Module: MilkTea::CBackend::Reinterpret

Included in:
MilkTea::CBackend
Defined in:
lib/milk_tea/core/c_backend/reinterpret.rb

Instance Method Summary collapse

Instance Method Details

#c_operator(operator) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 231

def c_operator(operator)
  operator == "and" ? "&&" : operator == "or" ? "||" : operator
end

#callable_container_element_type?(type) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 153

def callable_container_element_type?(type)
  type.is_a?(Types::Function) || type.is_a?(Types::Proc)
end

#checked_array_index_helper_name(type) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 129

def checked_array_index_helper_name(type)
  return "mt_checked_index_array_#{sanitize_identifier(c_declaration(array_element_type(type), 'value'))}_#{array_length(type)}" if array_type?(type) && callable_container_element_type?(array_element_type(type))

  "mt_checked_index_#{sanitize_identifier(type.to_s)}"
end

#checked_span_index_helper_name(type) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 135

def checked_span_index_helper_name(type)
  return "mt_checked_span_index_#{sanitize_identifier(c_declaration(type.element_type, 'value'))}" if callable_container_element_type?(type.element_type)

  "mt_checked_span_index_#{sanitize_identifier(type.to_s)}"
end

#collect_reinterpret_helpersObject



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 6

def collect_reinterpret_helpers
  helpers = []
  seen = {}

  emitted_functions.each do |function|
    collect_reinterpret_helpers_from_statements(function.body, helpers, seen)
  end

  helpers
end

#collect_reinterpret_helpers_from_expression(expression, helpers, seen) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 55

def collect_reinterpret_helpers_from_expression(expression, helpers, seen)
  case expression
  when IR::Member
    collect_reinterpret_helpers_from_expression(expression.receiver, helpers, seen)
  when IR::Index, IR::CheckedIndex, IR::CheckedSpanIndex, IR::NullableIndex, IR::NullableSpanIndex
    collect_reinterpret_helpers_from_expression(expression.receiver, helpers, seen)
    collect_reinterpret_helpers_from_expression(expression.index, helpers, seen)
  when IR::Call
    collect_reinterpret_helpers_from_expression(expression.callee, helpers, seen) unless expression.callee.is_a?(String)
    expression.arguments.each { |argument| collect_reinterpret_helpers_from_expression(argument, helpers, seen) }
  when IR::Unary
    collect_reinterpret_helpers_from_expression(expression.operand, helpers, seen)
  when IR::Binary
    collect_reinterpret_helpers_from_expression(expression.left, helpers, seen)
    collect_reinterpret_helpers_from_expression(expression.right, helpers, seen)
  when IR::Conditional
    collect_reinterpret_helpers_from_expression(expression.condition, helpers, seen)
    collect_reinterpret_helpers_from_expression(expression.then_expression, helpers, seen)
    collect_reinterpret_helpers_from_expression(expression.else_expression, helpers, seen)
  when IR::ReinterpretExpr
    return if no_op_reinterpret?(expression.target_type, expression.source_type)

    key = [expression.target_type, expression.source_type]
    unless seen[key]
      helpers << expression
      seen[key] = true
    end
    collect_reinterpret_helpers_from_expression(expression.expression, helpers, seen)
  when IR::AddressOf
    collect_reinterpret_helpers_from_expression(expression.expression, helpers, seen)
  when IR::Cast
    collect_reinterpret_helpers_from_expression(expression.expression, helpers, seen)
  when IR::AggregateLiteral
    expression.fields.each { |field| collect_reinterpret_helpers_from_expression(field.value, helpers, seen) }
  when IR::ArrayLiteral
    expression.elements.each { |element| collect_reinterpret_helpers_from_expression(element, helpers, seen) }
  when IR::VariantLiteral
    expression.fields.each { |field| collect_reinterpret_helpers_from_expression(field.value, helpers, seen) }
  when IR::ZeroInit, IR::IntegerLiteral, IR::FloatLiteral, IR::StringLiteral, IR::BooleanLiteral, IR::NullLiteral, IR::Name, IR::SizeofExpr, IR::AlignofExpr, IR::OffsetofExpr
    nil
  end
end

#collect_reinterpret_helpers_from_statements(statements, helpers, seen) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 17

def collect_reinterpret_helpers_from_statements(statements, helpers, seen)
  statements.each do |statement|
    case statement
    when IR::LocalDecl
      collect_reinterpret_helpers_from_expression(statement.value, helpers, seen)
    when IR::Assignment
      collect_reinterpret_helpers_from_expression(statement.target, helpers, seen)
      collect_reinterpret_helpers_from_expression(statement.value, helpers, seen)
    when IR::BlockStmt
      collect_reinterpret_helpers_from_statements(statement.body, helpers, seen)
    when IR::WhileStmt
      collect_reinterpret_helpers_from_expression(statement.condition, helpers, seen)
      collect_reinterpret_helpers_from_statements(statement.body, helpers, seen)
    when IR::ForStmt
      collect_reinterpret_helpers_from_statements([statement.init], helpers, seen)
      collect_reinterpret_helpers_from_expression(statement.condition, helpers, seen)
      collect_reinterpret_helpers_from_statements(statement.body, helpers, seen)
      collect_reinterpret_helpers_from_statements([statement.post], helpers, seen)
    when IR::IfStmt
      collect_reinterpret_helpers_from_expression(statement.condition, helpers, seen)
      collect_reinterpret_helpers_from_statements(statement.then_body, helpers, seen)
      collect_reinterpret_helpers_from_statements(statement.else_body, helpers, seen) if statement.else_body
    when IR::SwitchStmt
      collect_reinterpret_helpers_from_expression(statement.expression, helpers, seen)
      statement.cases.each do |switch_case|
        collect_reinterpret_helpers_from_statements(switch_case.body, helpers, seen)
      end
    when IR::StaticAssert
      collect_reinterpret_helpers_from_expression(statement.condition, helpers, seen)
      collect_reinterpret_helpers_from_expression(statement.message, helpers, seen)
    when IR::ReturnStmt
      collect_reinterpret_helpers_from_expression(statement.value, helpers, seen) if statement.value
    when IR::ExpressionStmt
      collect_reinterpret_helpers_from_expression(statement.expression, helpers, seen)
    end
  end
end

#emit_reinterpret_helper(expression) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 98

def emit_reinterpret_helper(expression)
  helper_name = reinterpret_helper_name(expression.target_type, expression.source_type)
  params = c_declaration(expression.source_type, 'value')
  [
    "static inline #{c_function_declaration(expression.target_type, helper_name, params)} {",
    "#{INDENT}_Static_assert(sizeof(#{layout_type_expression(expression.target_type)}) == sizeof(#{layout_type_expression(expression.source_type)}), \"reinterpret requires equal sizes\");",
    "#{INDENT}#{c_declaration(expression.target_type, 'result')};",
    "#{INDENT}memcpy(&result, &value, sizeof(result));",
    "#{INDENT}return result;",
    "}",
  ]
end

#no_op_cast?(expression) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 115

def no_op_cast?(expression)
  return false if expression.expression.type.is_a?(Types::Null)

  c_type(expression.target_type) == c_type(expression.expression.type)
rescue StandardError
  false
end

#no_op_reinterpret?(target_type, source_type) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 123

def no_op_reinterpret?(target_type, source_type)
  c_type(target_type) == c_type(source_type)
rescue StandardError
  false
end

#nullable_array_index_helper_name(type) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 141

def nullable_array_index_helper_name(type)
  return "mt_nullable_index_array_#{sanitize_identifier(c_declaration(array_element_type(type), 'value'))}_#{array_length(type)}" if array_type?(type) && callable_container_element_type?(array_element_type(type))

  "mt_nullable_index_#{sanitize_identifier(type.to_s)}"
end

#nullable_pointer_like_ir_type?(type) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 199

def nullable_pointer_like_ir_type?(type)
  return false unless type.is_a?(Types::Nullable)

  c_backend_pointer_like_type?(type.base)
end

#nullable_span_index_helper_name(type) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 147

def nullable_span_index_helper_name(type)
  return "mt_nullable_span_index_#{sanitize_identifier(c_declaration(type.element_type, 'value'))}" if callable_container_element_type?(type.element_type)

  "mt_nullable_span_index_#{sanitize_identifier(type.to_s)}"
end

#pointer_member_receiver?(expression) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 174

def pointer_member_receiver?(expression)
  return true if checked_index_alias(expression)
  return pointer_member_receiver?(expression.operand) if expression.is_a?(IR::Unary) && expression.operator == "*"

  if expression.is_a?(IR::Member)
    field_type = variant_arm_payload_field_type(expression)
    if field_type && expression.receiver.type.is_a?(Types::VariantArmPayload)
      parent_c = named_type_c_name(expression.receiver.type.variant_type)
      return true if aggregate_field_creates_cycle?(field_type, parent_c)
    end
  end

  (expression.is_a?(IR::Name) && expression.pointer) ||
    (expression.respond_to?(:type) && (raw_pointer_type?(expression.type) || ref_type?(expression.type) || nullable_pointer_like_ir_type?(expression.type)))
end

#reinterpret_helper_name(target_type, source_type) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 111

def reinterpret_helper_name(target_type, source_type)
  "mt_reinterpret_#{sanitize_identifier(target_type.to_s)}_from_#{sanitize_identifier(source_type.to_s)}"
end

#variant_arm_payload_field_type(member_expr) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 190

def variant_arm_payload_field_type(member_expr)
  receiver_type = member_expr.receiver.type
  return nil unless receiver_type.is_a?(Types::VariantArmPayload)

  arm_name = receiver_type.arm_name
  variant_type = receiver_type.variant_type
  variant_type.arm(arm_name)&.fetch(member_expr.member)
end

#void_typeObject



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 235

def void_type
  @void_type ||= Types::Registry.primitive("void")
end

#wrap_index_receiver(expression) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 216

def wrap_index_receiver(expression)
  case expression
  when IR::CheckedIndex, IR::CheckedSpanIndex, IR::NullableIndex, IR::NullableSpanIndex
    if (alias_name = checked_index_alias(expression))
      "(*#{alias_name})"
    else
      emit_expression(expression)
    end
  when IR::Name, IR::Member, IR::Index, IR::Call
    emit_expression(expression)
  else
    "(#{emit_expression(expression)})"
  end
end

#wrap_member_receiver(expression) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 157

def wrap_member_receiver(expression)
  case expression
  when IR::Unary
    if expression.operator == "*"
      wrap_pointer_member_receiver(expression.operand)
    else
      "(#{emit_expression(expression)})"
    end
  when IR::CheckedIndex, IR::CheckedSpanIndex, IR::NullableIndex, IR::NullableSpanIndex
    checked_index_alias(expression) || emit_expression(expression)
  when IR::Name, IR::Member, IR::Index
    emit_expression(expression)
  else
    "(#{emit_expression(expression)})"
  end
end

#wrap_pointer_member_receiver(expression) ⇒ Object



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# File 'lib/milk_tea/core/c_backend/reinterpret.rb', line 205

def wrap_pointer_member_receiver(expression)
  case expression
  when IR::CheckedIndex, IR::CheckedSpanIndex, IR::NullableIndex, IR::NullableSpanIndex
    checked_index_alias(expression) || emit_expression(expression)
  when IR::Name, IR::Member, IR::Index, IR::Call
    emit_expression(expression)
  else
    "(#{emit_expression(expression)})"
  end
end