test/SILOptimizer/cast_foldings.sil

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

import Swift

class AClass {
  deinit
  init()
}

struct S {}

@objc class NSCloud {}

// CHECK-LABEL: sil @dont_fold_unconditional_checked_cast_to_existentials
// CHECK: unconditional_checked_cast %1 : $NSCloud to $AnyObject
sil @dont_fold_unconditional_checked_cast_to_existentials : $@convention(thin) () -> AnyObject {
entry:
  %0 = alloc_stack $NSCloud
  %1 = load %0#1 : $*NSCloud
  %2 = unconditional_checked_cast %1 : $NSCloud to $AnyObject
  dealloc_stack %0#0 : $*@local_storage NSCloud
  return %2 : $AnyObject
}

// CHECK-LABEL: sil @dont_fold_unconditional_checked_cast_from_existentials
// CHECK: unconditional_checked_cast %0 : $AnyObject to $NSCloud
sil @dont_fold_unconditional_checked_cast_from_existentials : $@convention(thin) (AnyObject) -> NSCloud {
entry (%0 : $AnyObject):
  %1 = unconditional_checked_cast %0 : $AnyObject to $NSCloud
  return %1 : $NSCloud
}

// CHECK-LABEL: sil @function_cast_nothrow_to_nothrow
// CHECK:         load
// CHECK:         store
sil @function_cast_nothrow_to_nothrow : $@convention(thin) <T> () -> () {
entry:
  %a = unconditional_checked_cast_addr take_on_success () -> ()        in undef : $*(@out (), @in ()) -> ()                 to () -> ()        in undef : $*(@out (), @in ()) -> ()
  return undef : $()
}

// CHECK-LABEL: sil @function_cast_nothrow_to_nothrow_substitutable
// CHECK:         unconditional_checked_cast_addr
sil @function_cast_nothrow_to_nothrow_substitutable : $@convention(thin) <T> () -> () {
entry:
  %a = unconditional_checked_cast_addr take_on_success () -> ()        in undef : $*(@out (), @in ()) -> ()                 to T -> T        in undef : $*(@out T, @in T) -> ()
  return undef : $()
}

// CHECK-LABEL: sil @function_cast_nothrow_substitutable_to_nothrow
// CHECK:         unconditional_checked_cast_addr
sil @function_cast_nothrow_substitutable_to_nothrow : $@convention(thin) <T> () -> () {
entry:
  %a = unconditional_checked_cast_addr take_on_success T -> T        in undef : $*(@out T, @in T) -> ()                 to () -> ()        in undef : $*(@out (), @in ()) -> ()
  return undef : $()
}

// CHECK-LABEL: sil @function_cast_throw_to_nothrow
// CHECK:         builtin "int_trap"
sil @function_cast_throw_to_nothrow : $@convention(thin) <T> () -> () {
  %b = unconditional_checked_cast_addr take_on_success () throws -> () in undef : $*(@out (), @in ()) -> (@error ErrorType) to () -> ()        in undef : $*(@out (), @in ()) -> ()
  return undef : $()
}

// TODO: Do a function_conversion?
// CHECK-LABEL: sil @function_cast_nothrow_to_throw
// CHECK:         unconditional_checked_cast_addr
sil @function_cast_nothrow_to_throw : $@convention(thin) <T> () -> () {
  %c = unconditional_checked_cast_addr take_on_success () -> ()        in undef : $*(@out (), @in ()) -> ()                 to () throws -> () in undef : $*(@out (), @in ()) -> (@error ErrorType)
  return undef : $()
}

// CHECK-LABEL: sil @function_cast_throw_to_throw
// CHECK:         load
// CHECK:         store
sil @function_cast_throw_to_throw : $@convention(thin) <T> () -> () {
  %d = unconditional_checked_cast_addr take_on_success () throws -> () in undef : $*(@out (), @in ()) -> (@error ErrorType) to () throws -> () in undef : $*(@out (), @in ()) -> (@error ErrorType)
  return undef : $()
}

// CHECK-LABEL: sil @function_ref_cast_promote
// CHECK: [[LD:%.*]] = load %1 : $*AnyObject
// CHECK-NEXT: unchecked_ref_cast [[LD]] : $AnyObject to $AClass
// CHECK-NEXT: store %{{.*}} to %0 : $*AClass
sil @function_ref_cast_promote : $@convention(thin) (@out AClass, @in AnyObject) -> () {
bb0(%0 : $*AClass, %1 : $*AnyObject):
  unchecked_ref_cast_addr  AnyObject in %1 : $*AnyObject to AClass in %0 : $*AClass
  %4 = tuple ()
  return %4 : $()
}

// Do not promote a ref cast for invalid types. It's a runtime error.
// CHECK-LABEL: sil @function_ref_cast_struct
// CHECK: unchecked_ref_cast_addr
sil @function_ref_cast_struct : $@convention(thin) () -> @owned AnyObject {
bb0:
  %0 = struct $S ()
  %1 = alloc_stack $S
  store %0 to %1#1 : $*S
  %4 = alloc_stack $AnyObject
  unchecked_ref_cast_addr  S in %1#1 : $*S to AnyObject in %4#1 : $*AnyObject
  %6 = load %4#1 : $*AnyObject
  dealloc_stack %4#0 : $*@local_storage AnyObject
  dealloc_stack %1#0 : $*@local_storage S
  return %6 : $AnyObject
}