test/SILOptimizer/existential_type_propagation.sil

// RUN: %target-sil-opt -enable-sil-verify-all %s -sil-combine -inline -sil-combine | FileCheck %s

// Check that type propagation is performed correctly for existentials.
// The concrete type set in init_existential instructions should be propagated
// all the way down to witness_method instructions.
// 
// If copy_addr instructions are used to copy one existential into another,
// the information about the concrete type should be still propagated 
// correctly through it.

sil_stage canonical

import Builtin
import Swift
import SwiftShims

public protocol ReaderWriterType {
  init()
  func read(index: Int32) -> Int32
  mutating func write(index: Int32, value: Int32)
}

public final class ArrayClassReaderWriter : ReaderWriterType {
  @sil_stored private final var elements: [Int32] { get set }
  @inline(never) public init()
  @inline(never) public final func read(index: Int32) -> Int32
  public final func write(index: Int32, value: Int32)
   deinit 
}

@inline(never) public func readValues() -> Int32


sil_global [fragile] @_swiftEmptyArrayStorage : $_SwiftEmptyArrayStorage


sil [noinline] @_TFC28existential_type_propagation22ArrayClassReaderWritercfMS0_FT_S0_ : $@convention(method) (@owned ArrayClassReaderWriter) -> @owned ArrayClassReaderWriter
sil [noinline] @_TFC28existential_type_propagation22ArrayClassReaderWriterCfMS0_FT_S0_ : $@convention(thin) (@thick ArrayClassReaderWriter.Type) -> @owned ArrayClassReaderWriter
sil [noinline] @_TFC28existential_type_propagation22ArrayClassReaderWriter4readfS0_FSiSi : $@convention(method) (Int32, @guaranteed ArrayClassReaderWriter) -> Int32
sil [transparent] [thunk] @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_CuRq_S1__fMq_FT_q_ : $@convention(witness_method) (@thick ArrayClassReaderWriter.Type) -> @out ArrayClassReaderWriter
sil [transparent] [thunk] @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_4readuRq_S1__fq_FSiSi : $@convention(witness_method) (Int32, @in_guaranteed ArrayClassReaderWriter) -> Int32
sil [transparent] [thunk] @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_5writeuRq_S1__fRq_FTSi5valueSi_T_ : $@convention(witness_method) (Int32, Int32, @inout ArrayClassReaderWriter) -> ()

// CHECK-LABEL: sil [noinline] @test_existential_type_propagation : $@convention(thin) () -> Int32
// CHECK-NOT: init_existential_addr
// CHECK-NOT: open_existential_addr
// CHECK-NOT: witness_method
// CHECK: function_ref @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_4readuRq_S1__fq_FSiSi : $@convention(witness_method) (Int32, @in_guaranteed ArrayClassReaderWriter) -> Int32
// CHECK: return
sil [noinline] @test_existential_type_propagation : $@convention(thin) () -> Int32 {
bb0:
  %0 = alloc_stack $Int32
  %1 = alloc_stack $ReaderWriterType
  // Here we set the concrete type information.  
  %2 = init_existential_addr %1 : $*ReaderWriterType, $ArrayClassReaderWriter
  %3 = function_ref @_TFC28existential_type_propagation22ArrayClassReaderWriterCfMS0_FT_S0_ : $@convention(thin) (@thick ArrayClassReaderWriter.Type) -> @owned ArrayClassReaderWriter
  %4 = metatype $@thick ArrayClassReaderWriter.Type
  %5 = apply %3(%4) : $@convention(thin) (@thick ArrayClassReaderWriter.Type) -> @owned ArrayClassReaderWriter
  store %5 to %2 : $*ArrayClassReaderWriter
  %7 = open_existential_addr %1 : $*ReaderWriterType to $*@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType
  // Check that the type information reaches the witness_method instruction and allows for devirtualization.
  %8 = witness_method $@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType, #ReaderWriterType.read!1, %7 : $*@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType : $@convention(witness_method) <τ_0_0 where τ_0_0 : ReaderWriterType> (Int32, @in_guaranteed τ_0_0) -> Int32
  %9 = integer_literal $Builtin.Int32, 0
  %10 = struct $Int32 (%9 : $Builtin.Int32)
  %11 = apply %8<@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType>(%10, %7) : $@convention(witness_method) <τ_0_0 where τ_0_0 : ReaderWriterType> (Int32, @in_guaranteed τ_0_0) -> Int32
  %12 = integer_literal $Builtin.Int32, 0
  %13 = struct $Int32 (%12 : $Builtin.Int32)
  store %13 to %0 : $*Int32
  destroy_addr %1 : $*ReaderWriterType
  dealloc_stack %1 : $*ReaderWriterType
  dealloc_stack %0 : $*Int32
  return %13 : $Int32
}

// CHECK-LABEL: sil [noinline] @test_existential_type_propagation_via_copy_addr : $@convention(thin) () -> Int32
// CHECK-NOT: init_existential_addr
// CHECK-NOT: copy_addr
// CHECK-NOT: open_existential_addr
// CHECK-NOT: witness_method
// CHECK: function_ref @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_4readuRq_S1__fq_FSiSi : $@convention(witness_method) (Int32, @in_guaranteed ArrayClassReaderWriter) -> Int32
// CHECK: return
sil [noinline] @test_existential_type_propagation_via_copy_addr : $@convention(thin) () -> Int32 {
bb0:
  %0 = alloc_stack $Int32
  %1 = alloc_stack $ReaderWriterType
  %2 = alloc_stack $ReaderWriterType
  // Here we set the concrete type information.
  %3 = init_existential_addr %1 : $*ReaderWriterType, $ArrayClassReaderWriter
  %4 = function_ref @_TFC28existential_type_propagation22ArrayClassReaderWriterCfMS0_FT_S0_ : $@convention(thin) (@thick ArrayClassReaderWriter.Type) -> @owned ArrayClassReaderWriter
  %5 = metatype $@thick ArrayClassReaderWriter.Type
  %6 = apply %4(%5) : $@convention(thin) (@thick ArrayClassReaderWriter.Type) -> @owned ArrayClassReaderWriter
  store %6 to %3 : $*ArrayClassReaderWriter
  // Check that the type information set for %1 is propagated here to %2.
  copy_addr %1 to [initialization] %2 : $*ReaderWriterType
  %9 = open_existential_addr %2 : $*ReaderWriterType to $*@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType
  // Check that the type information reaches the witness_method instruction and allows for devirtualization.
  %10 = witness_method $@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType, #ReaderWriterType.read!1, %9 : $*@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType : $@convention(witness_method) <τ_0_0 where τ_0_0 : ReaderWriterType> (Int32, @in_guaranteed τ_0_0) -> Int32
  %11 = integer_literal $Builtin.Int32, 0
  %12 = struct $Int32 (%11 : $Builtin.Int32)
  %13 = apply %10<@opened("3305E696-5685-11E5-9393-B8E856428C60") ReaderWriterType>(%12, %9) : $@convention(witness_method) <τ_0_0 where τ_0_0 : ReaderWriterType> (Int32, @in_guaranteed τ_0_0) -> Int32
  %14 = integer_literal $Builtin.Int32, 0
  %15 = struct $Int32 (%14 : $Builtin.Int32)
  store %15 to %0 : $*Int32
  destroy_addr %2 : $*ReaderWriterType
  dealloc_stack %2 : $*ReaderWriterType
  destroy_addr %1 : $*ReaderWriterType
  dealloc_stack %1 : $*ReaderWriterType
  dealloc_stack %0 : $*Int32
  return %15 : $Int32
}

protocol P {
	func foo() -> Int64
}

struct X : P {
	var xx : Int64
	func foo() -> Int64
}

// CHECK-LABEL: sil @promote_over_control_flow
// CHECK: bb2:
// CHECK-NOT: open_existential_addr
// CHECK: = function_ref @foo_witness
// CHECK-NEXT: apply
// CHECK-NOT: open_existential_addr
// CHECK: return
sil @promote_over_control_flow : $@convention(thin) () -> Int64 {
bb0:
  %2 = alloc_stack $P, let, name "p"
  %3 = init_existential_addr %2 : $*P, $X
  %6 = integer_literal $Builtin.Int64, 27
  %7 = struct $Int64 (%6 : $Builtin.Int64)
  %8 = struct $X (%7 : $Int64)
  store %8 to %3 : $*X
  cond_br undef, bb1, bb2

bb1:
  br bb2

bb2:
  %10 = open_existential_addr %2 : $*P to $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P
  %11 = witness_method $@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P, #P.foo!1, %10 : $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  %12 = apply %11<@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P>(%10) : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  destroy_addr %2 : $*P
  dealloc_stack %2 : $*P
  return %12 : $Int64
}

// CHECK-LABEL: sil @existential_is_overwritten_by_store
// CHECK: open_existential_addr
// CHECK-NEXT: witness_method
// CHECK-NEXT: apply
sil @existential_is_overwritten_by_store : $@convention(thin) (@in P) -> Int64 {
bb0(%0 : $*P):
  %2 = alloc_stack $P, let, name "p"
  %3 = init_existential_addr %2 : $*P, $X
  %6 = integer_literal $Builtin.Int64, 27
  %7 = struct $Int64 (%6 : $Builtin.Int64)
  %8 = struct $X (%7 : $Int64)
  store %8 to %3 : $*X
  destroy_addr %2 : $*P
  copy_addr [take] %0 to %2 : $*P                 // id: %5
  %10 = open_existential_addr %2 : $*P to $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P
  %11 = witness_method $@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P, #P.foo!1, %10 : $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  %12 = apply %11<@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P>(%10) : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  dealloc_stack %2 : $*P
  return %12 : $Int64
}

// CHECK-LABEL: sil @existential_is_overwritten_by_call
// CHECK: open_existential_addr
// CHECK-NEXT: witness_method
// CHECK-NEXT: apply
// CHECK: return
sil @existential_is_overwritten_by_call : $@convention(thin) () -> Int64 {
bb0:
  %2 = alloc_stack $P, let, name "p"
  %3 = init_existential_addr %2 : $*P, $X
  %6 = integer_literal $Builtin.Int64, 27
  %7 = struct $Int64 (%6 : $Builtin.Int64)
  %8 = struct $X (%7 : $Int64)
  store %8 to %3 : $*X
  destroy_addr %2 : $*P
  %f = function_ref @write_p : $@convention(thin) () -> @out P
  %a = apply %f(%2) : $@convention(thin) () -> @out P
  %10 = open_existential_addr %2 : $*P to $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P
  %11 = witness_method $@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P, #P.foo!1, %10 : $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  %12 = apply %11<@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P>(%10) : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  dealloc_stack %2 : $*P
  return %12 : $Int64
}

// CHECK-LABEL: sil @existential_is_not_overwritten_by_call
// CHECK-NOT: open_existential_addr
// CHECK: = function_ref @foo_witness
// CHECK-NEXT: apply
// CHECK-NOT: open_existential_addr
// CHECK: return
sil @existential_is_not_overwritten_by_call : $@convention(thin) () -> Int64 {
bb0:
  %2 = alloc_stack $P, let, name "p"
  %3 = init_existential_addr %2 : $*P, $X
  %6 = integer_literal $Builtin.Int64, 27
  %7 = struct $Int64 (%6 : $Builtin.Int64)
  %8 = struct $X (%7 : $Int64)
  store %8 to %3 : $*X
  %f = function_ref @read_p : $@convention(thin) (@in P) -> ()
  %a = apply %f(%2) : $@convention(thin) (@in P) -> ()
  %10 = open_existential_addr %2 : $*P to $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P
  %11 = witness_method $@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P, #P.foo!1, %10 : $*@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  %12 = apply %11<@opened("C22498FA-CABF-11E5-B9A9-685B35C48C83") P>(%10) : $@convention(witness_method) <τ_0_0 where τ_0_0 : P> (@in_guaranteed τ_0_0) -> Int64
  destroy_addr %2 : $*P
  dealloc_stack %2 : $*P
  return %12 : $Int64
}

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

sil @read_p : $@convention(thin) (@in P) -> ()

sil @foo_witness : $@convention(witness_method) (@in_guaranteed X) -> Int64

sil_witness_table hidden X: P module nix {
  method #P.foo!1: @foo_witness	
}


sil_vtable ArrayClassReaderWriter {
  #ArrayClassReaderWriter.init!initializer.1: _TFC28existential_type_propagation22ArrayClassReaderWritercfMS0_FT_S0_
}

sil_witness_table public_external ArrayClassReaderWriter: ReaderWriterType module main {
  method #ReaderWriterType.init!allocator.1: @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_CuRq_S1__fMq_FT_q_
  method #ReaderWriterType.read!1: @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_4readuRq_S1__fq_FSiSi
  method #ReaderWriterType.write!1: @_TTWC28existential_type_propagation22ArrayClassReaderWriterS_16ReaderWriterTypeS_FS1_5writeuRq_S1__fRq_FTSi5valueSi_T_
}