/*--------------------------------------------------------------------*/ /*--- An AVL tree based finite map for word keys and word values. ---*/ /*--- Inspired by Haskell's "FiniteMap" library. ---*/ /*--- m_wordfm.c ---*/ /*--------------------------------------------------------------------*/ /* This file is part of Valgrind, a dynamic binary instrumentation framework. Copyright (C) 2007-2011 Julian Seward jseward@acm.org This code is based on previous work by Nicholas Nethercote (coregrind/m_oset.c) which is Copyright (C) 2005-2011 Nicholas Nethercote njn@valgrind.org which in turn was derived partially from: AVL C library Copyright (C) 2000,2002 Daniel Nagy This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. [...] (taken from libavl-0.4/debian/copyright) This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA. The GNU General Public License is contained in the file COPYING. */ #include "pub_core_basics.h" #include "pub_core_libcassert.h" #include "pub_core_libcbase.h" #include "pub_core_wordfm.h" /* self */ //------------------------------------------------------------------// //--- WordFM ---// //--- Implementation ---// //------------------------------------------------------------------// /* One element of the AVL tree */ typedef struct _AvlNode { UWord key; UWord val; struct _AvlNode* child[2]; /* [0] is left subtree, [1] is right */ Char balance; /* do not make this unsigned */ } AvlNode; typedef struct { UWord w; Bool b; } MaybeWord; #define WFM_STKMAX 32 // At most 2**32 entries can be iterated over struct _WordFM { AvlNode* root; void* (*alloc_nofail)( HChar*, SizeT ); HChar* cc; void (*dealloc)(void*); Word (*kCmp)(UWord,UWord); AvlNode* nodeStack[WFM_STKMAX]; // Iterator node stack Int numStack[WFM_STKMAX]; // Iterator num stack Int stackTop; // Iterator stack pointer, one past end }; /* forward */ static Bool avl_removeroot_wrk(AvlNode** t, Word(*kCmp)(UWord,UWord)); /* Swing to the left. Warning: no balance maintainance. */ static void avl_swl ( AvlNode** root ) { AvlNode* a = *root; AvlNode* b = a->child[1]; *root = b; a->child[1] = b->child[0]; b->child[0] = a; } /* Swing to the right. Warning: no balance maintainance. */ static void avl_swr ( AvlNode** root ) { AvlNode* a = *root; AvlNode* b = a->child[0]; *root = b; a->child[0] = b->child[1]; b->child[1] = a; } /* Balance maintainance after especially nasty swings. */ static void avl_nasty ( AvlNode* root ) { switch (root->balance) { case -1: root->child[0]->balance = 0; root->child[1]->balance = 1; break; case 1: root->child[0]->balance = -1; root->child[1]->balance = 0; break; case 0: root->child[0]->balance = 0; root->child[1]->balance = 0; break; default: tl_assert(0); } root->balance=0; } /* Find size of a non-NULL tree. */ static UWord size_avl_nonNull ( AvlNode* nd ) { return 1 + (nd->child[0] ? size_avl_nonNull(nd->child[0]) : 0) + (nd->child[1] ? size_avl_nonNull(nd->child[1]) : 0); } /* Unsignedly compare w1 and w2. If w1 < w2, produce a negative number; if w1 > w2 produce a positive number, and if w1 == w2 produce zero. */ static inline Word cmp_unsigned_Words ( UWord w1, UWord w2 ) { if (w1 < w2) return -1; if (w1 > w2) return 1; return 0; } /* Insert element a into the AVL tree t. Returns True if the depth of the tree has grown. If element with that key is already present, just copy a->val to existing node, first returning old ->val field of existing node in *oldV, so that the caller can finalize it however it wants. */ static Bool avl_insert_wrk ( AvlNode** rootp, /*OUT*/MaybeWord* oldV, AvlNode* a, Word (*kCmp)(UWord,UWord) ) { Word cmpres; /* initialize */ a->child[0] = 0; a->child[1] = 0; a->balance = 0; oldV->b = False; /* insert into an empty tree? */ if (!(*rootp)) { (*rootp) = a; return True; } cmpres = kCmp ? /*boxed*/ kCmp( (*rootp)->key, a->key ) : /*unboxed*/ cmp_unsigned_Words( (UWord)(*rootp)->key, (UWord)a->key ); if (cmpres > 0) { /* insert into the left subtree */ if ((*rootp)->child[0]) { AvlNode* left_subtree = (*rootp)->child[0]; if (avl_insert_wrk(&left_subtree, oldV, a, kCmp)) { switch ((*rootp)->balance--) { case 1: return False; case 0: return True; case -1: break; default: tl_assert(0); } if ((*rootp)->child[0]->balance < 0) { avl_swr( rootp ); (*rootp)->balance = 0; (*rootp)->child[1]->balance = 0; } else { avl_swl( &((*rootp)->child[0]) ); avl_swr( rootp ); avl_nasty( *rootp ); } } else { (*rootp)->child[0] = left_subtree; } return False; } else { (*rootp)->child[0] = a; if ((*rootp)->balance--) return False; return True; } tl_assert(0);/*NOTREACHED*/ } else if (cmpres < 0) { /* insert into the right subtree */ if ((*rootp)->child[1]) { AvlNode* right_subtree = (*rootp)->child[1]; if (avl_insert_wrk(&right_subtree, oldV, a, kCmp)) { switch((*rootp)->balance++){ case -1: return False; case 0: return True; case 1: break; default: tl_assert(0); } if ((*rootp)->child[1]->balance > 0) { avl_swl( rootp ); (*rootp)->balance = 0; (*rootp)->child[0]->balance = 0; } else { avl_swr( &((*rootp)->child[1]) ); avl_swl( rootp ); avl_nasty( *rootp ); } } else { (*rootp)->child[1] = right_subtree; } return False; } else { (*rootp)->child[1] = a; if ((*rootp)->balance++) return False; return True; } tl_assert(0);/*NOTREACHED*/ } else { /* cmpres == 0, a duplicate - replace the val, but don't incorporate the node in the tree */ oldV->b = True; oldV->w = (*rootp)->val; (*rootp)->val = a->val; return False; } } /* Remove an element a from the AVL tree t. a must be part of the tree. Returns True if the depth of the tree has shrunk. */ static Bool avl_remove_wrk ( AvlNode** rootp, AvlNode* a, Word(*kCmp)(UWord,UWord) ) { Bool ch; Word cmpres; cmpres = kCmp ? /*boxed*/ kCmp( (*rootp)->key, a->key ) : /*unboxed*/ cmp_unsigned_Words( (UWord)(*rootp)->key, (UWord)a->key ); if (cmpres > 0){ /* remove from the left subtree */ AvlNode* left_subtree = (*rootp)->child[0]; tl_assert(left_subtree); ch = avl_remove_wrk(&left_subtree, a, kCmp); (*rootp)->child[0]=left_subtree; if (ch) { switch ((*rootp)->balance++) { case -1: return True; case 0: return False; case 1: break; default: tl_assert(0); } switch ((*rootp)->child[1]->balance) { case 0: avl_swl( rootp ); (*rootp)->balance = -1; (*rootp)->child[0]->balance = 1; return False; case 1: avl_swl( rootp ); (*rootp)->balance = 0; (*rootp)->child[0]->balance = 0; return True; case -1: break; default: tl_assert(0); } avl_swr( &((*rootp)->child[1]) ); avl_swl( rootp ); avl_nasty( *rootp ); return True; } } else if (cmpres < 0) { /* remove from the right subtree */ AvlNode* right_subtree = (*rootp)->child[1]; tl_assert(right_subtree); ch = avl_remove_wrk(&right_subtree, a, kCmp); (*rootp)->child[1] = right_subtree; if (ch) { switch ((*rootp)->balance--) { case 1: return True; case 0: return False; case -1: break; default: tl_assert(0); } switch ((*rootp)->child[0]->balance) { case 0: avl_swr( rootp ); (*rootp)->balance = 1; (*rootp)->child[1]->balance = -1; return False; case -1: avl_swr( rootp ); (*rootp)->balance = 0; (*rootp)->child[1]->balance = 0; return True; case 1: break; default: tl_assert(0); } avl_swl( &((*rootp)->child[0]) ); avl_swr( rootp ); avl_nasty( *rootp ); return True; } } else { tl_assert(cmpres == 0); tl_assert((*rootp)==a); return avl_removeroot_wrk(rootp, kCmp); } return 0; } /* Remove the root of the AVL tree *rootp. * Warning: dumps core if *rootp is empty */ static Bool avl_removeroot_wrk ( AvlNode** rootp, Word(*kCmp)(UWord,UWord) ) { Bool ch; AvlNode* a; if (!(*rootp)->child[0]) { if (!(*rootp)->child[1]) { (*rootp) = 0; return True; } (*rootp) = (*rootp)->child[1]; return True; } if (!(*rootp)->child[1]) { (*rootp) = (*rootp)->child[0]; return True; } if ((*rootp)->balance < 0) { /* remove from the left subtree */ a = (*rootp)->child[0]; while (a->child[1]) a = a->child[1]; } else { /* remove from the right subtree */ a = (*rootp)->child[1]; while (a->child[0]) a = a->child[0]; } ch = avl_remove_wrk(rootp, a, kCmp); a->child[0] = (*rootp)->child[0]; a->child[1] = (*rootp)->child[1]; a->balance = (*rootp)->balance; (*rootp) = a; if(a->balance == 0) return ch; return False; } static AvlNode* avl_find_node ( AvlNode* t, Word k, Word(*kCmp)(UWord,UWord) ) { if (kCmp) { /* Boxed comparisons */ Word cmpresS; while (True) { if (t == NULL) return NULL; cmpresS = kCmp(t->key, k); if (cmpresS > 0) t = t->child[0]; else if (cmpresS < 0) t = t->child[1]; else return t; } } else { /* Unboxed comparisons */ Word cmpresS; /* signed */ UWord cmpresU; /* unsigned */ while (True) { if (t == NULL) return NULL; /* unlikely ==> predictable */ cmpresS = cmp_unsigned_Words( (UWord)t->key, (UWord)k ); if (cmpresS == 0) return t; /* unlikely ==> predictable */ cmpresU = (UWord)cmpresS; cmpresU >>=/*unsigned*/ (8 * sizeof(cmpresU) - 1); t = t->child[cmpresU]; } } } static Bool avl_find_bounds ( AvlNode* t, /*OUT*/UWord* kMinP, /*OUT*/UWord* vMinP, /*OUT*/UWord* kMaxP, /*OUT*/UWord* vMaxP, UWord minKey, UWord minVal, UWord maxKey, UWord maxVal, UWord key, Word(*kCmp)(UWord,UWord) ) { UWord kLowerBound = minKey; UWord vLowerBound = minVal; UWord kUpperBound = maxKey; UWord vUpperBound = maxVal; while (t) { Word cmpresS = kCmp ? kCmp(t->key, key) : cmp_unsigned_Words(t->key, key); if (cmpresS < 0) { kLowerBound = t->key; vLowerBound = t->val; t = t->child[1]; continue; } if (cmpresS > 0) { kUpperBound = t->key; vUpperBound = t->val; t = t->child[0]; continue; } /* We should never get here. If we do, it means the given key is actually present in the tree, which means the original call was invalid -- an error on the caller's part, and we cannot give any meaningful values for the bounds. (Well, maybe we could, but we're not gonna. Ner!) */ return False; } if (kMinP) *kMinP = kLowerBound; if (vMinP) *vMinP = vLowerBound; if (kMaxP) *kMaxP = kUpperBound; if (vMaxP) *vMaxP = vUpperBound; return True; } // Clear the iterator stack. static void stackClear(WordFM* fm) { Int i; tl_assert(fm); for (i = 0; i < WFM_STKMAX; i++) { fm->nodeStack[i] = NULL; fm->numStack[i] = 0; } fm->stackTop = 0; } // Push onto the iterator stack. static inline void stackPush(WordFM* fm, AvlNode* n, Int i) { tl_assert(fm->stackTop < WFM_STKMAX); tl_assert(1 <= i && i <= 3); fm->nodeStack[fm->stackTop] = n; fm-> numStack[fm->stackTop] = i; fm->stackTop++; } // Pop from the iterator stack. static inline Bool stackPop(WordFM* fm, AvlNode** n, Int* i) { tl_assert(fm->stackTop <= WFM_STKMAX); if (fm->stackTop > 0) { fm->stackTop--; *n = fm->nodeStack[fm->stackTop]; *i = fm-> numStack[fm->stackTop]; tl_assert(1 <= *i && *i <= 3); fm->nodeStack[fm->stackTop] = NULL; fm-> numStack[fm->stackTop] = 0; return True; } else { return False; } } static AvlNode* avl_dopy ( AvlNode* nd, UWord(*dopyK)(UWord), UWord(*dopyV)(UWord), void*(alloc_nofail)(HChar*,SizeT), HChar* cc ) { AvlNode* nyu; if (! nd) return NULL; nyu = alloc_nofail(cc, sizeof(AvlNode)); tl_assert(nyu); nyu->child[0] = nd->child[0]; nyu->child[1] = nd->child[1]; nyu->balance = nd->balance; /* Copy key */ if (dopyK) { nyu->key = dopyK( nd->key ); if (nd->key != 0 && nyu->key == 0) return NULL; /* oom in key dcopy */ } else { /* copying assumedly unboxed keys */ nyu->key = nd->key; } /* Copy val */ if (dopyV) { nyu->val = dopyV( nd->val ); if (nd->val != 0 && nyu->val == 0) return NULL; /* oom in val dcopy */ } else { /* copying assumedly unboxed vals */ nyu->val = nd->val; } /* Copy subtrees */ if (nyu->child[0]) { nyu->child[0] = avl_dopy( nyu->child[0], dopyK, dopyV, alloc_nofail, cc ); if (! nyu->child[0]) return NULL; } if (nyu->child[1]) { nyu->child[1] = avl_dopy( nyu->child[1], dopyK, dopyV, alloc_nofail, cc ); if (! nyu->child[1]) return NULL; } return nyu; } /* Initialise a WordFM. */ static void initFM ( WordFM* fm, void* (*alloc_nofail)( HChar*, SizeT ), HChar* cc, void (*dealloc)(void*), Word (*kCmp)(UWord,UWord) ) { fm->root = 0; fm->kCmp = kCmp; fm->alloc_nofail = alloc_nofail; fm->cc = cc; fm->dealloc = dealloc; fm->stackTop = 0; } /* --- Public interface functions --- */ /* Allocate and initialise a WordFM. If kCmp is non-NULL, elements in the set are ordered according to the ordering specified by kCmp, which becomes obvious if you use VG_(initIterFM), VG_(initIterAtFM), VG_(nextIterFM), VG_(doneIterFM) to iterate over sections of the map, or the whole thing. If kCmp is NULL then the ordering used is unsigned word ordering (UWord) on the key values. */ WordFM* VG_(newFM) ( void* (*alloc_nofail)( HChar*, SizeT ), HChar* cc, void (*dealloc)(void*), Word (*kCmp)(UWord,UWord) ) { WordFM* fm = alloc_nofail(cc, sizeof(WordFM)); tl_assert(fm); initFM(fm, alloc_nofail, cc, dealloc, kCmp); return fm; } static void avl_free ( AvlNode* nd, void(*kFin)(UWord), void(*vFin)(UWord), void(*dealloc)(void*) ) { if (!nd) return; if (nd->child[0]) avl_free(nd->child[0], kFin, vFin, dealloc); if (nd->child[1]) avl_free(nd->child[1], kFin, vFin, dealloc); if (kFin) kFin( nd->key ); if (vFin) vFin( nd->val ); VG_(memset)(nd, 0, sizeof(AvlNode)); dealloc(nd); } /* Free up the FM. If kFin is non-NULL, it is applied to keys before the FM is deleted; ditto with vFin for vals. */ void VG_(deleteFM) ( WordFM* fm, void(*kFin)(UWord), void(*vFin)(UWord) ) { void(*dealloc)(void*) = fm->dealloc; avl_free( fm->root, kFin, vFin, dealloc ); VG_(memset)(fm, 0, sizeof(WordFM) ); dealloc(fm); } /* Add (k,v) to fm. */ Bool VG_(addToFM) ( WordFM* fm, UWord k, UWord v ) { MaybeWord oldV; AvlNode* node; node = fm->alloc_nofail( fm->cc, sizeof(AvlNode) ); node->key = k; node->val = v; oldV.b = False; oldV.w = 0; avl_insert_wrk( &fm->root, &oldV, node, fm->kCmp ); //if (oldV.b && fm->vFin) // fm->vFin( oldV.w ); if (oldV.b) fm->dealloc(node); return oldV.b; } // Delete key from fm, returning associated key and val if found Bool VG_(delFromFM) ( WordFM* fm, /*OUT*/UWord* oldK, /*OUT*/UWord* oldV, UWord key ) { AvlNode* node = avl_find_node( fm->root, key, fm->kCmp ); if (node) { avl_remove_wrk( &fm->root, node, fm->kCmp ); if (oldK) *oldK = node->key; if (oldV) *oldV = node->val; fm->dealloc(node); return True; } else { return False; } } // Look up in fm, assigning found key & val at spec'd addresses Bool VG_(lookupFM) ( WordFM* fm, /*OUT*/UWord* keyP, /*OUT*/UWord* valP, UWord key ) { AvlNode* node = avl_find_node( fm->root, key, fm->kCmp ); if (node) { if (keyP) *keyP = node->key; if (valP) *valP = node->val; return True; } else { return False; } } // See comment in pub_tool_wordfm.h for explanation Bool VG_(findBoundsFM)( WordFM* fm, /*OUT*/UWord* kMinP, /*OUT*/UWord* vMinP, /*OUT*/UWord* kMaxP, /*OUT*/UWord* vMaxP, UWord minKey, UWord minVal, UWord maxKey, UWord maxVal, UWord key ) { /* really we should assert that minKey <= key <= maxKey, where <= is as defined by fm->kCmp. */ return avl_find_bounds( fm->root, kMinP, vMinP, kMaxP, vMaxP, minKey, minVal, maxKey, maxVal, key, fm->kCmp ); } // See comment in pub_tool_wordfm.h for performance warning UWord VG_(sizeFM) ( WordFM* fm ) { // Hmm, this is a bad way to do this return fm->root ? size_avl_nonNull( fm->root ) : 0; } // NB UNTESTED! TEST BEFORE USE! //Bool VG_(isEmptyFM)( WordFM* fm ) //{ // return fm->root ? False : True; //} // set up FM for iteration void VG_(initIterFM) ( WordFM* fm ) { tl_assert(fm); stackClear(fm); if (fm->root) stackPush(fm, fm->root, 1); } // set up FM for iteration so that the first key subsequently produced // by VG_(nextIterFM) is the smallest key in the map >= start_at. // Naturally ">=" is defined by the comparison function supplied to // VG_(newFM), as documented above. void VG_(initIterAtFM) ( WordFM* fm, UWord start_at ) { Int i; AvlNode *n, *t; Word cmpresS; /* signed */ UWord cmpresU; /* unsigned */ tl_assert(fm); stackClear(fm); if (!fm->root) return; n = NULL; // We need to do regular search and fill in the stack. t = fm->root; while (True) { if (t == NULL) return; cmpresS = fm->kCmp ? /*boxed*/ fm->kCmp( t->key, start_at ) : /*unboxed*/ cmp_unsigned_Words( t->key, start_at ); if (cmpresS == 0) { // We found the exact key -- we are done. // The iteration should start with this node. stackPush(fm, t, 2); // The stack now looks like {2, 2, ... ,2, 2} return; } cmpresU = (UWord)cmpresS; cmpresU >>=/*unsigned*/ (8 * sizeof(cmpresU) - 1); if (!cmpresU) { // Push this node only if we go to the left child. stackPush(fm, t, 2); } t = t->child[cmpresU]; } if (stackPop(fm, &n, &i)) { // If we've pushed something to stack and did not find the exact key, // we must fix the top element of stack. tl_assert(i == 2); stackPush(fm, n, 3); // the stack looks like {2, 2, ..., 2, 3} } } // get next key/val pair. Will tl_assert if fm has been modified // or looked up in since initIter{,At}FM was called. Bool VG_(nextIterFM) ( WordFM* fm, /*OUT*/UWord* pKey, /*OUT*/UWord* pVal ) { Int i = 0; AvlNode* n = NULL; tl_assert(fm); // This in-order traversal requires each node to be pushed and popped // three times. These could be avoided by updating nodes in-situ on the // top of the stack, but the push/pop cost is so small that it's worth // keeping this loop in this simpler form. while (stackPop(fm, &n, &i)) { switch (i) { case 1: case_1: stackPush(fm, n, 2); /* if (n->child[0]) stackPush(fm, n->child[0], 1); */ if (n->child[0]) { n = n->child[0]; goto case_1; } break; case 2: stackPush(fm, n, 3); if (pKey) *pKey = n->key; if (pVal) *pVal = n->val; return True; case 3: /* if (n->child[1]) stackPush(fm, n->child[1], 1); */ if (n->child[1]) { n = n->child[1]; goto case_1; } break; default: tl_assert(0); } } // Stack empty, iterator is exhausted, return NULL return False; } // clear the I'm iterating flag void VG_(doneIterFM) ( WordFM* fm ) { } WordFM* VG_(dopyFM) ( WordFM* fm, UWord(*dopyK)(UWord), UWord(*dopyV)(UWord) ) { WordFM* nyu; /* can't clone the fm whilst iterating on it */ tl_assert(fm->stackTop == 0); nyu = fm->alloc_nofail( fm->cc, sizeof(WordFM) ); tl_assert(nyu); *nyu = *fm; fm->stackTop = 0; VG_(memset)(fm->nodeStack, 0, sizeof(fm->nodeStack)); VG_(memset)(fm->numStack, 0, sizeof(fm->numStack)); if (nyu->root) { nyu->root = avl_dopy( nyu->root, dopyK, dopyV, fm->alloc_nofail, fm->cc ); if (! nyu->root) return NULL; } return nyu; } // admin: what's the 'common' allocation size (for tree nodes?) SizeT VG_(getNodeSizeFM)( void ) { return sizeof(AvlNode); } //------------------------------------------------------------------// //--- end WordFM ---// //--- Implementation ---// //------------------------------------------------------------------// //------------------------------------------------------------------// //--- WordBag (unboxed words only) ---// //--- Implementation ---// //------------------------------------------------------------------// /* A trivial container, to make it opaque. */ struct _WordBag { WordFM* fm; }; WordBag* VG_(newBag) ( void* (*alloc_nofail)( HChar*, SizeT ), HChar* cc, void (*dealloc)(void*) ) { WordBag* bag = alloc_nofail(cc, sizeof(WordBag)); bag->fm = VG_(newFM)( alloc_nofail, cc, dealloc, NULL ); return bag; } void VG_(deleteBag) ( WordBag* bag ) { void (*dealloc)(void*) = bag->fm->dealloc; VG_(deleteFM)( bag->fm, NULL, NULL ); VG_(memset)(bag, 0, sizeof(WordBag)); dealloc(bag); } void VG_(addToBag)( WordBag* bag, UWord w ) { UWord key, count; if (VG_(lookupFM)(bag->fm, &key, &count, w)) { tl_assert(key == w); tl_assert(count >= 1); VG_(addToFM)(bag->fm, w, count+1); } else { VG_(addToFM)(bag->fm, w, 1); } } UWord VG_(elemBag) ( WordBag* bag, UWord w ) { UWord key, count; if (VG_(lookupFM)( bag->fm, &key, &count, w)) { tl_assert(key == w); tl_assert(count >= 1); return count; } else { return 0; } } UWord VG_(sizeUniqueBag) ( WordBag* bag ) { return VG_(sizeFM)( bag->fm ); } static UWord sizeTotalBag_wrk ( AvlNode* nd ) { /* unchecked pre: nd is non-NULL */ UWord w = nd->val; tl_assert(w >= 1); if (nd->child[0]) w += sizeTotalBag_wrk(nd->child[0]); if (nd->child[1]) w += sizeTotalBag_wrk(nd->child[1]); return w; } UWord VG_(sizeTotalBag)( WordBag* bag ) { if (bag->fm->root) return sizeTotalBag_wrk(bag->fm->root); else return 0; } Bool VG_(delFromBag)( WordBag* bag, UWord w ) { UWord key, count; if (VG_(lookupFM)(bag->fm, &key, &count, w)) { tl_assert(key == w); tl_assert(count >= 1); if (count > 1) { VG_(addToFM)(bag->fm, w, count-1); } else { tl_assert(count == 1); VG_(delFromFM)( bag->fm, NULL, NULL, w ); } return True; } else { return False; } } Bool VG_(isEmptyBag)( WordBag* bag ) { return VG_(sizeFM)(bag->fm) == 0; } Bool VG_(isSingletonTotalBag)( WordBag* bag ) { AvlNode* nd; if (VG_(sizeFM)(bag->fm) != 1) return False; nd = bag->fm->root; tl_assert(nd); tl_assert(!nd->child[0]); tl_assert(!nd->child[1]); return nd->val == 1; } UWord VG_(anyElementOfBag)( WordBag* bag ) { /* Return an arbitrarily chosen element in the bag. We might as well return the one at the root of the underlying AVL tree. */ AvlNode* nd = bag->fm->root; tl_assert(nd); /* if this fails, 'bag' is empty - caller is in error. */ tl_assert(nd->val >= 1); return nd->key; } void VG_(initIterBag)( WordBag* bag ) { VG_(initIterFM)(bag->fm); } Bool VG_(nextIterBag)( WordBag* bag, /*OUT*/UWord* pVal, /*OUT*/UWord* pCount ) { return VG_(nextIterFM)( bag->fm, pVal, pCount ); } void VG_(doneIterBag)( WordBag* bag ) { VG_(doneIterFM)( bag->fm ); } //------------------------------------------------------------------// //--- end WordBag (unboxed words only) ---// //--- Implementation ---// //------------------------------------------------------------------// /*--------------------------------------------------------------------*/ /*--- end m_wordfm.c ---*/ /*--------------------------------------------------------------------*/