ref @applied : $@convention(thin) <τ_0_0> (@owned <τ_0_0> { var τ_0_0 } <τ_0_0>) -> ()
  %4 = alloc_box $<τ_0_0> { var τ_0_0 } <T>
  %4a = project_box %4 : $<τ_0_0> { var τ_0_0 } <T>, 0
  copy_addr %1 to [initialization] %4a : $*T
  // CHECK: [[PARTIAL:%.*]] = partial_apply [[APPLIED]]<T>([[STACK]])
  %6 = partial_apply %3<T>(%4) : $@convention(thin) <τ_0_0> (@owned <τ_0_0> { var τ_0_0 } <τ_0_0>) -> ()
  // CHECK: debug_value [[PARTIAL]]
  debug_value %6 : $@callee_owned () -> ()
  // CHECK: strong_retain [[PARTIAL]]
  strong_retain %6 : $@callee_owned () -> ()
  // CHECK: apply [[PARTIAL]]
  %9 = apply %6() : $@callee_owned () -> ()
  copy_addr %1 to [initialization] %0 : $*T
  // CHECK: strong_release [[PARTIAL]]
  strong_release %6 : $@callee_owned () -> ()
  // CHECK: destroy_addr [[STACK]]
  // CHECK: destroy_addr %1
  destroy_addr %1 : $*T
  %13 = tuple ()
  return %13 : $()
}

sil @applied : $@convention(thin) <T> (@owned <τ_0_0> { var τ_0_0 } <T>) -> () {
bb0(%0 : $<τ_0_0> { var τ_0_0 } <T>):
  %1 = project_box %0 : $<τ_0_0> { var τ_0_0 } <T>, 0
  %2 = function_ref @consume : $@convention(thin) <τ_0_0> (@in τ_0_0) -> ()
  %3 = alloc_stack $T
  copy_addr %1 to [initialization] %3 : $*T
  %5 = apply %2<T>(%3) : $@convention(thin) <τ_0_0> (@in τ_0_0) -> ()
  dealloc_stack %3 : $*T
  strong_release %0 : $<τ_0_0> { var τ_0_0 } <T>
  %8 = tuple ()
  return %8 : $()
}

sil hidden [noinline] @consume : $@convention(thin) <T> (@in T) -> () {
bb0(%0 : $*T):
  debug_value_addr %0 : $*T
  destroy_addr %0 : $*T
  %3 = tuple ()
  return %3 : $()
}

class ThrowBaseClass {
  required init() throws
  init(noFail: ())
}

class ThrowDerivedClass : ThrowBaseClass {
  //final init(failBeforeFullInitialization: Int) throws
}

sil @throwing_unwrap : $@convention(thin) (Int) -> (Int, @error Error)
sil @fake_throwing_init : $@convention(method) (Int, @owned ThrowDerivedClass) -> (@owned ThrowDerivedClass, @error Error)

sil hidden @try_apply_during_chaining_init : $@convention(method) (Int, @owned ThrowDerivedClass) -> (@owned ThrowDerivedClass, @error Error) {
// %0                                             // users: %11, %5
// %1                                             // user: %7
bb0(%0 : $Int, %1 : $ThrowDerivedClass):
  %2 = alloc_box ${ var ThrowDerivedClass }, let, name "self"
  %3 = mark_uninitialized [delegatingself] %2 : ${ var ThrowDerivedClass }
  %4 = project_box %3 : ${ var ThrowDerivedClass }, 0
  store %1 to %4 : $*ThrowDerivedClass
  %8 = load %4 : $*ThrowDerivedClass
  %9 = function_ref @fake_throwing_init : $@convention(method) (Int, @owned ThrowDerivedClass) -> (@owned ThrowDerivedClass, @error Error)
  %10 = function_ref @throwing_unwrap : $@convention(thin) (Int) -> (Int, @error Error)
  try_apply %10(%0) : $@convention(thin) (Int) -> (Int, @error Error), normal bb1, error bb3

// %12                                            // user: %13
bb1(%12 : $Int):                                  // Preds: bb0
  try_apply %9(%12, %8) : $@convention(method) (Int, @owned ThrowDerivedClass) -> (@owned ThrowDerivedClass, @error Error), normal bb2, error bb4

// %14                                            // user: %15
bb2(%14 : $ThrowDerivedClass):                    // Preds: bb1
  store %14 to %4 : $*ThrowDerivedClass
  %16 = load %4 : $*ThrowDerivedClass
  strong_retain %16 : $ThrowDerivedClass
  strong_release %3 : ${ var ThrowDerivedClass }
  return %16 : $ThrowDerivedClass

// %20                                            // user: %22
bb3(%20 : $Error):                                // Preds: bb0
  strong_release %8 : $ThrowDerivedClass
  br bb5(%20 : $Error)

// %23                                            // user: %24
bb4(%23 : $Error):                                // Preds: bb1
  br bb5(%23 : $Error)

// %25                                            // user: %27
bb5(%25 : $Error):                                // Preds: bb4 bb3
  strong_release %3 : ${ var ThrowDerivedClass }
  throw %25 : $Error
}

// CHECK-LABEL: sil @deal_with_wrong_nesting
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[STACK1:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK:      bb1:
// CHECK-NEXT:   dealloc_stack [[BOX]]
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK:      bb2:
// CHECK:        store
// CHECK:        [[STACK2:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   dealloc_stack [[STACK2]] : $*Bool, loc "testloc":27:27
// CHECK-NEXT:   dealloc_stack [[BOX]] : $*Int, loc "testloc":27:27
// CHECK-NEXT:   dealloc_stack [[STACK1]] : $*Bool, loc "testloc":27:27
// CHECK:      bb3:
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @deal_with_wrong_nesting : $(Int) -> () {
bb0(%0 : $Int):
  %as1 = alloc_stack $Bool
  %1 = alloc_box ${ var Int }
  cond_br undef, bb1, bb2

bb1:
  strong_release %1 : ${ var Int }
  dealloc_stack %as1 : $*Bool
  br bb3

bb2:
  %1a = project_box %1 : ${ var Int }, 0
  %2 = store %0 to %1a : $*Int
  dealloc_stack %as1 : $*Bool
  %3 = load %1a : $*Int
  %as2 = alloc_stack $Bool
  strong_release %1 : ${ var Int }
  dealloc_stack %as2 : $*Bool, loc "testloc":27:27
  br bb3

bb3:
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @wrong_nesting_with_alloc_ref
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[REF:%[0-9]+]] = alloc_ref [stack] $SomeClass
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK:        store
// CHECK:        dealloc_stack [[BOX]]
// CHECK-NEXT:   dealloc_ref [stack] [[REF]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @wrong_nesting_with_alloc_ref : $(Int) -> () {
bb0(%0 : $Int):
  %as1 = alloc_ref [stack] $SomeClass
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  %2 = store %0 to %1a : $*Int
  dealloc_ref [stack] %as1 : $SomeClass
  %3 = load %1a : $*Int
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @nesting_and_unreachable1
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[STACK1:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK:      bb1:
// CHECK-NEXT:   [[STACK2:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   dealloc_stack [[STACK2]]
// CHECK-NEXT:   unreachable
// CHECK:      bb2:
// CHECK:        store
// CHECK:        dealloc_stack [[BOX]]
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @nesting_and_unreachable1 : $(Int) -> () {
bb0(%0 : $Int):
  %as1 = alloc_stack $Bool
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  cond_br undef, bb1, bb2

bb1:
  %as2 = alloc_stack $Bool
  dealloc_stack %as2 : $*Bool
  unreachable

bb2:
  %2 = store %0 to %1a : $*Int
  dealloc_stack %as1 : $*Bool
  %3 = load %1a : $*Int
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @nesting_and_unreachable2
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[STACK1:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK:      bb1:
// CHECK-NEXT:   [[STACK2:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   dealloc_stack [[STACK2]]
// CHECK-NEXT:   dealloc_stack [[BOX]]
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK-NEXT:   unreachable
// CHECK:      bb2:
// CHECK:        store
// CHECK:        dealloc_stack [[BOX]]
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @nesting_and_unreachable2 : $(Int) -> () {
bb0(%0 : $Int):
  %as1 = alloc_stack $Bool
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  cond_br undef, bb1, bb2

bb1:
  %as2 = alloc_stack $Bool
  strong_release %1 : ${ var Int }
  dealloc_stack %as2 : $*Bool
  unreachable

bb2:
  %2 = store %0 to %1a : $*Int
  dealloc_stack %as1 : $*Bool
  %3 = load %1a : $*Int
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @nesting_and_unreachable3
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK-NEXT:   [[STACK:%[0-9]+]] = alloc_stack $Bool
// CHECK:      bb1:
// CHECK-NEXT:   dealloc_stack [[STACK]]
// CHECK-NEXT:   dealloc_stack [[BOX]]
// CHECK-NEXT:   unreachable
// CHECK:      bb2:
// CHECK:        store
// CHECK:        dealloc_stack [[STACK]]
// CHECK-NEXT:   dealloc_stack [[BOX]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @nesting_and_unreachable3 : $(Int) -> () {
bb0(%0 : $Int):
  %1 = alloc_box ${ var Int }
  %as1 = alloc_stack $Bool
  %1a = project_box %1 : ${ var Int }, 0
  cond_br undef, bb1, bb2

bb1:
  strong_release %1 : ${ var Int }
  unreachable

bb2:
  %2 = store %0 to %1a : $*Int
  %3 = load %1a : $*Int
  dealloc_stack %as1 : $*Bool
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @nesting_and_unreachable4
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK:      bb1:
// CHECK-NEXT:   unreachable
// CHECK:      bb2:
// CHECK:        store
// CHECK:        dealloc_stack [[BOX]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @nesting_and_unreachable4 : $(Int) -> () {
bb0(%0 : $Int):
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  cond_br undef, bb1, bb2

bb1:
  unreachable

bb2:
  %2 = store %0 to %1a : $*Int
  %3 = load %1a : $*Int
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @nesting_and_unreachable5
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK:      bb1:
// CHECK-NEXT:   {{.*}} = alloc_stack $Bool
// CHECK-NEXT:   {{.*}} = alloc_stack $Bool
// CHECK-NEXT:   unreachable
// CHECK:      bb2:
// CHECK:        store
// CHECK:        dealloc_stack [[BOX]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
sil @nesting_and_unreachable5 : $(Int) -> () {
bb0(%0 : $Int):
  %1 = alloc_box ${ var Int }
  %1a = project_box %1 : ${ var Int }, 0
  cond_br undef, bb1, bb2

bb1:
  %as1 = alloc_stack $Bool
  %as2 = alloc_stack $Bool
  unreachable

bb2:
  %2 = store %0 to %1a : $*Int
  %3 = load %1a : $*Int
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()
}

// CHECK-LABEL: sil @nesting_and_unreachable_critical_edge
// CHECK:      bb0(%0 : $Int):
// CHECK-NEXT:   [[BOX:%[0-9]+]] = alloc_stack $Int
// CHECK-NEXT:   [[STACK1:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   cond_br
// CHECK:      bb1:
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK-NEXT:   br bb5
// CHECK:      bb2:
// CHECK-NEXT:   [[STACK2:%[0-9]+]] = alloc_stack $Bool
// CHECK-NEXT:   cond_br
// CHECK:      bb3:
// CHECK-NEXT:   dealloc_stack [[STACK2]]
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK-NEXT:   br bb5
// CHECK:      bb4:
// CHECK:        store
// CHECK:        dealloc_stack [[STACK2]]
// CHECK-NEXT:   dealloc_stack [[STACK1]]
// CHECK-NEXT:   dealloc_stack [[BOX]]
// CHECK-NEXT:   tuple
// CHECK-NEXT:   return
// CHECK:      bb5:
// CHECK-NEXT:   dealloc_stack [[BOX]]
// CHECK-NEXT:   unreachable
sil @nesting_and_unreachable_critical_edge : $(Int) -> () {
bb0(%0 : $Int):
  %1 = alloc_box ${ var Int }
  %as1 = alloc_stack $Bool
  %1a = project_box %1 : ${ var Int }, 0
  cond_br undef, bb1, bb3

bb1:
  %as2 = alloc_stack $Bool
  cond_br undef, bb2, bb3

bb2:
  %2 = store %0 to %1a : $*Int
  %3 = load %1a : $*Int
  dealloc_stack %as2 : $*Bool
  dealloc_stack %as1 : $*Bool
  strong_release %1 : ${ var Int }
  %r = tuple ()
  %5 = return %r : $()

bb3:
  strong_release %1 : ${ var Int }
  unreachable

}