diff options
Diffstat (limited to 'src/xmlpatterns/expr/quserfunctioncallsite.cpp')
| -rw-r--r-- | src/xmlpatterns/expr/quserfunctioncallsite.cpp | 245 |
1 files changed, 245 insertions, 0 deletions
diff --git a/src/xmlpatterns/expr/quserfunctioncallsite.cpp b/src/xmlpatterns/expr/quserfunctioncallsite.cpp new file mode 100644 index 0000000..4e81484 --- /dev/null +++ b/src/xmlpatterns/expr/quserfunctioncallsite.cpp @@ -0,0 +1,245 @@ +/**************************************************************************** +** +** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtXmlPatterns module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qcommonsequencetypes_p.h" +#include "qdynamiccontextstore_p.h" +#include "qevaluationcache_p.h" + +#include "quserfunctioncallsite_p.h" + +QT_BEGIN_NAMESPACE + +using namespace QPatternist; + +UserFunctionCallsite::UserFunctionCallsite(const QXmlName nameP, + const FunctionSignature::Arity ar) : CallSite(nameP) + , m_arity(ar) + , m_expressionSlotOffset(-2) + +{ +} + +Item::Iterator::Ptr UserFunctionCallsite::evaluateSequence(const DynamicContext::Ptr &context) const +{ + return m_body->evaluateSequence(bindVariables(context)); +} + +Item UserFunctionCallsite::evaluateSingleton(const DynamicContext::Ptr &context) const +{ + return m_body->evaluateSingleton(bindVariables(context)); +} + +bool UserFunctionCallsite::evaluateEBV(const DynamicContext::Ptr &context) const +{ + return m_body->evaluateEBV(bindVariables(context)); +} + +void UserFunctionCallsite::evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const +{ + m_body->evaluateToSequenceReceiver(bindVariables(context)); +} + +DynamicContext::Ptr UserFunctionCallsite::bindVariables(const DynamicContext::Ptr &context) const +{ + const DynamicContext::Ptr stackContext(context->createStack()); + Q_ASSERT(stackContext); + + const Expression::List::const_iterator end(m_operands.constEnd()); + Expression::List::const_iterator it(m_operands.constBegin()); + + VariableSlotID slot = m_expressionSlotOffset; + + for(; it != end; ++it) + { + stackContext->setExpressionVariable(slot, + Expression::Ptr(new DynamicContextStore(*it, context))); + ++slot; + } + + return stackContext; +} + +SequenceType::List UserFunctionCallsite::expectedOperandTypes() const +{ + SequenceType::List result; + + if(m_functionDeclaration) + { + const FunctionArgument::List args(m_functionDeclaration->signature()->arguments()); + const FunctionArgument::List::const_iterator end(args.constEnd()); + FunctionArgument::List::const_iterator it(args.constBegin()); + + for(; it != end; ++it) + result.append((*it)->type()); + } + else + result.append(CommonSequenceTypes::ZeroOrMoreItems); + + return result; +} + +Expression::Ptr UserFunctionCallsite::typeCheck(const StaticContext::Ptr &context, + const SequenceType::Ptr &reqType) +{ + /* The parser calls TypeChecker::applyFunctionConversion() on user function + * bodies, possibly indirectly, before all function call sites have been + * resolved. Hence it's possible that we're called before before the usual + * typeCheck() pass, and hence before we have been resolved/checked and + * subsequently m_functionDeclaration set. Therefore, encounter for that below. + * + * UnresolvedVariableReference::typeCheck() has the same dilemma. + */ + + /* Ensure that the return value of the function is properly + * converted/does match from where it is called(which is here). */ + if(isRecursive() || !m_functionDeclaration) + return CallSite::typeCheck(context, reqType); + else + { + /* Update, such that we use a recent version of the body that has typeCheck() + * and compress() rewrites included. */ + m_body = m_functionDeclaration->body(); + + /* Note, we can't assign to m_functionDeclaration->body() because UserFunction can apply + * to several different callsites. Hence we need our own version. */ + m_body = m_body->typeCheck(context, reqType); + + /* We just act as a pipe for m_body, so we don't have to typecheck ourselves. However, + * the arguments must match the function declaration. */ + typeCheckOperands(context); + return Expression::Ptr(this); + } +} + +Expression::Ptr UserFunctionCallsite::compress(const StaticContext::Ptr &context) +{ + if(!isRecursive()) + rewrite(m_body, m_body->compress(context), context); + + return CallSite::compress(context); +} + +Expression::Properties UserFunctionCallsite::properties() const +{ + return DisableElimination; +} + +SequenceType::Ptr UserFunctionCallsite::staticType() const +{ + /* Our return type, is the static type of the function body. We could have also used + * m_functionDeclaration->signature()->returnType(), but it doesn't get updated + * when function conversion is applied. + * We can't use m_body's type if we're recursive, because m_body computes its type + * from its children, and we're at least one of the children. Hence, we would + * recurse infinitely if we did. + * + * m_body can be null here if we're called before setSource(). + */ + if(isRecursive() || !m_body) + return CommonSequenceTypes::ZeroOrMoreItems; // TODO use the declaration, it can have a type explicitly. + else + return m_body->staticType(); +} + +ExpressionVisitorResult::Ptr UserFunctionCallsite::accept(const ExpressionVisitor::Ptr &visitor) const +{ + return visitor->visit(this); +} + +Expression::ID UserFunctionCallsite::id() const +{ + return IDUserFunctionCallsite; +} + +bool UserFunctionCallsite::isSignatureValid(const FunctionSignature::Ptr &sign) const +{ + Q_ASSERT(sign); + + return sign->name() == name() + && + sign->isArityValid(m_arity); +} + +bool UserFunctionCallsite::configureRecursion(const CallTargetDescription::Ptr &sign) +{ + Q_ASSERT(sign); + + setIsRecursive(isSignatureValid(sign)); + return isRecursive(); +} + +void UserFunctionCallsite::setSource(const UserFunction::Ptr &userFunction, + const VariableSlotID cacheSlotOffset) +{ + m_functionDeclaration = userFunction; + m_body = userFunction->body(); + m_expressionSlotOffset = userFunction->expressionSlotOffset(); + + const int len = m_operands.size(); + + const VariableDeclaration::List varDecls(userFunction->argumentDeclarations()); + + for(int i = 0; i < len; ++i) + { + /* We don't want evaluation caches for range variables, it's not necessary since + * the item is already cached in DynamicContext::rangeVariable(). */ + if(m_operands.at(i)->is(IDRangeVariableReference)) + continue; + + /* Note that we pass in cacheSlotOffset + i here instead of varDecls.at(i)->slot since + * we want independent caches for each callsite. */ + m_operands[i] = Expression::Ptr(new EvaluationCache<false>(m_operands.at(i), + varDecls.at(i), + cacheSlotOffset + i)); + } +} + +FunctionSignature::Arity UserFunctionCallsite::arity() const +{ + return m_arity; +} + +CallTargetDescription::Ptr UserFunctionCallsite::callTargetDescription() const +{ + return m_functionDeclaration->signature(); +} + +QT_END_NAMESPACE |