- Added a new intrinsic for class pointers to check if the class is abstract (#1308)

src/common/engine/namedef.h

@@ -305,6 +305,7 @@ xx(BuiltinNew)
 xx(GetClass)
 xx(GetParentClass)
 xx(GetClassName)
+xx(IsAbstract)
 xx(GetDefaultByType)
 xx(Exp)
 xx(Log10)

src/common/scripting/backend/codegen.cpp

@@ -8256,6 +8256,14 @@ FxExpression *FxMemberFunctionCall::Resolve(FCompileContext& ctx)
 			return x->Resolve(ctx);
 		}
 	}
+	if (MethodName == NAME_IsAbstract && Self->ValueType->isClassPointer())
+	{
+		if (CheckArgSize(NAME_IsAbstract, ArgList, 0, 0, ScriptPosition))
+		{
+			auto x = new FxIsAbstract(Self);
+			return x->Resolve(ctx);
+		}
+	}
 
 	if (Self->ValueType->isRealPointer())
 	{
@@ -9252,6 +9260,47 @@ ExpEmit FxGetClassName::Emit(VMFunctionBuilder *build)
 //
 //==========================================================================
 
+FxIsAbstract::FxIsAbstract(FxExpression *self)
+	:FxExpression(EFX_IsAbstract, self->ScriptPosition)
+{
+	Self = self;
+}
+
+FxIsAbstract::~FxIsAbstract()
+{
+	SAFE_DELETE(Self);
+}
+
+FxExpression *FxIsAbstract::Resolve(FCompileContext &ctx)
+{
+	SAFE_RESOLVE(Self, ctx);
+
+	if (!Self->ValueType->isClassPointer())
+	{
+		ScriptPosition.Message(MSG_ERROR, "IsAbstract() requires a class pointer");
+		delete this;
+		return nullptr;
+	}
+	ValueType = TypeBool;
+	return this;
+}
+
+ExpEmit FxIsAbstract::Emit(VMFunctionBuilder *build)
+{
+	ExpEmit op = Self->Emit(build);
+	op.Free(build);
+
+	ExpEmit to(build, REGT_INT);
+	build->Emit(OP_LBU, to.RegNum, op.RegNum, build->GetConstantInt(myoffsetof(PClass, bAbstract)));
+
+	return to;
+}
+
+//==========================================================================
+//
+//
+//==========================================================================
+
 FxColorLiteral::FxColorLiteral(FArgumentList &args, FScriptPosition &sc)
 	:FxExpression(EFX_ColorLiteral, sc)
 {

src/common/scripting/backend/codegen.h

@@ -298,6 +298,7 @@ enum EFxType
 	EFX_GetClass,
 	EFX_GetParentClass,
 	EFX_GetClassName,
+	EFX_IsAbstract,
 	EFX_StrLen,
 	EFX_ColorLiteral,
 	EFX_GetDefaultByType,
@@ -1663,6 +1664,24 @@ public:
 	ExpEmit Emit(VMFunctionBuilder *build);
 };
 
+//==========================================================================
+//
+//	FxIsAbstract
+//
+//==========================================================================
+
+class FxIsAbstract : public FxExpression
+{
+	FxExpression* Self;
+
+public:
+
+	FxIsAbstract(FxExpression* self);
+	~FxIsAbstract();
+	FxExpression *Resolve(FCompileContext&);
+	ExpEmit Emit(VMFunctionBuilder* build);
+};
+
 //==========================================================================
 //
 //	FxColorLiteral