public override void Emit(EmitContext ec) { if (IsBitwiseBoolean && UserOperator == null) { EmitBitwiseBoolean(ec); return; } if ((Binary.Oper & Binary.Operator.EqualityMask) != 0) { EmitEquality(ec); return; } Label is_null_label = ec.DefineLabel(); Label end_label = ec.DefineLabel(); if (ec.HasSet(BuilderContext.Options.AsyncBody) && Right.ContainsEmitWithAwait()) { Left = Left.EmitToField(ec); Right = Right.EmitToField(ec); } if (UnwrapLeft != null) { UnwrapLeft.EmitCheck(ec); } // // Don't emit HasValue check when left and right expressions are same // if (UnwrapRight != null && !Binary.Left.Equals(Binary.Right)) { UnwrapRight.EmitCheck(ec); if (UnwrapLeft != null) { ec.Emit(OpCodes.And); } } ec.Emit(OpCodes.Brfalse, is_null_label); if (UserOperator != null) { var args = new Arguments(2); args.Add(new Argument(Left)); args.Add(new Argument(Right)); var call = new CallEmitter(); call.EmitPredefined(ec, UserOperator, args); } else { Binary.EmitOperator(ec, Left, Right); } // // Wrap the result when the operator return type is nullable type // if (type.IsNullableType) { ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); } ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(is_null_label); if ((Binary.Oper & Binary.Operator.ComparisonMask) != 0) { ec.EmitInt(0); } else { LiftedNull.Create(type, loc).Emit(ec); } ec.MarkLabel(end_label); }
void EmitBitwiseBoolean(EmitContext ec) { Label load_left = ec.DefineLabel(); Label load_right = ec.DefineLabel(); Label end_label = ec.DefineLabel(); Label is_null_label = ec.DefineLabel(); bool or = Binary.Oper == Binary.Operator.BitwiseOr; // // Both operands are bool? types // if (UnwrapLeft != null && UnwrapRight != null) { if (ec.HasSet(BuilderContext.Options.AsyncBody) && Binary.Right.ContainsEmitWithAwait()) { Left = Left.EmitToField(ec); Right = Right.EmitToField(ec); } else { UnwrapLeft.Store(ec); UnwrapRight.Store(ec); } Left.Emit(ec); ec.Emit(OpCodes.Brtrue_S, load_right); Right.Emit(ec); ec.Emit(OpCodes.Brtrue_S, load_left); UnwrapLeft.EmitCheck(ec); ec.Emit(OpCodes.Brfalse_S, load_right); // load left ec.MarkLabel(load_left); if (or) { UnwrapRight.Load(ec); } else { UnwrapLeft.Load(ec); } ec.Emit(OpCodes.Br_S, end_label); // load right ec.MarkLabel(load_right); if (or) { UnwrapLeft.Load(ec); } else { UnwrapRight.Load(ec); } ec.MarkLabel(end_label); return; } // // Faster version when one operand is bool // if (UnwrapLeft == null) { // // (bool, bool?) // // Optimizes remaining (false & bool?), (true | bool?) which are not easy to handle // in binary expression reduction // var c = Left as BoolConstant; if (c != null) { // Keep evaluation order UnwrapRight.Store(ec); ec.EmitInt(or ? 1 : 0); ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); } else if (Left.IsNull) { UnwrapRight.Emit(ec); ec.Emit(or ? OpCodes.Brfalse_S : OpCodes.Brtrue_S, is_null_label); UnwrapRight.Load(ec); ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(is_null_label); LiftedNull.Create(type, loc).Emit(ec); } else { Left.Emit(ec); ec.Emit(or ? OpCodes.Brfalse_S : OpCodes.Brtrue_S, load_right); ec.EmitInt(or ? 1 : 0); ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(load_right); UnwrapRight.Original.Emit(ec); } } else { // // (bool?, bool) // // Keep left-right evaluation order UnwrapLeft.Store(ec); // // Optimizes remaining (bool? & false), (bool? | true) which are not easy to handle // in binary expression reduction // var c = Right as BoolConstant; if (c != null) { ec.EmitInt(or ? 1 : 0); ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); } else if (Right.IsNull) { UnwrapLeft.Emit(ec); ec.Emit(or ? OpCodes.Brfalse_S : OpCodes.Brtrue_S, is_null_label); UnwrapLeft.Load(ec); ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(is_null_label); LiftedNull.Create(type, loc).Emit(ec); } else { Right.Emit(ec); ec.Emit(or ? OpCodes.Brfalse_S : OpCodes.Brtrue_S, load_right); ec.EmitInt(or ? 1 : 0); ec.Emit(OpCodes.Newobj, NullableInfo.GetConstructor(type)); ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(load_right); UnwrapLeft.Load(ec); } } ec.MarkLabel(end_label); }
// // Emits optimized equality or inequality operator when possible // void EmitEquality(EmitContext ec) { // // Either left or right is null // if (UnwrapLeft != null && Binary.Right.IsNull) // TODO: Optimize for EmitBranchable // // left.HasValue == false // { UnwrapLeft.EmitCheck(ec); if (Binary.Oper == Binary.Operator.Equality) { ec.EmitInt(0); ec.Emit(OpCodes.Ceq); } return; } if (UnwrapRight != null && Binary.Left.IsNull) { // // right.HasValue == false // UnwrapRight.EmitCheck(ec); if (Binary.Oper == Binary.Operator.Equality) { ec.EmitInt(0); ec.Emit(OpCodes.Ceq); } return; } Label dissimilar_label = ec.DefineLabel(); Label end_label = ec.DefineLabel(); if (UserOperator != null) { var left = Left; if (UnwrapLeft != null) { UnwrapLeft.EmitCheck(ec); } else { // Keep evaluation order same if (!(Left is VariableReference)) { Left.Emit(ec); var lt = new LocalTemporary(Left.Type); lt.Store(ec); left = lt; } } if (UnwrapRight != null) { UnwrapRight.EmitCheck(ec); if (UnwrapLeft != null) { ec.Emit(OpCodes.Bne_Un, dissimilar_label); Label compare_label = ec.DefineLabel(); UnwrapLeft.EmitCheck(ec); ec.Emit(OpCodes.Brtrue, compare_label); if (Binary.Oper == Binary.Operator.Equality) { ec.EmitInt(1); } else { ec.EmitInt(0); } ec.Emit(OpCodes.Br, end_label); ec.MarkLabel(compare_label); } else { ec.Emit(OpCodes.Brfalse, dissimilar_label); } } else { ec.Emit(OpCodes.Brfalse, dissimilar_label); } var args = new Arguments(2); args.Add(new Argument(left)); args.Add(new Argument(Right)); var call = new CallEmitter(); call.EmitPredefined(ec, UserOperator, args); } else { if (ec.HasSet(BuilderContext.Options.AsyncBody) && Binary.Right.ContainsEmitWithAwait()) { Left = Left.EmitToField(ec); Right = Right.EmitToField(ec); } // // Emit underlying value comparison first. // // For this code: int? a = 1; bool b = a == 1; // // We emit something similar to this. Expressions with side effects have local // variable created by Unwrap expression // // left.GetValueOrDefault () // right // bne.un.s dissimilar_label // left.HasValue // br.s end_label // dissimilar_label: // ldc.i4.0 // end_label: // Left.Emit(ec); Right.Emit(ec); ec.Emit(OpCodes.Bne_Un_S, dissimilar_label); // // Check both left and right expressions for Unwrap call in which // case we need to run get_HasValue() check because the type is // nullable and could have null value // if (UnwrapLeft != null) { UnwrapLeft.EmitCheck(ec); } if (UnwrapRight != null) { UnwrapRight.EmitCheck(ec); } if (UnwrapLeft != null && UnwrapRight != null) { if (Binary.Oper == Binary.Operator.Inequality) { ec.Emit(OpCodes.Xor); } else { ec.Emit(OpCodes.Ceq); } } else { if (Binary.Oper == Binary.Operator.Inequality) { ec.EmitInt(0); ec.Emit(OpCodes.Ceq); } } } ec.Emit(OpCodes.Br_S, end_label); ec.MarkLabel(dissimilar_label); if (Binary.Oper == Binary.Operator.Inequality) { ec.EmitInt(1); } else { ec.EmitInt(0); } ec.MarkLabel(end_label); }