Cosmos/source/Indy.IL2CPU.IL.X86/Stelem_Any.cs
2007-11-16 12:50:03 +00:00

90 lines
No EOL
3 KiB
C#

using System;
using System.IO;
using Mono.Cecil;
using Mono.Cecil.Cil;
using CPU = Indy.IL2CPU.Assembler;
using CPUx86 = Indy.IL2CPU.Assembler.X86;
namespace Indy.IL2CPU.IL.X86 {
[OpCode(Code.Stelem_Any, true)]
public class Stelem_Any: Op {
private int mElementSize;
public Stelem_Any(Instruction aInstruction, MethodInformation aMethodInfo)
: base(aInstruction, aMethodInfo) {
TypeReference xType = aInstruction.Operand as TypeReference;
if (xType == null)
throw new Exception("Unable to determine Type!");
mElementSize = Engine.GetFieldStorageSize(xType);
if (mElementSize % 4 != 0) {
throw new Exception("ElementSize should be divisible by 4");
}
}
// todo: refactor other Stelem variants to use this method
public static void Assemble(CPU.Assembler aAssembler, int aElementSize) {
// stack - 3 == the array
// stack - 2 == the index
// stack - 1 == the new value
int xStackSize = aElementSize;
if(xStackSize % 4 != 0) {
xStackSize += 4 - xStackSize % 4;
}
aAssembler.Add(new CPU.Comment("; Index at: [esp + " + xStackSize + "]"));
aAssembler.Add(new CPU.Comment("; Array at: [esp + " + (xStackSize + 4) + "]"));
aAssembler.Add(new CPUx86.Move("ebx", "[esp + " + xStackSize + "]")); // the index
aAssembler.Add(new CPUx86.Move("ecx", "[esp + " + (xStackSize + 4) + "]")); // the array
aAssembler.Add(new CPUx86.Add("ecx", "12"));
Push(aAssembler, 4, "0x" + aElementSize.ToString("X"));
Push(aAssembler, 4, "ebx");
Multiply(aAssembler);
Push(aAssembler, 4, "ecx");
Add(aAssembler);
aAssembler.Add(new CPUx86.Pop("ecx"));
aAssembler.StackSizes.Pop();
for (int i = (aElementSize / 4) - 1; i >= 0; i -= 1) {
aAssembler.Add(new CPU.Comment("Start 1 dword"));
aAssembler.Add(new CPUx86.Pop("ebx"));
aAssembler.Add(new CPUx86.Move("[ecx]", "ebx"));
aAssembler.Add(new CPUx86.Add("ecx", "4"));
}
switch (aElementSize % 4) {
case 1: {
aAssembler.Add(new CPU.Comment("Start 1 byte"));
aAssembler.Add(new CPUx86.Pop("ebx"));
Move(aAssembler, "byte [ecx]", "bl");
break;
}
case 2: {
aAssembler.Add(new CPU.Comment("Start 1 word"));
aAssembler.Add(new CPUx86.Pop("ebx"));
Move(aAssembler, "word [ecx]", "bx");
break;
}
case 0: {
break;
}
default:
throw new Exception("Remainder size " + (aElementSize % 4) + " not supported!");
}
aAssembler.Add(new CPUx86.Add("esp", "0x8"));
//
// aAssembler.Add(new CPUx86.Move("[edx]", "ecx"));
//
// for (int i = 0; i < (aElementSize % 4); i++) {
// aAssembler.Add(new CPUx86.Pushd("eax"));
// if (i != 0) {
// aAssembler.Add(new CPUx86.Add("eax", "4"));
// aAssembler.Add(new CPUx86.Pushd("eax"));
// }
// }
aAssembler.StackSizes.Pop();
aAssembler.StackSizes.Pop();
aAssembler.StackSizes.Pop();
}
public override void DoAssemble() {
Assemble(Assembler, mElementSize);
}
}
}