ResolveInfo.cpp revision 22add6ff3426df1a85089fe6a6e1597ee3b6f300
1//===- ResolveInfo.cpp ----------------------------------------------------===// 2// 3// The MCLinker Project 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9#include <mcld/LD/ResolveInfo.h> 10#include <cstdlib> 11#include <cstring> 12 13using namespace mcld; 14 15/// g_NullResolveInfo - a pointer to Null ResolveInfo. 16static ResolveInfo* g_NullResolveInfo = NULL; 17 18//===----------------------------------------------------------------------===// 19// ResolveInfo 20//===----------------------------------------------------------------------===// 21ResolveInfo::ResolveInfo() 22 : m_Size(0), m_BitField(0) { 23 m_Ptr.sym_ptr = 0; 24} 25 26ResolveInfo::~ResolveInfo() 27{ 28} 29 30void ResolveInfo::override(const ResolveInfo& pFrom) 31{ 32 m_Size = pFrom.m_Size; 33 overrideAttributes(pFrom); 34 overrideVisibility(pFrom); 35} 36 37void ResolveInfo::overrideAttributes(const ResolveInfo& pFrom) 38{ 39 m_BitField &= ~RESOLVE_MASK; 40 m_BitField |= (pFrom.m_BitField & RESOLVE_MASK); 41} 42 43/// overrideVisibility - override the visibility 44/// always use the most strict visibility 45void ResolveInfo::overrideVisibility(const ResolveInfo& pFrom) 46{ 47 // Reference: Google gold linker: resolve.cc 48 // 49 // The rule for combining visibility is that we always choose the 50 // most constrained visibility. In order of increasing constraint, 51 // visibility goes PROTECTED, HIDDEN, INTERNAL. This is the reverse 52 // of the numeric values, so the effect is that we always want the 53 // smallest non-zero value. 54 // 55 // enum { 56 // STV_DEFAULT = 0, 57 // STV_INTERNAL = 1, 58 // STV_HIDDEN = 2, 59 // STV_PROTECTED = 3 60 // }; 61 62 Visibility from_vis = pFrom.visibility(); 63 Visibility cur_vis = visibility(); 64 if (0 != from_vis ) { 65 if (0 == cur_vis) 66 setVisibility(from_vis); 67 else if (cur_vis > from_vis) 68 setVisibility(from_vis); 69 } 70} 71 72void ResolveInfo::setRegular() 73{ 74 m_BitField &= (~dynamic_flag); 75} 76 77void ResolveInfo::setDynamic() 78{ 79 m_BitField |= dynamic_flag; 80} 81 82void ResolveInfo::setSource(bool pIsDyn) 83{ 84 if (pIsDyn) 85 m_BitField |= dynamic_flag; 86 else 87 m_BitField &= (~dynamic_flag); 88} 89 90void ResolveInfo::setType(uint32_t pType) 91{ 92 m_BitField &= ~TYPE_MASK; 93 m_BitField |= ((pType << TYPE_OFFSET) & TYPE_MASK); 94} 95 96void ResolveInfo::setDesc(uint32_t pDesc) 97{ 98 m_BitField &= ~DESC_MASK; 99 m_BitField |= ((pDesc << DESC_OFFSET) & DESC_MASK); 100} 101 102void ResolveInfo::setBinding(uint32_t pBinding) 103{ 104 m_BitField &= ~BINDING_MASK; 105 if (pBinding == Local || pBinding == Absolute) 106 m_BitField |= local_flag; 107 if (pBinding == Weak || pBinding == Absolute) 108 m_BitField |= weak_flag; 109} 110 111void ResolveInfo::setReserved(uint32_t pReserved) 112{ 113 m_BitField &= ~RESERVED_MASK; 114 m_BitField |= ((pReserved << RESERVED_OFFSET) & RESERVED_MASK); 115} 116 117void ResolveInfo::setOther(uint32_t pOther) 118{ 119 setVisibility(static_cast<ResolveInfo::Visibility>(pOther & 0x3)); 120} 121 122void ResolveInfo::setVisibility(ResolveInfo::Visibility pVisibility) 123{ 124 m_BitField &= ~VISIBILITY_MASK; 125 m_BitField |= pVisibility << VISIBILITY_OFFSET; 126} 127 128void ResolveInfo::setIsSymbol(bool pIsSymbol) 129{ 130 if (pIsSymbol) 131 m_BitField |= symbol_flag; 132 else 133 m_BitField &= ~symbol_flag; 134} 135 136bool ResolveInfo::isNull() const 137{ 138 return (this == Null()); 139} 140 141bool ResolveInfo::isDyn() const 142{ 143 return (dynamic_flag == (m_BitField & DYN_MASK)); 144} 145 146bool ResolveInfo::isUndef() const 147{ 148 return (undefine_flag == (m_BitField & DESC_MASK)); 149} 150 151bool ResolveInfo::isDefine() const 152{ 153 return (define_flag == (m_BitField & DESC_MASK)); 154} 155 156bool ResolveInfo::isCommon() const 157{ 158 return (common_flag == (m_BitField & DESC_MASK)); 159} 160 161bool ResolveInfo::isIndirect() const 162{ 163 return (indirect_flag == (m_BitField & DESC_MASK)); 164} 165 166// isGlobal - [L,W] == [0, 0] 167bool ResolveInfo::isGlobal() const 168{ 169 return (global_flag == (m_BitField & BINDING_MASK)); 170} 171 172// isWeak - [L,W] == [0, 1] 173bool ResolveInfo::isWeak() const 174{ 175 return (weak_flag == (m_BitField & BINDING_MASK)); 176} 177 178// isLocal - [L,W] == [1, 0] 179bool ResolveInfo::isLocal() const 180{ 181 return (local_flag == (m_BitField & BINDING_MASK)); 182} 183 184// isAbsolute - [L,W] == [1, 1] 185bool ResolveInfo::isAbsolute() const 186{ 187 return (absolute_flag == (m_BitField & BINDING_MASK)); 188} 189 190bool ResolveInfo::isSymbol() const 191{ 192 return (symbol_flag == (m_BitField & SYMBOL_MASK)); 193} 194 195bool ResolveInfo::isString() const 196{ 197 return (string_flag == (m_BitField & SYMBOL_MASK)); 198} 199 200uint32_t ResolveInfo::type() const 201{ 202 return (m_BitField & TYPE_MASK) >> TYPE_OFFSET; 203} 204 205uint32_t ResolveInfo::desc() const 206{ 207 return (m_BitField & DESC_MASK) >> DESC_OFFSET; 208} 209 210uint32_t ResolveInfo::binding() const 211{ 212 if (m_BitField & LOCAL_MASK) { 213 if (m_BitField & GLOBAL_MASK) { 214 return ResolveInfo::Absolute; 215 } 216 return ResolveInfo::Local; 217 } 218 return m_BitField & GLOBAL_MASK; 219} 220 221uint32_t ResolveInfo::reserved() const 222{ 223 return (m_BitField & RESERVED_MASK) >> RESERVED_OFFSET; 224} 225 226ResolveInfo::Visibility ResolveInfo::visibility() const 227{ 228 return static_cast<ResolveInfo::Visibility>((m_BitField & VISIBILITY_MASK) >> VISIBILITY_OFFSET); 229} 230 231bool ResolveInfo::compare(const ResolveInfo::key_type& pKey) 232{ 233 size_t length = nameSize(); 234 if (length != pKey.size()) 235 return false; 236 return (0 == std::memcmp(m_Name, pKey.data(), length)); 237} 238 239//===----------------------------------------------------------------------===// 240// ResolveInfo Factory Methods 241//===----------------------------------------------------------------------===// 242ResolveInfo* ResolveInfo::Create(const ResolveInfo::key_type& pKey) 243{ 244 ResolveInfo* result = static_cast<ResolveInfo*>( 245 malloc(sizeof(ResolveInfo)+pKey.size()+1)); 246 if (NULL == result) 247 return NULL; 248 249 new (result) ResolveInfo(); 250 std::memcpy(result->m_Name, pKey.data(), pKey.size()); 251 result->m_Name[pKey.size()] = '\0'; 252 result->m_BitField &= ~ResolveInfo::RESOLVE_MASK; 253 result->m_BitField |= (pKey.size() << ResolveInfo::NAME_LENGTH_OFFSET); 254 return result; 255} 256 257void ResolveInfo::Destroy(ResolveInfo*& pInfo) 258{ 259 if (pInfo->isNull()) 260 return; 261 262 if (NULL != pInfo) { 263 pInfo->~ResolveInfo(); 264 free(pInfo); 265 } 266 267 pInfo = NULL; 268} 269 270ResolveInfo* ResolveInfo::Null() 271{ 272 if (NULL == g_NullResolveInfo) { 273 g_NullResolveInfo = static_cast<ResolveInfo*>( 274 malloc(sizeof(ResolveInfo) + 1)); 275 new (g_NullResolveInfo) ResolveInfo(); 276 g_NullResolveInfo->m_Name[0] = '\0'; 277 g_NullResolveInfo->m_BitField = 0x0; 278 } 279 return g_NullResolveInfo; 280} 281 282