C# Context.SetResult方法代码示例

        /// <summary>
        /// Performs stage specific processing on the compiler context.
        /// </summary>
        void IMethodCompilerStage.Run()
        {
            if (AreExceptions)
                return;

            foreach (var block in this.basicBlocks)
            {
                if (block.Label == Int32.MaxValue)
                    continue;

                for (var context = new Context(this.instructionSet, block); !context.EndOfInstruction; context.GotoNext())
                {
                    if (context.Instruction is PhiInstruction)
                        this.ProcessPhiInstruction(block, context);

                    for (var i = 0; i < context.OperandCount; ++i)
                    {
                        var op = context.GetOperand(i);
                        if (op is SsaOperand)
                            context.SetOperand(i, (op as SsaOperand).Operand);
                    }

                    for (var i = 0; i < context.ResultCount; ++i)
                    {
                        var op = context.GetResult(i);
                        if (op is SsaOperand)
                            context.SetResult(i, (op as SsaOperand).Operand);
                    }
                }
            }
        }

        private static void PatchInvoke(BaseMethodCompiler methodCompiler)
        {
            // check if instance is null (if so, it's a static call to the methodPointer)

            MosaField methodPointerField = GetField(methodCompiler.Method.DeclaringType, "methodPointer");
            int methodPointerOffset = methodCompiler.TypeLayout.GetFieldOffset(methodPointerField);
            Operand methodPointerOffsetOperand = Operand.CreateConstant(methodCompiler.TypeSystem, methodPointerOffset);

            MosaField instanceField = GetField(methodCompiler.Method.DeclaringType, "instance");
            int instanceOffset = methodCompiler.TypeLayout.GetFieldOffset(instanceField);
            Operand instanceOffsetOperand = Operand.CreateConstant(methodCompiler.TypeSystem, instanceOffset);

            var size = methodCompiler.Architecture.NativeInstructionSize;
            bool withReturn = (methodCompiler.Method.Signature.ReturnType == null) ? false : !methodCompiler.Method.Signature.ReturnType.IsVoid;

            Context b0 = new Context(CreateMethodStructure(methodCompiler, false));
            Context b1 = new Context(methodCompiler.BasicBlocks.CreateBlock());
            Context b2 = new Context(methodCompiler.BasicBlocks.CreateBlock());
            Context b3 = new Context(methodCompiler.BasicBlocks.CreateBlock());

            Operand[] vrs = new Operand[methodCompiler.Parameters.Length];

            for (int i = 0; i < methodCompiler.Parameters.Length; i++)
            {
                vrs[i] = methodCompiler.VirtualRegisters.Allocate(methodCompiler.Parameters[i].Type);

                //fixme: handle structs
                var loadInstruction = BaseMethodCompilerStage.GetLoadInstruction(vrs[i].Type);
                var moveSize = BaseMethodCompilerStage.GetInstructionSize(vrs[i].Type);

                b0.AppendInstruction(loadInstruction, moveSize, vrs[i], methodCompiler.StackFrame, methodCompiler.Parameters[i]);
            }

            Operand thisOperand = vrs[0];

            Operand opMethod = methodCompiler.VirtualRegisters.Allocate(methodCompiler.TypeSystem.BuiltIn.U4);
            Operand opInstance = methodCompiler.VirtualRegisters.Allocate(thisOperand.Type);
            Operand opCompare = methodCompiler.VirtualRegisters.Allocate(methodCompiler.TypeSystem.BuiltIn.I4);

            Operand opReturn = withReturn ? methodCompiler.AllocateVirtualRegisterOrStackSlot(methodCompiler.Method.Signature.ReturnType) : null;
            Operand c0 = Operand.CreateConstant(methodCompiler.TypeSystem, 0);

            b0.AppendInstruction(IRInstruction.LoadInteger, size, opMethod, thisOperand, methodPointerOffsetOperand);
            b0.AppendInstruction(IRInstruction.LoadInteger, size, opInstance, thisOperand, instanceOffsetOperand);
            b0.AppendInstruction(IRInstruction.CompareInteger, ConditionCode.Equal, opCompare, opInstance, c0);
            b0.AppendInstruction(IRInstruction.CompareIntegerBranch, ConditionCode.Equal, null, opCompare, c0);
            b0.AddBranchTarget(b2.Block);
            b0.AppendInstruction(IRInstruction.Jmp, b1.Block);

            // no instance
            b1.AppendInstruction(IRInstruction.Call, opReturn, opMethod);
            b1.InvokeMethod = methodCompiler.Method;
            for (int i = 1; i < methodCompiler.Parameters.Length; i++)
                b1.AddOperand(vrs[i]);
            if (withReturn)
                b1.SetResult(0, opReturn);
            b1.AppendInstruction(IRInstruction.Jmp, b3.Block);

            // instance
            b2.AppendInstruction(IRInstruction.Call, opReturn, opMethod);
            b2.InvokeMethod = methodCompiler.Method;
            b2.AddOperand(opInstance);
            for (int i = 1; i < methodCompiler.Parameters.Length; i++)
                b2.AddOperand(vrs[i]);
            if (withReturn)
                b2.SetResult(0, opReturn);
            b2.AppendInstruction(IRInstruction.Jmp, b3.Block);

            // return
            b3.AppendInstruction(IRInstruction.Return, methodCompiler.BasicBlocks.EpilogueBlock);
            if (withReturn)
                b3.SetOperand(0, opReturn);
        }

        /// <summary>
        /// Replaces the operand.
        /// </summary>
        /// <param name="lr">The lr.</param>
        /// <param name="replacement">The replacement.</param>
        private void ReplaceOperand(LiveRange lr, RegisterOperand replacement)
        {
            int opIdx;

            // Iterate all definition sites first
            foreach (int index in lr.Op.Definitions.ToArray())
            {
                Context def = new Context(instructionSet, index);
                if (def.Offset == lr.Start)
                {
                    opIdx = 0;
                    foreach (Operand r in def.Results)
                    {
                        // Is this the operand?
                        if (object.ReferenceEquals(r, lr.Op))
                            def.SetResult(opIdx, replacement);

                        opIdx++;
                    }

                    break;
                }
            }

            // Iterate all use sites
            foreach (int index in lr.Op.Uses.ToArray())
            {
                Context instr = new Context(instructionSet, index);

                if (instr.Offset <= lr.Start)
                {
                    // A use on instr.Offset == lr.Start is one from a previous definition!!
                }
                else if (instr.Offset <= lr.End)
                {
                    opIdx = 0;
                    foreach (Operand r in instr.Operands)
                    {
                        // Is this the operand?
                        if (object.ReferenceEquals(r, lr.Op))
                            instr.SetOperand(opIdx, replacement);

                        opIdx++;
                    }
                }
                else
                {
                    break;
                }
            }
        }

        /// <summary>
        /// 
        /// </summary>
        /// <param name="block"></param>
        private void RenameVariables(BasicBlock block)
        {
            for (var context = new Context(this.instructionSet, block); !context.EndOfInstruction; context.GotoNext())
            {
                if (!(context.Instruction is PhiInstruction))
                {
                    for (var i = 0; i < context.OperandCount; ++i)
                    {
                        var op = context.GetOperand(i);
                        if (!(op is StackOperand))
                            continue;
                        var name = NameForOperand(context.GetOperand(i));
                        if (!this.variableInformation.ContainsKey(name))
                            throw new Exception(name + " is not in dictionary [block = " + block + "]");
                        var index = this.variableInformation[name].Stack.Peek();
                        context.SetOperand(i, new SsaOperand(context.GetOperand(i), index));
                    }
                }

                if (PhiPlacementStage.IsAssignmentToStackVariable(context))
                {
                    var name = NameForOperand(context.Result);
                    var index = this.variableInformation[name].Count;
                    context.SetResult(new SsaOperand(context.Result, index));
                    this.variableInformation[name].Stack.Push(index);
                    ++this.variableInformation[name].Count;
                }
            }

            foreach (var s in block.NextBlocks)
            {
                var j = this.WhichPredecessor(s, block);
                for (var context = new Context(this.instructionSet, s); !context.EndOfInstruction; context.GotoNext())
                {
                    if (!(context.Instruction is PhiInstruction))
                        continue;
                    var name = NameForOperand(context.GetOperand(j));
                    if (this.variableInformation[name].Stack.Count > 0)
                    {
                        var index = this.variableInformation[name].Stack.Peek();
                        context.SetOperand(j, new SsaOperand(context.GetOperand(j), index));
                    }
                }
            }

            foreach (var s in this.dominanceCalculationStage.GetChildren(block))
            {
                this.RenameVariables(s);
            }

            for (var context = new Context(this.instructionSet, block); !context.EndOfInstruction; context.GotoNext())
            {
                if (PhiPlacementStage.IsAssignmentToStackVariable(context))
                {
                    var instName = context.Label + "." + context.Index;
                    var op = this.oldLefHandSide[instName];
                    var name = NameForOperand(op);
                    this.variableInformation[name].Stack.Pop();
                }
            }
        }