test/SILOptimizer/cast_optimizer_conditional_conformance.sil

// RUN: %target-sil-opt -enable-sil-verify-all -wmo -performance-constant-propagation -simplify-cfg -sil-combine -jumpthread-simplify-cfg -sil-combine -devirtualizer -generic-specializer %s | %FileCheck %s
//
// <rdar://problem/46322928> Failure to devirtualize a protocol method applied to an opened existential blocks implemention of
// DataProtocol.
sil_stage canonical

import Builtin
import Swift
import SwiftShims

public protocol HasFoo {
  func foo()
}

@inline(never) func testHasFoo<T>(_ t: T)

struct S1<T> {
  init(_: T)
}

extension S1 : HasFoo where T == UInt8 {
  func foo()
}

// ConstantPropagation converts checked_cast_addr to unconditional_checked_cast_addr.
// SimplifyCFG removes the trivial branch.
// SILCombine replaces the unconditional_checked_cast_addr with init_existential_addr + copy_addr
//            and simplifies the switch condition.
// JumpThreadSimplifyCFG eliminates the dead switch condition.
// SILCombine specializes the witness_method instruction to S1<UInt8>.
// Devirtualization replaces the witness invocation with a direct call.
//
// CHECK-LABEL: sil shared [noinline] @testSpecializedS1 : $@convention(thin) (S1<UInt8>) -> () {
// CHECK: bb0(%0 : $S1<UInt8>):
// CHECK: [[EXIS:%.*]] = alloc_stack $HasFoo
// CHECK: [[S1:%.*]] = alloc_stack $S1<UInt8>
// CHECK: store %0 to [[S1]] : $*S1<UInt8>
// CHECK: [[OPT:%.*]] = alloc_stack $Optional<HasFoo>
// CHECK: [[INIT_DATA:%.*]] = init_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[EXIS_ADDR:%.*]] = init_existential_addr [[INIT_DATA]] : $*HasFoo, $S1<UInt8>
// CHECK: copy_addr [take] [[S1]] to [initialization] [[EXIS_ADDR]] : $*S1<UInt8>
// CHECK: inject_enum_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[DATA:%.*]] = unchecked_take_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: copy_addr [take] [[DATA]] to [initialization] [[EXIS]] : $*HasFoo
// CHECK: [[OPEN_EXIS_ADDR:%.*]] = open_existential_addr immutable_access [[EXIS]] : $*HasFoo to $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
// CHECK: [[OPEN_ADDR:%.*]] = unchecked_addr_cast [[OPEN_EXIS_ADDR]] : $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo to $*S1<UInt8>
// CHECK: [[F:%.*]] = function_ref @witnessS1 : $@convention(witness_method: HasFoo) (@in_guaranteed S1<UInt8>) -> ()
// CHECK: apply [[F]]([[OPEN_ADDR]]) : $@convention(witness_method: HasFoo) (@in_guaranteed S1<UInt8>) -> ()
// CHECK-LABEL: } // end sil function 'testSpecializedS1'
sil shared [noinline] @testSpecializedS1 : $@convention(thin) (S1<UInt8>) -> () {
bb0(%0 : $S1<UInt8>):
  debug_value %0 : $S1<UInt8>, let, name "t", argno 1
  debug_value %0 : $S1<UInt8>, let, name "t", argno 1
  %3 = alloc_stack $HasFoo
  %4 = alloc_stack $S1<UInt8>
  store %0 to %4 : $*S1<UInt8>
  %6 = alloc_stack $Optional<HasFoo>
  %7 = init_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  checked_cast_addr_br take_always S1<UInt8> in %4 : $*S1<UInt8> to HasFoo in %7 : $*HasFoo, bb1, bb2

bb1:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  br bb3

bb2:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.none!enumelt
  br bb3

bb3:
  switch_enum_addr %6 : $*Optional<HasFoo>, case #Optional.some!enumelt.1: bb4, case #Optional.none!enumelt: bb5

bb4:
  %14 = unchecked_take_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  copy_addr [take] %14 to [initialization] %3 : $*HasFoo
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S1<UInt8>
  %18 = open_existential_addr immutable_access %3 : $*HasFoo to $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
  %19 = witness_method $@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo, #HasFoo.foo!1 : <Self where Self : HasFoo> (Self) -> () -> (), %18 : $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  %20 = apply %19<@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo>(%18) : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  destroy_addr %3 : $*HasFoo
  br bb6

bb5:
  destroy_addr %6 : $*Optional<HasFoo>
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S1<UInt8>
  br bb6

bb6:
  dealloc_stack %3 : $*HasFoo
  %28 = tuple ()
  return %28 : $()
}

// CHECK-LABEL: sil shared [noinline] @testSpecializedS1Negative : $@convention(thin) (S1<Int8>) -> () {
// CHECK: bb0(%0 : $S1<Int8>):
// CHECK: [[EXIS:%.*]] = alloc_stack $HasFoo
// CHECK: [[VAL:%.*]] = alloc_stack $S1<Int8>
// CHECK: store %0 to [[VAL]] : $*S1<Int8>
// CHECK: [[OPT:%.*]] = alloc_stack $Optional<HasFoo>
// CHECK: [[IEDA:%.*]] = init_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: checked_cast_addr_br take_always S1<Int8> in [[VAL]] : $*S1<Int8> to HasFoo in [[IEDA]] : $*HasFoo, bb1, bb2
// bbs...
// CHECK: switch_enum_addr [[OPT]] : $*Optional<HasFoo>, case #Optional.some!enumelt.1: bb4, case #Optional.none!enumelt: bb5
// bbs...
// CHECK: [[UNWRAP:%.*]] = unchecked_take_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: copy_addr [take] [[UNWRAP]] to [initialization] [[EXIS]] : $*HasFoo
// CHECK: [[OPEN:%.*]] = open_existential_addr immutable_access [[EXIS]] : $*HasFoo to $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
// CHECK: [[WM:%.*]] = witness_method $@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo, #HasFoo.foo!1 : <Self where Self : HasFoo> (Self) -> () -> (), [[OPEN]] : $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
// CHECK: apply [[WM]]<@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo>([[OPEN]]) : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
// CHECK-LABEL: } // end sil function 'testSpecializedS1Negative'
sil shared [noinline] @testSpecializedS1Negative : $@convention(thin) (S1<Int8>) -> () {
bb0(%0 : $S1<Int8>):
  debug_value %0 : $S1<Int8>, let, name "t", argno 1
  debug_value %0 : $S1<Int8>, let, name "t", argno 1
  %3 = alloc_stack $HasFoo
  %4 = alloc_stack $S1<Int8>
  store %0 to %4 : $*S1<Int8>
  %6 = alloc_stack $Optional<HasFoo>
  %7 = init_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  checked_cast_addr_br take_always S1<Int8> in %4 : $*S1<Int8> to HasFoo in %7 : $*HasFoo, bb1, bb2

bb1:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  br bb3

bb2:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.none!enumelt
  br bb3

bb3:
  switch_enum_addr %6 : $*Optional<HasFoo>, case #Optional.some!enumelt.1: bb4, case #Optional.none!enumelt: bb5

bb4:
  %14 = unchecked_take_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  copy_addr [take] %14 to [initialization] %3 : $*HasFoo
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S1<Int8>
  %18 = open_existential_addr immutable_access %3 : $*HasFoo to $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
  %19 = witness_method $@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo, #HasFoo.foo!1 : <Self where Self : HasFoo> (Self) -> () -> (), %18 : $*@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  %20 = apply %19<@opened("4E16CBC0-FD9F-11E8-A311-D0817AD9F6DD") HasFoo>(%18) : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  destroy_addr %3 : $*HasFoo
  br bb6

bb5:
  destroy_addr %6 : $*Optional<HasFoo>
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S1<Int8>
  br bb6

bb6:
  dealloc_stack %3 : $*HasFoo
  %28 = tuple ()
  return %28 : $()
}

struct S2<T> {
  init(_: T) {}
}

protocol P {}

extension S2 : HasFoo where T : P {
  func foo() {}
}

struct IsP : P {}

// CHECK-LABEL: sil shared [noinline] @testSpecializedS2 : $@convention(thin) (S2<IsP>) -> () {
// CHECK: bb0(%0 : $S2<IsP>):
// CHECK: [[EXIS:%.*]] = alloc_stack $HasFoo
// CHECK: [[S2:%.*]] = alloc_stack $S2<IsP>
// CHECK: store %0 to [[S2]] : $*S2<IsP>
// CHECK: [[OPT:%.*]] = alloc_stack $Optional<HasFoo>
// CHECK: [[INIT_DATA:%.*]] = init_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[EXIS_ADDR:%.*]] = init_existential_addr [[INIT_DATA]] : $*HasFoo, $S2<IsP>
// CHECK: copy_addr [take] [[S2]] to [initialization] [[EXIS_ADDR]] : $*S2<IsP>
// CHECK: inject_enum_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[DATA:%.*]] = unchecked_take_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: copy_addr [take] [[DATA]] to [initialization] [[EXIS]] : $*HasFoo
// CHECK: [[OPEN_EXIS_ADDR:%.*]] = open_existential_addr immutable_access [[EXIS]] : $*HasFoo to $*@opened("4E16D1CE-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
// CHECK: [[OPEN_ADDR:%.*]] = unchecked_addr_cast [[OPEN_EXIS_ADDR]] : $*@opened("4E16D1CE-FD9F-11E8-A311-D0817AD9F6DD") HasFoo to $*S2<IsP>
// CHECK: [[F:%.*]] = function_ref @$s9witnessS24main3IsPV_Tg5 : $@convention(witness_method: HasFoo) (S2<IsP>) -> ()
// CHECK: [[ARG:%.*]] = load [[OPEN_ADDR]] : $*S2<IsP>
// CHECK: apply [[F]]([[ARG]]) : $@convention(witness_method: HasFoo) (S2<IsP>) -> ()
// CHECK-LABEL: } // end sil function 'testSpecializedS2'
sil shared [noinline] @testSpecializedS2 : $@convention(thin) (S2<IsP>) -> () {
bb0(%0 : $S2<IsP>):
  debug_value %0 : $S2<IsP>, let, name "t", argno 1
  debug_value %0 : $S2<IsP>, let, name "t", argno 1
  %3 = alloc_stack $HasFoo
  %4 = alloc_stack $S2<IsP>
  store %0 to %4 : $*S2<IsP>
  %6 = alloc_stack $Optional<HasFoo>
  %7 = init_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  checked_cast_addr_br take_always S2<IsP> in %4 : $*S2<IsP> to HasFoo in %7 : $*HasFoo, bb1, bb2

bb1:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  br bb3

bb2:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.none!enumelt
  br bb3

bb3:
  switch_enum_addr %6 : $*Optional<HasFoo>, case #Optional.some!enumelt.1: bb4, case #Optional.none!enumelt: bb5

bb4:
  %14 = unchecked_take_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  copy_addr [take] %14 to [initialization] %3 : $*HasFoo
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S2<IsP>
  %18 = open_existential_addr immutable_access %3 : $*HasFoo to $*@opened("4E16D1CE-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
  %19 = witness_method $@opened("4E16D1CE-FD9F-11E8-A311-D0817AD9F6DD") HasFoo, #HasFoo.foo!1 : <Self where Self : HasFoo> (Self) -> () -> (), %18 : $*@opened("4E16D1CE-FD9F-11E8-A311-D0817AD9F6DD") HasFoo : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  %20 = apply %19<@opened("4E16D1CE-FD9F-11E8-A311-D0817AD9F6DD") HasFoo>(%18) : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  destroy_addr %3 : $*HasFoo
  br bb6

bb5:
  destroy_addr %6 : $*Optional<HasFoo>
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S2<IsP>
  br bb6

bb6:
  dealloc_stack %3 : $*HasFoo
  %28 = tuple ()
  return %28 : $()
}

class C {
  init() {}
}

struct S3<T> {
  init(_: T) {}
}

extension S3 : HasFoo where T : AnyObject {
  func foo() {}
}

// CHECK-LABEL: sil shared [noinline] @testSpecializedS3 : $@convention(thin) (S3<C>) -> () {
// CHECK: bb0(%0 : $S3<C>):
// CHECK: [[EXIS:%.*]] = alloc_stack $HasFoo
// CHECK: [[S3:%.*]] = alloc_stack $S3<C>
// CHECK: store %0 to [[S3]] : $*S3<C>
// CHECK: [[OPT:%.*]] = alloc_stack $Optional<HasFoo>
// CHECK: [[INIT_DATA:%.*]] = init_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[EXIS_ADDR:%.*]] = init_existential_addr [[INIT_DATA]] : $*HasFoo, $S3<C>
// CHECK: copy_addr [take] [[S3]] to [initialization] [[EXIS_ADDR]] : $*S3<C>
// CHECK: inject_enum_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[DATA:%.*]] = unchecked_take_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: copy_addr [take] [[DATA]] to [initialization] [[EXIS]] : $*HasFoo
// CHECK: [[OPEN_EXIS_ADDR:%.*]] = open_existential_addr immutable_access [[EXIS]] : $*HasFoo to $*@opened("4E16D5E8-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
// CHECK: [[OPEN_ADDR:%.*]] = unchecked_addr_cast [[OPEN_EXIS_ADDR]] : $*@opened("4E16D5E8-FD9F-11E8-A311-D0817AD9F6DD") HasFoo to $*S3<C>
// CHECK: [[F:%.*]] = function_ref @$s9witnessS34main1CC_Tg5 : $@convention(witness_method: HasFoo) (S3<C>) -> ()
// CHECK: [[ARG:%.*]] = load [[OPEN_ADDR]] : $*S3<C>
// CHECK: apply [[F]]([[ARG]]) : $@convention(witness_method: HasFoo) (S3<C>) -> ()
// CHECK-LABEL: } // end sil function 'testSpecializedS3'
sil shared [noinline] @testSpecializedS3 : $@convention(thin) (S3<C>) -> () {
bb0(%0 : $S3<C>):
  debug_value %0 : $S3<C>, let, name "t", argno 1
  debug_value %0 : $S3<C>, let, name "t", argno 1
  %3 = alloc_stack $HasFoo
  %4 = alloc_stack $S3<C>
  store %0 to %4 : $*S3<C>
  %6 = alloc_stack $Optional<HasFoo>
  %7 = init_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  checked_cast_addr_br take_always S3<C> in %4 : $*S3<C> to HasFoo in %7 : $*HasFoo, bb1, bb2

bb1:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  br bb3

bb2:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.none!enumelt
  br bb3

bb3:
  switch_enum_addr %6 : $*Optional<HasFoo>, case #Optional.some!enumelt.1: bb4, case #Optional.none!enumelt: bb5

bb4:
  %14 = unchecked_take_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  copy_addr [take] %14 to [initialization] %3 : $*HasFoo
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S3<C>
  %18 = open_existential_addr immutable_access %3 : $*HasFoo to $*@opened("4E16D5E8-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
  %19 = witness_method $@opened("4E16D5E8-FD9F-11E8-A311-D0817AD9F6DD") HasFoo, #HasFoo.foo!1 : <Self where Self : HasFoo> (Self) -> () -> (), %18 : $*@opened("4E16D5E8-FD9F-11E8-A311-D0817AD9F6DD") HasFoo : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  %20 = apply %19<@opened("4E16D5E8-FD9F-11E8-A311-D0817AD9F6DD") HasFoo>(%18) : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  destroy_addr %3 : $*HasFoo
  br bb6

bb5:
  destroy_addr %6 : $*Optional<HasFoo>
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S3<C>
  br bb6

bb6:
  dealloc_stack %3 : $*HasFoo
  %28 = tuple ()
  return %28 : $()
}

class SubC : C {}

struct S4<T> {
  init(_: T) {}
}

extension S4 : HasFoo where T : C {
  func foo() {}
}

// CHECK-LABEL: sil shared [noinline] @testSpecializedS4 : $@convention(thin) (S4<SubC>) -> () {
// CHECK: bb0(%0 : $S4<SubC>):
// CHECK: [[EXIS:%.*]] = alloc_stack $HasFoo
// CHECK: [[S3:%.*]] = alloc_stack $S4<SubC>
// CHECK: store %0 to [[S3]] : $*S4<SubC>
// CHECK: [[OPT:%.*]] = alloc_stack $Optional<HasFoo>
// CHECK: [[INIT_DATA:%.*]] = init_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[EXIS_ADDR:%.*]] = init_existential_addr [[INIT_DATA]] : $*HasFoo, $S4<SubC>
// CHECK: copy_addr [take] [[S3]] to [initialization] [[EXIS_ADDR]] : $*S4<SubC>
// CHECK: inject_enum_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: [[DATA:%.*]] = unchecked_take_enum_data_addr [[OPT]] : $*Optional<HasFoo>, #Optional.some!enumelt.1
// CHECK: copy_addr [take] [[DATA]] to [initialization] [[EXIS]] : $*HasFoo
// CHECK: [[OPEN_EXIS_ADDR:%.*]] = open_existential_addr immutable_access [[EXIS]] : $*HasFoo to $*@opened("4E16E402-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
// CHECK: [[OPEN_ADDR:%.*]] = unchecked_addr_cast [[OPEN_EXIS_ADDR]] : $*@opened("4E16E402-FD9F-11E8-A311-D0817AD9F6DD") HasFoo to $*S4<SubC>
// CHECK: [[F:%.*]] = function_ref @$s9witnessS44main4SubCC_Tg5 : $@convention(witness_method: HasFoo) (S4<SubC>) -> ()
// CHECK: [[ARG:%.*]] = load [[OPEN_ADDR]] : $*S4<SubC>
// CHECK: apply [[F]]([[ARG]]) : $@convention(witness_method: HasFoo) (S4<SubC>) -> ()
// CHECK: } // end sil function 'testSpecializedS4'
sil shared [noinline] @testSpecializedS4 : $@convention(thin) (S4<SubC>) -> () {
bb0(%0 : $S4<SubC>):
  debug_value %0 : $S4<SubC>, let, name "t", argno 1
  debug_value %0 : $S4<SubC>, let, name "t", argno 1
  %3 = alloc_stack $HasFoo
  %4 = alloc_stack $S4<SubC>
  store %0 to %4 : $*S4<SubC>
  %6 = alloc_stack $Optional<HasFoo>
  %7 = init_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  checked_cast_addr_br take_always S4<SubC> in %4 : $*S4<SubC> to HasFoo in %7 : $*HasFoo, bb1, bb2

bb1:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  br bb3

bb2:
  inject_enum_addr %6 : $*Optional<HasFoo>, #Optional.none!enumelt
  br bb3

bb3:
  switch_enum_addr %6 : $*Optional<HasFoo>, case #Optional.some!enumelt.1: bb4, case #Optional.none!enumelt: bb5

bb4:
  %14 = unchecked_take_enum_data_addr %6 : $*Optional<HasFoo>, #Optional.some!enumelt.1
  copy_addr [take] %14 to [initialization] %3 : $*HasFoo
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S4<SubC>
  %18 = open_existential_addr immutable_access %3 : $*HasFoo to $*@opened("4E16E402-FD9F-11E8-A311-D0817AD9F6DD") HasFoo
  %19 = witness_method $@opened("4E16E402-FD9F-11E8-A311-D0817AD9F6DD") HasFoo, #HasFoo.foo!1 : <Self where Self : HasFoo> (Self) -> () -> (), %18 : $*@opened("4E16E402-FD9F-11E8-A311-D0817AD9F6DD") HasFoo : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  %20 = apply %19<@opened("4E16E402-FD9F-11E8-A311-D0817AD9F6DD") HasFoo>(%18) : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : HasFoo> (@in_guaranteed τ_0_0) -> ()
  destroy_addr %3 : $*HasFoo
  br bb6

bb5:
  destroy_addr %6 : $*Optional<HasFoo>
  dealloc_stack %6 : $*Optional<HasFoo>
  dealloc_stack %4 : $*S4<SubC>
  br bb6

bb6:
  dealloc_stack %3 : $*HasFoo
  %28 = tuple ()
  return %28 : $()
}


sil private [transparent] [thunk] @witnessS1 : $@convention(witness_method: HasFoo) (@in_guaranteed S1<UInt8>) -> () {
bb0(%0 : $*S1<UInt8>):
  %1 = tuple ()
  return %1 : $()
}


sil private [transparent] [thunk] @witnessS2 : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : P> (@in_guaranteed S2<τ_0_0>) -> () {
bb0(%0 : $*S2<τ_0_0>):
  %1 = tuple ()
  return %1 : $()
}

sil private [transparent] [thunk] @witnessS3 : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : AnyObject> (@in_guaranteed S3<τ_0_0>) -> () {
bb0(%0 : $*S3<τ_0_0>):
  %1 = tuple ()
  return %1 : $()
}

sil private [transparent] [thunk] @witnessS4 : $@convention(witness_method: HasFoo) <τ_0_0 where τ_0_0 : C> (@in_guaranteed S4<τ_0_0>) -> () {
bb0(%0 : $*S4<τ_0_0>):
  %1 = tuple ()
  return %1 : $()
}

sil_vtable C {}

sil_vtable SubC {}

sil_witness_table hidden <T where T == UInt8> S1<T>: HasFoo module tot {
  method #HasFoo.foo!1: <Self where Self : HasFoo> (Self) -> () -> () : @witnessS1
}

sil_witness_table hidden <T where T : P> S2<T>: HasFoo module tot {
  method #HasFoo.foo!1: <Self where Self : HasFoo> (Self) -> () -> () : @witnessS2
  conditional_conformance (T: P): dependent
}

sil_witness_table hidden IsP: P module tot {
}

sil_witness_table hidden <T where T : AnyObject> S3<T>: HasFoo module tot {
  method #HasFoo.foo!1: <Self where Self : HasFoo> (Self) -> () -> () : @witnessS3
}

sil_witness_table hidden <T where T : C> S4<T>: HasFoo module tot {
  method #HasFoo.foo!1: <Self where Self : HasFoo> (Self) -> () -> () : @witnessS4
}