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Branched from the monolithic repo, Qt master branch, at commit
896db169ea224deb96c59ce8af800d019de63f12

1 files changed, 182 insertions, 0 deletions

diff --git a/src/xmlpatterns/expr/qoptimizationpasses.cpp b/src/xmlpatterns/expr/qoptimizationpasses.cpp
new file mode 100644
index 0000000..d970483
--- /dev/null
+++ b/src/xmlpatterns/expr/qoptimizationpasses.cpp
@@ -0,0 +1,182 @@
+/****************************************************************************
+**
+** 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 "qoptimizerblocks_p.h"
+
+#include "qoptimizationpasses_p.h"
+
+QT_BEGIN_NAMESPACE
+
+using namespace QPatternist;
+
+OptimizationPass::List OptimizationPasses::comparisonPasses;
+OptimizationPass::List OptimizationPasses::forPasses;
+OptimizationPass::List OptimizationPasses::ifThenPasses;
+OptimizationPass::List OptimizationPasses::notFN;
+
+void OptimizationPasses::Coordinator::init()
+{
+    static bool isInitialized = false; // STATIC DATA
+
+    if(isInitialized)
+        return;
+
+    isInitialized = true;
+
+    /* Note, below is many of the building blocks re-used in several passes
+     * in order to reduce memory use. Thus, when changing one building block
+     * it potentially affects many passes. */
+
+    /* ****************************************************** */
+    /* Rewrite "count(<expr>) ge 1" into "exists(<expr>)" */
+    OptimizationPass::ExpressionMarker firstFirstChild;
+    firstFirstChild.append(0);
+    firstFirstChild.append(0);
+
+    ExpressionIdentifier::List geOpIDs;
+    const ExpressionIdentifier::Ptr countFN(new ByIDIdentifier(Expression::IDCountFN));
+    geOpIDs.append(countFN);
+    geOpIDs.append(ExpressionIdentifier::Ptr(new IntegerIdentifier(1)));
+
+    QVector<Expression::ID> geMatcher;
+    geMatcher.append(Expression::IDValueComparison);
+    geMatcher.append(Expression::IDGeneralComparison);
+
+    const ExpressionIdentifier::Ptr ge(new ComparisonIdentifier(geMatcher,
+                                                                AtomicComparator::OperatorGreaterOrEqual));
+
+    const ExpressionCreator::Ptr existsFN(new ByIDCreator(Expression::IDExistsFN));
+    const OptimizationPass::Ptr geToExists(new OptimizationPass(ge, geOpIDs, firstFirstChild, existsFN));
+    comparisonPasses.append(geToExists);
+    /* ****************************************************** */
+
+    /* ****************************************************** */
+    /* Rewrite "count(<expr>) gt 0" into "exists(<expr>)" */
+    ExpressionIdentifier::List countAndIntZero;
+    countAndIntZero.append(countFN);
+    const ExpressionIdentifier::Ptr zeroInteger(new IntegerIdentifier(0));
+    countAndIntZero.append(zeroInteger);
+
+    const ExpressionIdentifier::Ptr gt(new ComparisonIdentifier(geMatcher,
+                                                                AtomicComparator::OperatorGreaterThan));
+
+    const OptimizationPass::Ptr gtToExists(new OptimizationPass(gt, countAndIntZero,
+                                                                firstFirstChild, existsFN));
+    comparisonPasses.append(gtToExists);
+    /* ****************************************************** */
+
+    /* ****************************************************** */
+    /* Rewrite "count(<expr>) ne 0" into "exists(<expr>)" */
+
+    const ExpressionIdentifier::Ptr ne(new ComparisonIdentifier(geMatcher,
+                                                                AtomicComparator::OperatorNotEqual));
+    const OptimizationPass::Ptr neToExists(new OptimizationPass(ne, countAndIntZero, firstFirstChild,
+                                                                existsFN,
+                                                                OptimizationPass::AnyOrder));
+    comparisonPasses.append(neToExists);
+    /* ****************************************************** */
+
+    /* ****************************************************** */
+    /* Rewrite "count(<expr>) eq 0" into "empty(<expr>)" */
+    ExpressionIdentifier::List eqOpIDs;
+    eqOpIDs.append(countFN);
+    eqOpIDs.append(zeroInteger);
+    const ExpressionCreator::Ptr emptyFN(new ByIDCreator(Expression::IDEmptyFN));
+    const ExpressionIdentifier::Ptr eq(new ComparisonIdentifier(geMatcher,
+                                                                AtomicComparator::OperatorEqual));
+    const OptimizationPass::Ptr eqToEmpty(new OptimizationPass(eq, eqOpIDs, firstFirstChild,
+                                                               emptyFN,
+                                                               OptimizationPass::AnyOrder));
+    comparisonPasses.append(eqToEmpty);
+
+    /* ****************************************************** */
+
+    /* ****************************************************** */
+    /* Rewrite "for $var in <expr> return $var" into "<expr>" */
+    ExpressionIdentifier::List forOps;
+    OptimizationPass::ExpressionMarker firstChild;
+    firstChild.append(0);
+
+    forOps.append(ExpressionIdentifier::Ptr());
+    forOps.append(ExpressionIdentifier::Ptr(new ByIDIdentifier(Expression::IDRangeVariableReference)));
+    const OptimizationPass::Ptr simplifyFor(new OptimizationPass(ExpressionIdentifier::Ptr(), forOps,
+                                                                 firstChild, ExpressionCreator::Ptr()));
+    forPasses.append(simplifyFor);
+    /* ****************************************************** */
+
+    /* ****************************************************** */
+    /* Rewrite "if(<expr>) then true() else false()" to "<expr>" */
+    OptimizationPass::ExpressionMarker marker;
+    marker.append(0);
+
+    ExpressionIdentifier::List opIDs;
+    opIDs.append(ExpressionIdentifier::Ptr(new BySequenceTypeIdentifier(
+                        CommonSequenceTypes::ExactlyOneBoolean)));
+    opIDs.append(ExpressionIdentifier::Ptr(new BooleanIdentifier(true)));
+    opIDs.append(ExpressionIdentifier::Ptr(new BooleanIdentifier(false)));
+
+    const OptimizationPass::Ptr pass(new OptimizationPass(ExpressionIdentifier::Ptr(), opIDs, marker));
+    ifThenPasses.append(pass);
+    /* ****************************************************** */
+
+    /* ****************************************************** */
+    /* Rewrite "not(exists(X))" into "empty(X)" */
+    ExpressionIdentifier::List idExistsFN;
+    idExistsFN.append(ExpressionIdentifier::Ptr(new ByIDIdentifier(Expression::IDExistsFN)));
+
+    notFN.append(OptimizationPass::Ptr(new OptimizationPass(ExpressionIdentifier::Ptr(),
+                                                            idExistsFN,
+                                                            firstFirstChild,
+                                                            emptyFN)));
+
+    /* Rewrite "not(empty(X))" into "exists(X)" */
+    ExpressionIdentifier::List idEmptyFN;
+    idEmptyFN.append(ExpressionIdentifier::Ptr(new ByIDIdentifier(Expression::IDEmptyFN)));
+
+    notFN.append(OptimizationPass::Ptr(new OptimizationPass(ExpressionIdentifier::Ptr(),
+                                                            idEmptyFN,
+                                                            firstFirstChild,
+                                                            existsFN)));
+    /* ****************************************************** */
+}
+
+QT_END_NAMESPACE