ruby--ruby/test/ruby/test_yjit.rb

# frozen_string_literal: true
#
# This set of tests can be run with:
# make test-all TESTS='test/ruby/test_yjit.rb' RUN_OPTS="--yjit-call-threshold=1"

require 'test/unit'
require 'envutil'
require 'tmpdir'
require_relative '../lib/jit_support'

return unless defined?(RubyVM::YJIT) && RubyVM::YJIT.enabled?

# Tests for YJIT with assertions on compilation and side exits
# insipired by the MJIT tests in test/ruby/test_mjit.rb
class TestYJIT < Test::Unit::TestCase
  def test_yjit_in_ruby_description
    assert_includes(RUBY_DESCRIPTION, '+YJIT')
  end

  # Check that YJIT is in the version string
  def test_yjit_in_version
    [
      %w(--version --yjit),
      %w(--version --disable-yjit --yjit),
      %w(--version --disable-yjit --enable-yjit),
      %w(--version --disable-yjit --enable=yjit),
      %w(--version --disable=yjit --yjit),
      %w(--version --disable=yjit --enable-yjit),
      %w(--version --disable=yjit --enable=yjit),
      *([
        %w(--version --jit),
        %w(--version --disable-jit --jit),
        %w(--version --disable-jit --enable-jit),
        %w(--version --disable-jit --enable=jit),
        %w(--version --disable=jit --yjit),
        %w(--version --disable=jit --enable-jit),
        %w(--version --disable=jit --enable=jit),
      ] if JITSupport.yjit_supported?),
    ].each do |version_args|
      assert_in_out_err(version_args) do |stdout, stderr|
        assert_equal(RUBY_DESCRIPTION, stdout.first)
        assert_equal([], stderr)
      end
    end
  end

  def test_command_line_switches
    assert_in_out_err('--yjit-', '', [], /invalid option --yjit-/)
    assert_in_out_err('--yjithello', '', [], /invalid option --yjithello/)
    #assert_in_out_err('--yjit-call-threshold', '', [], /--yjit-call-threshold needs an argument/)
    #assert_in_out_err('--yjit-call-threshold=', '', [], /--yjit-call-threshold needs an argument/)
  end

  def test_yjit_stats_and_v_no_error
    _stdout, stderr, _status = EnvUtil.invoke_ruby(%w(-v --yjit-stats), '', true, true)
    refute_includes(stderr, "NoMethodError")
  end

  def test_enable_from_env_var
    yjit_child_env = {'RUBY_YJIT_ENABLE' => '1'}
    assert_in_out_err([yjit_child_env, '--version'], '') do |stdout, stderr|
      assert_equal(RUBY_DESCRIPTION, stdout.first)
      assert_equal([], stderr)
    end
    assert_in_out_err([yjit_child_env, '-e puts RUBY_DESCRIPTION'], '', [RUBY_DESCRIPTION])
    assert_in_out_err([yjit_child_env, '-e p RubyVM::YJIT.enabled?'], '', ['true'])
  end

  def test_compile_setclassvariable
    script = 'class Foo; def self.foo; @@foo = 1; end; end; Foo.foo'
    assert_compiles(script, insns: %i[setclassvariable], result: 1)
  end

  def test_compile_getclassvariable
    script = 'class Foo; @@foo = 1; def self.foo; @@foo; end; end; Foo.foo'
    assert_compiles(script, insns: %i[getclassvariable], result: 1)
  end

  def test_compile_putnil
    assert_compiles('nil', insns: %i[putnil], result: nil)
  end

  def test_compile_putobject
    assert_compiles('true', insns: %i[putobject], result: true)
    assert_compiles('123', insns: %i[putobject], result: 123)
    assert_compiles(':foo', insns: %i[putobject], result: :foo)
  end

  def test_compile_opt_succ
    assert_compiles('1.succ', insns: %i[opt_succ], result: 2)
  end

  def test_compile_opt_not
    assert_compiles('!false', insns: %i[opt_not], result: true)
    assert_compiles('!nil', insns: %i[opt_not], result: true)
    assert_compiles('!true', insns: %i[opt_not], result: false)
    assert_compiles('![]', insns: %i[opt_not], result: false)
  end

  def test_compile_opt_newarray
    assert_compiles('[]', insns: %i[newarray], result: [])
    assert_compiles('[1+1]', insns: %i[newarray opt_plus], result: [2])
    assert_compiles('[1,1+1,3,4,5,6]', insns: %i[newarray opt_plus], result: [1, 2, 3, 4, 5, 6])
  end

  def test_compile_opt_duparray
    assert_compiles('[1]', insns: %i[duparray], result: [1])
    assert_compiles('[1, 2, 3]', insns: %i[duparray], result: [1, 2, 3])
  end

  def test_compile_newrange
    assert_compiles('s = 1; (s..5)', insns: %i[newrange], result: 1..5)
    assert_compiles('s = 1; e = 5; (s..e)', insns: %i[newrange], result: 1..5)
    assert_compiles('s = 1; (s...5)', insns: %i[newrange], result: 1...5)
    assert_compiles('s = 1; (s..)', insns: %i[newrange], result: 1..)
    assert_compiles('e = 5; (..e)', insns: %i[newrange], result: ..5)
  end

  def test_compile_duphash
    assert_compiles('{ two: 2 }', insns: %i[duphash], result: { two: 2 })
  end

  def test_compile_newhash
    assert_compiles('{}', insns: %i[newhash], result: {})
    assert_compiles('{ two: 1 + 1 }', insns: %i[newhash], result: { two: 2 })
    assert_compiles('{ 1 + 1 => :two }', insns: %i[newhash], result: { 2 => :two })
  end

  def test_compile_opt_nil_p
    assert_compiles('nil.nil?', insns: %i[opt_nil_p], result: true)
    assert_compiles('false.nil?', insns: %i[opt_nil_p], result: false)
    assert_compiles('true.nil?', insns: %i[opt_nil_p], result: false)
    assert_compiles('(-"").nil?', insns: %i[opt_nil_p], result: false)
    assert_compiles('123.nil?', insns: %i[opt_nil_p], result: false)
  end

  def test_compile_eq_fixnum
    assert_compiles('123 == 123', insns: %i[opt_eq], result: true)
    assert_compiles('123 == 456', insns: %i[opt_eq], result: false)
  end

  def test_compile_eq_string
    assert_compiles('-"" == -""', insns: %i[opt_eq], result: true)
    assert_compiles('-"foo" == -"foo"', insns: %i[opt_eq], result: true)
    assert_compiles('-"foo" == -"bar"', insns: %i[opt_eq], result: false)
  end

  def test_compile_eq_symbol
    assert_compiles(':foo == :foo', insns: %i[opt_eq], result: true)
    assert_compiles(':foo == :bar', insns: %i[opt_eq], result: false)
    assert_compiles(':foo == "foo".to_sym', insns: %i[opt_eq], result: true)
  end

  def test_compile_eq_object
    assert_compiles(<<~RUBY, insns: %i[opt_eq], result: false)
      def eq(a, b)
        a == b
      end

      eq(Object.new, Object.new)
    RUBY

    assert_compiles(<<~RUBY, insns: %i[opt_eq], result: true)
      def eq(a, b)
        a == b
      end

      obj = Object.new
      eq(obj, obj)
    RUBY
  end

  def test_compile_eq_arbitrary_class
    assert_compiles(<<~RUBY, insns: %i[opt_eq], result: "yes")
      def eq(a, b)
        a == b
      end

      class Foo
        def ==(other)
          "yes"
        end
      end

      eq(Foo.new, Foo.new)
      eq(Foo.new, Foo.new)
    RUBY
  end

  def test_compile_opt_lt
    assert_compiles('1 < 2', insns: %i[opt_lt])
    assert_compiles('"a" < "b"', insns: %i[opt_lt])
  end

  def test_compile_opt_le
    assert_compiles('1 <= 2', insns: %i[opt_le])
    assert_compiles('"a" <= "b"', insns: %i[opt_le])
  end

  def test_compile_opt_gt
    assert_compiles('1 > 2', insns: %i[opt_gt])
    assert_compiles('"a" > "b"', insns: %i[opt_gt])
  end

  def test_compile_opt_ge
    assert_compiles('1 >= 2', insns: %i[opt_ge])
    assert_compiles('"a" >= "b"', insns: %i[opt_ge])
  end

  def test_compile_opt_plus
    assert_compiles('1 + 2', insns: %i[opt_plus])
    assert_compiles('"a" + "b"', insns: %i[opt_plus])
    assert_compiles('[:foo] + [:bar]', insns: %i[opt_plus])
  end

  def test_compile_opt_minus
    assert_compiles('1 - 2', insns: %i[opt_minus])
    assert_compiles('[:foo, :bar] - [:bar]', insns: %i[opt_minus])
  end

  def test_compile_opt_or
    assert_compiles('1 | 2', insns: %i[opt_or])
    assert_compiles('[:foo] | [:bar]', insns: %i[opt_or])
  end

  def test_compile_opt_and
    assert_compiles('1 & 2', insns: %i[opt_and])
    assert_compiles('[:foo, :bar] & [:bar]', insns: %i[opt_and])
  end

  def test_compile_set_and_get_global
    assert_compiles('$foo = 123; $foo', insns: %i[setglobal], result: 123)
  end

  def test_compile_putspecialobject
    assert_compiles('-> {}', insns: %i[putspecialobject])
  end

  def test_compile_tostring
    assert_no_exits('"i am a string #{true}"')
  end

  def test_compile_opt_aset
    assert_compiles('[1,2,3][2] = 4', insns: %i[opt_aset])
    assert_compiles('{}[:foo] = :bar', insns: %i[opt_aset])
    assert_compiles('[1,2,3][0..-1] = []', insns: %i[opt_aset])
    assert_compiles('"foo"[3] = "d"', insns: %i[opt_aset])
  end

  def test_compile_attr_set
    assert_no_exits(<<~EORB)
    class Foo
      attr_accessor :bar
    end

    foo = Foo.new
    foo.bar = 3
    foo.bar = 3
    foo.bar = 3
    foo.bar = 3
    EORB
  end

  def test_compile_regexp
    assert_no_exits('/#{true}/')
  end

  def test_compile_dynamic_symbol
    assert_compiles(':"#{"foo"}"', insns: %i[intern])
    assert_compiles('s = "bar"; :"foo#{s}"', insns: %i[intern])
  end

  def test_getlocal_with_level
    assert_compiles(<<~RUBY, insns: %i[getlocal opt_plus], result: [[7]])
      def foo(foo, bar)
        [1].map do |x|
          [1].map do |y|
            foo + bar
          end
        end
      end

      foo(5, 2)
    RUBY
  end

  def test_setlocal_with_level
    assert_no_exits(<<~RUBY)
      def sum(arr)
        sum = 0
        arr.each do |x|
          sum += x
        end
        sum
      end

      sum([1,2,3])
    RUBY
  end

  def test_string_then_nil
    assert_compiles(<<~RUBY, insns: %i[opt_nil_p], result: true)
      def foo(val)
        val.nil?
      end

      foo("foo")
      foo(nil)
    RUBY
  end

  def test_nil_then_string
    assert_compiles(<<~RUBY, insns: %i[opt_nil_p], result: false)
      def foo(val)
        val.nil?
      end

      foo(nil)
      foo("foo")
    RUBY
  end

  def test_string_concat_utf8
    assert_compiles(<<~RUBY, frozen_string_literal: true, result: true)
      def str_cat_utf8
        s = String.new
        10.times { s << "✅" }
        s
      end

      str_cat_utf8 == "✅" * 10
    RUBY
  end

  def test_string_concat_ascii
    # Constant-get for classes (e.g. String, Encoding) can cause a side-exit in getinlinecache. For now, ignore exits.
    assert_compiles(<<~RUBY, exits: :any)
      str_arg = "b".encode(Encoding::ASCII)
      def str_cat_ascii(arg)
        s = String.new(encoding: Encoding::ASCII)
        10.times { s << arg }
        s
      end

      str_cat_ascii(str_arg) == str_arg * 10
    RUBY
  end

  def test_opt_length_in_method
    assert_compiles(<<~RUBY, insns: %i[opt_length], result: 5)
      def foo(str)
        str.length
      end

      foo("hello, ")
      foo("world")
    RUBY
  end

  def test_opt_regexpmatch2
    assert_compiles(<<~RUBY, insns: %i[opt_regexpmatch2], result: 0)
      def foo(str)
        str =~ /foo/
      end

      foo("foobar")
    RUBY
  end

  def test_expandarray
    assert_compiles(<<~'RUBY', insns: %i[expandarray], result: [1, 2])
      a, b = [1, 2]
    RUBY
  end

  def test_expandarray_nil
    assert_compiles(<<~'RUBY', insns: %i[expandarray], result: [nil, nil])
      a, b = nil
      [a, b]
    RUBY
  end

  def test_getspecial_backref
    assert_compiles("'foo' =~ /(o)./; $&", insns: %i[getspecial], result: "oo")
    assert_compiles("'foo' =~ /(o)./; $`", insns: %i[getspecial], result: "f")
    assert_compiles("'foo' =~ /(o)./; $'", insns: %i[getspecial], result: "")
    assert_compiles("'foo' =~ /(o)./; $+", insns: %i[getspecial], result: "o")
    assert_compiles("'foo' =~ /(o)./; $1", insns: %i[getspecial], result: "o")
    assert_compiles("'foo' =~ /(o)./; $2", insns: %i[getspecial], result: nil)
  end

  def test_compile_opt_getconstant_path
    assert_compiles(<<~RUBY, insns: %i[opt_getconstant_path], result: 123, call_threshold: 2)
      def get_foo
        FOO
      end

      FOO = 123

      get_foo # warm inline cache
      get_foo
    RUBY
  end

  def test_opt_getconstant_path_slowpath
    assert_compiles(<<~RUBY, exits: { opt_getconstant_path: 1 }, result: [42, 42, 1, 1], call_threshold: 2)
      class A
        FOO = 42
        class << self
          def foo
            _foo = nil
            FOO
          end
        end
      end

      result = []

      result << A.foo
      result << A.foo

      class << A
        FOO = 1
      end

      result << A.foo
      result << A.foo

      result
    RUBY
  end

  def test_string_interpolation
    assert_compiles(<<~'RUBY', insns: %i[objtostring anytostring concatstrings], result: "foobar", call_threshold: 2)
      def make_str(foo, bar)
        "#{foo}#{bar}"
      end

      make_str("foo", "bar")
      make_str("foo", "bar")
    RUBY
  end

  def test_string_interpolation_cast
    assert_compiles(<<~'RUBY', insns: %i[objtostring anytostring concatstrings], result: "123")
      def make_str(foo, bar)
        "#{foo}#{bar}"
      end

      make_str(1, 23)
    RUBY
  end

  def test_checkkeyword
    assert_compiles(<<~'RUBY', insns: %i[checkkeyword], result: [2, 5])
      def foo(foo: 1+1)
        foo
      end

      [foo, foo(foo: 5)]
    RUBY
  end

  def test_struct_aref
    assert_compiles(<<~RUBY)
      def foo(obj)
        obj.foo
        obj.bar
      end

      Foo = Struct.new(:foo, :bar)
      foo(Foo.new(123))
      foo(Foo.new(123))
    RUBY
  end

  def test_struct_aset
    assert_compiles(<<~RUBY)
      def foo(obj)
        obj.foo = 123
        obj.bar = 123
      end

      Foo = Struct.new(:foo, :bar)
      foo(Foo.new(123))
      foo(Foo.new(123))
    RUBY
  end

  def test_getblockparam
    assert_compiles(<<~'RUBY', insns: [:getblockparam])
      def foo &blk
        2.times do
          blk
        end
      end

      foo {}
      foo {}
    RUBY
  end

  def test_getblockparamproxy
    # Currently two side exits as OPTIMIZED_METHOD_TYPE_CALL is unimplemented
    assert_compiles(<<~'RUBY', insns: [:getblockparamproxy], exits: { opt_send_without_block: 2 })
      def foo &blk
        p blk.call
        p blk.call
      end

      foo { 1 }
      foo { 2 }
    RUBY
  end

  def test_getblockparamproxy_with_no_block
    # Currently side exits on the send
    assert_compiles(<<~'RUBY', insns: [:getblockparamproxy], exits: { send: 2 })
      def bar
      end

      def foo &blk
        bar(&blk)
        bar(&blk)
      end

      foo
      foo
    RUBY
  end

  def test_send_splat
    assert_compiles(<<~'RUBY', result: "3#1,2,3/P", exits: {})
      def internal_method(*args)
        "#{args.size}##{args.join(",")}"
      end

      def jit_method
        send(:internal_method, *[1, 2, 3]) + "/P"
      end

      jit_method
    RUBY
  end

  def test_send_multiarg
    assert_compiles(<<~'RUBY', result: "3#1,2,3/Q")
      def internal_method(*args)
        "#{args.size}##{args.join(",")}"
      end

      def jit_method
        send(:internal_method, 1, 2, 3) + "/Q"
      end

      jit_method
    RUBY
  end

  def test_send_kwargs
    # For now, this side-exits when calls include keyword args
    assert_compiles(<<~'RUBY', result: "2#a:1,b:2/A", exits: {opt_send_without_block: 1})
      def internal_method(**kw)
        "#{kw.size}##{kw.keys.map { |k| "#{k}:#{kw[k]}" }.join(",")}"
      end

      def jit_method
        send(:internal_method, a: 1, b: 2) + "/A"
      end
      jit_method
    RUBY
  end

  def test_send_kwargs_in_receiver_only
    assert_compiles(<<~'RUBY', result: "0/RK", exits: {})
      def internal_method(**kw)
        "#{kw.size}"
      end

      def jit_method
        send(:internal_method) + "/RK"
      end
      jit_method
    RUBY
  end

  def test_send_with_underscores
    assert_compiles(<<~'RUBY', result: "0/RK", exits: {})
      def internal_method(**kw)
        "#{kw.size}"
      end

      def jit_method
        __send__(:internal_method) + "/RK"
      end
      jit_method
    RUBY
  end

  def test_send_kwargs_splat
    # For now, this side-exits when calling with a splat
    assert_compiles(<<~'RUBY', result: "2#a:1,b:2/B", exits: {opt_send_without_block: 1})
      def internal_method(**kw)
        "#{kw.size}##{kw.keys.map { |k| "#{k}:#{kw[k]}" }.join(",")}"
      end

      def jit_method
        send(:internal_method, **{ a: 1, b: 2 }) + "/B"
      end
      jit_method
    RUBY
  end

  def test_send_block
    # Setlocal_wc_0 sometimes side-exits on write barrier
    assert_compiles(<<~'RUBY', result: "b:n/b:y/b:y/b:n", exits: { :setlocal_WC_0 => 0..1 })
      def internal_method(&b)
        "b:#{block_given? ? "y" : "n"}"
      end

      def jit_method
        b7 = proc { 7 }
        [
          send(:internal_method),
          send(:internal_method, &b7),
          send(:internal_method) { 7 },
          send(:internal_method, &nil),
        ].join("/")
      end
      jit_method
    RUBY
  end

  def test_send_block_calling
    assert_compiles(<<~'RUBY', result: "1a2", exits: {})
      def internal_method
        out = yield
        "1" + out + "2"
      end

      def jit_method
        __send__(:internal_method) { "a" }
      end
      jit_method
    RUBY
  end

  def test_send_block_only_receiver
    assert_compiles(<<~'RUBY', result: "b:n", exits: {})
      def internal_method(&b)
        "b:#{block_given? ? "y" : "n"}"
      end

      def jit_method
        send(:internal_method)
      end
      jit_method
    RUBY
  end

  def test_send_block_only_sender
    assert_compiles(<<~'RUBY', result: "Y/Y/Y/Y", exits: {})
      def internal_method
        "Y"
      end

      def jit_method
        b7 = proc { 7 }
        [
          send(:internal_method),
          send(:internal_method, &b7),
          send(:internal_method) { 7 },
          send(:internal_method, &nil),
        ].join("/")
      end
      jit_method
    RUBY
  end

  def test_multisend
    assert_compiles(<<~'RUBY', result: "77")
      def internal_method
        "7"
      end

      def jit_method
        send(:send, :internal_method) + send(:send, :send, :internal_method)
      end
      jit_method
    RUBY
  end

  def test_getivar_opt_plus
    assert_no_exits(<<~RUBY)
      class TheClass
        def initialize
            @levar = 1
        end

        def get_sum
            sum = 0
            # The type of levar is unknown,
            # but this still should not exit
            sum += @levar
            sum
        end
      end

      obj = TheClass.new
      obj.get_sum
    RUBY
  end

  def test_super_iseq
    assert_compiles(<<~'RUBY', insns: %i[invokesuper opt_plus opt_mult], result: 15)
      class A
        def foo
          1 + 2
        end
      end

      class B < A
        def foo
          super * 5
        end
      end

      B.new.foo
    RUBY
  end

  def test_super_cfunc
    assert_compiles(<<~'RUBY', insns: %i[invokesuper], result: "Hello")
      class Gnirts < String
        def initialize
          super(-"olleH")
        end

        def to_s
          super().reverse
        end
      end

      Gnirts.new.to_s
    RUBY
  end

  # Tests calling a variadic cfunc with many args
  def test_build_large_struct
    assert_compiles(<<~RUBY, insns: %i[opt_send_without_block], call_threshold: 2)
      ::Foo = Struct.new(:a, :b, :c, :d, :e, :f, :g, :h)

      def build_foo
        ::Foo.new(:a, :b, :c, :d, :e, :f, :g, :h)
      end

      build_foo
      build_foo
    RUBY
  end

  def test_fib_recursion
    assert_compiles(<<~'RUBY', insns: %i[opt_le opt_minus opt_plus opt_send_without_block], result: 34)
      def fib(n)
        return n if n <= 1
        fib(n-1) + fib(n-2)
      end

      fib(9)
    RUBY
  end

  def test_optarg_and_kwarg
    assert_no_exits(<<~'RUBY')
      def opt_and_kwarg(a, b=nil, c: nil)
      end

      2.times do
        opt_and_kwarg(1, 2, c: 3)
      end
    RUBY
  end

  def test_cfunc_kwarg
    assert_no_exits('{}.store(:value, foo: 123)')
    assert_no_exits('{}.store(:value, foo: 123, bar: 456, baz: 789)')
    assert_no_exits('{}.merge(foo: 123)')
    assert_no_exits('{}.merge(foo: 123, bar: 456, baz: 789)')
  end

  # regression test simplified from URI::Generic#hostname=
  def test_ctx_different_mappings
    assert_compiles(<<~'RUBY', frozen_string_literal: true)
      def foo(v)
        !(v&.start_with?('[')) && v&.index(':')
      end

      foo(nil)
      foo("example.com")
    RUBY
  end

  def test_no_excessive_opt_getinlinecache_invalidation
    assert_compiles(<<~'RUBY', exits: :any, result: :ok)
      objects = [Object.new, Object.new]

      objects.each do |o|
        class << o
          def foo
            Object
          end
        end
      end

      9000.times {
        objects[0].foo
        objects[1].foo
      }

      stats = RubyVM::YJIT.runtime_stats
      return :ok unless stats[:all_stats]
      return :ok if stats[:invalidation_count] < 10

      :fail
    RUBY
  end

  def assert_no_exits(script)
    assert_compiles(script)
  end

  ANY = Object.new
  def assert_compiles(test_script, insns: [], call_threshold: 1, stdout: nil, exits: {}, result: ANY, frozen_string_literal: nil)
    reset_stats = <<~RUBY
      RubyVM::YJIT.runtime_stats
      RubyVM::YJIT.reset_stats!
    RUBY

    write_results = <<~RUBY
      stats = RubyVM::YJIT.runtime_stats

      def collect_insns(iseq)
        insns = RubyVM::YJIT.insns_compiled(iseq)
        iseq.each_child { |c| insns.concat collect_insns(c) }
        insns
      end

      iseq = RubyVM::InstructionSequence.of(_test_proc)
      IO.open(3).write Marshal.dump({
        result: #{result == ANY ? "nil" : "result"},
        stats: stats,
        insns: collect_insns(iseq),
        disasm: iseq.disasm
      })
    RUBY

    script = <<~RUBY
      #{"# frozen_string_literal: true" if frozen_string_literal}
      _test_proc = -> {
        #{test_script}
      }
      #{reset_stats}
      result = _test_proc.call
      #{write_results}
    RUBY

    status, out, err, stats = eval_with_jit(script, call_threshold: call_threshold)

    assert status.success?, "exited with status #{status.to_i}, stderr:\n#{err}"

    assert_equal stdout.chomp, out.chomp if stdout

    unless ANY.equal?(result)
      assert_equal result, stats[:result]
    end

    runtime_stats = stats[:stats]
    insns_compiled = stats[:insns]
    disasm = stats[:disasm]

    # Check that exit counts are as expected
    # Full stats are only available when --enable-yjit=dev
    if runtime_stats[:all_stats]
      recorded_exits = runtime_stats.select { |k, v| k.to_s.start_with?("exit_") }
      recorded_exits = recorded_exits.reject { |k, v| v == 0 }

      recorded_exits.transform_keys! { |k| k.to_s.gsub("exit_", "").to_sym }
      # Exits can be specified as a hash of stat-name symbol to integer for exact exits.
      # or stat-name symbol to range if the number of side exits might vary (e.g. write
      # barriers, cache misses.)
      if exits != :any &&
        exits != recorded_exits &&
        !exits.all? { |k, v| v === recorded_exits[k] } # triple-equal checks range membership or integer equality
        flunk "Expected #{exits.empty? ? "no" : exits.inspect} exits" \
          ", but got\n#{recorded_exits.inspect}"
      end
    end

    # Only available when --enable-yjit=dev
    if runtime_stats[:all_stats]
      missed_insns = insns.dup

      insns_compiled.each do |op|
        if missed_insns.include?(op)
          # This instruction was compiled
          missed_insns.delete(op)
        end
      end

      unless missed_insns.empty?
        flunk "Expected to compile instructions #{missed_insns.join(", ")} but didn't.\niseq:\n#{disasm}"
      end
    end
  end

  def script_shell_encode(s)
    # We can't pass utf-8-encoded characters directly in a shell arg. But we can use Ruby \u constants.
    s.chars.map { |c| c.ascii_only? ? c : "\\u%x" % c.codepoints[0] }.join
  end

  def eval_with_jit(script, call_threshold: 1, timeout: 1000)
    args = [
      "--disable-gems",
      "--yjit-call-threshold=#{call_threshold}",
      "--yjit-stats"
    ]
    args << "-e" << script_shell_encode(script)
    stats_r, stats_w = IO.pipe
    out, err, status = EnvUtil.invoke_ruby(args,
      '', true, true, timeout: timeout, ios: {3 => stats_w}
    )
    stats_w.close
    stats = stats_r.read
    stats = Marshal.load(stats) if !stats.empty?
    stats_r.close
    [status, out, err, stats]
  end
end