void Dispatch(LuaThread thread, int frameBase, int resultCount, int fp, int ip)
{
try
{
while (true)
{
// Suspend coroutine (support for suspending at arbitrary instructions).
/*
* if ( thread.UnwoundFrames.Count > 0 )
* {
* thread.UnwoundFrames.Add( new Frame( frameBase, resultCount, fp, ip ) );
* return;
* }
*/
// Dispatch instructions.
Instruction i = prototype.Instructions[ip++];
switch (i.Opcode)
{
case Opcode.Move:
{
// R( A ) := R( B )
thread.Stack[fp + i.A] = thread.Stack[fp + i.B];
continue;
}
case Opcode.LoadK:
{
// R( A ) := K( Bx )
thread.Stack[fp + i.A] = K(i.Bx);
continue;
}
case Opcode.LoadBool:
{
// R( A ) := (bool)B
if (i.B != 0)
{
thread.Stack[fp + i.A] = true;
}
else
{
thread.Stack[fp + i.A] = false;
}
// if C skip next instruction
if (i.C != 0)
{
ip += 1;
}
continue;
}
case Opcode.LoadNil:
{
// R( A ) ... R( B ) := nil
for (int r = i.A; r <= i.B; ++r)
{
thread.Stack[fp + r] = null;
}
continue;
}
case Opcode.GetUpVal:
{
// R( A ) := U( B )
thread.Stack[fp + i.A] = upVals[i.B].Value;
continue;
}
case Opcode.GetGlobal:
{
// R( A ) := G[ K( Bx ) ]
thread.Stack[fp + i.A] = Environment.Index(K(i.Bx));
continue;
}
case Opcode.GetTable:
{
// R( A ) := R( B )[ RK( C ) ]
thread.Stack[fp + i.A] = thread.Stack[fp + i.B].Index(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.SetGlobal:
{
// G[ K( Bx ) ] := R( A )
Environment.NewIndex(K(i.Bx), thread.Stack[fp + i.A]);
continue;
}
case Opcode.SetUpVal:
{
// U( B ) := R( A )
upVals[i.B].Value = thread.Stack[fp + i.A];
continue;
}
case Opcode.SetTable:
{
// R( A )[ RK( B ) ] = RK( C )
thread.Stack[fp + i.A].NewIndex(RK(thread.Stack, fp, i.B), RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.NewTable:
{
// R( A ) := {} ( B is array size hint, C is hash size hint )
thread.Stack[fp + i.A] = new LuaTable(i.B, i.C);
continue;
}
case Opcode.Self:
{
LuaValue self = thread.Stack[fp + i.B];
// R( A + 1 ) := R( B )
thread.Stack[fp + i.A + 1] = self;
// R( A ) = R( B )[ RK( C ) ]
thread.Stack[fp + i.A] = self.Index(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Add:
{
// R( A ) := RK( B ) + RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).Add(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Sub:
{
// R( A ) := RK( B ) - RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).Subtract(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Mul:
{
// R( A ) := RK( B ) * RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).Multiply(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Div:
{
// R( A ) := RK( B ) / RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).Divide(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Mod:
{
// R( A ) := RK( B ) % RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).Modulus(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Pow:
{
// R( A ) := RK( B ) ^ RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).RaiseToPower(RK(thread.Stack, fp, i.C));
continue;
}
case Opcode.Unm:
{
// R( A ) := -R( B )
thread.Stack[fp + i.A] = thread.Stack[fp + i.B].UnaryMinus();
continue;
}
case Opcode.Not:
{
// R( A ) := not R( B )
LuaValue B = thread.Stack[fp + i.B];
thread.Stack[fp + i.A] = !(B != null && B.IsTrue());
continue;
}
case Opcode.Len:
{
// R( A ) := length of R( B )
thread.Stack[fp + i.A] = thread.Stack[fp + i.B].Length();
continue;
}
case Opcode.Concat:
{
// R( A ) := R( B ) .. ... .. R( C ), concatenating whole list
int listTop = fp + i.C;
int count = i.C - i.B + 1;
while (count > 1)
{
LuaValue left = thread.Stack[listTop - 1];
LuaValue right = thread.Stack[listTop - 0];
if (left.SupportsSimpleConcatenation() && right.SupportsSimpleConcatenation())
{
// Count how many we can concatenate in this pass.
int concatCount = 2;
for (concatCount = 2; concatCount < count; ++concatCount)
{
LuaValue operand = thread.Stack[listTop - concatCount];
if (!operand.SupportsSimpleConcatenation())
{
break;
}
}
// Concatenate them.
StringBuilder s = new StringBuilder();
for (int r = listTop - (concatCount - 1); r <= listTop; ++r)
{
s.Append(thread.Stack[r].ToString());
}
// Modify the thread.Stack top and continue.
thread.Stack[listTop - (concatCount - 1)] = s.ToString();
listTop -= concatCount - 1;
count -= concatCount - 1;
}
else
{
// Perform meta concatenation.
thread.Stack[listTop - 1] = left.Concatenate(right);
listTop -= 1;
count -= 1;
}
}
thread.Stack[fp + i.A] = thread.Stack[listTop];
continue;
}
case Opcode.Jmp:
{
// relative jump sBx ( relative to next instruction )
ip += i.sBx;
continue;
}
case Opcode.Eq:
{
// if ( RK( B ) == RK( C ) ) ~= A then skip associated jump
LuaValue B = RK(thread.Stack, fp, i.B);
LuaValue C = RK(thread.Stack, fp, i.C);
bool equals = B != null?B.Equals(C) : C == null;
if (equals == (i.A != 0))
{
i = prototype.Instructions[ip++];
ip += i.sBx;
}
else
{
ip += 1;
}
continue;
}
case Opcode.Lt:
{
// if ( RK( B ) < RK( C ) ) ~= A then skip associated jump
if (RK(thread.Stack, fp, i.B).LessThan(RK(thread.Stack, fp, i.C)) == (i.A != 0))
{
i = prototype.Instructions[ip++];
ip += i.sBx;
}
else
{
ip += 1;
}
continue;
}
case Opcode.Le:
{
// if ( RK( B ) <= RK( C ) ) ~= A then skip associated jump
if (RK(thread.Stack, fp, i.B).LessThanOrEquals(RK(thread.Stack, fp, i.C)) == (i.A != 0))
{
i = prototype.Instructions[ip++];
ip += i.sBx;
}
else
{
ip += 1;
}
continue;
}
case Opcode.Test:
{
// if not ( R( A ) <=> C ) then skip associated jump
LuaValue A = thread.Stack[fp + i.A];
if ((A != null && A.IsTrue()) == (i.C != 0))
{
i = prototype.Instructions[ip++];
ip += i.sBx;
}
else
{
ip += 1;
}
continue;
}
case Opcode.TestSet:
{
// if ( R( B ) <=> C ) then R( A ) := R( B ) else skip associated jump
LuaValue B = thread.Stack[fp + i.B];
if ((B != null && B.IsTrue()) == (i.C != 0))
{
// Set.
thread.Stack[fp + i.A] = thread.Stack[fp + i.B];
// Perform associated jump.
i = prototype.Instructions[ip++];
ip += i.sBx;
}
else
{
ip += 1;
}
continue;
}
case Opcode.Call:
{
// R( A ), ... , R( A + C - 2 ) := R( A )( R( A + 1 ), ... , R( A + B - 1 ) )
// Count arguments.
int callArgumentCount;
if (i.B != 0)
{
callArgumentCount = i.B - 1;
}
else
{
callArgumentCount = thread.Top - fp - i.A;
thread.Top = -1;
}
LuaValue function = thread.Stack[fp + i.A];
function.Call(thread, fp + i.A, callArgumentCount, i.C - 1);
if (thread.UnwoundFrames.Count > 0)
{
thread.UnwoundFrames.Add(new Frame(frameBase, resultCount, fp, ip));
return;
}
if (i.C != 0)
{
thread.StackWatermark(fp + prototype.StackSize);
}
else
{
thread.StackWatermark(Math.Max(fp + prototype.StackSize, thread.Top + 1));
}
continue;
}
case Opcode.TailCall:
{
// return R( A )( R( A + 1 ), ... , R( A + B - 1 ) )
thread.CloseUpVals(fp);
thread.StackLevels.RemoveAt(thread.StackLevels.Count - 1);
int callArgumentCount;
if (i.B != 0)
{
callArgumentCount = i.B - 1;
}
else
{
callArgumentCount = thread.Top - fp - i.A;
thread.Top = -1;
}
LuaValue function = thread.Stack[fp + i.A];
thread.Stack[frameBase] = function;
for (int argument = 0; argument < callArgumentCount; ++argument)
{
thread.Stack[frameBase + 1 + argument] = thread.Stack[fp + i.A + 1 + argument];
}
function.Call(thread, frameBase, callArgumentCount, resultCount);
return;
}
case Opcode.Return:
{
// return R( A ), ... R( A + B - 2 )
thread.CloseUpVals(fp);
thread.StackLevels.RemoveAt(thread.StackLevels.Count - 1);
// Find number of results we have.
int returnResultCount;
if (i.B != 0)
{
returnResultCount = i.B - 1;
}
else
{
returnResultCount = thread.Top + 1 - fp - i.A;
thread.Top = -1;
}
// Calculate number of results we want.
int copyCount;
if (resultCount != -1)
{
copyCount = Math.Min(resultCount, returnResultCount);
}
else
{
copyCount = returnResultCount;
thread.Top = frameBase + returnResultCount - 1;
}
// Copy results.
for (int result = 0; result < copyCount; ++result)
{
thread.Stack[frameBase + result] = thread.Stack[fp + i.A + result];
}
for (int result = copyCount; result < resultCount; ++result)
{
thread.Stack[frameBase + result] = null;
}
return;
}
/* A + 0 Index
* A + 1 Limit
* A + 2 Step
* A + 3 Var
*/
case Opcode.ForLoop:
{
LuaValue index = thread.Stack[fp + i.A + 0];
LuaValue limit = thread.Stack[fp + i.A + 1];
LuaValue step = thread.Stack[fp + i.A + 2];
// Index += Step
index = index.Add(step);
thread.Stack[fp + i.A + 0] = index;
// if ( Step > 0 and Index <= Limit ) or ( Step < 0 and Index >= Limit ) then Var = Index, relative jump sBx
if ((!step.LessThanOrEquals(zero) && index.LessThanOrEquals(limit)) ||
(step.LessThan(zero) && !index.LessThan(limit)))
{
thread.Stack[fp + i.A + 3] = index;
ip += i.sBx;
}
continue;
}
case Opcode.ForPrep:
{
LuaValue index = thread.Stack[fp + i.A + 0];
LuaValue limit = thread.Stack[fp + i.A + 1];
LuaValue step = thread.Stack[fp + i.A + 2];
// Convert for control variables to numbers.
if (!index.TryToNumberValue(out index))
{
throw new InvalidOperationException("'for' initial value must be a number.");
}
if (!limit.TryToNumberValue(out limit))
{
throw new InvalidOperationException("'for' limit must be a number.");
}
if (!step.TryToNumberValue(out step))
{
throw new InvalidOperationException("'for' step must be a number.");
}
// Index -= Step
index = index.Subtract(step);
// Update thread.Stack.
thread.Stack[fp + i.A + 0] = index;
thread.Stack[fp + i.A + 1] = limit;
thread.Stack[fp + i.A + 2] = step;
// relative jump sBx
ip += i.sBx;
continue;
}
/* A + 0 Generator
* A + 1 State
* A + 2 Control
* A + 3 Var_1
* ...
* A + 3 + C Var_C
*/
case Opcode.TForLoop:
{
LuaValue generator = thread.Stack[fp + i.A + 0];
LuaValue state = thread.Stack[fp + i.A + 1];
LuaValue control = thread.Stack[fp + i.A + 2];
// Var_1, ..., Var_C := Generator( State, Control )
thread.Stack[fp + i.A + 3] = generator;
thread.Stack[fp + i.A + 4] = state;
thread.Stack[fp + i.A + 5] = control;
generator.Call(thread, fp + i.A + 3, 2, i.C);
// if Var_1 ~= nil then Control = Var_1 else skip associated jump
LuaValue var_1 = thread.Stack[fp + i.A + 3];
if (var_1 != null && var_1.IsTrue())
{
// Set control.
thread.Stack[fp + i.A + 2] = var_1;
// Perform associated jump.
i = prototype.Instructions[ip++];
ip += i.sBx;
}
else
{
ip += 1;
}
continue;
}
case Opcode.SetList:
{
// Special decoding.
int keyBase;
if (i.C != 0)
{
keyBase = i.C;
}
else
{
keyBase = prototype.Instructions[ip++].Index;
}
int lastKey;
if (i.B != 0)
{
lastKey = i.B;
}
else
{
lastKey = thread.Top - fp - i.A;
thread.Top = -1;
}
// R( A )[ ( C - 1 ) * 50 + i ] := R( A + i ), 1 <= i <= B
for (int key = 1; key <= lastKey; ++key)
{
thread.Stack[fp + i.A].NewIndex((keyBase - 1) * Instruction.FieldsPerFlush + key, thread.Stack[fp + i.A + key]);
}
if (i.B == 0)
{
thread.StackWatermark(fp + prototype.StackSize);
}
continue;
}
case Opcode.Close:
{
// close all thread.Stack variables from R( A ) to the top
thread.CloseUpVals(fp + i.A);
continue;
}
case Opcode.Closure:
{
// R( A ) := function closure from P( Bx )
LuaFunction function = new LuaFunction(prototype.Prototypes[i.Bx], Environment);
thread.Stack[fp + i.A] = function;
// followed by upval initialization with Move or GetUpVal
for (int upval = 0; upval < function.prototype.UpValCount; ++upval)
{
Instruction u = prototype.Instructions[ip++];
if (u.Opcode == Opcode.Move)
{
function.upVals[upval] = thread.MakeUpVal(fp + u.B);
}
else if (u.Opcode == Opcode.GetUpVal)
{
function.upVals[upval] = upVals[u.B];
}
else
{
throw new InvalidProgramException("Malformed upval initialization bytecode.");
}
}
continue;
}
case Opcode.Vararg:
{
// R( A ), ..., R( A + B - 1 ) = vararg
/* frameBase --> Function
* ^ null
* argumentCount null
* v argument (vararg)
* framePointer --> argument
* argument
*/
// Find varargs.
int varargBase = frameBase + 1 + prototype.ParameterCount;
int varargCount = Math.Max(fp - varargBase, 0);
// Find how many we want.
int copyCount;
if (i.B != 0)
{
copyCount = Math.Min(i.B, varargCount);
}
else
{
copyCount = varargCount;
thread.Top = fp + i.A + copyCount - 1;
thread.StackWatermark(Math.Max(fp + prototype.StackSize, thread.Top + 1));
}
// Copy into correct position.
for (int vararg = 0; vararg < copyCount; ++vararg)
{
thread.Stack[fp + i.A + vararg] = thread.Stack[varargBase + vararg];
}
for (int vararg = copyCount; vararg < i.B; ++vararg)
{
thread.Stack[fp + i.A + vararg] = null;
}
continue;
}
case Opcode.IntDiv:
{
// R( A ) := RK( B ) \ RK( C )
thread.Stack[fp + i.A] = RK(thread.Stack, fp, i.B).IntegerDivide(RK(thread.Stack, fp, i.C));
continue;
}
}
}
}
catch (Exception e)
{
thread.UnwoundFrames.Add(new Frame(frameBase, resultCount, fp, ip));
throw e;
}
}