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 792

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 1100

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 1108

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 984

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 440

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 610

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 1123

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 704

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 162

def collection_loop_binding_type(iterable_type, element_type)
  super
end

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



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# File 'lib/milk_tea/core/lowering/utils.rb', line 170

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

#collection_loop_ref_element_type?(type) ⇒ Boolean

Returns:

  • (Boolean) 


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

def collection_loop_ref_element_type?(type)
  super
end

#collection_loop_stop_value(iterable_ref, iterable_type) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 179

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

#collection_loop_type(type) ⇒ Object 



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

def collection_loop_type(type)
  super
end

#compile_time_builtin_function_type(name, arguments, env) ⇒ Object

Raises:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 355

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 373

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 614

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 647

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 747

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 444

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 460

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 251

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 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 517

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 780

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 772

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 1039

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 525

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 1056

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 564

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 1023

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 1118

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 513

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 1043

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 1035

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 1088

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 634

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 1066

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 223

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

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

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

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

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

  if simd_type?(receiver_type)
    return receiver_type.element_type
  end

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

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

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



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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 968

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

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# File 'lib/milk_tea/core/lowering/utils.rb', line 200

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

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

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

  start_type
end

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

Raises:



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# File 'lib/milk_tea/core/lowering/utils.rb', line 946

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 929

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 935

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 219

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 1031

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 818

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 788

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 812

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 843

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 796

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 804

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 436

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 299

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

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

#loop_exit_break(label = nil) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 708

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 712

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 716

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 720

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 666

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 1192

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 1143

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 876

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 327

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 764

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 187

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

#lower_loop_exit(target, local_defers, outer_defers) ⇒ Object 



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

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 319

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

  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 551

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 1096

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 1073

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 1092

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 675

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 592

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 662

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 643

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 1219

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 1013

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 1017

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 825

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 1229

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 286

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 485

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 489

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 497

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 505

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 834

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 377

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 1132

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 531

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 776

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 256

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

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

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

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

#str_buffer_capacity(type) ⇒ Object 



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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 692

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 686

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 768

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 1027

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 1062

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 917

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 290

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

#wrap_nullable_field_value(field_type, lowered_value, env) ⇒ Object 



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# File 'lib/milk_tea/core/lowering/utils.rb', line 1211

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