Module: MilkTea::LowererUtils

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

Instance Method Summary collapse

Instance Method Details

#addressable_storage_expression?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 110

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 48

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

  type.arguments.first
end

#array_length(type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 87

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 54

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 39

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) 


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

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

#c_local_name(name) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1099

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

  identifier
end

#c_reserved_identifier?(identifier) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1107

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 983

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 439

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

#cfg_block_always_terminates?(statements) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 609

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 93

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) 


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

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 703

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 161

def collection_loop_binding_type(iterable_type, element_type)
  super
end

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



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# File 'lib/milk_tea/core/lowering/utils.rb', line 169

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 165

def collection_loop_ref_element_type?(type)
  super
end

#collection_loop_stop_value(iterable_ref, iterable_type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 178

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 157

def collection_loop_type(type)
  super
end

#compile_time_builtin_function_type(name, arguments, env) ⇒ Object

Raises:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 354

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 372

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 613

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 646

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 746

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 443

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 459

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 250

def contains_type_var?(type)
  super
end

#cstr_list_trackable_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 76

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 58

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

#current_actual_scope(scopes) ⇒ Object

Raises:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 516

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 779

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 771

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

#enum_member_c_name(type, member_name) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1038

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

#env_with_refinements(env, refinements) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 524

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 



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

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 563

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1022

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

#fresh_c_temp_name(env, prefix) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1117

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

#fresh_proc_symbol ⇒ Object 



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

def fresh_proc_symbol
  @synthetic_proc_counter += 1
end

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



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1042

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1034

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.



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1087

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

#if_expression_branch_compatible?(actual_type, expected_type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 633

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 



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

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 149

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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 222

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 135

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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 967

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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 199

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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 945

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 928

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 934

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

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# File 'lib/milk_tea/core/lowering/utils.rb', line 127

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 218

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

#integer_type_argument?(argument) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1030

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

#let_else_binding_projection(type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 817

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_discard_binding_syntax?(statement) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 787

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

#let_else_error_type(type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 811

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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 842

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 



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

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

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

  c_local_name(statement.name)
end

#let_else_success_type(type) ⇒ Object 



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

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 435

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 298

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 707

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

#loop_exit_continue(label = nil) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 711

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

#loop_exit_label(label) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 715

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

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



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# File 'lib/milk_tea/core/lowering/utils.rb', line 719

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 665

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1191

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1142

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 875

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 326

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 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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 763

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 186

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 



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

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 9

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 318

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

  lower_expression(rewrite_static_storage_initializer(expression), env:, expected_type: expected_type)
end

#merge_refinements(existing, incoming) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 550

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1095

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

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



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1072

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1091

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

#nested_loop_flow(current_loop_flow, local_defers) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 674

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 591

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 661

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

#nullable_candidate?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 642

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

#nullable_some_literal(nullable_type, value) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1218

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1012

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

#opaque_forward_declarable?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1016

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 824

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1228

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 285

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

#proc_env_pointer_type ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 484

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

#proc_invoke_function_type(proc_type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 488

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 496

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 504

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 21

def range_end_of(iterable)
  iterable.end_expr
end

#range_iterable?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 5

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

#range_start_of(iterable) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 17

def range_start_of(iterable)
  iterable.start_expr
end

#read_call?(expression) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 123

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

#result_let_else_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 833

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 376

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1131

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 530

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 44

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

#snapshot_env(env) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 775

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

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

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 255

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 102

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

#str_buffer_storage_capacity(type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 106

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

#str_buffer_to_span_compatible?(actual_type, expected_type) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 83

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 97

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 62

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

#suppress_format_releases_for_assignment(cleanups, target_type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 68

def suppress_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

#switch_loop_flow(current_loop_flow, local_defers) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 691

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 685

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

  loop_exit_label(target[:label])
end

#terminating_ir_statement?(statement) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 767

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

#validate_generic_type!(name, arguments) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1026

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 



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

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 916

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 29

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 25

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

#with_analysis_context(analysis) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 289

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1210

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