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) 


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# 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 



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# 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 



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# 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) 


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# 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) 


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# 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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 801

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

#c_local_name(name) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1113

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) 


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

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 997

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 449

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 619

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 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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 1135

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 713

def cleanup_statements(local_defers, outer_defers)
  local_defers.reverse.flat_map(&:itself) + outer_defers.reverse.flat_map(&:itself)
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 158

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_stop_value(iterable_ref, iterable_type) ⇒ Object 



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

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

#compile_time_builtin_function_type(name, arguments, env) ⇒ Object

Raises:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 364

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 382

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 623

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 656

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 756

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 453

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 469

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

#cstr_list_trackable_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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# 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) 


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# 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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 526

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 789

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 781

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 1052

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 534

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 1069

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 573

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 1036

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 1130

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 522

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 1056

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 1048

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 1101

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 643

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 1079

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 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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 211

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 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:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 981

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 188

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 959

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 942

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 948

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 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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 207

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 1044

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 827

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 797

def let_else_discards_binding?(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 821

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 852

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 805

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 813

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, substitute_const_value: false) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 445

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

#lookup_value(name, env) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 282

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 717

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 721

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 725

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 729

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 675

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 1204

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 1155

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 885

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

  if binding[:substitute_const_value] && !binding[:const_value].nil?
    return lower_const_value_literal(visible_type, binding[:const_value])
  end

  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 328

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 773

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 175

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 744

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 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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 302

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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 560

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 1109

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 1086

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 1105

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 684

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 601

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 671

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 652

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 1231

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 1026

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 1030

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 834

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 1241

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 269

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 494

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 498

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 506

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 514

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 22

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 6

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 18

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 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 



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# 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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 843

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 386

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 1144

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 540

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 45

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 785

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

#static_storage_imported_analysis(expression) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 317

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) 


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# File 'lib/milk_tea/core/lowering/utils.rb', line 239

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 103

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 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) 


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# 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) 


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# 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) 


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# 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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 701

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 695

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 777

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 1040

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 1075

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 930

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 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) 


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# 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 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 273

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 1223

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