Module: MilkTea::Lowering::Utils

Included in:
MilkTea::Lowerer
Defined in:
lib/milk_tea/core/lowering/utils.rb

Instance Method Summary collapse

Instance Method Details

#addressable_storage_expression?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


111
112
113
114
115
116
117
118
119
120
121
122
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 111

def addressable_storage_expression?(expression)
  case expression
  when AST::Identifier
    true
  when AST::MemberAccess, AST::IndexAccess
    addressable_storage_expression?(expression.receiver)
  when AST::Call
    read_call?(expression)
  else
    false
  end
end

#array_element_type(type) ⇒ Object 



49
50
51
52
53
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 49

def array_element_type(type)
  return unless array_type?(type)

  type.arguments.first
end

#array_length(type) ⇒ Object 



88
89
90
91
92
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 88

def array_length(type)
  return unless array_type?(type)

  type.arguments[1].value
end

#array_to_span_compatible?(actual_type, expected_type) ⇒ Boolean

Returns:

  • (Boolean) 


55
56
57
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 55

def array_to_span_compatible?(actual_type, expected_type)
  array_type?(actual_type) && expected_type.is_a?(Types::Span) && array_element_type(actual_type) == expected_type.element_type
end

#array_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


40
41
42
43
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 40

def array_type?(type)
  type.is_a?(Types::GenericInstance) && type.name == "array" && type.arguments.length == 2 &&
    type.arguments[1].is_a?(Types::LiteralTypeArg)
end

#bind_let_else_local?(statement) ⇒ Boolean

Returns:

  • (Boolean) 


818
819
820
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 818

def bind_let_else_local?(statement)
  !let_else_discards_binding?(statement)
end

#c_local_name(name) ⇒ Object 



1126
1127
1128
1129
1130
1131
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1126

def c_local_name(name)
  return "value" unless name
  return "#{name}_" if c_reserved_identifier?(name)

  name
end

#c_reserved_identifier?(identifier) ⇒ Boolean

Returns:

  • (Boolean) 


1133
1134
1135
1136
1137
1138
1139
1140
1141
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1133

def c_reserved_identifier?(identifier)
  %w[
    auto break case char const continue default do double else enum extern
    float for goto if inline int long register restrict return short signed
    sizeof static struct switch typedef union unsigned void volatile while
    _Alignas _Alignof _Atomic _Bool _Complex _Generic _Imaginary _Noreturn
    _Static_assert _Thread_local
  ].include?(identifier)
end

#c_type_name(type) ⇒ Object 



1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1010

def c_type_name(type)
  if type.is_a?(Types::Nullable)
    return "nullable_#{c_type_name(type.base)}"
  end

  if type.respond_to?(:linkage_name) && type.linkage_name
    return type.linkage_name
  end

  if type.is_a?(Types::GenericInstance)
    base = if type.respond_to?(:module_name) && type.module_name&.start_with?("std.c.")
      type.name
    elsif type.respond_to?(:module_name) && !type.module_name.nil?
      "#{module_c_prefix(type.module_name)}_#{type.name}"
    else
      type.name
    end

    return "#{base}_#{sanitize_identifier(type.arguments.join('_'))}"
  end

  return type.name if type.respond_to?(:module_name) && type.module_name&.start_with?("std.c.")

  base = (type.respond_to?(:module_name) && type.module_name) ? "#{module_c_prefix(type.module_name)}_#{type.name}" : type.name
  return base unless type.is_a?(Types::StructInstance) || type.is_a?(Types::VariantInstance)

  "#{base}_#{sanitize_identifier(type.arguments.join('_'))}"
end

#callable_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


466
467
468
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 466

def callable_type?(type)
  type.is_a?(Types::Function) || proc_type?(type)
end

#cfg_block_always_terminates?(statements) ⇒ Boolean

Returns:

  • (Boolean) 


636
637
638
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 636

def cfg_block_always_terminates?(statements)
  ControlFlow::Termination.block_always_terminates?(statements, ignore_name: ->(_name) { false })
end

#char_array_text_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


94
95
96
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 94

def char_array_text_type?(type)
  array_type?(type) && array_element_type(type) == @ctx.types.fetch("char")
end

#cleanup_safe_return_expression?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


1148
1149
1150
1151
1152
1153
1154
1155
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1148

def cleanup_safe_return_expression?(expression)
  case expression
  when AST::IntegerLiteral, AST::FloatLiteral, AST::StringLiteral, AST::BooleanLiteral, AST::NullLiteral
    true
  else
    false
  end
end

#cleanup_statements(local_defers, outer_defers) ⇒ Object 



730
731
732
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 730

def cleanup_statements(local_defers, outer_defers)
  local_defers.reverse.flat_map(&:itself) + outer_defers.reverse.flat_map(&:itself)
end

#collection_loop_binding_type(iterable_type, element_type) ⇒ Object 



162
163
164
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 162

def collection_loop_binding_type(iterable_type, element_type)
  super
end

#collection_loop_item_value(iterable_ref, iterable_type, index_ref, element_type) ⇒ Object 



170
171
172
173
174
175
176
177
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 170

def collection_loop_item_value(iterable_ref, iterable_type, index_ref, element_type)
  if array_type?(iterable_type)
    IR::Index.new(receiver: iterable_ref, index: index_ref, type: element_type)
  else
    data_ref = IR::Member.new(receiver: iterable_ref, member: "data", type: pointer_to(element_type))
    IR::Index.new(receiver: data_ref, index: index_ref, type: element_type)
  end
end

#collection_loop_ref_element_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


166
167
168
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 166

def collection_loop_ref_element_type?(type)
  super
end

#collection_loop_stop_value(iterable_ref, iterable_type) ⇒ Object 



179
180
181
182
183
184
185
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 179

def collection_loop_stop_value(iterable_ref, iterable_type)
  if array_type?(iterable_type)
    IR::IntegerLiteral.new(value: array_length(iterable_type), type: @ctx.types.fetch("ptr_uint"))
  else
    IR::Member.new(receiver: iterable_ref, member: "len", type: @ctx.types.fetch("ptr_uint"))
  end
end

#collection_loop_type(type) ⇒ Object 



158
159
160
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 158

def collection_loop_type(type)
  super
end

#compile_time_builtin_function_type(name, arguments, env) ⇒ Object

Raises:



381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 381

def compile_time_builtin_function_type(name, arguments, env)
  return_type = case name
  when "field_of"
    @ctx.types.fetch("field_handle")
  when "callable_of"
    @ctx.types.fetch("callable_handle")
  when "has_attribute"
    @ctx.types.fetch("bool")
  when "attribute_of"
    @ctx.types.fetch("attribute_handle")
  else
    nil
  end
  raise LoweringError.new("unsupported compile-time builtin #{name}", line: 0, column: 0, path: @ctx.current_analysis_path) unless return_type

  Types::Registry.function(name, params: [], return_type: return_type)
end

#compile_time_builtin_specialization_function_type(callee) ⇒ Object 



399
400
401
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 399

def compile_time_builtin_specialization_function_type(callee)
  Types::Registry.function("attribute_arg", params: [], return_type: resolve_type_ref(callee.arguments.fetch(0).value))
end

#conditional_common_type(then_type, else_type) ⇒ Object 



640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 640

def conditional_common_type(then_type, else_type)
  return then_type if then_type == else_type

  numeric_type = common_numeric_type(then_type, else_type)
  return numeric_type if numeric_type

  if (nullable_type = conditional_null_common_type(then_type, else_type))
    return nullable_type
  end

  if (nullable_type = conditional_null_common_type(else_type, then_type))
    return nullable_type
  end

  return then_type if then_type.is_a?(Types::Nullable) && else_type == then_type.base
  return else_type if else_type.is_a?(Types::Nullable) && then_type == else_type.base

  nil
end

#conditional_null_common_type(null_type, other_type) ⇒ Object 



673
674
675
676
677
678
679
680
681
682
683
684
685
686
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 673

def conditional_null_common_type(null_type, other_type)
  return unless null_type.is_a?(Types::Null)

  if other_type.is_a?(Types::Nullable)
    return other_type if null_type.target_type.nil? || null_type.target_type == other_type.base

    return nil
  end

  return unless nullable_candidate?(other_type)
  return if null_type.target_type && null_type.target_type != other_type

  Types::Registry.nullable(other_type)
end

#contains_label_target?(statements, label) ⇒ Boolean

Returns:

  • (Boolean) 


773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 773

def contains_label_target?(statements, label)
  statements.any? do |statement|
    case statement
    when IR::GotoStmt
      statement.label == label
    when IR::BlockStmt, IR::WhileStmt, IR::ForStmt
      contains_label_target?(statement.body, label)
    when IR::IfStmt
      contains_label_target?(statement.then_body, label) || (statement.else_body && contains_label_target?(statement.else_body, label))
    when IR::SwitchStmt
      statement.cases.any? { |switch_case| contains_label_target?(switch_case.body, label) }
    else
      false
    end
  end
end

#contains_proc_storage_type?(type, visited = Set.new) ⇒ Boolean

Returns:

  • (Boolean) 


470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 470

def contains_proc_storage_type?(type, visited = Set.new)
  return false if visited.include?(type.object_id)

  case type
  when Types::Proc
    true
  when Types::Struct, Types::StructInstance
    visited.add(type.object_id)
    type.fields.each_value.any? { |field_type| contains_proc_storage_type?(field_type, visited) }
  when Types::Nullable
    contains_proc_storage_type?(type.base, visited)
  else
    false
  end
end

#contains_task_type?(type, visited = Set.new) ⇒ Boolean

Returns:

  • (Boolean) 


486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 486

def contains_task_type?(type, visited = Set.new)
  return false if visited.include?(type.object_id)

  case type
  when Types::Task
    true
  when Types::Struct, Types::StructInstance, Types::Union, Types::GenericStructDefinition, Types::VariantArmPayload
    visited.add(type.object_id)
    type.fields.each_value.any? { |ft| contains_task_type?(ft, visited) }
  when Types::VariantInstance
    type.arguments.any? { |arg| contains_task_type?(arg, visited) }
  when Types::Variant, Types::GenericVariantDefinition
    visited.add(type.object_id)
    type.arms.each_value.any? do |arm_fields|
      arm_fields.each_value.any? { |ft| contains_task_type?(ft, visited) }
    end
  when Types::GenericInstance
    type.arguments.any? { |arg| contains_task_type?(arg, visited) }
  when Types::Nullable
    contains_task_type?(type.base, visited)
  else
    false
  end
end

#contains_type_var?(type) ⇒ Boolean

Returns:

  • (Boolean) 


251
252
253
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 251

def contains_type_var?(type)
  super
end

#cstr_list_trackable_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


77
78
79
80
81
82
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 77

def cstr_list_trackable_type?(type)
  return false unless array_type?(type)

  element_type = array_element_type(type)
  element_type == @ctx.types.fetch("str") || element_type == @ctx.types.fetch("cstr")
end

#cstr_trackable_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


59
60
61
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 59

def cstr_trackable_type?(type)
  type == @ctx.types.fetch("str") || type == @ctx.types.fetch("cstr")
end

#current_actual_scope(scopes) ⇒ Object

Raises:



543
544
545
546
547
548
549
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 543

def current_actual_scope(scopes)
  scopes.reverse_each do |scope|
    return scope unless scope.is_a?(FlowScope)
  end

  raise LoweringError.new("missing lexical scope", line: 0, column: 0, path: @ctx.current_analysis_path)
end

#duplicate_env(env) ⇒ Object 



806
807
808
809
810
811
812
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 806

def duplicate_env(env)
  duplicated = env.dup
  duplicated[:scopes] = env[:scopes].map(&:dup) + [{}]
  duplicated[:counter] = env[:counter]
  duplicated.delete(:prepared_expression_cleanups)
  duplicated
end

#empty_env ⇒ Object 



798
799
800
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 798

def empty_env
  { scopes: [{}], counter: { value: 0 } }
end

#enum_member_c_name(type, member_name) ⇒ Object 



1065
1066
1067
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1065

def enum_member_c_name(type, member_name)
  "#{c_type_name(type)}_#{member_name}"
end

#env_with_refinements(env, refinements) ⇒ Object 



551
552
553
554
555
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 551

def env_with_refinements(env, refinements)
  updated = env.dup
  updated[:scopes] = scopes_with_refinements(env[:scopes], refinements)
  updated
end

#external_function_c_name(binding) ⇒ Object 



1082
1083
1084
1085
1086
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1082

def external_function_c_name(binding)
  return binding.ast.mapping.value if binding.external && binding.ast.is_a?(AST::ExternFunctionDecl) && binding.ast.mapping

  binding.name
end

#flow_refinements(expression, truthy:, env:) ⇒ Object 



590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 590

def flow_refinements(expression, truthy:, env:)
  case expression
  when AST::UnaryOp
    return flow_refinements(expression.operand, truthy: !truthy, env:) if expression.operator == "not"
  when AST::BinaryOp
    case expression.operator
    when "and"
      if truthy
        left_truthy = flow_refinements(expression.left, truthy: true, env:)
        right_env = env_with_refinements(env, left_truthy)
        right_truthy = flow_refinements(expression.right, truthy: true, env: right_env)
        return merge_refinements(left_truthy, right_truthy)
      end
    when "or"
      unless truthy
        left_falsy = flow_refinements(expression.left, truthy: false, env:)
        right_env = env_with_refinements(env, left_falsy)
        right_falsy = flow_refinements(expression.right, truthy: false, env: right_env)
        return merge_refinements(left_falsy, right_falsy)
      end
    when "==", "!="
      return null_test_refinements(expression, truthy:, env:)
    end
  end

  {}
end

#forward_declarable_external_opaque?(type) ⇒ Boolean

Returns:

  • (Boolean) 


1049
1050
1051
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1049

def forward_declarable_external_opaque?(type)
  type.external && opaque_forward_declarable?(type)
end

#fresh_c_temp_name(env, prefix) ⇒ Object 



1143
1144
1145
1146
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1143

def fresh_c_temp_name(env, prefix)
  env[:counter][:value] += 1
  "__mt_#{prefix}_#{env[:counter][:value]}"
end

#fresh_proc_symbol ⇒ Object 



539
540
541
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 539

def fresh_proc_symbol
  @synthetic_proc_counter += 1
end

#function_binding_c_name(binding, module_name:, receiver_type: nil) ⇒ Object 



1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1069

def function_binding_c_name(binding, module_name:, receiver_type: nil)
  if receiver_type.nil? && binding.name == "main" && binding.type_arguments.empty?
    return binding.async ? module_function_c_name(module_name, "__async_main") : module_function_c_name(module_name, "main")
  end
  if receiver_type
    base = "#{c_type_name(receiver_type)}_#{binding.name}"
    base = "#{base}_static" if binding.type.receiver_type.nil?
    return binding.type_arguments.empty? ? base : "#{base}__#{generic_type_argument_suffix(binding.type_arguments)}"
  end

  module_function_c_name(module_name, binding.name, type_arguments: binding.type_arguments)
end

#generic_integer_type_argument?(argument) ⇒ Boolean

Returns:

  • (Boolean) 


1061
1062
1063
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1061

def generic_integer_type_argument?(argument)
  integer_type_argument?(argument) || argument.is_a?(Types::TypeVar)
end

#generic_type_argument_suffix(type_arguments) ⇒ Object

Joins resolved generic type arguments into the instance-name suffix used by both the free-function (module_function_c_name) and method (function_binding_c_name) paths, keeping the scheme consistent.



1114
1115
1116
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1114

def generic_type_argument_suffix(type_arguments)
  sanitize_identifier(type_arguments.join('_'))
end

#if_expression_branch_compatible?(actual_type, expected_type) ⇒ Boolean

Returns:

  • (Boolean) 


660
661
662
663
664
665
666
667
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 660

def if_expression_branch_compatible?(actual_type, expected_type)
  return true if actual_type == expected_type
  return true if null_assignable_to?(actual_type, expected_type)
  return true if expected_type.is_a?(Types::Nullable) && actual_type == expected_type.base
  return true if common_numeric_type(actual_type, expected_type) == expected_type

  false
end

#imported_value_c_name(imported_module, name) ⇒ Object 



1092
1093
1094
1095
1096
1097
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1092

def imported_value_c_name(imported_module, name)
  imported_analysis = analysis_for_module(imported_module.name)
  return name if imported_analysis.module_kind == :raw_module

  module_value_c_name(imported_module.name, name)
end

#infer_field_receiver_type(receiver_expression, env:) ⇒ Object 



150
151
152
153
154
155
156
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 150

def infer_field_receiver_type(receiver_expression, env:)
  receiver_type = infer_expression_type(receiver_expression, env:)
  return referenced_type(receiver_type) if ref_type?(receiver_type)
  return pointee_type(receiver_type) if pointer_type?(receiver_type)

  receiver_type
end

#infer_index_result_type(receiver_type, index_type) ⇒ Object

Raises:



223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 223

def infer_index_result_type(receiver_type, index_type)
  raise LoweringError.new("index must be an integer type, got #{index_type}", line: 0, column: 0, path: @ctx.current_analysis_path) unless integer_type?(index_type)

  receiver_type = referenced_type(receiver_type) if ref_type?(receiver_type)

  if array_type?(receiver_type)
    return array_element_type(receiver_type)
  end

  if receiver_type.is_a?(Types::Span)
    return receiver_type.element_type
  end

  if receiver_type.is_a?(Types::SoA)
    return receiver_type.element_type
  end

  if simd_type?(receiver_type)
    return receiver_type.element_type
  end

  if pointer_type?(receiver_type)
    return pointee_type(receiver_type)
  end

  raise LoweringError.new("cannot index #{receiver_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
end

#infer_method_receiver_type(receiver_expression, env:, member_name: nil) ⇒ Object 



136
137
138
139
140
141
142
143
144
145
146
147
148
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 136

def infer_method_receiver_type(receiver_expression, env:, member_name: nil)
  receiver_type = infer_expression_type(receiver_expression, env:)
  receiver_type = referenced_type(receiver_type) if ref_type?(receiver_type)

  if pointer_type?(receiver_type)
    dispatch_receiver_type = method_dispatch_receiver_type(receiver_type)
    return receiver_type if member_name && (@method_definitions.key?([receiver_type, member_name]) || @method_definitions.key?([dispatch_receiver_type, member_name]) || @method_definitions.key?([receiver_type, "static:#{member_name}"]) || @method_definitions.key?([dispatch_receiver_type, "static:#{member_name}"]))

    return pointee_type(receiver_type)
  end

  receiver_type
end

#infer_option_propagation_details(storage_type, env:, allow_void_success:) ⇒ Object

Raises:



994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 994

def infer_option_propagation_details(storage_type, env:, allow_void_success:)
  success_type = let_else_success_type(storage_type)
  raise LoweringError.new("propagation requires a non-void Option success type", line: 0, column: 0, path: @ctx.current_analysis_path) if success_type == @ctx.types.fetch("void") && !allow_void_success

  context = env[:return_context]
  raise LoweringError.new("propagation is only allowed inside function and proc bodies", line: 0, column: 0, path: @ctx.current_analysis_path) unless context
  raise LoweringError.new("propagation is not allowed inside defer blocks", line: 0, column: 0, path: @ctx.current_analysis_path) unless context[:allow_return]

  return_type = context[:return_type]
  unless option_let_else_type?(return_type)
    raise LoweringError.new("propagation requires enclosing function/proc to return Option[_], got #{return_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
  end

  [storage_type, success_type, return_type, nil]
end

#infer_range_loop_type(expression, env:) ⇒ Object

Raises:



200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 200

def infer_range_loop_type(expression, env:)
  start_expr = range_start_of(expression)
  stop_expr = range_end_of(expression)
  start_type = infer_expression_type(start_expr, env:)
  stop_type = infer_expression_type(stop_expr, env:)

  if start_type != stop_type
    if start_expr.is_a?(AST::IntegerLiteral)
      start_type = infer_expression_type(start_expr, env:, expected_type: stop_type)
    elsif stop_expr.is_a?(AST::IntegerLiteral)
      stop_type = infer_expression_type(stop_expr, env:, expected_type: start_type)
    end
  end

  raise LoweringError.new("range bounds must use matching integer types, got #{start_type} and #{stop_type}", line: 0, column: 0, path: @ctx.current_analysis_path) unless start_type == stop_type

  start_type
end

#infer_result_propagation_details(storage_type, env:, allow_void_success:) ⇒ Object

Raises:



972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 972

def infer_result_propagation_details(storage_type, env:, allow_void_success:)
  success_type = let_else_success_type(storage_type)
  error_type = let_else_error_type(storage_type)
  raise LoweringError.new("propagation requires a non-void Result success type", line: 0, column: 0, path: @ctx.current_analysis_path) if success_type == @ctx.types.fetch("void") && !allow_void_success

  context = env[:return_context]
  raise LoweringError.new("propagation is only allowed inside function and proc bodies", line: 0, column: 0, path: @ctx.current_analysis_path) unless context
  raise LoweringError.new("propagation is not allowed inside defer blocks", line: 0, column: 0, path: @ctx.current_analysis_path) unless context[:allow_return]

  return_type = context[:return_type]
  unless result_let_else_type?(return_type)
    raise LoweringError.new("propagation requires enclosing function/proc to return Result[_, #{error_type}], got #{return_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
  end

  return_error_type = let_else_error_type(return_type)
  unless return_error_type == error_type
    raise LoweringError.new("propagation error type #{error_type} must match enclosing Result error type #{return_error_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
  end

  [storage_type, success_type, return_type, error_type]
end

#infer_result_propagation_type(expression, env:) ⇒ Object 



955
956
957
958
959
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 955

def infer_result_propagation_type(expression, env:)
  _storage_type, success_type, = infer_result_propagation_types(expression, env:)

  success_type
end

#infer_result_propagation_types(expression, env:, allow_void_success: false) ⇒ Object 



961
962
963
964
965
966
967
968
969
970
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 961

def infer_result_propagation_types(expression, env:, allow_void_success: false)
  storage_type = infer_expression_type(expression.operand, env:)
  if result_let_else_type?(storage_type)
    infer_result_propagation_details(storage_type, env:, allow_void_success:)
  elsif option_let_else_type?(storage_type)
    infer_option_propagation_details(storage_type, env:, allow_void_success:)
  else
    raise LoweringError.new("propagation expects Result[T, E] or Option[T], got #{storage_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
  end
end

#infer_value_type(handle_expression, env:) ⇒ Object

Raises:



128
129
130
131
132
133
134
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 128

def infer_value_type(handle_expression, env:)
  handle_type = infer_expression_type(handle_expression, env:)
  return referenced_type(handle_type) if ref_type?(handle_type)
  return pointee_type(handle_type) if pointer_type?(handle_type)

  raise LoweringError.new("read expects ref[...] or ptr[...], got #{handle_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
end

#integer_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


219
220
221
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 219

def integer_type?(type)
  type.is_a?(Types::Primitive) && type.integer?
end

#integer_type_argument?(argument) ⇒ Boolean

Returns:

  • (Boolean) 


1057
1058
1059
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1057

def integer_type_argument?(argument)
  argument.is_a?(Types::LiteralTypeArg) && argument.value.is_a?(Integer)
end

#let_else_binding_projection(type) ⇒ Object 



844
845
846
847
848
849
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 844

def let_else_binding_projection(type)
  return :result_success_value if result_let_else_type?(type)
  return :option_some_value if option_let_else_type?(type)

  nil
end

#let_else_discards_binding?(statement) ⇒ Boolean

Returns:

  • (Boolean) 


814
815
816
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 814

def let_else_discards_binding?(statement)
  statement.is_a?(AST::LocalDecl) && statement.else_body && statement.name == "_"
end

#let_else_error_type(type) ⇒ Object 



838
839
840
841
842
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 838

def let_else_error_type(type)
  return unless result_let_else_type?(type)

  type.arm("failure").fetch("error")
end

#let_else_failure_condition(storage_expr, storage_type) ⇒ Object

Raises:



869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 869

def let_else_failure_condition(storage_expr, storage_type)
  if storage_type.is_a?(Types::Nullable)
    return IR::Binary.new(
      operator: "==",
      left: storage_expr,
      right: IR::NullLiteral.new(type: storage_type),
      type: @ctx.types.fetch("bool"),
    )
  end

  if result_let_else_type?(storage_type)
    kind_type = @ctx.types.fetch("int")
    return IR::Binary.new(
      operator: "==",
      left: IR::Member.new(receiver: storage_expr, member: "kind", type: kind_type),
      right: IR::Name.new(name: "#{c_type_name(storage_type)}_kind_failure", type: kind_type, pointer: false),
      type: @ctx.types.fetch("bool"),
    )
  end

  if option_let_else_type?(storage_type)
    kind_type = @ctx.types.fetch("int")
    return IR::Binary.new(
      operator: "==",
      left: IR::Member.new(receiver: storage_expr, member: "kind", type: kind_type),
      right: IR::Name.new(name: "#{c_type_name(storage_type)}_kind_none", type: kind_type, pointer: false),
      type: @ctx.types.fetch("bool"),
    )
  end

  raise LoweringError.new("unsupported let-else storage type #{storage_type}", line: 0, column: 0, path: @ctx.current_analysis_path)
end

#let_else_storage_c_name(statement, env) ⇒ Object 



822
823
824
825
826
827
828
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 822

def let_else_storage_c_name(statement, env)
  return fresh_c_temp_name(env, "let_else_discard") if let_else_discards_binding?(statement)

  return fresh_c_temp_name(env, "_") if statement.name == "_"

  c_local_name(statement.name)
end

#let_else_success_type(type) ⇒ Object 



830
831
832
833
834
835
836
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 830

def let_else_success_type(type)
  return type.base if type.is_a?(Types::Nullable)
  return type.arm("some").fetch("value") if option_let_else_type?(type)
  return unless result_let_else_type?(type)

  type.arm("success").fetch("value")
end

#local_binding(type:, linkage_name:, mutable:, pointer:, storage_type: nil, projection: nil, cstr_backed: false, cstr_list_backed: false, const_value: nil) ⇒ Object 



462
463
464
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 462

def local_binding(type:, linkage_name:, mutable:, pointer:, storage_type: nil, projection: nil, cstr_backed: false, cstr_list_backed: false, const_value: nil)
  { type:, storage_type: storage_type || type, linkage_name:, mutable:, pointer:, projection:, cstr_backed:, cstr_list_backed:, const_value: }
end

#lookup_value(name, env) ⇒ Object 



299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 299

def lookup_value(name, env)
  env[:scopes].reverse_each do |scope|
    return scope[name] if scope.key?(name)
  end

  if @ctx.values.key?(name)
    binding = @ctx.values.fetch(name)
    {
      type: binding.type,
      storage_type: binding.storage_type,
      linkage_name: value_c_name(name),
      mutable: binding.mutable,
      pointer: false,
      cstr_backed: cstr_trackable_type?(binding.type) && binding.const_value.is_a?(String),
      cstr_list_backed: false,
      const_value: binding.const_value,
    }
  end
end

#loop_exit_break(label = nil) ⇒ Object 



734
735
736
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 734

def loop_exit_break(label = nil)
  { kind: :break, label: }
end

#loop_exit_continue(label = nil) ⇒ Object 



738
739
740
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 738

def loop_exit_continue(label = nil)
  { kind: :continue, label: }
end

#loop_exit_label(label) ⇒ Object 



742
743
744
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 742

def loop_exit_label(label)
  { kind: :label, label: }
end

#loop_exit_statement(target, local_defers:, outer_defers:) ⇒ Object 



746
747
748
749
750
751
752
753
754
755
756
757
758
759
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 746

def loop_exit_statement(target, local_defers:, outer_defers:)
  case target[:kind]
  when :break
    IR::BreakStmt.new
  when :continue
    IR::ContinueStmt.new
  when :label
    return IR::GotoStmt.new(label: target[:label]) if target[:label]

    IR::GotoStmt.new(label: target[:label])
  else
    raise LoweringError.new("unsupported loop exit target #{target.inspect}", line: 0, column: 0, path: @ctx.current_analysis_path)
  end
end

#loop_flow(break_target:, continue_target:, break_defers: [], continue_defers: []) ⇒ Object 



692
693
694
695
696
697
698
699
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 692

def loop_flow(break_target:, continue_target:, break_defers: [], continue_defers: [])
  {
    break_target:,
    continue_target:,
    break_defers:,
    continue_defers:,
  }
end

#lower_assignment_binding_target(binding) ⇒ Object 



1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1217

def lower_assignment_binding_target(binding)
  storage_type = binding[:storage_type]
  visible_type = binding[:type]
  storage_ref = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])

  case binding[:projection]
  when :result_success_value
    variant_binding_projection_expression(storage_ref, storage_type, "success", "value", visible_type)
  when :option_some_value
    variant_binding_projection_expression(storage_ref, storage_type, "some", "value", visible_type)
  else
    if visible_type == storage_type || (storage_type.is_a?(Types::Nullable) && storage_type.base == visible_type)
      IR::Name.new(name: binding[:linkage_name], type: visible_type, pointer: binding[:pointer])
    else
      storage_ref
    end
  end
end

#lower_assignment_target(expression, env:) ⇒ Object 



1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1168

def lower_assignment_target(expression, env:)
  case expression
  when AST::Identifier
    binding = lookup_value(expression.name, env)
    lower_assignment_binding_target(binding)
  when AST::MemberAccess
    if expression.receiver.is_a?(AST::IndexAccess)
      base_type = infer_expression_type(expression.receiver.receiver, env:)
      if base_type.is_a?(Types::SoA)
        soa_base = lower_expression(expression.receiver.receiver, env:)
        index = lower_expression(expression.receiver.index, env:)
        field_type = base_type.fields[expression.member]
        target_type = infer_expression_type(expression, env:)
        return IR::Index.new(
          receiver: IR::Member.new(receiver: soa_base, member: expression.member, type: field_type),
          index:,
          type: target_type,
        )
      end
    end
    receiver_type = infer_expression_type(expression.receiver, env:)
    receiver = lower_expression(expression.receiver, env:)
    type = infer_expression_type(expression, env:)
    IR::Member.new(receiver:, member: member_c_name(receiver_type, expression.member), type:)
  when AST::IndexAccess
    receiver_type = infer_expression_type(expression.receiver, env:)
    receiver = lower_expression(expression.receiver, env:)
    index = lower_expression(expression.index, env:)
    type = infer_expression_type(expression, env:)
    if array_type?(receiver_type)
      IR::CheckedIndex.new(receiver:, index:, receiver_type:, type:)
    elsif receiver_type.is_a?(Types::Span)
      IR::CheckedSpanIndex.new(receiver:, index:, receiver_type:, type:)
    else
      IR::Index.new(receiver:, index:, type:)
    end
  when AST::Call
    if read_call?(expression)
      type = infer_expression_type(expression, env:)
      operand = lower_expression(expression.arguments.first.value, env:)
      return IR::Unary.new(operator: "*", operand:, type:)
    end

    raise LoweringError.new("unsupported assignment target #{expression.class.name}", line: 0, column: 0, path: @ctx.current_analysis_path)
  else
    raise LoweringError.new("unsupported assignment target #{expression.class.name}", line: 0, column: 0, path: @ctx.current_analysis_path)
  end
end

#lower_bound_identifier(binding, expected_type: nil) ⇒ Object 



902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 902

def lower_bound_identifier(binding, expected_type: nil)
  storage_type = binding[:storage_type]
  visible_type = binding[:type]
  projection = binding[:projection]

  if projection == :result_success_value
    local_ref = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])
    return variant_binding_projection_expression(local_ref, storage_type, "success", "value", visible_type)
  end

  if projection == :result_failure_error
    local_ref = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])
    return variant_binding_projection_expression(local_ref, storage_type, "failure", "error", visible_type)
  end

  if projection == :option_some_value
    local_ref = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])
    return variant_binding_projection_expression(local_ref, storage_type, "some", "value", visible_type)
  end

  return IR::Name.new(name: binding[:linkage_name], type: visible_type, pointer: binding[:pointer]) if visible_type == storage_type
  if storage_type.is_a?(Types::Nullable) && storage_type.base == visible_type
    name = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])
    return name if pointer_like_type?(storage_type.base)
    return name if expected_type == storage_type
    return IR::Member.new(receiver: name, member: "value", type: visible_type)
  end

  if result_let_else_type?(storage_type) && let_else_success_type(storage_type) == visible_type
    local_ref = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])
    return variant_binding_projection_expression(local_ref, storage_type, "success", "value", visible_type)
  end

  if option_let_else_type?(storage_type) && let_else_success_type(storage_type) == visible_type
    local_ref = IR::Name.new(name: binding[:linkage_name], type: storage_type, pointer: binding[:pointer])
    return variant_binding_projection_expression(local_ref, storage_type, "some", "value", visible_type)
  end

  IR::Name.new(name: binding[:linkage_name], type: visible_type, pointer: binding[:pointer])
end

#lower_compile_time_literal(value, type) ⇒ Object 



345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 345

def lower_compile_time_literal(value, type)
  case value
  when true, false
    return IR::BooleanLiteral.new(value:, type:) if type.is_a?(Types::Primitive) && type.boolean?
  when Integer
    return IR::IntegerLiteral.new(value:, type:) if type.is_a?(Types::Primitive) && type.integer?
    return IR::FloatLiteral.new(value: value.to_f, type:) if type.is_a?(Types::Primitive) && type.float?
  when Float
    return IR::FloatLiteral.new(value:, type:) if type.is_a?(Types::Primitive) && type.float?
  when String
    if type == @ctx.types.fetch("str") || type == @ctx.types.fetch("cstr")
      return IR::StringLiteral.new(value:, type:, cstring: type == @ctx.types.fetch("cstr"))
    end
  when Array
    return nil unless array_type?(type)

    element_type = type.arguments.first
    elements = value.map { |element| lower_compile_time_literal(element, element_type) }
    return nil if elements.any?(&:nil?)

    IR::ArrayLiteral.new(type:, elements:)
  when Hash
    return nil unless type.is_a?(Types::Struct)
    fields = value.map do |name, field_value|
      field_type = type.field(name)
      return nil unless field_type
      lowered = lower_compile_time_literal(field_value, field_type)
      return nil unless lowered
      IR::AggregateField.new(name:, value: lowered)
    end
    return IR::AggregateLiteral.new(type:, fields:)
  end

  nil
end

#lower_defer_cleanup_body(statements, env:, return_type:) ⇒ Object 



790
791
792
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 790

def lower_defer_cleanup_body(statements, env:, return_type:)
  lower_block(statements, env:, active_defers: [], return_type:, loop_flow: nil, allow_return: false)
end

#lower_fatal_statement(message, env:) ⇒ Object 



187
188
189
190
191
192
193
194
195
196
197
198
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 187

def lower_fatal_statement(message, env:)
  IR::ExpressionStmt.new(
    expression: lower_expression(
      AST::Call.new(
        callee: AST::Identifier.new(name: "fatal"),
        arguments: [AST::Argument.new(name: nil, value: AST::StringLiteral.new(lexeme: message.inspect, value: message, cstring: false))],
      ),
      env:,
      expected_type: @ctx.types.fetch("void"),
    ),
  )
end

#lower_loop_exit(target, local_defers, outer_defers) ⇒ Object 



761
762
763
764
765
766
767
768
769
770
771
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 761

def lower_loop_exit(target, local_defers, outer_defers)
  cleanup = cleanup_statements(local_defers, outer_defers)
  if cleanup.empty?
    [loop_exit_statement(target, local_defers:, outer_defers:)]
  else
    label = target[:label]
    raise LoweringError.new("structured loop exits with cleanup are unsupported", line: 0, column: 0, path: @ctx.current_analysis_path) unless label

    cleanup + [IR::GotoStmt.new(label:)]
  end
end

#lower_range_match_condition(range_pattern, scrutinee_ir, bool_type, env:) ⇒ Object 



10
11
12
13
14
15
16
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 10

def lower_range_match_condition(range_pattern, scrutinee_ir, bool_type, env:)
  start_ir = lower_expression(range_pattern.start_expr, env:, expected_type: nil)
  end_ir   = lower_expression(range_pattern.end_expr, env:, expected_type: nil)
  ge = IR::Binary.new(operator: ">=", left: scrutinee_ir, right: start_ir, type: bool_type)
  le = IR::Binary.new(operator: "<=", left: scrutinee_ir, right: end_ir, type: bool_type)
  IR::Binary.new(operator: "and", left: ge, right: le, type: bool_type)
end

#lower_static_storage_initializer(expression, env:, expected_type: nil) ⇒ Object 



319
320
321
322
323
324
325
326
327
328
329
330
331
332
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 319

def lower_static_storage_initializer(expression, env:, expected_type: nil)
  if expected_type && (literal = lower_compile_time_literal(compile_time_const_value(expression, env:), expected_type))
    return literal
  end

  rewritten = rewrite_static_storage_initializer(expression)
  if (imported_analysis = static_storage_imported_analysis(expression))
    with_analysis_context(imported_analysis) do
      lower_expression(rewritten, env:, expected_type: expected_type)
    end
  else
    lower_expression(rewritten, env:, expected_type: expected_type)
  end
end

#merge_refinements(existing, incoming) ⇒ Object 



577
578
579
580
581
582
583
584
585
586
587
588
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 577

def merge_refinements(existing, incoming)
  merged = existing.dup
  incoming.each do |name, refined_type|
    if merged.key?(name) && merged[name] != refined_type
      merged.delete(name)
    else
      merged[name] = refined_type
    end
  end

  merged
end

#module_c_prefix(module_name) ⇒ Object 



1122
1123
1124
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1122

def module_c_prefix(module_name)
  sanitize_identifier(module_name.to_s.tr('.', '_'))
end

#module_function_c_name(module_name, name, type_arguments: []) ⇒ Object 



1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1099

def module_function_c_name(module_name, name, type_arguments: [])
  base = "#{module_c_prefix(module_name)}_#{name}"
  return base if type_arguments.empty?

  # A double-underscore separates a generic function instance's type
  # arguments so it cannot collide with a distinct regular function whose
  # name happens to be `<name>_<typearg>` (e.g. the instance
  # `expect_equal[str]` vs the function `expect_equal_str`). The method path
  # in `function_binding_c_name` uses the same scheme for consistency.
  "#{base}__#{generic_type_argument_suffix(type_arguments)}"
end

#module_value_c_name(module_name, name) ⇒ Object 



1118
1119
1120
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1118

def module_value_c_name(module_name, name)
  "#{module_c_prefix(module_name)}_#{name}"
end

#nested_loop_flow(current_loop_flow, local_defers) ⇒ Object 



701
702
703
704
705
706
707
708
709
710
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 701

def nested_loop_flow(current_loop_flow, local_defers)
  return nil unless current_loop_flow

  loop_flow(
    break_target: current_loop_flow[:break_target],
    continue_target: current_loop_flow[:continue_target],
    break_defers: current_loop_flow[:break_defers] + local_defers,
    continue_defers: current_loop_flow[:continue_defers] + local_defers,
  )
end

#null_test_refinements(expression, truthy:, env:) ⇒ Object 



618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 618

def null_test_refinements(expression, truthy:, env:)
  identifier_expression = nil
  if expression.left.is_a?(AST::Identifier) && expression.right.is_a?(AST::NullLiteral)
    identifier_expression = expression.left
  elsif expression.left.is_a?(AST::NullLiteral) && expression.right.is_a?(AST::Identifier)
    identifier_expression = expression.right
  else
    return {}
  end

  binding = lookup_value(identifier_expression.name, env)
  return {} unless binding && binding[:storage_type].is_a?(Types::Nullable)

  null_result = expression.operator == "==" ? truthy : !truthy
  refined_type = null_result ? null_type : binding[:storage_type].base
  { identifier_expression.name => refined_type }
end

#null_type ⇒ Object 



688
689
690
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 688

def null_type
  @null_type ||= Types::Null.new
end

#nullable_candidate?(type) ⇒ Boolean

Returns:

  • (Boolean) 


669
670
671
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 669

def nullable_candidate?(type)
  !ref_type?(type) && type != @ctx.types.fetch("void")
end

#nullable_some_literal(nullable_type, value) ⇒ Object 



1244
1245
1246
1247
1248
1249
1250
1251
1252
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1244

def nullable_some_literal(nullable_type, value)
  IR::AggregateLiteral.new(
    type: nullable_type,
    fields: [
      IR::AggregateField.new(name: "has_value", value: IR::BooleanLiteral.new(value: true, type: @ctx.types.fetch("bool"))),
      IR::AggregateField.new(name: "value", value:),
    ],
  )
end

#opaque_c_type_name(type) ⇒ Object 



1039
1040
1041
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1039

def opaque_c_type_name(type)
  type.linkage_name || c_type_name(type)
end

#opaque_forward_declarable?(type) ⇒ Boolean

Returns:

  • (Boolean) 


1043
1044
1045
1046
1047
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1043

def opaque_forward_declarable?(type)
  return false unless opaque_c_type_name(type).match?(/\A[A-Za-z_][A-Za-z0-9_]*\z/)

  !type.external || type.linkage_name.nil?
end

#option_let_else_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


851
852
853
854
855
856
857
858
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 851

def option_let_else_type?(type)
  return false unless type.is_a?(Types::Variant)

  some_fields = type.arm("some")
  none_fields = type.arm("none")
  some_fields && some_fields.length == 1 && some_fields.key?("value") &&
    none_fields && none_fields.empty?
end

#pointer_like_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


1254
1255
1256
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1254

def pointer_like_type?(type)
  pointer_type?(type) || own_type?(type) || (type.is_a?(Types::Primitive) && type.name == "cstr") || type.is_a?(Types::Function) || type.is_a?(Types::Proc) || type.is_a?(Types::Opaque)
end

#pointer_to(type) ⇒ Object 



286
287
288
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 286

def pointer_to(type)
  Types::Registry.generic_instance("ptr", [type])
end

#proc_env_pointer_type ⇒ Object 



511
512
513
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 511

def proc_env_pointer_type
  @proc_env_pointer_type ||= pointer_to(@ctx.types.fetch("void"))
end

#proc_invoke_function_type(proc_type) ⇒ Object 



515
516
517
518
519
520
521
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 515

def proc_invoke_function_type(proc_type)
  Types::Registry.function(
    nil,
    params: [Types::Registry.parameter("env", proc_env_pointer_type), *proc_type.params],
    return_type: proc_type.return_type,
  )
end

#proc_release_function_type ⇒ Object 



523
524
525
526
527
528
529
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 523

def proc_release_function_type
  @proc_release_function_type ||= Types::Registry.function(
    nil,
    params: [Types::Registry.parameter("env", proc_env_pointer_type)],
    return_type: @ctx.types.fetch("void"),
  )
end

#proc_retain_function_type ⇒ Object 



531
532
533
534
535
536
537
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 531

def proc_retain_function_type
  @proc_retain_function_type ||= Types::Registry.function(
    nil,
    params: [Types::Registry.parameter("env", proc_env_pointer_type)],
    return_type: @ctx.types.fetch("void"),
  )
end

#range_end_of(iterable) ⇒ Object 



22
23
24
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 22

def range_end_of(iterable)
  iterable.end_expr
end

#range_iterable?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


6
7
8
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 6

def range_iterable?(expression)
  range_expr?(expression)
end

#range_start_of(iterable) ⇒ Object 



18
19
20
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 18

def range_start_of(iterable)
  iterable.start_expr
end

#read_call?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


124
125
126
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 124

def read_call?(expression)
  expression.is_a?(AST::Call) && expression.callee.is_a?(AST::Identifier) && expression.callee.name == "read"
end

#reject_format_releases_for_assignment(cleanups, target_type) ⇒ Object 



69
70
71
72
73
74
75
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 69

def reject_format_releases_for_assignment(cleanups, target_type)
  return cleanups unless cstr_trackable_type?(target_type) || struct_contains_string_field?(target_type)

  cleanups.reject do |items|
    items.any? { |stmt| stmt.is_a?(IR::ExpressionStmt) && stmt.expression.is_a?(IR::Call) && stmt.expression.callee == "mt_format_str_release" }
  end
end

#result_let_else_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


860
861
862
863
864
865
866
867
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 860

def result_let_else_type?(type)
  return false unless type.is_a?(Types::Variant)

  success_fields = type.arm("success")
  failure_fields = type.arm("failure")
  success_fields && success_fields.length == 1 && success_fields.key?("value") &&
    failure_fields && failure_fields.length == 1 && failure_fields.key?("error")
end

#rewrite_static_storage_initializer(expression) ⇒ Object 



403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 403

def rewrite_static_storage_initializer(expression)
  case expression
  when AST::Identifier
    binding = @ctx.values[expression.name]
    if binding&.kind == :const
      declaration = const_declaration_for_module(@ctx.module_name, expression.name)
      return rewrite_static_storage_initializer(declaration.value)
    end

    expression
  when AST::MemberAccess
    if expression.receiver.is_a?(AST::Identifier) && @ctx.imports.key?(expression.receiver.name)
      imported_module = @ctx.imports.fetch(expression.receiver.name)
      if (binding = imported_module.values[expression.member])&.kind == :const
        imported_analysis = analysis_for_module(imported_module.name)
        declaration = const_declaration_for_module(imported_module.name, expression.member)
        return with_analysis_context(imported_analysis) do
          rewrite_static_storage_initializer(declaration.value)
        end
      end
    end

    AST::MemberAccess.new(
      receiver: rewrite_static_storage_initializer(expression.receiver),
      member: expression.member,
    )
  when AST::UnaryOp
    AST::UnaryOp.new(operator: expression.operator, operand: rewrite_static_storage_initializer(expression.operand))
  when AST::BinaryOp
    AST::BinaryOp.new(
      operator: expression.operator,
      left: rewrite_static_storage_initializer(expression.left),
      right: rewrite_static_storage_initializer(expression.right),
    )
  when AST::IfExpr
    AST::IfExpr.new(
      condition: rewrite_static_storage_initializer(expression.condition),
      then_expression: rewrite_static_storage_initializer(expression.then_expression),
      else_expression: rewrite_static_storage_initializer(expression.else_expression),
    )
  when AST::UnsafeExpr
    AST::UnsafeExpr.new(expression: rewrite_static_storage_initializer(expression.expression))
  when AST::Call
    AST::Call.new(
      callee: rewrite_static_storage_initializer(expression.callee),
      arguments: expression.arguments.map do |argument|
        AST::Argument.new(name: argument.name, value: rewrite_static_storage_initializer(argument.value))
      end,
    )
  when AST::Specialization
    AST::Specialization.new(
      callee: rewrite_static_storage_initializer(expression.callee),
      arguments: expression.arguments.map { |argument| AST::TypeArgument.new(value: argument.value) },
    )
  else
    expression
  end
end

#sanitize_identifier(text) ⇒ Object 



1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1157

def sanitize_identifier(text)
  return "value" unless text

  cache = (@sanitize_identifier_cache ||= {})
  cached = cache[text]
  return cached if cached

  identifier = text.gsub(/[^A-Za-z0-9_]+/, "_").gsub(/_+/, "_").sub(/_+$/, "").sub(/^_+/, "")
  cache[text] = identifier.empty? ? "value" : identifier
end

#scopes_with_refinements(scopes, refinements) ⇒ Object 



557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 557

def scopes_with_refinements(scopes, refinements)
  return scopes if refinements.nil? || refinements.empty?

  base_scopes = scopes.last.is_a?(FlowScope) ? scopes[0...-1] : scopes
  merged_refinements = scopes.last.is_a?(FlowScope) ? scopes.last.each_with_object({}) { |(name, binding), result| result[name] = binding[:type] } : {}
  merged_refinements = merge_refinements(merged_refinements, refinements)
  flow_scope = FlowScope.new

  merged_refinements.each do |name, refined_type|
    binding = lookup_value(name, { scopes: base_scopes })
    next unless binding

    flow_scope[name] = binding.merge(type: refined_type)
  end

  return base_scopes if flow_scope.empty?

  base_scopes + [flow_scope]
end

#simd_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


45
46
47
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 45

def simd_type?(type)
  type.is_a?(Types::Simd)
end

#snapshot_env(env) ⇒ Object 



802
803
804
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 802

def snapshot_env(env)
  { scopes: env[:scopes].map(&:dup), counter: env[:counter] }
end

#static_storage_imported_analysis(expression) ⇒ Object 



334
335
336
337
338
339
340
341
342
343
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 334

def static_storage_imported_analysis(expression)
  return nil unless expression.is_a?(AST::MemberAccess)
  return nil unless expression.receiver.is_a?(AST::Identifier)
  return nil unless @ctx.imports.key?(expression.receiver.name)

  imported_module = @ctx.imports.fetch(expression.receiver.name)
  return nil unless imported_module.values[expression.member]&.kind == :const

  analysis_for_module(imported_module.name)
end

#stored_ref_supported_type?(type, visited = {}) ⇒ Boolean

Returns:

  • (Boolean) 


256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 256

def stored_ref_supported_type?(type, visited = {})
  return true unless type

  visit_key = [type.class, type.object_id]
  return true if visited[visit_key]

  visited[visit_key] = true
  case type
  when Types::Nullable
    stored_ref_supported_type?(type.base, visited)
  when Types::GenericInstance
    if ref_type?(type)
      lt = ref_lifetime(type)
      return !!lt  # lifetime-ref is supported by default; bare ref is not
    end

    type.arguments.all? { |argument| argument.is_a?(Types::LiteralTypeArg) || stored_ref_supported_type?(argument, visited) }
  when Types::Span
    stored_ref_supported_type?(type.element_type, visited)
  when Types::Task
    stored_ref_supported_type?(type.result_type, visited)
  when Types::StructInstance, Types::VariantInstance
    type.arguments.all? { |argument| stored_ref_supported_type?(argument, visited) }
  when Types::Proc, Types::Function
    callable_param_ref_supported?(type)
  else
    !contains_ref_type?(type)
  end
end

#str_buffer_capacity(type) ⇒ Object 



103
104
105
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 103

def str_buffer_capacity(type)
  type.arguments.first.value
end

#str_buffer_storage_capacity(type) ⇒ Object 



107
108
109
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 107

def str_buffer_storage_capacity(type)
  str_buffer_capacity(type) + 1
end

#str_buffer_to_span_compatible?(actual_type, expected_type) ⇒ Boolean

Returns:

  • (Boolean) 


84
85
86
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 84

def str_buffer_to_span_compatible?(actual_type, expected_type)
  str_buffer_type?(actual_type) && expected_type.is_a?(Types::Span) && expected_type.element_type == @ctx.types.fetch("char")
end

#str_buffer_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


98
99
100
101
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 98

def str_buffer_type?(type)
  type.is_a?(Types::GenericInstance) && type.name == "str_buffer" && type.arguments.length == 1 &&
    type.arguments.first.is_a?(Types::LiteralTypeArg) && type.arguments.first.value.is_a?(Integer)
end

#struct_contains_string_field?(type) ⇒ Boolean

Returns:

  • (Boolean) 


63
64
65
66
67
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 63

def struct_contains_string_field?(type)
  return false unless type.is_a?(Types::Struct)

  type.fields.any? { |_name, field_type| cstr_trackable_type?(field_type) || struct_contains_string_field?(field_type) }
end

#switch_loop_flow(current_loop_flow, local_defers) ⇒ Object 



718
719
720
721
722
723
724
725
726
727
728
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 718

def switch_loop_flow(current_loop_flow, local_defers)
  nested = nested_loop_flow(current_loop_flow, local_defers)
  return nil unless nested

  loop_flow(
    break_target: switch_loop_target(nested[:break_target]),
    continue_target: switch_loop_target(nested[:continue_target]),
    break_defers: nested[:break_defers],
    continue_defers: nested[:continue_defers],
  )
end

#switch_loop_target(target) ⇒ Object 



712
713
714
715
716
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 712

def switch_loop_target(target)
  return target unless target && target[:label]

  loop_exit_label(target[:label])
end

#terminating_ir_statement?(statement) ⇒ Boolean

Returns:

  • (Boolean) 


794
795
796
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 794

def terminating_ir_statement?(statement)
  statement.is_a?(IR::ReturnStmt) || statement.is_a?(IR::GotoStmt)
end

#validate_generic_type!(name, arguments) ⇒ Object 



1053
1054
1055
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1053

def validate_generic_type!(name, arguments)
  super(name, arguments) { |msg| raise LoweringError.new(msg, line: 0, column: 0, path: @ctx.current_analysis_path) }
end

#value_c_name(name) ⇒ Object 



1088
1089
1090
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1088

def value_c_name(name)
  module_value_c_name(@ctx.module_name, name)
end

#variant_binding_projection_expression(storage_expr, storage_type, arm_name, field_name, field_type) ⇒ Object 



943
944
945
946
947
948
949
950
951
952
953
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 943

def variant_binding_projection_expression(storage_expr, storage_type, arm_name, field_name, field_type)
  payload_type = Types::VariantArmPayload.new(storage_type, arm_name, storage_type.arm(arm_name))
  data_expr = IR::Member.new(receiver: storage_expr, member: "data", type: nil)
  arm_expr = IR::Member.new(receiver: data_expr, member: arm_name, type: payload_type)
  member_expr = IR::Member.new(receiver: arm_expr, member: field_name, type: field_type)
  if type_reaches_target?(field_type, payload_type.variant_type)
    return IR::Unary.new(operator: "*", operand: member_expr, type: field_type)
  end

  member_expr
end

#variant_match_arm_name_from_pattern(pattern) ⇒ Object 



30
31
32
33
34
35
36
37
38
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 30

def variant_match_arm_name_from_pattern(pattern)
  callee = case pattern
  when AST::Call
    pattern.callee
  else
    pattern
  end
  callee.is_a?(AST::MemberAccess) ? callee.member : nil
end

#wildcard_arm_pattern?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


26
27
28
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 26

def wildcard_arm_pattern?(expression)
  expression.is_a?(AST::Identifier) && expression.name == "_"
end

#with_analysis_context(analysis) ⇒ Object 



290
291
292
293
294
295
296
297
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 290

def with_analysis_context(analysis)
  saved = @ctx.save
  @ctx.install(analysis)
  @ctx.module_prefix = module_c_prefix(@ctx.module_name)
  yield
ensure
  @ctx.restore(saved)
end

#wrap_nullable_field_value(field_type, lowered_value, env) ⇒ Object 



1236
1237
1238
1239
1240
1241
1242
 
# File 'lib/milk_tea/core/lowering/utils.rb', line 1236

def wrap_nullable_field_value(field_type, lowered_value, env)
  return lowered_value unless field_type.is_a?(Types::Nullable)
  return lowered_value if pointer_like_type?(field_type.base)
  return lowered_value if lowered_value.type.is_a?(Types::Nullable)

  nullable_some_literal(field_type, lowered_value)
end