C# ILGenerator.CompareEqual方法代码示例

        /// <summary>
        /// Generates CIL for the expression.
        /// </summary>
        /// <param name="generator"> The generator to output the CIL to. </param>
        /// <param name="optimizationInfo"> Information about any optimizations that should be performed. </param>
        public override void GenerateCode(ILGenerator generator, OptimizationInfo optimizationInfo)
        {
            // Special-case the delete operator.
            if (this.OperatorType == OperatorType.Delete)
            {
                GenerateDelete(generator, optimizationInfo);
                return;
            }

            // If a return value is not expected, generate only the side-effects.
            /*if (optimizationInfo.SuppressReturnValue == true)
            {
                this.GenerateSideEffects(generator, optimizationInfo);
                return;
            }*/

            // Special-case the typeof operator.
            if (this.OperatorType == OperatorType.Typeof)
            {
                GenerateTypeof(generator, optimizationInfo);
                return;
            }

            // Load the operand onto the stack.
            this.Operand.GenerateCode(generator, optimizationInfo);

            // Convert the operand to the correct type.
            switch (this.OperatorType)
            {
                case OperatorType.Plus:
                case OperatorType.Minus:
                    EmitConversion.ToNumber(generator, this.Operand.ResultType);
                    break;

                case OperatorType.BitwiseNot:
                    EmitConversion.ToInt32(generator, this.Operand.ResultType);
                    break;

                case OperatorType.LogicalNot:
                    EmitConversion.ToBool(generator, this.Operand.ResultType);
                    break;
            }

            // Apply the operator.
            switch (this.OperatorType)
            {
                case OperatorType.Plus:
                    break;

                case OperatorType.Minus:
                    generator.Negate();
                    break;

                case OperatorType.BitwiseNot:
                    generator.BitwiseNot();
                    break;

                case OperatorType.LogicalNot:
                    generator.LoadBoolean(false);
                    generator.CompareEqual();
                    break;

                case OperatorType.Void:
                    generator.Pop();
                    EmitHelpers.EmitUndefined(generator);
                    break;

                default:
                    throw new NotImplementedException(string.Format("Unsupported operator {0}", this.OperatorType));
            }
        }

        /// <summary>
        /// Generates IL for the script.
        /// </summary>
        /// <param name="generator"> The generator to output the CIL to. </param>
        /// <param name="optimizationInfo"> Information about any optimizations that should be performed. </param>
        protected override void GenerateCode(ILGenerator generator, OptimizationInfo optimizationInfo)
        {
            // Method signature: object FunctionDelegate(Compiler.Scope scope, object thisObject, Library.FunctionInstance functionObject, object[] arguments)

            // Initialize the scope (note: the initial scope for a function is always declarative).
            this.InitialScope.GenerateScopeCreation(generator, optimizationInfo);

            // Verify the scope is correct.
            VerifyScope(generator);

            // In ES3 the "this" value must be an object.  See 10.4.3 in the spec.
            if (this.StrictMode == false && this.MethodOptimizationHints.HasThis == true)
            {
                // if (thisObject == null || thisObject == Null.Value || thisObject == Undefined.Value)
                EmitHelpers.LoadThis(generator);
                generator.LoadNull();
                generator.CompareEqual();
                EmitHelpers.LoadThis(generator);
                EmitHelpers.EmitNull(generator);
                generator.CompareEqual();
                generator.BitwiseOr();
                EmitHelpers.LoadThis(generator);
                EmitHelpers.EmitUndefined(generator);
                generator.CompareEqual();
                generator.BitwiseOr();

                // {
                var startOfFalse = generator.CreateLabel();
                generator.BranchIfFalse(startOfFalse);

                // thisObject = engine.Global;
                EmitHelpers.LoadScriptEngine(generator);
                generator.Call(ReflectionHelpers.ScriptEngine_Global);

                // } else {
                var endOfIf = generator.CreateLabel();
                generator.Branch(endOfIf);
                generator.DefineLabelPosition(startOfFalse);

                // thisObject = TypeConverter.ToObject(thisObject);
                EmitHelpers.LoadThis(generator);
                EmitConversion.ToObject(generator, PrimitiveType.Any);

                // }
                generator.DefineLabelPosition(endOfIf);
                EmitHelpers.StoreThis(generator);
            }

            // Transfer the function name into the scope.
            if (string.IsNullOrEmpty(this.Name) == false &&
                this.ArgumentNames.Contains(this.Name) == false &&
                optimizationInfo.MethodOptimizationHints.HasVariable(this.Name))
            {
                EmitHelpers.LoadFunction(generator);
                var functionName = new NameExpression(this.InitialScope, this.Name);
                functionName.GenerateSet(generator, optimizationInfo, PrimitiveType.Any, false);
            }

            // Transfer the arguments object into the scope.
            if (this.MethodOptimizationHints.HasArguments == true && this.ArgumentNames.Contains("arguments") == false)
            {
                // prototype
                EmitHelpers.LoadScriptEngine(generator);
                generator.Call(ReflectionHelpers.ScriptEngine_Object);
                generator.Call(ReflectionHelpers.FunctionInstance_InstancePrototype);
                // callee
                EmitHelpers.LoadFunction(generator);
                generator.CastClass(typeof(Library.UserDefinedFunction));
                // scope
                EmitHelpers.LoadScope(generator);
                generator.CastClass(typeof(DeclarativeScope));
                // argumentValues
                EmitHelpers.LoadArgumentsArray(generator);
                generator.NewObject(ReflectionHelpers.Arguments_Constructor);
                var arguments = new NameExpression(this.InitialScope, "arguments");
                arguments.GenerateSet(generator, optimizationInfo, PrimitiveType.Any, false);
            }

            // Transfer the argument values into the scope.
            // Note: the arguments array can be smaller than expected.
            if (this.ArgumentNames.Count > 0)
            {
                var endOfArguments = generator.CreateLabel();
                for (int i = 0; i < this.ArgumentNames.Count; i++)
                {
                    // Check if a duplicate argument name exists.
                    bool duplicate = false;
                    for (int j = i + 1; j < this.ArgumentNames.Count; j++)
                        if (this.ArgumentNames[i] == this.ArgumentNames[j])
                        {
                            duplicate = true;
                            break;
                        }
                    if (duplicate == true)
                        continue;
//.........这里部分代码省略.........

        /// <summary>
        /// Generates CIL for the relational operators.
        /// </summary>
        /// <param name="generator"> The generator to output the CIL to. </param>
        /// <param name="optimizationInfo"> Information about any optimizations that should be performed. </param>
        private void GenerateRelational(ILGenerator generator, OptimizationInfo optimizationInfo)
        {
            // Get the statically-determined types of the left and right operands.
            PrimitiveType leftType = this.Left.ResultType;
            PrimitiveType rightType = this.Right.ResultType;

            // The relational operators compare strings if both of the operands are strings.
            if (leftType == PrimitiveType.String && rightType == PrimitiveType.String)
            {
                // Both of the operands are strings.

                // Load the left hand side operand onto the stack.
                this.Left.GenerateCode(generator, optimizationInfo);

                // Load the right hand side operand onto the stack.
                this.Right.GenerateCode(generator, optimizationInfo);

                // Compare the two strings.
                generator.Call(ReflectionHelpers.String_CompareOrdinal);
                switch (this.OperatorType)
                {
                    case OperatorType.LessThan:
                        generator.LoadInt32(0);
                        generator.CompareLessThan();
                        break;
                    case OperatorType.LessThanOrEqual:
                        generator.LoadInt32(1);
                        generator.CompareLessThan();
                        break;
                    case OperatorType.GreaterThan:
                        generator.LoadInt32(0);
                        generator.CompareGreaterThan();
                        break;
                    case OperatorType.GreaterThanOrEqual:
                        generator.LoadInt32(-1);
                        generator.CompareGreaterThan();
                        break;
                }
            }
            else if (leftType == PrimitiveType.Int32 && rightType == PrimitiveType.Int32)
            {
                // Both of the operands are integers.

                // Load the left hand side operand onto the stack.
                this.Left.GenerateCode(generator, optimizationInfo);

                // Load the right hand side operand onto the stack.
                this.Right.GenerateCode(generator, optimizationInfo);

                // Compare the two numbers.
                switch (this.OperatorType)
                {
                    case OperatorType.LessThan:
                        generator.CompareLessThan();
                        break;
                    case OperatorType.GreaterThan:
                        generator.CompareGreaterThan();
                        break;

                    case OperatorType.LessThanOrEqual:
                        // a <= b   <-->   (a > b) == false
                        generator.CompareGreaterThan();
                        generator.LoadBoolean(false);
                        generator.CompareEqual();
                        break;

                    case OperatorType.GreaterThanOrEqual:
                        // a >= b   <-->   (a < b) == false
                        generator.CompareLessThan();
                        generator.LoadBoolean(false);
                        generator.CompareEqual();
                        break;
                }
            }
            else if (PrimitiveTypeUtilities.IsNumeric(leftType) || PrimitiveTypeUtilities.IsNumeric(rightType))
            {
                // At least one of the operands is a number.

                // Load the left hand side operand onto the stack.
                this.Left.GenerateCode(generator, optimizationInfo);

                // Convert the operand to a number.
                EmitConversion.ToNumber(generator, leftType);

                // Load the right hand side operand onto the stack.
                this.Right.GenerateCode(generator, optimizationInfo);

                // Convert the operand to a number.
                EmitConversion.ToNumber(generator, rightType);

                // Compare the two numbers.
                switch (this.OperatorType)
                {
                    case OperatorType.LessThan:
                        generator.CompareLessThan();
//.........这里部分代码省略.........

//.........这里部分代码省略.........

            // Load the right hand side onto the stack.
            this.Right.GenerateCode(generator, optimizationInfo);

            // Convert the right argument.
            switch (this.OperatorType)
            {
                // Arithmetic operations.
                case OperatorType.Subtract:
                case OperatorType.Multiply:
                case OperatorType.Divide:
                case OperatorType.Modulo:
                    EmitConversion.ToNumber(generator, this.Right.ResultType);
                    break;

                // Bitwise operations.
                case OperatorType.BitwiseAnd:
                case OperatorType.BitwiseOr:
                case OperatorType.BitwiseXor:
                    EmitConversion.ToInt32(generator, this.Right.ResultType);
                    break;
                case OperatorType.LeftShift:
                case OperatorType.SignedRightShift:
                case OperatorType.UnsignedRightShift:
                    EmitConversion.ToUInt32(generator, this.Right.ResultType);
                    generator.LoadInt32(0x1F);
                    generator.BitwiseAnd();
                    break;

                // Equality operations.
                case OperatorType.Equal:
                case OperatorType.StrictlyEqual:
                case OperatorType.NotEqual:
                case OperatorType.StrictlyNotEqual:
                    EmitConversion.ToAny(generator, this.Right.ResultType);
                    break;
            }

            // Apply the operator.
            switch (this.OperatorType)
            {
                // Arithmetic operations.
                case OperatorType.Subtract:
                    generator.Subtract();
                    break;
                case OperatorType.Multiply:
                    generator.Multiply();
                    break;
                case OperatorType.Divide:
                    generator.Divide();
                    break;
                case OperatorType.Modulo:
                    generator.Remainder();
                    break;

                // Bitwise operations.
                case OperatorType.BitwiseAnd:
                    generator.BitwiseAnd();
                    break;
                case OperatorType.BitwiseOr:
                    generator.BitwiseOr();
                    break;
                case OperatorType.BitwiseXor:
                    generator.BitwiseXor();
                    break;

                // Shift operations.
                case OperatorType.LeftShift:
                    generator.ShiftLeft();
                    break;
                case OperatorType.SignedRightShift:
                    generator.ShiftRight();
                    break;
                case OperatorType.UnsignedRightShift:
                    generator.ShiftRightUnsigned();
                    EmitConversion.ToNumber(generator, PrimitiveType.UInt32);
                    break;

                // Equality operations.
                case OperatorType.Equal:
                    generator.Call(ReflectionHelpers.TypeComparer_Equals);
                    break;
                case OperatorType.StrictlyEqual:
                    generator.Call(ReflectionHelpers.TypeComparer_StrictEquals);
                    break;
                case OperatorType.NotEqual:
                    generator.Call(ReflectionHelpers.TypeComparer_Equals);
                    generator.LoadBoolean(false);
                    generator.CompareEqual();
                    break;
                case OperatorType.StrictlyNotEqual:
                    generator.Call(ReflectionHelpers.TypeComparer_StrictEquals);
                    generator.LoadBoolean(false);
                    generator.CompareEqual();
                    break;

                default:
                    throw new NotImplementedException(string.Format("Unsupported operator {0}", this.OperatorType));
            }
        }

        /// <summary>
        /// Pops the value on the stack, converts it from one type to another, then pushes the
        /// result onto the stack.  Undefined is converted to the given default value.
        /// </summary>
        /// <param name="generator"> The IL generator. </param>
        /// <param name="fromType"> The type to convert from. </param>
        /// <param name="targetParameter"> The type to convert to and the default value, if there is one. </param>
        private static void EmitTypeConversion(ILGenerator generator, Type fromType, BinderArgument argument)
        {
            // Emit either the default value if there is one, otherwise emit "undefined".
            if (argument.HasDefaultValue)
            {
                // Check if the input value is undefined.
                var elseClause = generator.CreateLabel();
                generator.Duplicate();
                generator.BranchIfNull(elseClause);
                generator.Duplicate();
                generator.LoadField(ReflectionHelpers.Undefined_Value);
                generator.CompareEqual();
                generator.BranchIfTrue(elseClause);

                // Convert as per normal.
                EmitTypeConversion(generator, fromType, argument.Type);

                // Jump to the end.
                var endOfIf = generator.CreateLabel();
                generator.Branch(endOfIf);
                generator.DefineLabelPosition(elseClause);

                // Pop the existing value and emit the default value.
                generator.Pop();
                EmitUndefined(generator, argument);

                // Define the end of the block.
                generator.DefineLabelPosition(endOfIf);
            }
            else
            {
                // Convert as per normal.
                EmitTypeConversion(generator, fromType, argument.Type);
            }
        }

        /// <summary>
        /// Pops the value on the stack, converts it to an integer, then pushes the integer result
        /// onto the stack.
        /// </summary>
        /// <param name="generator"> The IL generator. </param>
        /// <param name="fromType"> The type to convert from. </param>
        public static void ToInteger(ILGenerator generator, PrimitiveType fromType)
        {
            // Check that a conversion is actually necessary.
            if (fromType == PrimitiveType.Int32 || fromType == PrimitiveType.UInt32 || fromType == PrimitiveType.Bool)
                return;

            switch (fromType)
            {
                case PrimitiveType.Undefined:
                case PrimitiveType.Null:
                    // Converting from undefined or null produces 0.
                    generator.Pop();
                    generator.LoadInt32(0);
                    break;

                case PrimitiveType.Number:
                    // Converting from a number produces the following:
                    // Any number between -2147483648 and +2147483647 -> itself
                    // Any number smaller than -2147483648 -> -2147483648
                    // Any number larger than +2147483647 -> +2147483647
                    // NaN -> 0

                    // bool isPositiveInfinity = input > 2147483647.0
                    var isPositiveInfinity = generator.CreateTemporaryVariable(typeof(bool));
                    generator.Duplicate();
                    generator.LoadDouble(2147483647.0);
                    generator.CompareGreaterThan();
                    generator.StoreVariable(isPositiveInfinity);

                    // bool notNaN = input == input
                    var notNaN = generator.CreateTemporaryVariable(typeof(bool));
                    generator.Duplicate();
                    generator.Duplicate();
                    generator.CompareEqual();
                    generator.StoreVariable(notNaN);

                    // input = (int)input
                    // Infinity -> -2147483648
                    // -Infinity -> -2147483648
                    // NaN -> -2147483648
                    generator.ConvertToInteger();

                    // input = input & -((int)notNaN)
                    generator.LoadVariable(notNaN);
                    generator.Negate();
                    generator.BitwiseAnd();

                    // input = input - (int)isPositiveInfinity
                    generator.LoadVariable(isPositiveInfinity);
                    generator.Subtract();

                    // The temporary variables are no longer needed.
                    generator.ReleaseTemporaryVariable(notNaN);
                    generator.ReleaseTemporaryVariable(isPositiveInfinity);
                    break;

                case PrimitiveType.String:
                case PrimitiveType.ConcatenatedString:
                case PrimitiveType.Any:
                case PrimitiveType.Object:
                    // Otherwise, fall back to calling TypeConverter.ToInteger()
                    generator.Call(ReflectionHelpers.TypeConverter_ToInteger);
                    break;

                default:
                    throw new NotImplementedException(string.Format("Unsupported primitive type: {0}", fromType));
            }
        }

        /// <summary>
        /// Pops the value on the stack, converts it to a boolean, then pushes the boolean result
        /// onto the stack.
        /// </summary>
        /// <param name="generator"> The IL generator. </param>
        /// <param name="fromType"> The type to convert from. </param>
        public static void ToBool(ILGenerator generator, PrimitiveType fromType)
        {
            // Check that a conversion is actually necessary.
            if (fromType == PrimitiveType.Bool)
                return;

            switch (fromType)
            {
                case PrimitiveType.Undefined:
                case PrimitiveType.Null:
                    // Converting from undefined or null produces false.
                    generator.Pop();
                    generator.LoadInt32(0);
                    break;

                case PrimitiveType.Int32:
                case PrimitiveType.UInt32:
                    // Converting from an integer produces true if the integer is non-zero.
                    generator.LoadInt32(0);
                    generator.CompareGreaterThanUnsigned();
                    break;

                case PrimitiveType.Number:
                    // Converting from a number produces true if the number is non-zero and not NaN.
                    var temp = generator.CreateTemporaryVariable(fromType);
                    generator.StoreVariable(temp);

                    // input != 0
                    generator.LoadVariable(temp);
                    generator.LoadDouble(0.0);
                    generator.CompareEqual();
                    generator.LoadInt32(0);
                    generator.CompareEqual();

                    // input == input
                    generator.LoadVariable(temp);
                    generator.Duplicate();
                    generator.CompareEqual();

                    // &&
                    generator.CompareEqual();

                    // The temporary variable is no longer needed.
                    generator.ReleaseTemporaryVariable(temp);
                    break;

                case PrimitiveType.String:
                    // Converting from a string produces true if the string is not empty.
                    generator.Call(ReflectionHelpers.String_Length);
                    generator.LoadInt32(0);
                    generator.CompareGreaterThan();
                    break;

                case PrimitiveType.ConcatenatedString:
                    // Converting from a string produces true if the string is not empty.
                    generator.Call(ReflectionHelpers.ConcatenatedString_Length);
                    generator.LoadInt32(0);
                    generator.CompareGreaterThan();
                    break;

                case PrimitiveType.Any:
                case PrimitiveType.Object:
                    // Otherwise, fall back to calling TypeConverter.ToBoolean()
                    generator.Call(ReflectionHelpers.TypeConverter_ToBoolean);
                    break;

                default:
                    throw new NotImplementedException(string.Format("Unsupported primitive type: {0}", fromType));
            }
        }