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    41 

    42 #include "qcommonsequencetypes_p.h"

    43 #include "qdynamiccontextstore_p.h"

    44 #include "qevaluationcache_p.h"

    45 

    46 #include "quserfunctioncallsite_p.h"

    47 

    48 QT_BEGIN_NAMESPACE

    49 

    50 using namespace QPatternist;

    51 

    52 UserFunctionCallsite::UserFunctionCallsite(const QXmlName nameP,

    53                                            const FunctionSignature::Arity ar) : CallSite(nameP)

    54                                                                               , m_arity(ar)

    55                                                                               , m_expressionSlotOffset(-2)

    56 

    57 {

    58 }

    59 

    60 Item::Iterator::Ptr UserFunctionCallsite::evaluateSequence(const DynamicContext::Ptr &context) const

    61 {

    62     return m_body->evaluateSequence(bindVariables(context));

    63 }

    64 

    65 Item UserFunctionCallsite::evaluateSingleton(const DynamicContext::Ptr &context) const

    66 {

    67     return m_body->evaluateSingleton(bindVariables(context));

    68 }

    69 

    70 bool UserFunctionCallsite::evaluateEBV(const DynamicContext::Ptr &context) const

    71 {

    72     return m_body->evaluateEBV(bindVariables(context));

    73 }

    74 

    75 void UserFunctionCallsite::evaluateToSequenceReceiver(const DynamicContext::Ptr &context) const

    76 {

    77     m_body->evaluateToSequenceReceiver(bindVariables(context));

    78 }

    79 

    80 DynamicContext::Ptr UserFunctionCallsite::bindVariables(const DynamicContext::Ptr &context) const

    81 {

    82     const DynamicContext::Ptr stackContext(context->createStack());

    83     Q_ASSERT(stackContext);

    84 

    85     const Expression::List::const_iterator end(m_operands.constEnd());

    86     Expression::List::const_iterator it(m_operands.constBegin());

    87 

    88     VariableSlotID slot = m_expressionSlotOffset;

    89 

    90     for(; it != end; ++it)

    91     {

    92         stackContext->setExpressionVariable(slot,

    93                                             Expression::Ptr(new DynamicContextStore(*it, context)));

    94         ++slot;

    95     }

    96 

    97     return stackContext;

    98 }

    99 

   100 SequenceType::List UserFunctionCallsite::expectedOperandTypes() const

   101 {

   102     SequenceType::List result;

   103 

   104     if(m_functionDeclaration)

   105     {

   106         const FunctionArgument::List args(m_functionDeclaration->signature()->arguments());

   107         const FunctionArgument::List::const_iterator end(args.constEnd());

   108         FunctionArgument::List::const_iterator it(args.constBegin());

   109 

   110         for(; it != end; ++it)

   111             result.append((*it)->type());

   112     }

   113     else

   114         result.append(CommonSequenceTypes::ZeroOrMoreItems);

   115 

   116     return result;

   117 }

   118 

   119 Expression::Ptr UserFunctionCallsite::typeCheck(const StaticContext::Ptr &context,

   120                                                 const SequenceType::Ptr &reqType)

   121 {

   122     /* The parser calls TypeChecker::applyFunctionConversion() on user function

   123      * bodies, possibly indirectly, before all function call sites have been

   124      * resolved. Hence it's possible that we're called before before the usual

   125      * typeCheck() pass, and hence before we have been resolved/checked and

   126      * subsequently m_functionDeclaration set. Therefore, encounter for that below.

   127      *

   128      * UnresolvedVariableReference::typeCheck() has the same dilemma.

   129      */

   130 

   131     /* Ensure that the return value of the function is properly

   132      * converted/does match from where it is called(which is here). */

   133     if(isRecursive() || !m_functionDeclaration)

   134         return CallSite::typeCheck(context, reqType);

   135     else

   136     {

   137         /* Update, such that we use a recent version of the body that has typeCheck()

   138          * and compress() rewrites included. */

   139         m_body = m_functionDeclaration->body();

   140 

   141         /* Note, we can't assign to m_functionDeclaration->body() because UserFunction can apply

   142          * to several different callsites. Hence we need our own version. */

   143         m_body = m_body->typeCheck(context, reqType);

   144 

   145         /* We just act as a pipe for m_body, so we don't have to typecheck ourselves. However,

   146          * the arguments must match the function declaration. */

   147         typeCheckOperands(context);

   148         return Expression::Ptr(this);

   149     }

   150 }

   151 

   152 Expression::Ptr UserFunctionCallsite::compress(const StaticContext::Ptr &context)

   153 {

   154     if(!isRecursive())

   155         rewrite(m_body, m_body->compress(context), context);

   156 

   157     return CallSite::compress(context);

   158 }

   159 

   160 Expression::Properties UserFunctionCallsite::properties() const

   161 {

   162     return DisableElimination;

   163 }

   164 

   165 SequenceType::Ptr UserFunctionCallsite::staticType() const

   166 {

   167     /* Our return type, is the static type of the function body. We could have also used

   168      * m_functionDeclaration->signature()->returnType(), but it doesn't get updated

   169      * when function conversion is applied.

   170      * We can't use m_body's type if we're recursive, because m_body computes its type

   171      * from its children, and we're at least one of the children. Hence, we would

   172      * recurse infinitely if we did.

   173      *

   174      * m_body can be null here if we're called before setSource().

   175      */

   176     if(isRecursive() || !m_body)

   177         return CommonSequenceTypes::ZeroOrMoreItems; // TODO use the declaration, it can have a type explicitly.

   178     else

   179         return m_body->staticType();

   180 }

   181 

   182 ExpressionVisitorResult::Ptr UserFunctionCallsite::accept(const ExpressionVisitor::Ptr &visitor) const

   183 {

   184     return visitor->visit(this);

   185 }

   186 

   187 Expression::ID UserFunctionCallsite::id() const

   188 {

   189     return IDUserFunctionCallsite;

   190 }

   191 

   192 bool UserFunctionCallsite::isSignatureValid(const FunctionSignature::Ptr &sign) const

   193 {

   194     Q_ASSERT(sign);

   195 

   196     return sign->name() == name()

   197            &&

   198            sign->isArityValid(m_arity);

   199 }

   200 

   201 bool UserFunctionCallsite::configureRecursion(const CallTargetDescription::Ptr &sign)

   202 {

   203     Q_ASSERT(sign);

   204 

   205     setIsRecursive(isSignatureValid(sign));

   206     return isRecursive();

   207 }

   208 

   209 void UserFunctionCallsite::setSource(const UserFunction::Ptr &userFunction,

   210                                      const VariableSlotID cacheSlotOffset)

   211 {

   212     m_functionDeclaration = userFunction;

   213     m_body = userFunction->body();

   214     m_expressionSlotOffset = userFunction->expressionSlotOffset();

   215 

   216     const int len = m_operands.size();

   217 

   218     const VariableDeclaration::List varDecls(userFunction->argumentDeclarations());

   219 

   220     for(int i = 0; i < len; ++i)

   221     {

   222         /* We don't want evaluation caches for range variables, it's not necessary since

   223          * the item is already cached in DynamicContext::rangeVariable(). */

   224         if(m_operands.at(i)->is(IDRangeVariableReference))

   225             continue;

   226 

   227         /* Note that we pass in cacheSlotOffset + i here instead of varDecls.at(i)->slot since

   228          * we want independent caches for each callsite. */

   229         m_operands[i] = Expression::Ptr(new EvaluationCache<false>(m_operands.at(i),

   230                                                                    varDecls.at(i),

   231                                                                    cacheSlotOffset + i));

   232     }

   233 }

   234 

   235 FunctionSignature::Arity UserFunctionCallsite::arity() const

   236 {

   237     return m_arity;

   238 }

   239 

   240 CallTargetDescription::Ptr UserFunctionCallsite::callTargetDescription() const

   241 {

   242     return m_functionDeclaration->signature();

   243 }

   244 

   245 QT_END_NAMESPACE