protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
var labelNs = @"Or\" + Guid.NewGuid().ToString("N");
var trueLabel = @"True\" + labelNs;
var falseLabel = @"False\" + labelNs;
var evalLabel = @"Eval\" + labelNs;
EmitCode(target, trueLabel, falseLabel);
if (stackSemantics == StackSemantics.Value)
{
target.EmitLabel(Position, falseLabel);
target.EmitConstant(Position, false);
target.EmitJump(Position, evalLabel);
target.EmitLabel(Position, trueLabel);
target.EmitConstant(Position, true);
target.EmitLabel(Position, evalLabel);
}
else
{
Debug.Assert(stackSemantics == StackSemantics.Effect);
target.EmitLabel(Position, falseLabel);
target.EmitLabel(Position, trueLabel);
}
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
if(stackSemantics == StackSemantics.Value)
throw new NotSupportedException("While loops do not produce values and can thus not be used as expressions.");
if (!IsInitialized)
throw new PrexoniteException("AstWhileLoop requires Condition to be set.");
//Optimize unary not condition
_OptimizeNode(target, ref Condition);
// Invert condition when unary logical not
AstIndirectCall unaryCond;
while (Condition.IsCommandCall(Commands.Core.Operators.LogicalNot.DefaultAlias, out unaryCond))
{
Condition = unaryCond.Arguments[0];
IsPositive = !IsPositive;
}
//Constant conditions
var conditionIsConstant = false;
if (Condition is AstConstant)
{
var constCond = (AstConstant) Condition;
PValue condValue;
if (
!constCond.ToPValue(target).TryConvertTo(
target.Loader, PType.Bool, out condValue))
goto continueFull;
else if ((bool) condValue.Value == IsPositive)
conditionIsConstant = true;
else
{
//Condition is always false
if (!IsPrecondition) //If do-while, emit the body without loop code
{
target.BeginBlock(Block);
Block.EmitEffectCode(target);
target.EndBlock();
}
return;
}
}
continueFull:
target.BeginBlock(Block);
if (!Block.IsEmpty) //Body exists -> complete loop code?
{
if (conditionIsConstant) //Infinite, hopefully user managed, loop ->
{
target.EmitLabel(Position, Block.ContinueLabel);
target.EmitLabel(Position, Block.BeginLabel);
Block.EmitEffectCode(target);
target.EmitJump(Position, Block.ContinueLabel);
}
else
{
if (IsPrecondition)
target.EmitJump(Position, Block.ContinueLabel);
target.EmitLabel(Position, Block.BeginLabel);
Block.EmitEffectCode(target);
_emitCondition(target);
}
}
else //Body does not exist -> Condition loop
{
target.EmitLabel(Position, Block.BeginLabel);
_emitCondition(target);
}
target.EmitLabel(Position, Block.BreakLabel);
target.EndBlock();
}
private void _emitCondition(CompilerTarget target)
{
target.EmitLabel(Position, Block.ContinueLabel);
AstLazyLogical.EmitJumpCondition(target, Condition, Block.BeginLabel, IsPositive);
}
protected override void DoEmitCode(CompilerTarget target, string trueLabel,
string falseLabel)
{
var labelNs = @"Or\" + Guid.NewGuid().ToString("N");
var nextLabel = @"Next\" + labelNs;
foreach (var expr in Conditions)
{
var and = expr as AstLogicalAnd;
if (and != null)
{
and.EmitCode(target, trueLabel, nextLabel);
//ResolveOperator pending jumps to Next
target.EmitLabel(Position, nextLabel);
target.FreeLabel(nextLabel);
//Future references of to nextLabel will be resolved in the next iteration
}
else
{
expr.EmitValueCode(target);
target.EmitJumpIfTrue(Position, trueLabel);
}
}
target.EmitJump(Position, falseLabel);
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
if(stackSemantics == StackSemantics.Value)
throw new NotSupportedException("Foreach loops don't produce values and can thus not be emitted with value semantics.");
if (!IsInitialized)
throw new PrexoniteException("AstForeachLoop requires List and Element to be set.");
//Optimize expression
_OptimizeNode(target, ref List);
//Create the enumerator variable
var enumVar = Block.CreateLabel("enumerator");
target.Function.Variables.Add(enumVar);
//Create the element assignment statement
var element = Element.GetCopy();
AstExpr optElem;
if (element.TryOptimize(target, out optElem))
{
element = optElem as AstGetSet;
if (element == null)
{
target.Loader.ReportMessage(Message.Error(Resources.AstForeachLoop_DoEmitCode_ElementTooComplicated,Position,MessageClasses.ForeachElementTooComplicated));
return;
}
}
var ldEnumVar = target.Factory.Call(Position, EntityRef.Variable.Local.Create(enumVar));
var getCurrent =
new AstGetSetMemberAccess(File, Line, Column, ldEnumVar, "Current");
element.Arguments.Add(getCurrent);
element.Call = PCall.Set;
//Actual Code Generation
var moveNextAddr = -1;
var getCurrentAddr = -1;
var disposeAddr = -1;
//Get the enumerator
target.BeginBlock(Block);
List.EmitValueCode(target);
target.EmitGetCall(List.Position, 0, "GetEnumerator");
var castAddr = target.Code.Count;
target.Emit(List.Position, OpCode.cast_const, "Object(\"System.Collections.IEnumerator\")");
target.EmitStoreLocal(List.Position, enumVar);
//check whether an enhanced CIL implementation is possible
bool emitHint;
if (element.DefaultAdditionalArguments + element.Arguments.Count > 1)
//has additional arguments
emitHint = false;
else
emitHint = true;
var @try = new AstTryCatchFinally(Position, Block);
@try.TryBlock = new AstActionBlock
(
Position, @try,
delegate
{
target.EmitJump(Position, Block.ContinueLabel);
//Assignment (begin)
target.EmitLabel(Position, Block.BeginLabel);
getCurrentAddr = target.Code.Count;
element.EmitEffectCode(target);
//Code block
Block.EmitEffectCode(target);
//Condition (continue)
target.EmitLabel(Position, Block.ContinueLabel);
moveNextAddr = target.Code.Count;
target.EmitLoadLocal(List.Position, enumVar);
target.EmitGetCall(List.Position, 0, "MoveNext");
target.EmitJumpIfTrue(Position, Block.BeginLabel);
//Break
target.EmitLabel(Position, Block.BreakLabel);
});
@try.FinallyBlock = new AstActionBlock
(
Position, @try,
delegate
{
disposeAddr = target.Code.Count;
target.EmitLoadLocal(List.Position, enumVar);
target.EmitCommandCall(List.Position, 1, Engine.DisposeAlias, true);
});
@try.EmitEffectCode(target);
target.EndBlock();
if (getCurrentAddr < 0 || moveNextAddr < 0 || disposeAddr < 0)
throw new PrexoniteException(
"Could not capture addresses within foreach construct for CIL compiler hint.");
else if (emitHint)
{
var hint = new ForeachHint(enumVar, castAddr, getCurrentAddr, moveNextAddr,
disposeAddr);
Cil.Compiler.AddCilHint(target, hint);
Action<int, int> mkHook =
(index, original) =>
{
AddressChangeHook hook = null;
hook = new AddressChangeHook(
original,
newAddr =>
{
foreach (
var hintEntry in target.Meta[Loader.CilHintsKey].List)
{
var entry = hintEntry.List;
if (entry[0] == ForeachHint.Key &&
entry[index].Text == original.ToString(CultureInfo.InvariantCulture))
{
entry[index] = newAddr.ToString(CultureInfo.InvariantCulture);
// AddressChangeHook.ctor can be trusted not to call the closure.
// ReSharper disable PossibleNullReferenceException
// ReSharper disable AccessToModifiedClosure
hook.InstructionIndex = newAddr;
// ReSharper restore AccessToModifiedClosure
// ReSharper restore PossibleNullReferenceException
original = newAddr;
}
}
});
target.AddressChangeHooks.Add(hook);
};
mkHook(ForeachHint.CastAddressIndex + 1, castAddr);
mkHook(ForeachHint.GetCurrentAddressIndex + 1, getCurrentAddr);
mkHook(ForeachHint.MoveNextAddressIndex + 1, moveNextAddr);
mkHook(ForeachHint.DisposeAddressIndex + 1, disposeAddr);
} // else nothing
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
if(stackSemantics == StackSemantics.Value)
throw new NotSupportedException("Try-catch-finally blocks cannot be used with value stack semantics (They don't produce values)");
var prefix = "try\\" + Guid.NewGuid().ToString("N") + "\\";
var beginTryLabel = prefix + "beginTry";
var beginFinallyLabel = prefix + "beginFinally";
var beginCatchLabel = prefix + "beginCatch";
var endTry = prefix + "endTry";
if (TryBlock.IsEmpty)
if (FinallyBlock.IsEmpty)
return;
else
{
//The finally block is not protected
// A trycatchfinally with just a finally block is equivalent to the contents of the finally block
// " try {} finally { $code } " => " $code "
FinallyBlock.EmitEffectCode(target);
return;
}
//Emit try block
target.EmitLabel(Position, beginTryLabel);
target.Emit(Position,OpCode.@try);
TryBlock.EmitEffectCode(target);
//Emit finally block
target.EmitLabel(FinallyBlock.Position, beginFinallyLabel);
var beforeEmit = target.Code.Count;
FinallyBlock.EmitEffectCode(target);
if (FinallyBlock.Count > 0 && target.Code.Count == beforeEmit)
target.Emit(FinallyBlock.Position, OpCode.nop);
target.EmitLeave(FinallyBlock.Position, endTry);
//Emit catch block
target.EmitLabel(CatchBlock.Position, beginCatchLabel);
var usesException = ExceptionVar != null;
var justRethrow = CatchBlock.IsEmpty && !usesException;
if (usesException)
{
//Assign exception
ExceptionVar = _GetOptimizedNode(target, ExceptionVar) as AstGetSet ?? ExceptionVar;
ExceptionVar.Arguments.Add(new AstGetException(File, Line, Column));
ExceptionVar.Call = PCall.Set;
ExceptionVar.EmitEffectCode(target);
}
if (!justRethrow)
{
//Exception handled
CatchBlock.EmitEffectCode(target);
}
else
{
//Exception not handled => rethrow.
// * Rethrow is implemented in the runtime *
//AstThrow th = new AstThrow(File, Line, Column);
//th.Expression = new AstGetException(File, Line, Column);
//th.EmitCode(target);
}
target.EmitLabel(Position, endTry);
target.Emit(Position,OpCode.nop);
var block =
new TryCatchFinallyBlock(
_getAddress(target, beginTryLabel), _getAddress(target, endTry))
{
BeginFinally =
(!FinallyBlock.IsEmpty ? _getAddress(target, beginFinallyLabel) : -1),
BeginCatch = (!justRethrow ? _getAddress(target, beginCatchLabel) : -1),
UsesException = usesException
};
//Register try-catch-finally block
target.Function.Meta.AddTo(TryCatchFinallyBlock.MetaKey, block);
target.Function.InvalidateTryCatchFinallyBlocks();
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
if(stackSemantics == StackSemantics.Value)
throw new NotSupportedException("For loops don't produce values and can thus not be emitted with value semantics.");
if (!IsInitialized)
throw new PrexoniteException("AstForLoop requires Condition to be set.");
//Optimize unary not condition
var condition = Condition;
_OptimizeNode(target, ref condition);
// Invert condition when unary logical not
AstIndirectCall unaryCond;
while (Condition.IsCommandCall(Commands.Core.Operators.LogicalNot.DefaultAlias, out unaryCond))
{
Condition = unaryCond.Arguments[0];
IsPositive = !IsPositive;
}
//Constant conditions
var conditionIsConstant = false;
var constCond = condition as AstConstant;
if (constCond != null)
{
PValue condValue;
if (
!constCond.ToPValue(target).TryConvertTo(
target.Loader, PType.Bool, out condValue))
goto continueFull;
else if ((bool) condValue.Value == IsPositive)
conditionIsConstant = true;
else
{
//Condition is always false
return;
}
}
continueFull:
var conditionLabel = Block.CreateLabel("condition");
if (!Block.IsEmpty) //Body exists -> complete loop code?
{
if (conditionIsConstant) //Infinite, hopefully user managed, loop ->
{
/* {init}
* begin:
* {block}
* continue:
* {next}
* jump -> begin
*/
target.BeginBlock(Initialize);
Initialize.EmitValueCode(target);
if (!IsPrecondition) //start with nextIteration
target.EmitJump(Position, Block.ContinueLabel);
target.EmitLabel(Position, Block.BeginLabel);
target.BeginBlock(NextIteration);
target.BeginBlock(Block);
Block.EmitEffectCode(target);
target.EndBlock();
target.EmitLabel(Position, Block.ContinueLabel);
NextIteration.EmitValueCode(target);
target.EndBlock();
target.EmitJump(Position, Block.BeginLabel);
target.EndBlock();
}
else //Variable condition and body -> full loop code
{
/* {init}
* jump -> condition
* begin:
* {block}
* continue:
* {next}
* condition:
* {condition}
* jump if true -> begin
*/
target.BeginBlock(Initialize);
Initialize.EmitValueCode(target);
target.BeginBlock(NextIteration);
if (IsPrecondition)
target.EmitJump(Position, conditionLabel);
else
target.EmitJump(Position, Block.ContinueLabel);
target.EmitLabel(Position, Block.BeginLabel);
target.BeginBlock(Block);
Block.EmitEffectCode(target);
target.EndBlock();
target.EmitLabel(Position, Block.ContinueLabel);
NextIteration.EmitValueCode(target);
target.EndBlock();
target.EmitLabel(Position, conditionLabel);
AstLazyLogical.EmitJumpCondition(
target, condition, Block.BeginLabel, IsPositive);
target.EndBlock();
}
}
else //Body does not exist -> Condition loop
{
/* {init}
* begin:
* {cond}
* jump if false -> break
* continue:
* {next}
* jump -> begin
*/
target.BeginBlock(Block);
Initialize.EmitValueCode(target);
if (!IsPrecondition)
target.EmitJump(Position, Block.ContinueLabel);
target.EmitLabel(Position, Block.BeginLabel);
AstLazyLogical.EmitJumpCondition(target, condition, Block.BreakLabel, !IsPositive);
if (IsPrecondition)
target.EmitLabel(Position, Block.ContinueLabel);
NextIteration.EmitValueCode(target);
target.EmitJump(Position, Block.BeginLabel);
target.EndBlock();
}
target.EmitLabel(Position, Block.BreakLabel);
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
target.EmitLabel(Position, Label);
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
//Optimize condition
_OptimizeNode(target, ref Condition);
// Invert condition when unary logical not
AstIndirectCall unaryCond;
while (Condition.IsCommandCall(Commands.Core.Operators.LogicalNot.DefaultAlias, out unaryCond))
{
Condition = unaryCond.Arguments[0];
IsNegative = !IsNegative;
}
//Constant conditions
if (Condition is AstConstant)
{
var constCond = (AstConstant) Condition;
PValue condValue;
if (
!constCond.ToPValue(target).TryConvertTo(
target.Loader, PType.Bool, out condValue))
goto continueFull;
else if (((bool) condValue.Value) ^ IsNegative)
IfBlock.EmitEffectCode(target);
else
ElseBlock.EmitEffectCode(target);
return;
}
//Conditions with empty blocks
if (IfBlock.IsEmpty && ElseBlock.IsEmpty)
{
Condition.EmitEffectCode(target);
return;
}
continueFull:
;
//Switch If and Else block in case the if-block is empty
if (IfBlock.IsEmpty)
{
IsNegative = !IsNegative;
var tmp = IfBlock;
IfBlock = ElseBlock;
ElseBlock = tmp;
}
var elseLabel = "else\\" + _depth + "\\assembler";
var endLabel = "endif\\" + _depth + "\\assembler";
_depth++;
//Emit
var ifGoto = IfBlock.IsSingleStatement
? IfBlock[0] as AstExplicitGoTo
: null;
var elseGoto = ElseBlock.IsSingleStatement
? ElseBlock[0] as AstExplicitGoTo
: null;
;
var ifIsGoto = ifGoto != null;
var elseIsGoto = elseGoto != null;
if (ifIsGoto && elseIsGoto)
{
//only jumps
AstLazyLogical.EmitJumpCondition(
target,
Condition,
ifGoto.Destination,
elseGoto.Destination,
!IsNegative);
}
else if (ifIsGoto)
{
//if => jump / else => block
AstLazyLogical.EmitJumpCondition(target, Condition, ifGoto.Destination, !IsNegative);
ElseBlock.EmitEffectCode(target);
}
else if (elseIsGoto)
{
//if => block / else => jump
AstLazyLogical.EmitJumpCondition(
target, Condition, elseGoto.Destination, IsNegative); //inverted
IfBlock.EmitEffectCode(target);
}
else
{
//if => block / else => block
AstLazyLogical.EmitJumpCondition(target, Condition, elseLabel, IsNegative);
IfBlock.EmitEffectCode(target);
target.EmitJump(Position, endLabel);
target.EmitLabel(Position, elseLabel);
ElseBlock.EmitEffectCode(target);
target.EmitLabel(Position, endLabel);
}
target.FreeLabel(elseLabel);
target.FreeLabel(endLabel);
}
public static void EmitJumpUnlessCondition(
CompilerTarget target, AstExpr cond, string targetLabel)
{
if (cond == null)
throw new ArgumentNullException("cond", Resources.AstLazyLogical__Condition_must_not_be_null);
if (target == null)
throw new ArgumentNullException("target", Resources.AstNode_Compiler_target_must_not_be_null);
if (String.IsNullOrEmpty(targetLabel))
throw new ArgumentException(
Resources.AstLazyLogical__targetLabel_must_neither_be_null_nor_empty, "targetLabel");
var logical = cond as AstLazyLogical;
if (logical != null)
{
var continueLabel = "Continue\\Lazy\\" + Guid.NewGuid().ToString("N");
logical.EmitCode(target, continueLabel, targetLabel); //inverted
target.EmitLabel(cond.Position, continueLabel);
}
else
{
cond.EmitValueCode(target);
target.EmitJumpIfFalse(cond.Position, targetLabel);
}
}
public void DoEmitPartialApplicationCode(CompilerTarget target)
{
AstPlaceholder.DeterminePlaceholderIndices(Expressions.OfType<AstPlaceholder>());
var count = Expressions.Count;
if (count == 0)
{
this.ConstFunc(null).EmitValueCode(target);
return;
}
//only the very last condition may be a placeholder
for (var i = 0; i < count; i++)
{
var value = Expressions[i];
var isPlaceholder = value.IsPlaceholder();
if (i == count - 1)
{
if (!isPlaceholder)
{
//there is no placeholder at all, wrap expression in const
Debug.Assert(Expressions.All(e => !e.IsPlaceholder()));
DoEmitCode(target,StackSemantics.Value);
target.EmitCommandCall(Position, 1, Const.Alias);
return;
}
}
else
{
if (isPlaceholder)
{
_reportInvalidPlaceholders(target);
return;
}
}
}
if (count == 0)
{
this.ConstFunc().EmitValueCode(target);
}
else if (count == 1)
{
Debug.Assert(Expressions[0].IsPlaceholder(),
"Singleton ??-chain expected to consist of placeholder.");
var placeholder = (AstPlaceholder) Expressions[0];
placeholder.IdFunc().EmitValueCode(target);
}
else
{
Debug.Assert(Expressions[count - 1].IsPlaceholder(),
"Last expression in ??-chain expected to be placeholder.");
var placeholder = (AstPlaceholder) Expressions[count - 1];
var prefix = new AstCoalescence(File, Line, Column);
prefix.Expressions.AddRange(Expressions.Take(count - 1));
//check for null (keep a copy of prefix on stack)
var constLabel = _generateEndLabel();
var endLabel = _generateEndLabel();
prefix._emitCode(target, constLabel, StackSemantics.Value);
target.EmitDuplicate(Position);
target.Emit(Position,OpCode.check_null);
target.EmitJumpIfFalse(Position, constLabel);
//prefix is null, identity function
target.EmitPop(Position);
placeholder.IdFunc().EmitValueCode(target);
target.EmitJump(Position, endLabel);
//prefix is not null, const function
target.EmitLabel(Position, constLabel);
target.EmitCommandCall(Position, 1, Const.Alias);
target.EmitLabel(Position, endLabel);
}
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
//Expressions contains at least two expressions
var endLabel = _generateEndLabel();
_emitCode(target, endLabel, stackSemantics);
target.EmitLabel(Position, endLabel);
}
protected override void DoEmitCode(CompilerTarget target, StackSemantics stackSemantics)
{
//Optimize condition
_OptimizeNode(target, ref Condition);
_OptimizeNode(target, ref IfExpression);
_OptimizeNode(target, ref ElseExpression);
var elseLabel = "elsei\\" + _depth + "\\assembler";
var endLabel = "endifi\\" + _depth + "\\assembler";
_depth++;
//Emit
//if => block / else => block
AstLazyLogical.EmitJumpCondition(target, Condition, elseLabel, IsNegative);
IfExpression.EmitCode(target, stackSemantics);
target.EmitJump(Position, endLabel);
target.EmitLabel(Position, elseLabel);
ElseExpression.EmitCode(target, stackSemantics);
target.EmitLabel(Position, endLabel);
target.FreeLabel(elseLabel);
target.FreeLabel(endLabel);
}