private Expression InlineIfTrueIfFalse(Compiler.SemanticNodes.BlockNode trueBlock, Compiler.SemanticNodes.BlockNode falseBlock)
{
NameBinding nilBinding = this.Context.GetBinding(SemanticConstants.Nil);
Expression testExpression = Expression.Convert(this.Receiver, typeof(bool));
Expression trueExpression;
if (trueBlock != null)
{
trueExpression = trueBlock.Accept(new InlineBlockVisitor(this));
}
else
{
trueExpression = nilBinding.GenerateReadExpression(this);
}
Expression falseExpression;
if (falseBlock != null)
{
falseExpression = falseBlock.Accept(new InlineBlockVisitor(this));
}
else
{
falseExpression = nilBinding.GenerateReadExpression(this);
}
Expression result = Expression.Condition(testExpression, trueExpression, falseExpression, typeof(object));
this.SetResult(result);
return(result);
}
private Expression InlineOr(Compiler.SemanticNodes.BlockNode block)
{
NameBinding trueBinding = this.Context.GetBinding(SemanticConstants.True);
Expression testExpression = Expression.Convert(this.Receiver, typeof(bool));
Expression blockExpression = block.Accept(new InlineBlockVisitor(this));
Expression result = Expression.Condition(testExpression, trueBinding.GenerateReadExpression(this), blockExpression, typeof(object));
this.SetResult(result);
return(result);
}
private Expression InlineToByDo(Expression start, Expression stop, Expression step, Compiler.SemanticNodes.BlockNode block)
{
/// to:by:do:
/* C# semantics of the inlining
* if ((start is int) && (stop is int) && (step is int))
* {
* int iStart, iStop, iStep;
* try
* {
* iStart = checked((int)start);
* iStop = checked((int)stop);
* iStep = checked((int)step);
* // This is to ensure the calculation below do not fail running unchecked
* int na = checked(iStart + iStep);
* na = checked(iStop + iStep);
* }
* catch (OverflowException)
* {
* goto Int32Overwlow;
* }
*
* if (iStep == 0)
* throw new ArgumentOutOfRangeException();
*
* if (iStep > 0)
* {
* do
* {
* if (iStart > iStop)
* goto Exit;
* block(iStart);
* iStart = iStart + iStep;
* } while (true);
* }
* else
* {
* do
* {
* if (iStop > iStart)
* goto Exit;
* block(iStart);
* iStart = iStart + iStep;
* } while (true);
* }
* }
* Int32Overwlow:
* // We could implement BigInteger optimization here, but too much work and probably not much to gain
* // Fallback to dynamic invocation
* dynamic dStart = start;
* dynamic dStep = step;
* if (dStep == 0)
* throw new ArgumentOutOfRangeException();
*
* if (dStep > 0)
* {
* do
* {
* if (dStart > stop)
* goto Exit;
* block(dStart);
* dStart = dStart + step;
* } while (true);
* }
* else
* {
* do
* {
* if (stop > dStart)
* goto Exit;
* block(dStart);
* dStart = dStart + step;
* } while (true);
* }
* Exit:
*/
NameBinding nilBinding = this.Context.GetBinding(SemanticConstants.Nil);
LabelTarget exitLabel = Expression.Label(typeof(void));
LabelTarget overflowLabel = Expression.Label(typeof(void));
ParameterExpression iStart = Expression.Variable(typeof(int), "iStart");
ParameterExpression iStop = Expression.Variable(typeof(int), "iStop");
ParameterExpression iStep = Expression.Variable(typeof(int), "iStep");
ParameterExpression iNA = Expression.Variable(typeof(int), "iNA");
InlineBlockVisitor visitor = new InlineBlockVisitor(this);
if (block.Arguments.Count > 0)
{
visitor.DefineExternalArgument(block.Arguments[0].Token.Value, Expression.Convert(iStart, typeof(object)));
}
Expression integerOperation = block.Accept(visitor);
Expression integerTest = Expression.AndAlso(Expression.AndAlso(
Expression.TypeIs(start, typeof(int)), Expression.TypeIs(stop, typeof(int))), Expression.TypeIs(step, typeof(int)));
Expression integerBlock = Expression.Block(
Expression.TryCatch(
Expression.Block(
Expression.Assign(iStart, Expression.ConvertChecked(start, typeof(int))),
Expression.Assign(iStop, Expression.ConvertChecked(stop, typeof(int))),
Expression.Assign(iStep, Expression.ConvertChecked(step, typeof(int))),
Expression.Assign(iNA, Expression.AddChecked(iStart, iStep)),
Expression.Assign(iNA, Expression.AddChecked(iStop, iStep))),
Expression.Catch(typeof(OverflowException), Expression.Goto(overflowLabel, typeof(int))),
Expression.Catch(typeof(InvalidCastException), Expression.Goto(overflowLabel, typeof(int)))),
Expression.IfThen(
Expression.Equal(iStep, Expression.Constant(0)),
Expression.Throw(Expression.New(typeof(ArgumentOutOfRangeException)), typeof(object))),
Expression.IfThenElse(
Expression.GreaterThan(iStep, Expression.Constant(0)),
Expression.Loop(
Expression.IfThenElse(
Expression.GreaterThan(iStart, iStop),
Expression.Break(exitLabel, nilBinding.GenerateReadExpression(this)),
Expression.Block(
integerOperation,
Expression.AddAssign(iStart, iStep)))),
Expression.Loop(
Expression.IfThenElse(
Expression.GreaterThan(iStop, iStart),
Expression.Break(exitLabel, nilBinding.GenerateReadExpression(this)),
Expression.Block(
integerOperation,
Expression.AddAssign(iStart, iStep))))));
ParameterExpression dStart = Expression.Variable(typeof(object), "dStart");
ParameterExpression dStep = Expression.Variable(typeof(object), "dStep");
visitor = new InlineBlockVisitor(this);
if (block.Arguments.Count > 0)
{
visitor.DefineExternalArgument(block.Arguments[0].Token.Value, dStart);
}
Expression dynamicOperation = block.Accept(visitor);
Expression dynamicBlock = Expression.Block(
Expression.Assign(dStart, start),
Expression.Assign(dStep, Expression.Convert(step, typeof(object))),
Expression.IfThen(
Expression.IsTrue(Expression.Convert(this.Context.CompileDynamicCall(this, "=", dStep, PreboxedConstants.Int32_00000000_Expression), typeof(bool))),
Expression.Throw(Expression.New(typeof(ArgumentOutOfRangeException)), typeof(object))),
Expression.IfThenElse(
Expression.IsTrue(Expression.Convert(this.Context.CompileDynamicCall(this, ">", dStep, PreboxedConstants.Int32_00000000_Expression), typeof(bool))),
Expression.Loop(
Expression.IfThenElse(
Expression.IsTrue(Expression.Convert(this.Context.CompileDynamicCall(this, ">", dStart, stop), typeof(bool))),
Expression.Break(exitLabel, nilBinding.GenerateReadExpression(this)),
Expression.Block(
dynamicOperation,
Expression.Assign(dStart, this.Context.CompileDynamicCall(this, "+", dStart, dStep))))),
Expression.Loop(
Expression.IfThenElse(
Expression.IsTrue(Expression.Convert(this.Context.CompileDynamicCall(this, ">", stop, dStart), typeof(bool))),
Expression.Break(exitLabel, nilBinding.GenerateReadExpression(this)),
Expression.Block(
dynamicOperation,
Expression.Assign(dStart, this.Context.CompileDynamicCall(this, "+", dStart, dStep)))))));
return(Expression.Block(
new ParameterExpression[] { iStart, iStop, iStep, iNA, dStart, dStep },
integerBlock,
Expression.Label(overflowLabel),
dynamicBlock,
Expression.Label(exitLabel),
nilBinding.GenerateReadExpression(this)));
}