Check in the pristine copy of ICU 4.6...

icu46/source/common/rbbitblb.cpp

+/*
+**********************************************************************
+*   Copyright (c) 2002-2009, International Business Machines
+*   Corporation and others.  All Rights Reserved.
+**********************************************************************
+*/
+//
+//  rbbitblb.cpp
+//
+
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_BREAK_ITERATION
+
+#include "unicode/unistr.h"
+#include "rbbitblb.h"
+#include "rbbirb.h"
+#include "rbbisetb.h"
+#include "rbbidata.h"
+#include "cstring.h"
+#include "uassert.h"
+#include "cmemory.h"
+
+U_NAMESPACE_BEGIN
+
+RBBITableBuilder::RBBITableBuilder(RBBIRuleBuilder *rb, RBBINode **rootNode) :
+ fTree(*rootNode) {
+    fRB                 = rb;
+    fStatus             = fRB->fStatus;
+    UErrorCode status   = U_ZERO_ERROR;
+    fDStates            = new UVector(status);
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    if (U_FAILURE(status)) {
+        *fStatus = status;
+        return;
+    }
+    if (fDStates == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;;
+    }
+}
+
+
+
+RBBITableBuilder::~RBBITableBuilder() {
+    int i;
+    for (i=0; i<fDStates->size(); i++) {
+        delete (RBBIStateDescriptor *)fDStates->elementAt(i);
+    }
+    delete   fDStates;
+}
+
+
+//-----------------------------------------------------------------------------
+//
+//   RBBITableBuilder::build  -  This is the main function for building the DFA state transtion
+//                               table from the RBBI rules parse tree.
+//
+//-----------------------------------------------------------------------------
+void  RBBITableBuilder::build() {
+
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+
+    // If there were no rules, just return.  This situation can easily arise
+    //   for the reverse rules.
+    if (fTree==NULL) {
+        return;
+    }
+
+    //
+    // Walk through the tree, replacing any references to $variables with a copy of the
+    //   parse tree for the substition expression.
+    //
+    fTree = fTree->flattenVariables();
+#ifdef RBBI_DEBUG
+    if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "ftree")) {
+        RBBIDebugPuts("Parse tree after flattening variable references.");
+        fTree->printTree(TRUE);
+    }
+#endif
+
+    //
+    // If the rules contained any references to {bof} 
+    //   add a {bof} <cat> <former root of tree> to the
+    //   tree.  Means that all matches must start out with the 
+    //   {bof} fake character.
+    // 
+    if (fRB->fSetBuilder->sawBOF()) {
+        RBBINode *bofTop    = new RBBINode(RBBINode::opCat);
+        RBBINode *bofLeaf   = new RBBINode(RBBINode::leafChar);
+        // Delete and exit if memory allocation failed.
+        if (bofTop == NULL || bofLeaf == NULL) {
+            *fStatus = U_MEMORY_ALLOCATION_ERROR;
+            delete bofTop;
+            delete bofLeaf;
+            return;
+        }
+        bofTop->fLeftChild  = bofLeaf;
+        bofTop->fRightChild = fTree;
+        bofLeaf->fParent    = bofTop;
+        bofLeaf->fVal       = 2;      // Reserved value for {bof}.
+        fTree               = bofTop;
+    }
+
+    //
+    // Add a unique right-end marker to the expression.
+    //   Appears as a cat-node, left child being the original tree,
+    //   right child being the end marker.
+    //
+    RBBINode *cn = new RBBINode(RBBINode::opCat);
+    // Exit if memory allocation failed.
+    if (cn == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+        return;
+    }
+    cn->fLeftChild = fTree;
+    fTree->fParent = cn;
+    cn->fRightChild = new RBBINode(RBBINode::endMark);
+    // Delete and exit if memory allocation failed.
+    if (cn->fRightChild == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+        delete cn;
+        return;
+    }
+    cn->fRightChild->fParent = cn;
+    fTree = cn;
+
+    //
+    //  Replace all references to UnicodeSets with the tree for the equivalent
+    //      expression.
+    //
+    fTree->flattenSets();
+#ifdef RBBI_DEBUG
+    if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "stree")) {
+        RBBIDebugPuts("Parse tree after flattening Unicode Set references.");
+        fTree->printTree(TRUE);
+    }
+#endif
+
+
+    //
+    // calculate the functions nullable, firstpos, lastpos and followpos on
+    // nodes in the parse tree.
+    //    See the alogrithm description in Aho.
+    //    Understanding how this works by looking at the code alone will be
+    //       nearly impossible.
+    //
+    calcNullable(fTree);
+    calcFirstPos(fTree);
+    calcLastPos(fTree);
+    calcFollowPos(fTree);
+    if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "pos")) {
+        RBBIDebugPuts("\n");
+        printPosSets(fTree);
+    }
+
+    //
+    //  For "chained" rules, modify the followPos sets
+    //
+    if (fRB->fChainRules) {
+        calcChainedFollowPos(fTree);
+    }
+
+    //
+    //  BOF (start of input) test fixup.
+    //
+    if (fRB->fSetBuilder->sawBOF()) {
+        bofFixup();
+    }
+
+    //
+    // Build the DFA state transition tables.
+    //
+    buildStateTable();
+    flagAcceptingStates();
+    flagLookAheadStates();
+    flagTaggedStates();
+
+    //
+    // Update the global table of rule status {tag} values
+    // The rule builder has a global vector of status values that are common
+    //    for all tables.  Merge the ones from this table into the global set.
+    //
+    mergeRuleStatusVals();
+
+    if (fRB->fDebugEnv && uprv_strstr(fRB->fDebugEnv, "states")) {printStates();};
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   calcNullable.    Impossible to explain succinctly.  See Aho, section 3.9
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::calcNullable(RBBINode *n) {
+    if (n == NULL) {
+        return;
+    }
+    if (n->fType == RBBINode::setRef ||
+        n->fType == RBBINode::endMark ) {
+        // These are non-empty leaf node types.
+        n->fNullable = FALSE;
+        return;
+    }
+
+    if (n->fType == RBBINode::lookAhead || n->fType == RBBINode::tag) {
+        // Lookahead marker node.  It's a leaf, so no recursion on children.
+        // It's nullable because it does not match any literal text from the input stream.
+        n->fNullable = TRUE;
+        return;
+    }
+
+
+    // The node is not a leaf.
+    //  Calculate nullable on its children.
+    calcNullable(n->fLeftChild);
+    calcNullable(n->fRightChild);
+
+    // Apply functions from table 3.40 in Aho
+    if (n->fType == RBBINode::opOr) {
+        n->fNullable = n->fLeftChild->fNullable || n->fRightChild->fNullable;
+    }
+    else if (n->fType == RBBINode::opCat) {
+        n->fNullable = n->fLeftChild->fNullable && n->fRightChild->fNullable;
+    }
+    else if (n->fType == RBBINode::opStar || n->fType == RBBINode::opQuestion) {
+        n->fNullable = TRUE;
+    }
+    else {
+        n->fNullable = FALSE;
+    }
+}
+
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   calcFirstPos.    Impossible to explain succinctly.  See Aho, section 3.9
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::calcFirstPos(RBBINode *n) {
+    if (n == NULL) {
+        return;
+    }
+    if (n->fType == RBBINode::leafChar  ||
+        n->fType == RBBINode::endMark   ||
+        n->fType == RBBINode::lookAhead ||
+        n->fType == RBBINode::tag) {
+        // These are non-empty leaf node types.
+        // Note: In order to maintain the sort invariant on the set,
+        // this function should only be called on a node whose set is
+        // empty to start with.
+        n->fFirstPosSet->addElement(n, *fStatus);
+        return;
+    }
+
+    // The node is not a leaf.
+    //  Calculate firstPos on its children.
+    calcFirstPos(n->fLeftChild);
+    calcFirstPos(n->fRightChild);
+
+    // Apply functions from table 3.40 in Aho
+    if (n->fType == RBBINode::opOr) {
+        setAdd(n->fFirstPosSet, n->fLeftChild->fFirstPosSet);
+        setAdd(n->fFirstPosSet, n->fRightChild->fFirstPosSet);
+    }
+    else if (n->fType == RBBINode::opCat) {
+        setAdd(n->fFirstPosSet, n->fLeftChild->fFirstPosSet);
+        if (n->fLeftChild->fNullable) {
+            setAdd(n->fFirstPosSet, n->fRightChild->fFirstPosSet);
+        }
+    }
+    else if (n->fType == RBBINode::opStar ||
+             n->fType == RBBINode::opQuestion ||
+             n->fType == RBBINode::opPlus) {
+        setAdd(n->fFirstPosSet, n->fLeftChild->fFirstPosSet);
+    }
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   calcLastPos.    Impossible to explain succinctly.  See Aho, section 3.9
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::calcLastPos(RBBINode *n) {
+    if (n == NULL) {
+        return;
+    }
+    if (n->fType == RBBINode::leafChar  ||
+        n->fType == RBBINode::endMark   ||
+        n->fType == RBBINode::lookAhead ||
+        n->fType == RBBINode::tag) {
+        // These are non-empty leaf node types.
+        // Note: In order to maintain the sort invariant on the set,
+        // this function should only be called on a node whose set is
+        // empty to start with.
+        n->fLastPosSet->addElement(n, *fStatus);
+        return;
+    }
+
+    // The node is not a leaf.
+    //  Calculate lastPos on its children.
+    calcLastPos(n->fLeftChild);
+    calcLastPos(n->fRightChild);
+
+    // Apply functions from table 3.40 in Aho
+    if (n->fType == RBBINode::opOr) {
+        setAdd(n->fLastPosSet, n->fLeftChild->fLastPosSet);
+        setAdd(n->fLastPosSet, n->fRightChild->fLastPosSet);
+    }
+    else if (n->fType == RBBINode::opCat) {
+        setAdd(n->fLastPosSet, n->fRightChild->fLastPosSet);
+        if (n->fRightChild->fNullable) {
+            setAdd(n->fLastPosSet, n->fLeftChild->fLastPosSet);
+        }
+    }
+    else if (n->fType == RBBINode::opStar     ||
+             n->fType == RBBINode::opQuestion ||
+             n->fType == RBBINode::opPlus) {
+        setAdd(n->fLastPosSet, n->fLeftChild->fLastPosSet);
+    }
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   calcFollowPos.    Impossible to explain succinctly.  See Aho, section 3.9
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::calcFollowPos(RBBINode *n) {
+    if (n == NULL ||
+        n->fType == RBBINode::leafChar ||
+        n->fType == RBBINode::endMark) {
+        return;
+    }
+
+    calcFollowPos(n->fLeftChild);
+    calcFollowPos(n->fRightChild);
+
+    // Aho rule #1
+    if (n->fType == RBBINode::opCat) {
+        RBBINode *i;   // is 'i' in Aho's description
+        uint32_t     ix;
+
+        UVector *LastPosOfLeftChild = n->fLeftChild->fLastPosSet;
+
+        for (ix=0; ix<(uint32_t)LastPosOfLeftChild->size(); ix++) {
+            i = (RBBINode *)LastPosOfLeftChild->elementAt(ix);
+            setAdd(i->fFollowPos, n->fRightChild->fFirstPosSet);
+        }
+    }
+
+    // Aho rule #2
+    if (n->fType == RBBINode::opStar ||
+        n->fType == RBBINode::opPlus) {
+        RBBINode   *i;  // again, n and i are the names from Aho's description.
+        uint32_t    ix;
+
+        for (ix=0; ix<(uint32_t)n->fLastPosSet->size(); ix++) {
+            i = (RBBINode *)n->fLastPosSet->elementAt(ix);
+            setAdd(i->fFollowPos, n->fFirstPosSet);
+        }
+    }
+
+
+
+}
+
+
+//-----------------------------------------------------------------------------
+//
+//   calcChainedFollowPos.    Modify the previously calculated followPos sets
+//                            to implement rule chaining.  NOT described by Aho
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::calcChainedFollowPos(RBBINode *tree) {
+
+    UVector         endMarkerNodes(*fStatus);
+    UVector         leafNodes(*fStatus);
+    int32_t         i;
+
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+
+    // get a list of all endmarker nodes.
+    tree->findNodes(&endMarkerNodes, RBBINode::endMark, *fStatus);
+
+    // get a list all leaf nodes
+    tree->findNodes(&leafNodes, RBBINode::leafChar, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+
+    // Get all nodes that can be the start a match, which is FirstPosition()
+    // of the portion of the tree corresponding to user-written rules.
+    // See the tree description in bofFixup().
+    RBBINode *userRuleRoot = tree;
+    if (fRB->fSetBuilder->sawBOF()) {
+        userRuleRoot = tree->fLeftChild->fRightChild;
+    }
+    U_ASSERT(userRuleRoot != NULL);
+    UVector *matchStartNodes = userRuleRoot->fFirstPosSet;
+
+
+    // Iteratate over all leaf nodes,
+    //
+    int32_t  endNodeIx;
+    int32_t  startNodeIx;
+
+    for (endNodeIx=0; endNodeIx<leafNodes.size(); endNodeIx++) {
+        RBBINode *tNode   = (RBBINode *)leafNodes.elementAt(endNodeIx);
+        RBBINode *endNode = NULL;
+
+        // Identify leaf nodes that correspond to overall rule match positions.
+        //   These include an endMarkerNode in their followPos sets.
+        for (i=0; i<endMarkerNodes.size(); i++) {
+            if (tNode->fFollowPos->contains(endMarkerNodes.elementAt(i))) {
+                endNode = tNode;
+                break;
+            }
+        }
+        if (endNode == NULL) {
+            // node wasn't an end node.  Try again with the next.
+            continue;
+        }
+
+        // We've got a node that can end a match.
+
+        // Line Break Specific hack:  If this node's val correspond to the $CM char class,
+        //                            don't chain from it.
+        // TODO:  Add rule syntax for this behavior, get specifics out of here and
+        //        into the rule file.
+        if (fRB->fLBCMNoChain) {
+            UChar32 c = this->fRB->fSetBuilder->getFirstChar(endNode->fVal);
+            if (c != -1) {
+                // c == -1 occurs with sets containing only the {eof} marker string.
+                ULineBreak cLBProp = (ULineBreak)u_getIntPropertyValue(c, UCHAR_LINE_BREAK);
+                if (cLBProp == U_LB_COMBINING_MARK) {
+                    continue;
+                }
+            }
+        }
+
+
+        // Now iterate over the nodes that can start a match, looking for ones
+        //   with the same char class as our ending node.
+        RBBINode *startNode;
+        for (startNodeIx = 0; startNodeIx<matchStartNodes->size(); startNodeIx++) {
+            startNode = (RBBINode *)matchStartNodes->elementAt(startNodeIx);
+            if (startNode->fType != RBBINode::leafChar) {
+                continue;
+            }
+
+            if (endNode->fVal == startNode->fVal) {
+                // The end val (character class) of one possible match is the
+                //   same as the start of another.
+
+                // Add all nodes from the followPos of the start node to the
+                //  followPos set of the end node, which will have the effect of
+                //  letting matches transition from a match state at endNode
+                //  to the second char of a match starting with startNode.
+                setAdd(endNode->fFollowPos, startNode->fFollowPos);
+            }
+        }
+    }
+}
+
+
+//-----------------------------------------------------------------------------
+//
+//   bofFixup.    Fixup for state tables that include {bof} beginning of input testing.
+//                Do an swizzle similar to chaining, modifying the followPos set of
+//                the bofNode to include the followPos nodes from other {bot} nodes
+//                scattered through the tree.
+//
+//                This function has much in common with calcChainedFollowPos().
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::bofFixup() {
+
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+
+    //   The parse tree looks like this ...
+    //         fTree root  --->       <cat>
+    //                               /     \       .
+    //                            <cat>   <#end node>
+    //                           /     \  .
+    //                     <bofNode>   rest
+    //                               of tree
+    //
+    //    We will be adding things to the followPos set of the <bofNode>
+    //
+    RBBINode  *bofNode = fTree->fLeftChild->fLeftChild;
+    U_ASSERT(bofNode->fType == RBBINode::leafChar);
+    U_ASSERT(bofNode->fVal == 2);
+
+    // Get all nodes that can be the start a match of the user-written rules
+    //  (excluding the fake bofNode)
+    //  We want the nodes that can start a match in the
+    //     part labeled "rest of tree"
+    // 
+    UVector *matchStartNodes = fTree->fLeftChild->fRightChild->fFirstPosSet;
+
+    RBBINode *startNode;
+    int       startNodeIx;
+    for (startNodeIx = 0; startNodeIx<matchStartNodes->size(); startNodeIx++) {
+        startNode = (RBBINode *)matchStartNodes->elementAt(startNodeIx);
+        if (startNode->fType != RBBINode::leafChar) {
+            continue;
+        }
+
+        if (startNode->fVal == bofNode->fVal) {
+            //  We found a leaf node corresponding to a {bof} that was
+            //    explicitly written into a rule.
+            //  Add everything from the followPos set of this node to the
+            //    followPos set of the fake bofNode at the start of the tree.
+            //  
+            setAdd(bofNode->fFollowPos, startNode->fFollowPos);
+        }
+    }
+}
+
+//-----------------------------------------------------------------------------
+//
+//   buildStateTable()    Determine the set of runtime DFA states and the
+//                        transition tables for these states, by the algorithm
+//                        of fig. 3.44 in Aho.
+//
+//                        Most of the comments are quotes of Aho's psuedo-code.
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::buildStateTable() {
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    RBBIStateDescriptor *failState;
+    // Set it to NULL to avoid uninitialized warning
+    RBBIStateDescriptor *initialState = NULL; 
+    //
+    // Add a dummy state 0 - the stop state.  Not from Aho.
+    int      lastInputSymbol = fRB->fSetBuilder->getNumCharCategories() - 1;
+    failState = new RBBIStateDescriptor(lastInputSymbol, fStatus);
+    if (failState == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+        goto ExitBuildSTdeleteall;
+    }
+    failState->fPositions = new UVector(*fStatus);
+    if (failState->fPositions == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+    }
+    if (failState->fPositions == NULL || U_FAILURE(*fStatus)) {
+        goto ExitBuildSTdeleteall;
+    }
+    fDStates->addElement(failState, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        goto ExitBuildSTdeleteall;
+    }
+
+    // initially, the only unmarked state in Dstates is firstpos(root),
+    //       where toot is the root of the syntax tree for (r)#;
+    initialState = new RBBIStateDescriptor(lastInputSymbol, fStatus);
+    if (initialState == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+    }
+    if (U_FAILURE(*fStatus)) {
+        goto ExitBuildSTdeleteall;
+    }
+    initialState->fPositions = new UVector(*fStatus);
+    if (initialState->fPositions == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+    }
+    if (U_FAILURE(*fStatus)) {
+        goto ExitBuildSTdeleteall;
+    }
+    setAdd(initialState->fPositions, fTree->fFirstPosSet);
+    fDStates->addElement(initialState, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        goto ExitBuildSTdeleteall;
+    }
+
+    // while there is an unmarked state T in Dstates do begin
+    for (;;) {
+        RBBIStateDescriptor *T = NULL;
+        int32_t              tx;
+        for (tx=1; tx<fDStates->size(); tx++) {
+            RBBIStateDescriptor *temp;
+            temp = (RBBIStateDescriptor *)fDStates->elementAt(tx);
+            if (temp->fMarked == FALSE) {
+                T = temp;
+                break;
+            }
+        }
+        if (T == NULL) {
+            break;
+        }
+
+        // mark T;
+        T->fMarked = TRUE;
+
+        // for each input symbol a do begin
+        int32_t  a;
+        for (a = 1; a<=lastInputSymbol; a++) {
+            // let U be the set of positions that are in followpos(p)
+            //    for some position p in T
+            //    such that the symbol at position p is a;
+            UVector    *U = NULL;
+            RBBINode   *p;
+            int32_t     px;
+            for (px=0; px<T->fPositions->size(); px++) {
+                p = (RBBINode *)T->fPositions->elementAt(px);
+                if ((p->fType == RBBINode::leafChar) &&  (p->fVal == a)) {
+                    if (U == NULL) {
+                        U = new UVector(*fStatus);
+                        if (U == NULL) {
+                                *fStatus = U_MEMORY_ALLOCATION_ERROR;
+                                goto ExitBuildSTdeleteall;
+                        }
+                    }
+                    setAdd(U, p->fFollowPos);
+                }
+            }
+
+            // if U is not empty and not in DStates then
+            int32_t  ux = 0;
+            UBool    UinDstates = FALSE;
+            if (U != NULL) {
+                U_ASSERT(U->size() > 0);
+                int  ix;
+                for (ix=0; ix<fDStates->size(); ix++) {
+                    RBBIStateDescriptor *temp2;
+                    temp2 = (RBBIStateDescriptor *)fDStates->elementAt(ix);
+                    if (setEquals(U, temp2->fPositions)) {
+                        delete U;
+                        U  = temp2->fPositions;
+                        ux = ix;
+                        UinDstates = TRUE;
+                        break;
+                    }
+                }
+
+                // Add U as an unmarked state to Dstates
+                if (!UinDstates)
+                {
+                    RBBIStateDescriptor *newState = new RBBIStateDescriptor(lastInputSymbol, fStatus);
+                    if (newState == NULL) {
+                        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+                    }
+                    if (U_FAILURE(*fStatus)) {
+                        goto ExitBuildSTdeleteall;
+                    }
+                    newState->fPositions = U;
+                    fDStates->addElement(newState, *fStatus);
+                    if (U_FAILURE(*fStatus)) {
+                        return;
+                    }
+                    ux = fDStates->size()-1;
+                }
+
+                // Dtran[T, a] := U;
+                T->fDtran->setElementAt(ux, a);
+            }
+        }
+    }
+    return;
+    // delete local pointers only if error occured.
+ExitBuildSTdeleteall:
+    delete initialState;
+    delete failState;
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   flagAcceptingStates    Identify accepting states.
+//                          First get a list of all of the end marker nodes.
+//                          Then, for each state s,
+//                              if s contains one of the end marker nodes in its list of tree positions then
+//                                  s is an accepting state.
+//
+//-----------------------------------------------------------------------------
+void     RBBITableBuilder::flagAcceptingStates() {
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    UVector     endMarkerNodes(*fStatus);
+    RBBINode    *endMarker;
+    int32_t     i;
+    int32_t     n;
+
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+
+    fTree->findNodes(&endMarkerNodes, RBBINode::endMark, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+
+    for (i=0; i<endMarkerNodes.size(); i++) {
+        endMarker = (RBBINode *)endMarkerNodes.elementAt(i);
+        for (n=0; n<fDStates->size(); n++) {
+            RBBIStateDescriptor *sd = (RBBIStateDescriptor *)fDStates->elementAt(n);
+            if (sd->fPositions->indexOf(endMarker) >= 0) {
+                // Any non-zero value for fAccepting means this is an accepting node.
+                // The value is what will be returned to the user as the break status.
+                // If no other value was specified, force it to -1.
+
+                if (sd->fAccepting==0) {
+                    // State hasn't been marked as accepting yet.  Do it now.
+                    sd->fAccepting = endMarker->fVal;
+                    if (sd->fAccepting == 0) {
+                        sd->fAccepting = -1;
+                    }
+                }
+                if (sd->fAccepting==-1 && endMarker->fVal != 0) {
+                    // Both lookahead and non-lookahead accepting for this state.
+                    // Favor the look-ahead.  Expedient for line break.
+                    // TODO:  need a more elegant resolution for conflicting rules.
+                    sd->fAccepting = endMarker->fVal;
+                }
+                // implicit else:
+                // if sd->fAccepting already had a value other than 0 or -1, leave it be.
+
+                // If the end marker node is from a look-ahead rule, set
+                //   the fLookAhead field or this state also.
+                if (endMarker->fLookAheadEnd) {
+                    // TODO:  don't change value if already set?
+                    // TODO:  allow for more than one active look-ahead rule in engine.
+                    //        Make value here an index to a side array in engine?
+                    sd->fLookAhead = sd->fAccepting;
+                }
+            }
+        }
+    }
+}
+
+
+//-----------------------------------------------------------------------------
+//
+//    flagLookAheadStates   Very similar to flagAcceptingStates, above.
+//
+//-----------------------------------------------------------------------------
+void     RBBITableBuilder::flagLookAheadStates() {
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    UVector     lookAheadNodes(*fStatus);
+    RBBINode    *lookAheadNode;
+    int32_t     i;
+    int32_t     n;
+
+    fTree->findNodes(&lookAheadNodes, RBBINode::lookAhead, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    for (i=0; i<lookAheadNodes.size(); i++) {
+        lookAheadNode = (RBBINode *)lookAheadNodes.elementAt(i);
+
+        for (n=0; n<fDStates->size(); n++) {
+            RBBIStateDescriptor *sd = (RBBIStateDescriptor *)fDStates->elementAt(n);
+            if (sd->fPositions->indexOf(lookAheadNode) >= 0) {
+                sd->fLookAhead = lookAheadNode->fVal;
+            }
+        }
+    }
+}
+
+
+
+
+//-----------------------------------------------------------------------------
+//
+//    flagTaggedStates
+//
+//-----------------------------------------------------------------------------
+void     RBBITableBuilder::flagTaggedStates() {
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    UVector     tagNodes(*fStatus);
+    RBBINode    *tagNode;
+    int32_t     i;
+    int32_t     n;
+
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    fTree->findNodes(&tagNodes, RBBINode::tag, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    for (i=0; i<tagNodes.size(); i++) {                   // For each tag node t (all of 'em)
+        tagNode = (RBBINode *)tagNodes.elementAt(i);
+
+        for (n=0; n<fDStates->size(); n++) {              //    For each state  s (row in the state table)
+            RBBIStateDescriptor *sd = (RBBIStateDescriptor *)fDStates->elementAt(n);
+            if (sd->fPositions->indexOf(tagNode) >= 0) {  //       if  s include the tag node t
+                sortedAdd(&sd->fTagVals, tagNode->fVal);
+            }
+        }
+    }
+}
+
+
+
+
+//-----------------------------------------------------------------------------
+//
+//  mergeRuleStatusVals
+//
+//      Update the global table of rule status {tag} values
+//      The rule builder has a global vector of status values that are common
+//      for all tables.  Merge the ones from this table into the global set.
+//
+//-----------------------------------------------------------------------------
+void  RBBITableBuilder::mergeRuleStatusVals() {
+    //
+    //  The basic outline of what happens here is this...
+    //
+    //    for each state in this state table
+    //       if the status tag list for this state is in the global statuses list
+    //           record where and
+    //           continue with the next state
+    //       else
+    //           add the tag list for this state to the global list.
+    //
+    int i;
+    int n;
+
+    // Pre-set a single tag of {0} into the table.
+    //   We will need this as a default, for rule sets with no explicit tagging.
+    if (fRB->fRuleStatusVals->size() == 0) {
+        fRB->fRuleStatusVals->addElement(1, *fStatus);  // Num of statuses in group
+        fRB->fRuleStatusVals->addElement((int32_t)0, *fStatus);  //   and our single status of zero
+    }
+
+    //    For each state
+    for (n=0; n<fDStates->size(); n++) {
+        RBBIStateDescriptor *sd = (RBBIStateDescriptor *)fDStates->elementAt(n);
+        UVector *thisStatesTagValues = sd->fTagVals;
+        if (thisStatesTagValues == NULL) {
+            // No tag values are explicitly associated with this state.
+            //   Set the default tag value.
+            sd->fTagsIdx = 0;
+            continue;
+        }
+
+        // There are tag(s) associated with this state.
+        //   fTagsIdx will be the index into the global tag list for this state's tag values.
+        //   Initial value of -1 flags that we haven't got it set yet.
+        sd->fTagsIdx = -1;
+        int32_t  thisTagGroupStart = 0;   // indexes into the global rule status vals list
+        int32_t  nextTagGroupStart = 0;
+
+        // Loop runs once per group of tags in the global list
+        while (nextTagGroupStart < fRB->fRuleStatusVals->size()) {
+            thisTagGroupStart = nextTagGroupStart;
+            nextTagGroupStart += fRB->fRuleStatusVals->elementAti(thisTagGroupStart) + 1;
+            if (thisStatesTagValues->size() != fRB->fRuleStatusVals->elementAti(thisTagGroupStart)) {
+                // The number of tags for this state is different from
+                //    the number of tags in this group from the global list.
+                //    Continue with the next group from the global list.
+                continue;
+            }
+            // The lengths match, go ahead and compare the actual tag values
+            //    between this state and the group from the global list.
+            for (i=0; i<thisStatesTagValues->size(); i++) {
+                if (thisStatesTagValues->elementAti(i) !=
+                    fRB->fRuleStatusVals->elementAti(thisTagGroupStart + 1 + i) ) {
+                    // Mismatch.
+                    break;
+                }
+            }
+
+            if (i == thisStatesTagValues->size()) {
+                // We found a set of tag values in the global list that match
+                //   those for this state.  Use them.
+                sd->fTagsIdx = thisTagGroupStart;
+                break;
+            }
+        }
+
+        if (sd->fTagsIdx == -1) {
+            // No suitable entry in the global tag list already.  Add one
+            sd->fTagsIdx = fRB->fRuleStatusVals->size();
+            fRB->fRuleStatusVals->addElement(thisStatesTagValues->size(), *fStatus);
+            for (i=0; i<thisStatesTagValues->size(); i++) {
+                fRB->fRuleStatusVals->addElement(thisStatesTagValues->elementAti(i), *fStatus);
+            }
+        }
+    }
+}
+
+
+
+
+
+
+
+//-----------------------------------------------------------------------------
+//
+//  sortedAdd  Add a value to a vector of sorted values (ints).
+//             Do not replicate entries; if the value is already there, do not
+//                add a second one.
+//             Lazily create the vector if it does not already exist.
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::sortedAdd(UVector **vector, int32_t val) {
+    int32_t i;
+
+    if (*vector == NULL) {
+        *vector = new UVector(*fStatus);
+    }
+    if (*vector == NULL || U_FAILURE(*fStatus)) {
+        return;
+    }
+    UVector *vec = *vector;
+    int32_t  vSize = vec->size();
+    for (i=0; i<vSize; i++) {
+        int32_t valAtI = vec->elementAti(i);
+        if (valAtI == val) {
+            // The value is already in the vector.  Don't add it again.
+            return;
+        }
+        if (valAtI > val) {
+            break;
+        }
+    }
+    vec->insertElementAt(val, i, *fStatus);
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//  setAdd     Set operation on UVector
+//             dest = dest union source
+//             Elements may only appear once and must be sorted.
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::setAdd(UVector *dest, UVector *source) {
+    int32_t destOriginalSize = dest->size();
+    int32_t sourceSize       = source->size();
+    int32_t di           = 0;
+    MaybeStackArray<void *, 16> destArray, sourceArray;  // Handle small cases without malloc
+    void **destPtr, **sourcePtr;
+    void **destLim, **sourceLim;
+
+    if (destOriginalSize > destArray.getCapacity()) {
+        if (destArray.resize(destOriginalSize) == NULL) {
+            return;
+        }
+    }
+    destPtr = destArray.getAlias();
+    destLim = destPtr + destOriginalSize;  // destArray.getArrayLimit()?
+
+    if (sourceSize > sourceArray.getCapacity()) {
+        if (sourceArray.resize(sourceSize) == NULL) {
+            return;
+        }
+    }
+    sourcePtr = sourceArray.getAlias();
+    sourceLim = sourcePtr + sourceSize;  // sourceArray.getArrayLimit()?
+
+    // Avoid multiple "get element" calls by getting the contents into arrays
+    (void) dest->toArray(destPtr);
+    (void) source->toArray(sourcePtr);
+
+    dest->setSize(sourceSize+destOriginalSize, *fStatus);
+
+    while (sourcePtr < sourceLim && destPtr < destLim) {
+        if (*destPtr == *sourcePtr) {
+            dest->setElementAt(*sourcePtr++, di++);
+            destPtr++;
+        }
+        // This check is required for machines with segmented memory, like i5/OS.
+        // Direct pointer comparison is not recommended.
+        else if (uprv_memcmp(destPtr, sourcePtr, sizeof(void *)) < 0) {
+            dest->setElementAt(*destPtr++, di++);
+        }
+        else { /* *sourcePtr < *destPtr */
+            dest->setElementAt(*sourcePtr++, di++);
+        }
+    }
+
+    // At most one of these two cleanup loops will execute
+    while (destPtr < destLim) {
+        dest->setElementAt(*destPtr++, di++);
+    }
+    while (sourcePtr < sourceLim) {
+        dest->setElementAt(*sourcePtr++, di++);
+    }
+
+    dest->setSize(di, *fStatus);
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//  setEqual    Set operation on UVector.
+//              Compare for equality.
+//              Elements must be sorted.
+//
+//-----------------------------------------------------------------------------
+UBool RBBITableBuilder::setEquals(UVector *a, UVector *b) {
+    return a->equals(*b);
+}
+
+
+//-----------------------------------------------------------------------------
+//
+//  printPosSets   Debug function.  Dump Nullable, firstpos, lastpos and followpos
+//                 for each node in the tree.
+//
+//-----------------------------------------------------------------------------
+#ifdef RBBI_DEBUG
+void RBBITableBuilder::printPosSets(RBBINode *n) {
+    if (n==NULL) {
+        return;
+    }
+    n->printNode();
+    RBBIDebugPrintf("         Nullable:  %s\n", n->fNullable?"TRUE":"FALSE");
+
+    RBBIDebugPrintf("         firstpos:  ");
+    printSet(n->fFirstPosSet);
+
+    RBBIDebugPrintf("         lastpos:   ");
+    printSet(n->fLastPosSet);
+
+    RBBIDebugPrintf("         followpos: ");
+    printSet(n->fFollowPos);
+
+    printPosSets(n->fLeftChild);
+    printPosSets(n->fRightChild);
+}
+#endif
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   getTableSize()    Calculate the size of the runtime form of this
+//                     state transition table.
+//
+//-----------------------------------------------------------------------------
+int32_t  RBBITableBuilder::getTableSize() const {
+    int32_t    size = 0;
+    int32_t    numRows;
+    int32_t    numCols;
+    int32_t    rowSize;
+
+    if (fTree == NULL) {
+        return 0;
+    }
+
+    size    = sizeof(RBBIStateTable) - 4;    // The header, with no rows to the table.
+
+    numRows = fDStates->size();
+    numCols = fRB->fSetBuilder->getNumCharCategories();
+
+    //  Note  The declaration of RBBIStateTableRow is for a table of two columns.
+    //        Therefore we subtract two from numCols when determining
+    //        how much storage to add to a row for the total columns.
+    rowSize = sizeof(RBBIStateTableRow) + sizeof(uint16_t)*(numCols-2);
+    size   += numRows * rowSize;
+    return size;
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   exportTable()    export the state transition table in the format required
+//                    by the runtime engine.  getTableSize() bytes of memory
+//                    must be available at the output address "where".
+//
+//-----------------------------------------------------------------------------
+void RBBITableBuilder::exportTable(void *where) {
+    RBBIStateTable    *table = (RBBIStateTable *)where;
+    uint32_t           state;
+    int                col;
+
+    if (U_FAILURE(*fStatus) || fTree == NULL) {
+        return;
+    }
+
+    if (fRB->fSetBuilder->getNumCharCategories() > 0x7fff ||
+        fDStates->size() > 0x7fff) {
+        *fStatus = U_BRK_INTERNAL_ERROR;
+        return;
+    }
+
+    table->fRowLen    = sizeof(RBBIStateTableRow) +
+                            sizeof(uint16_t) * (fRB->fSetBuilder->getNumCharCategories() - 2);
+    table->fNumStates = fDStates->size();
+    table->fFlags     = 0;
+    if (fRB->fLookAheadHardBreak) {
+        table->fFlags  |= RBBI_LOOKAHEAD_HARD_BREAK;
+    }
+    if (fRB->fSetBuilder->sawBOF()) {
+        table->fFlags  |= RBBI_BOF_REQUIRED;
+    }
+    table->fReserved  = 0;
+
+    for (state=0; state<table->fNumStates; state++) {
+        RBBIStateDescriptor *sd = (RBBIStateDescriptor *)fDStates->elementAt(state);
+        RBBIStateTableRow   *row = (RBBIStateTableRow *)(table->fTableData + state*table->fRowLen);
+        U_ASSERT (-32768 < sd->fAccepting && sd->fAccepting <= 32767);
+        U_ASSERT (-32768 < sd->fLookAhead && sd->fLookAhead <= 32767);
+        row->fAccepting = (int16_t)sd->fAccepting;
+        row->fLookAhead = (int16_t)sd->fLookAhead;
+        row->fTagIdx    = (int16_t)sd->fTagsIdx;
+        for (col=0; col<fRB->fSetBuilder->getNumCharCategories(); col++) {
+            row->fNextState[col] = (uint16_t)sd->fDtran->elementAti(col);
+        }
+    }
+}
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   printSet    Debug function.   Print the contents of a UVector
+//
+//-----------------------------------------------------------------------------
+#ifdef RBBI_DEBUG
+void RBBITableBuilder::printSet(UVector *s) {
+    int32_t  i;
+    for (i=0; i<s->size(); i++) {
+        void *v = s->elementAt(i);
+        RBBIDebugPrintf("%10p", v);
+    }
+    RBBIDebugPrintf("\n");
+}
+#endif
+
+
+//-----------------------------------------------------------------------------
+//
+//   printStates    Debug Function.  Dump the fully constructed state transition table.
+//
+//-----------------------------------------------------------------------------
+#ifdef RBBI_DEBUG
+void RBBITableBuilder::printStates() {
+    int     c;    // input "character"
+    int     n;    // state number
+
+    RBBIDebugPrintf("state |           i n p u t     s y m b o l s \n");
+    RBBIDebugPrintf("      | Acc  LA    Tag");
+    for (c=0; c<fRB->fSetBuilder->getNumCharCategories(); c++) {
+        RBBIDebugPrintf(" %2d", c);
+    }
+    RBBIDebugPrintf("\n");
+    RBBIDebugPrintf("      |---------------");
+    for (c=0; c<fRB->fSetBuilder->getNumCharCategories(); c++) {
+        RBBIDebugPrintf("---");
+    }
+    RBBIDebugPrintf("\n");
+
+    for (n=0; n<fDStates->size(); n++) {
+        RBBIStateDescriptor *sd = (RBBIStateDescriptor *)fDStates->elementAt(n);
+        RBBIDebugPrintf("  %3d | " , n);
+        RBBIDebugPrintf("%3d %3d %5d ", sd->fAccepting, sd->fLookAhead, sd->fTagsIdx);
+        for (c=0; c<fRB->fSetBuilder->getNumCharCategories(); c++) {
+            RBBIDebugPrintf(" %2d", sd->fDtran->elementAti(c));
+        }
+        RBBIDebugPrintf("\n");
+    }
+    RBBIDebugPrintf("\n\n");
+}
+#endif
+
+
+
+//-----------------------------------------------------------------------------
+//
+//   printRuleStatusTable    Debug Function.  Dump the common rule status table
+//
+//-----------------------------------------------------------------------------
+#ifdef RBBI_DEBUG
+void RBBITableBuilder::printRuleStatusTable() {
+    int32_t  thisRecord = 0;
+    int32_t  nextRecord = 0;
+    int      i;
+    UVector  *tbl = fRB->fRuleStatusVals;
+
+    RBBIDebugPrintf("index |  tags \n");
+    RBBIDebugPrintf("-------------------\n");
+
+    while (nextRecord < tbl->size()) {
+        thisRecord = nextRecord;
+        nextRecord = thisRecord + tbl->elementAti(thisRecord) + 1;
+        RBBIDebugPrintf("%4d   ", thisRecord);
+        for (i=thisRecord+1; i<nextRecord; i++) {
+            RBBIDebugPrintf("  %5d", tbl->elementAti(i));
+        }
+        RBBIDebugPrintf("\n");
+    }
+    RBBIDebugPrintf("\n\n");
+}
+#endif
+
+
+//-----------------------------------------------------------------------------
+//
+//   RBBIStateDescriptor     Methods.  This is a very struct-like class
+//                           Most access is directly to the fields.
+//
+//-----------------------------------------------------------------------------
+
+RBBIStateDescriptor::RBBIStateDescriptor(int lastInputSymbol, UErrorCode *fStatus) {
+    fMarked    = FALSE;
+    fAccepting = 0;
+    fLookAhead = 0;
+    fTagsIdx   = 0;
+    fTagVals   = NULL;
+    fPositions = NULL;
+    fDtran     = NULL;
+
+    fDtran     = new UVector(lastInputSymbol+1, *fStatus);
+    if (U_FAILURE(*fStatus)) {
+        return;
+    }
+    if (fDtran == NULL) {
+        *fStatus = U_MEMORY_ALLOCATION_ERROR;
+        return;
+    }
+    fDtran->setSize(lastInputSymbol+1, *fStatus);    // fDtran needs to be pre-sized.
+                                           //   It is indexed by input symbols, and will
+                                           //   hold  the next state number for each
+                                           //   symbol.
+}
+
+
+RBBIStateDescriptor::~RBBIStateDescriptor() {
+    delete       fPositions;
+    delete       fDtran;
+    delete       fTagVals;
+    fPositions = NULL;
+    fDtran     = NULL;
+    fTagVals   = NULL;
+}
+
+U_NAMESPACE_END
+
+#endif /* #if !UCONFIG_NO_BREAK_ITERATION */