1c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner//===- llvm/ADT/SmallPtrSet.h - 'Normally small' pointer set ----*- C++ -*-===// 2c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner// 3c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner// The LLVM Compiler Infrastructure 4c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner// 57ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// This file is distributed under the University of Illinois Open Source 67ed47a13356daed2a34cd2209a31f92552e3bdd8Chris Lattner// License. See LICENSE.TXT for details. 7c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner// 8c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner//===----------------------------------------------------------------------===// 9c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner// 1018b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner// This file defines the SmallPtrSet class. See the doxygen comment for 1118b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner// SmallPtrSetImpl for more details on the algorithm used. 12c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner// 13c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner//===----------------------------------------------------------------------===// 14c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 15c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner#ifndef LLVM_ADT_SMALLPTRSET_H 16c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner#define LLVM_ADT_SMALLPTRSET_H 17c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 18f630e49efc7bf3f1716b6daab3c2cc11a908754aCraig Topper#include "llvm/Support/Compiler.h" 19f630e49efc7bf3f1716b6daab3c2cc11a908754aCraig Topper#include "llvm/Support/DataTypes.h" 20f630e49efc7bf3f1716b6daab3c2cc11a908754aCraig Topper#include "llvm/Support/PointerLikeTypeTraits.h" 21c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner#include <cassert> 22476b242fe7a61e5f9ac6214b0bc5c680d24f152eNick Lewycky#include <cstddef> 23c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner#include <cstring> 247c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor#include <iterator> 25c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 26c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnernamespace llvm { 27c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 285471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohmanclass SmallPtrSetIteratorImpl; 295471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman 3018b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// SmallPtrSetImpl - This is the common code shared among all the 3118b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// SmallPtrSet<>'s, which is almost everything. SmallPtrSet has two modes, one 3218b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// for small and one for large sets. 3318b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// 3418b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// Small sets use an array of pointers allocated in the SmallPtrSet object, 3518b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// which is treated as a simple array of pointers. When a pointer is added to 3618b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// the set, the array is scanned to see if the element already exists, if not 3718b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// the element is 'pushed back' onto the array. If we run out of space in the 3818b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// array, we grow into the 'large set' case. SmallSet should be used when the 3918b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// sets are often small. In this case, no memory allocation is used, and only 4018b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// light-weight and cache-efficient scanning is used. 4118b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// 4218b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// Large sets use a classic exponentially-probed hash table. Empty buckets are 4318b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// represented with an illegal pointer value (-1) to allow null pointers to be 4418b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// inserted. Tombstones are represented with another illegal pointer value 4518b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// (-2), to allow deletion. The hash table is resized when the table is 3/4 or 4618b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// more. When this happens, the table is doubled in size. 4718b69106b7a66ac6abde37d1be6d0d952796ed04Chris Lattner/// 48c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerclass SmallPtrSetImpl { 495471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman friend class SmallPtrSetIteratorImpl; 50c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerprotected: 512a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands /// SmallArray - Points to a fixed size set of buckets, used in 'small mode'. 522a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands const void **SmallArray; 532a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands /// CurArray - This is the current set of buckets. If equal to SmallArray, 542a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands /// then the set is in 'small mode'. 55e992a56ae93140171f5044079e8d317f784c8cc1Owen Anderson const void **CurArray; 56c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// CurArraySize - The allocated size of CurArray, always a power of two. 57c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// Note that CurArray points to an array that has CurArraySize+1 elements in 58c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// it, so that the end iterator actually points to valid memory. 59c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner unsigned CurArraySize; 603a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 61ab4c366274a582dd8146b2820c6b999cad5fce36Duncan Sands // If small, this is # elts allocated consecutively 62c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner unsigned NumElements; 63e237cf934fcb8a25746e068f543fbd6db44eaa70Chris Lattner unsigned NumTombstones; 64ac58a16f8584f38198cc7800bd37a896125268b7Jeff Cohen 65ac58a16f8584f38198cc7800bd37a896125268b7Jeff Cohen // Helper to copy construct a SmallPtrSet. 662a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands SmallPtrSetImpl(const void **SmallStorage, const SmallPtrSetImpl& that); 672a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands explicit SmallPtrSetImpl(const void **SmallStorage, unsigned SmallSize) : 682a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands SmallArray(SmallStorage), CurArray(SmallStorage), CurArraySize(SmallSize) { 69c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner assert(SmallSize && (SmallSize & (SmallSize-1)) == 0 && 70c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner "Initial size must be a power of two!"); 71c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner // The end pointer, always valid, is set to a valid element to help the 72c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner // iterator. 73c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner CurArray[SmallSize] = 0; 74c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner clear(); 75c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 76845b31de0c58e1f667063170191262079d311052Reid Spencer ~SmallPtrSetImpl(); 773a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 785471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohmanpublic: 79894d264f3ee965645656ddd6566acbe4d3a3ed55Chris Lattner bool empty() const { return size() == 0; } 80894d264f3ee965645656ddd6566acbe4d3a3ed55Chris Lattner unsigned size() const { return NumElements; } 813a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 82c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner void clear() { 8342e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner // If the capacity of the array is huge, and the # elements used is small, 8442e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner // shrink the array. 8542e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner if (!isSmall() && NumElements*4 < CurArraySize && CurArraySize > 32) 8642e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner return shrink_and_clear(); 873a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 88c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner // Fill the array with empty markers. 89c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner memset(CurArray, -1, CurArraySize*sizeof(void*)); 90c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner NumElements = 0; 91e237cf934fcb8a25746e068f543fbd6db44eaa70Chris Lattner NumTombstones = 0; 92c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 933a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 94373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattnerprotected: 955471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman static void *getTombstoneMarker() { return reinterpret_cast<void*>(-2); } 965471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman static void *getEmptyMarker() { 975471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman // Note that -1 is chosen to make clear() efficiently implementable with 985471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman // memset and because it's not a valid pointer value. 995471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman return reinterpret_cast<void*>(-1); 1005471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman } 1015471a00977ab8ce3c88414dfbad99c0296d58508Dan Gohman 102373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// insert_imp - This returns true if the pointer was new to the set, false if 103373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// it was already in the set. This is hidden from the client so that the 104373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// derived class can check that the right type of pointer is passed in. 105373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner bool insert_imp(const void * Ptr); 1063a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 107373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// erase_imp - If the set contains the specified pointer, remove it and 108373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// return true, otherwise return false. This is hidden from the client so 109373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// that the derived class can check that the right type of pointer is passed 110373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// in. 111373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner bool erase_imp(const void * Ptr); 1123a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 113373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner bool count_imp(const void * Ptr) const { 114c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner if (isSmall()) { 115c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner // Linear search for the item. 11642e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner for (const void *const *APtr = SmallArray, 11742e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner *const *E = SmallArray+NumElements; APtr != E; ++APtr) 118c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner if (*APtr == Ptr) 119c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return true; 120c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return false; 121c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 1223a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 123c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner // Big set case. 124c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return *FindBucketFor(Ptr) == Ptr; 125c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 1263a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 127c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerprivate: 1282a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands bool isSmall() const { return CurArray == SmallArray; } 1290b930852cf1a9899ae82dd6c31b43e754a77dcb0Chris Lattner 130e992a56ae93140171f5044079e8d317f784c8cc1Owen Anderson const void * const *FindBucketFor(const void *Ptr) const; 13142e4bdf2577946380ce1529d5716e48b33d4186dChris Lattner void shrink_and_clear(); 1323a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 133c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// Grow - Allocate a larger backing store for the buckets and move it over. 134e10fff6f8802d6ab4045d9d0bb22e6f37e6d3d0bJakob Stoklund Olesen void Grow(unsigned NewSize); 1353a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 136f630e49efc7bf3f1716b6daab3c2cc11a908754aCraig Topper void operator=(const SmallPtrSetImpl &RHS) LLVM_DELETED_FUNCTION; 13791f0158d4d1b16b8615126b05582d421cfb14089Chris Lattnerprotected: 1382945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer /// swap - Swaps the elements of two sets. 1392945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer /// Note: This method assumes that both sets have the same small size. 1402945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer void swap(SmallPtrSetImpl &RHS); 1412945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer 14291f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner void CopyFrom(const SmallPtrSetImpl &RHS); 143c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner}; 144c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 145c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner/// SmallPtrSetIteratorImpl - This is the common base class shared between all 146c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner/// instances of SmallPtrSetIterator. 147c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerclass SmallPtrSetIteratorImpl { 148c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerprotected: 149e992a56ae93140171f5044079e8d317f784c8cc1Owen Anderson const void *const *Bucket; 150c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerpublic: 151950a4c40b823cd4f09dc71be635229246dfd6cacDan Gohman explicit SmallPtrSetIteratorImpl(const void *const *BP) : Bucket(BP) { 152c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner AdvanceIfNotValid(); 153c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 1543a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 155c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner bool operator==(const SmallPtrSetIteratorImpl &RHS) const { 156c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return Bucket == RHS.Bucket; 157c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 158c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner bool operator!=(const SmallPtrSetIteratorImpl &RHS) const { 159c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return Bucket != RHS.Bucket; 160c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 1613a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 162c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerprotected: 163c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// AdvanceIfNotValid - If the current bucket isn't valid, advance to a bucket 164c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// that is. This is guaranteed to stop because the end() bucket is marked 165c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner /// valid. 166c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner void AdvanceIfNotValid() { 167c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner while (*Bucket == SmallPtrSetImpl::getEmptyMarker() || 168c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner *Bucket == SmallPtrSetImpl::getTombstoneMarker()) 169c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner ++Bucket; 170c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 171c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner}; 172c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 173c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner/// SmallPtrSetIterator - This implements a const_iterator for SmallPtrSet. 174c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnertemplate<typename PtrTy> 175c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerclass SmallPtrSetIterator : public SmallPtrSetIteratorImpl { 1768ee1b5e916249d1a64ad8cf99b08a0e160f9d052Chris Lattner typedef PointerLikeTypeTraits<PtrTy> PtrTraits; 1777c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor 178c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerpublic: 1797c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor typedef PtrTy value_type; 1807c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor typedef PtrTy reference; 1817c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor typedef PtrTy pointer; 1827c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor typedef std::ptrdiff_t difference_type; 1837c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor typedef std::forward_iterator_tag iterator_category; 1847c718222cdb624f4c420b3d7b6eeb12fffc05603Douglas Gregor 185950a4c40b823cd4f09dc71be635229246dfd6cacDan Gohman explicit SmallPtrSetIterator(const void *const *BP) 186950a4c40b823cd4f09dc71be635229246dfd6cacDan Gohman : SmallPtrSetIteratorImpl(BP) {} 187c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 188c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner // Most methods provided by baseclass. 1893a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 190e992a56ae93140171f5044079e8d317f784c8cc1Owen Anderson const PtrTy operator*() const { 1916de603071879bdc5d7d663826354c24a9d176469Chris Lattner return PtrTraits::getFromVoidPointer(const_cast<void*>(*Bucket)); 192c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 1933a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 194c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner inline SmallPtrSetIterator& operator++() { // Preincrement 195c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner ++Bucket; 196c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner AdvanceIfNotValid(); 197c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return *this; 198c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 1993a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 200c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner SmallPtrSetIterator operator++(int) { // Postincrement 201c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner SmallPtrSetIterator tmp = *this; ++*this; return tmp; 202c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 203c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner}; 204c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 205a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sands/// RoundUpToPowerOfTwo - This is a helper template that rounds N up to the next 2062e502577ab3645ab5c54434671d299e35c2245ccDuncan Sands/// power of two (which means N itself if N is already a power of two). 207af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattnertemplate<unsigned N> 208a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sandsstruct RoundUpToPowerOfTwo; 209af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner 210a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sands/// RoundUpToPowerOfTwoH - If N is not a power of two, increase it. This is a 211a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sands/// helper template used to implement RoundUpToPowerOfTwo. 212af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattnertemplate<unsigned N, bool isPowerTwo> 213a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sandsstruct RoundUpToPowerOfTwoH { 214af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner enum { Val = N }; 215af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner}; 216af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattnertemplate<unsigned N> 217a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sandsstruct RoundUpToPowerOfTwoH<N, false> { 218af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner enum { 219af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner // We could just use NextVal = N+1, but this converges faster. N|(N-1) sets 220af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner // the right-most zero bits to one all at once, e.g. 0b0011000 -> 0b0011111. 221a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sands Val = RoundUpToPowerOfTwo<(N|(N-1)) + 1>::Val 222af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner }; 223af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner}; 224af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner 225af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattnertemplate<unsigned N> 226a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sandsstruct RoundUpToPowerOfTwo { 227a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sands enum { Val = RoundUpToPowerOfTwoH<N, (N&(N-1)) == 0>::Val }; 228af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner}; 2296de603071879bdc5d7d663826354c24a9d176469Chris Lattner 230c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 231252968a76f4b34aa26aa33d447d0256a148ad554Bob Wilson/// SmallPtrSet - This class implements a set which is optimized for holding 2320b930852cf1a9899ae82dd6c31b43e754a77dcb0Chris Lattner/// SmallSize or less elements. This internally rounds up SmallSize to the next 2330b930852cf1a9899ae82dd6c31b43e754a77dcb0Chris Lattner/// power of two if it is not already a power of two. See the comments above 2340b930852cf1a9899ae82dd6c31b43e754a77dcb0Chris Lattner/// SmallPtrSetImpl for details of the algorithm. 235c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnertemplate<class PtrType, unsigned SmallSize> 236c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerclass SmallPtrSet : public SmallPtrSetImpl { 237af3056c97e56106af7c3b9a5c856d1dc1d21e358Chris Lattner // Make sure that SmallSize is a power of two, round up if not. 238a71f0e1f2a7d6d2f030f147d6d426e5bb3b56328Duncan Sands enum { SmallSizePowTwo = RoundUpToPowerOfTwo<SmallSize>::Val }; 2392a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands /// SmallStorage - Fixed size storage used in 'small mode'. The extra element 2402a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands /// ensures that the end iterator actually points to valid memory. 2412a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands const void *SmallStorage[SmallSizePowTwo+1]; 2428ee1b5e916249d1a64ad8cf99b08a0e160f9d052Chris Lattner typedef PointerLikeTypeTraits<PtrType> PtrTraits; 243c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattnerpublic: 2442a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands SmallPtrSet() : SmallPtrSetImpl(SmallStorage, SmallSizePowTwo) {} 2452a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands SmallPtrSet(const SmallPtrSet &that) : SmallPtrSetImpl(SmallStorage, that) {} 2463a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 247ab8fea5283de0931e1da5dc91b4df2f734ba0206Chris Lattner template<typename It> 2482a8bf425bd0aff1a6406805c095d99089a1dfaaeDuncan Sands SmallPtrSet(It I, It E) : SmallPtrSetImpl(SmallStorage, SmallSizePowTwo) { 249086f18626750482318612a10c3027b946b4e36e4Chris Lattner insert(I, E); 250ab8fea5283de0931e1da5dc91b4df2f734ba0206Chris Lattner } 2513a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 252373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// insert - This returns true if the pointer was new to the set, false if it 253373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// was already in the set. 2546de603071879bdc5d7d663826354c24a9d176469Chris Lattner bool insert(PtrType Ptr) { 2556de603071879bdc5d7d663826354c24a9d176469Chris Lattner return insert_imp(PtrTraits::getAsVoidPointer(Ptr)); 2566de603071879bdc5d7d663826354c24a9d176469Chris Lattner } 2573a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 258373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// erase - If the set contains the specified pointer, remove it and return 259373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// true, otherwise return false. 2606de603071879bdc5d7d663826354c24a9d176469Chris Lattner bool erase(PtrType Ptr) { 2616de603071879bdc5d7d663826354c24a9d176469Chris Lattner return erase_imp(PtrTraits::getAsVoidPointer(Ptr)); 2626de603071879bdc5d7d663826354c24a9d176469Chris Lattner } 2633a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 264373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner /// count - Return true if the specified pointer is in the set. 2656de603071879bdc5d7d663826354c24a9d176469Chris Lattner bool count(PtrType Ptr) const { 2666de603071879bdc5d7d663826354c24a9d176469Chris Lattner return count_imp(PtrTraits::getAsVoidPointer(Ptr)); 2676de603071879bdc5d7d663826354c24a9d176469Chris Lattner } 2683a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 269373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner template <typename IterT> 270373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner void insert(IterT I, IterT E) { 271373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner for (; I != E; ++I) 272373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner insert(*I); 273373a733be031f52cebbbcdb15ab5997d9b5f9f17Chris Lattner } 2743a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 275c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner typedef SmallPtrSetIterator<PtrType> iterator; 276c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner typedef SmallPtrSetIterator<PtrType> const_iterator; 277c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner inline iterator begin() const { 278c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return iterator(CurArray); 279c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 280c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner inline iterator end() const { 281c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner return iterator(CurArray+CurArraySize); 282c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner } 2833a54b3dc87a581c203b18050b4f787b4ca28a12cMisha Brukman 28491f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner // Allow assignment from any smallptrset with the same element type even if it 28591f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner // doesn't have the same smallsize. 2864d6f96d6997738419627ebe13dd6cb9c88a98fd7Owen Anderson const SmallPtrSet<PtrType, SmallSize>& 28795fd3189f84de5953c75d67403e7db9acdd5005dChris Lattner operator=(const SmallPtrSet<PtrType, SmallSize> &RHS) { 28891f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner CopyFrom(RHS); 28991f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner return *this; 29091f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner } 29191f0158d4d1b16b8615126b05582d421cfb14089Chris Lattner 2922945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer /// swap - Swaps the elements of two sets. 2932945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer void swap(SmallPtrSet<PtrType, SmallSize> &RHS) { 2942945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer SmallPtrSetImpl::swap(RHS); 2952945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer } 296c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner}; 297c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 298c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner} 299c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner 3002945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramernamespace std { 3012945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer /// Implement std::swap in terms of SmallPtrSet swap. 3022945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer template<class T, unsigned N> 3032945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer inline void swap(llvm::SmallPtrSet<T, N> &LHS, llvm::SmallPtrSet<T, N> &RHS) { 3042945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer LHS.swap(RHS); 3052945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer } 3062945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer} 3072945a32ffd0bf079de1b23db12bc8a0de596a167Benjamin Kramer 308c95dc987e9e369c1c63819dbc4f76ab9b913772cChris Lattner#endif 309