source: trunk/src/xmlpatterns/expr/qoptimizationpasses.cpp@ 703

Last change on this file since 703 was 651, checked in by Dmitry A. Kuminov, 15 years ago

trunk: Merged in qt 4.6.2 sources.

File size: 8.5 KB
Line 
1/****************************************************************************
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3** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
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41
42#include "qcommonsequencetypes_p.h"
43#include "qoptimizerblocks_p.h"
44
45#include "qoptimizationpasses_p.h"
46
47QT_BEGIN_NAMESPACE
48
49using namespace QPatternist;
50
51OptimizationPass::List OptimizationPasses::comparisonPasses;
52OptimizationPass::List OptimizationPasses::forPasses;
53OptimizationPass::List OptimizationPasses::ifThenPasses;
54OptimizationPass::List OptimizationPasses::notFN;
55
56void OptimizationPasses::Coordinator::init()
57{
58 static bool isInitialized = false; // STATIC DATA
59
60 if(isInitialized)
61 return;
62
63 isInitialized = true;
64
65 /* Note, below is many of the building blocks re-used in several passes
66 * in order to reduce memory use. Thus, when changing one building block
67 * it potentially affects many passes. */
68
69 /* ****************************************************** */
70 /* Rewrite "count(<expr>) ge 1" into "exists(<expr>)" */
71 OptimizationPass::ExpressionMarker firstFirstChild;
72 firstFirstChild.append(0);
73 firstFirstChild.append(0);
74
75 ExpressionIdentifier::List geOpIDs;
76 const ExpressionIdentifier::Ptr countFN(new ByIDIdentifier(Expression::IDCountFN));
77 geOpIDs.append(countFN);
78 geOpIDs.append(ExpressionIdentifier::Ptr(new IntegerIdentifier(1)));
79
80 QVector<Expression::ID> geMatcher;
81 geMatcher.append(Expression::IDValueComparison);
82 geMatcher.append(Expression::IDGeneralComparison);
83
84 const ExpressionIdentifier::Ptr ge(new ComparisonIdentifier(geMatcher,
85 AtomicComparator::OperatorGreaterOrEqual));
86
87 const ExpressionCreator::Ptr existsFN(new ByIDCreator(Expression::IDExistsFN));
88 const OptimizationPass::Ptr geToExists(new OptimizationPass(ge, geOpIDs, firstFirstChild, existsFN));
89 comparisonPasses.append(geToExists);
90 /* ****************************************************** */
91
92 /* ****************************************************** */
93 /* Rewrite "count(<expr>) gt 0" into "exists(<expr>)" */
94 ExpressionIdentifier::List countAndIntZero;