1 //===-- Attributes.cpp - Implement AttributesList -------------------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file implements the AttributesList class and Attribute utilities. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Attributes.h" 15 #include "llvm/Type.h" 16 #include "llvm/ADT/StringExtras.h" 17 #include "llvm/ADT/FoldingSet.h" 18 #include "llvm/Support/Atomic.h" 19 #include "llvm/Support/Mutex.h" 20 #include "llvm/Support/Debug.h" 21 #include "llvm/Support/ManagedStatic.h" 22 #include "llvm/Support/raw_ostream.h" 23 using namespace llvm; 24 25 //===----------------------------------------------------------------------===// 26 // Attribute Function Definitions 27 //===----------------------------------------------------------------------===// 28 29 std::string Attribute::getAsString(Attributes Attrs) { 30 std::string Result; 31 if (Attrs & Attribute::ZExt) 32 Result += "zeroext "; 33 if (Attrs & Attribute::SExt) 34 Result += "signext "; 35 if (Attrs & Attribute::NoReturn) 36 Result += "noreturn "; 37 if (Attrs & Attribute::NoUnwind) 38 Result += "nounwind "; 39 if (Attrs & Attribute::UWTable) 40 Result += "uwtable "; 41 if (Attrs & Attribute::ReturnsTwice) 42 Result += "returns_twice "; 43 if (Attrs & Attribute::InReg) 44 Result += "inreg "; 45 if (Attrs & Attribute::NoAlias) 46 Result += "noalias "; 47 if (Attrs & Attribute::NoCapture) 48 Result += "nocapture "; 49 if (Attrs & Attribute::StructRet) 50 Result += "sret "; 51 if (Attrs & Attribute::ByVal) 52 Result += "byval "; 53 if (Attrs & Attribute::Nest) 54 Result += "nest "; 55 if (Attrs & Attribute::ReadNone) 56 Result += "readnone "; 57 if (Attrs & Attribute::ReadOnly) 58 Result += "readonly "; 59 if (Attrs & Attribute::OptimizeForSize) 60 Result += "optsize "; 61 if (Attrs & Attribute::NoInline) 62 Result += "noinline "; 63 if (Attrs & Attribute::InlineHint) 64 Result += "inlinehint "; 65 if (Attrs & Attribute::AlwaysInline) 66 Result += "alwaysinline "; 67 if (Attrs & Attribute::StackProtect) 68 Result += "ssp "; 69 if (Attrs & Attribute::StackProtectReq) 70 Result += "sspreq "; 71 if (Attrs & Attribute::NoRedZone) 72 Result += "noredzone "; 73 if (Attrs & Attribute::NoImplicitFloat) 74 Result += "noimplicitfloat "; 75 if (Attrs & Attribute::Naked) 76 Result += "naked "; 77 if (Attrs & Attribute::NonLazyBind) 78 Result += "nonlazybind "; 79 if (Attrs & Attribute::AddressSafety) 80 Result += "address_safety "; 81 if (Attrs & Attribute::StackAlignment) { 82 Result += "alignstack("; 83 Result += utostr(Attribute::getStackAlignmentFromAttrs(Attrs)); 84 Result += ") "; 85 } 86 if (Attrs & Attribute::Alignment) { 87 Result += "align "; 88 Result += utostr(Attribute::getAlignmentFromAttrs(Attrs)); 89 Result += " "; 90 } 91 // Trim the trailing space. 92 assert(!Result.empty() && "Unknown attribute!"); 93 Result.erase(Result.end()-1); 94 return Result; 95 } 96 97 Attributes Attribute::typeIncompatible(Type *Ty) { 98 Attributes Incompatible = None; 99 100 if (!Ty->isIntegerTy()) 101 // Attributes that only apply to integers. 102 Incompatible |= SExt | ZExt; 103 104 if (!Ty->isPointerTy()) 105 // Attributes that only apply to pointers. 106 Incompatible |= ByVal | Nest | NoAlias | StructRet | NoCapture; 107 108 return Incompatible; 109 } 110 111 //===----------------------------------------------------------------------===// 112 // AttributeListImpl Definition 113 //===----------------------------------------------------------------------===// 114 115 namespace llvm { 116 class AttributeListImpl; 117 } 118 119 static ManagedStatic<FoldingSet<AttributeListImpl> > AttributesLists; 120 121 namespace llvm { 122 static ManagedStatic<sys::SmartMutex<true> > ALMutex; 123 124 class AttributeListImpl : public FoldingSetNode { 125 sys::cas_flag RefCount; 126 127 // AttributesList is uniqued, these should not be publicly available. 128 void operator=(const AttributeListImpl &); // Do not implement 129 AttributeListImpl(const AttributeListImpl &); // Do not implement 130 ~AttributeListImpl(); // Private implementation 131 public: 132 SmallVector<AttributeWithIndex, 4> Attrs; 133 134 AttributeListImpl(const AttributeWithIndex *Attr, unsigned NumAttrs) 135 : Attrs(Attr, Attr+NumAttrs) { 136 RefCount = 0; 137 } 138 139 void AddRef() { 140 sys::SmartScopedLock<true> Lock(*ALMutex); 141 ++RefCount; 142 } 143 void DropRef() { 144 sys::SmartScopedLock<true> Lock(*ALMutex); 145 if (!AttributesLists.isConstructed()) 146 return; 147 sys::cas_flag new_val = --RefCount; 148 if (new_val == 0) 149 delete this; 150 } 151 152 void Profile(FoldingSetNodeID &ID) const { 153 Profile(ID, Attrs.data(), Attrs.size()); 154 } 155 static void Profile(FoldingSetNodeID &ID, const AttributeWithIndex *Attr, 156 unsigned NumAttrs) { 157 for (unsigned i = 0; i != NumAttrs; ++i) { 158 ID.AddInteger(Attr[i].Attrs.Raw()); 159 ID.AddInteger(Attr[i].Index); 160 } 161 } 162 }; 163 } 164 165 AttributeListImpl::~AttributeListImpl() { 166 // NOTE: Lock must be acquired by caller. 167 AttributesLists->RemoveNode(this); 168 } 169 170 171 AttrListPtr AttrListPtr::get(const AttributeWithIndex *Attrs, unsigned NumAttrs) { 172 // If there are no attributes then return a null AttributesList pointer. 173 if (NumAttrs == 0) 174 return AttrListPtr(); 175 176 #ifndef NDEBUG 177 for (unsigned i = 0; i != NumAttrs; ++i) { 178 assert(Attrs[i].Attrs != Attribute::None && 179 "Pointless attribute!"); 180 assert((!i || Attrs[i-1].Index < Attrs[i].Index) && 181 "Misordered AttributesList!"); 182 } 183 #endif 184 185 // Otherwise, build a key to look up the existing attributes. 186 FoldingSetNodeID ID; 187 AttributeListImpl::Profile(ID, Attrs, NumAttrs); 188 void *InsertPos; 189 190 sys::SmartScopedLock<true> Lock(*ALMutex); 191 192 AttributeListImpl *PAL = 193 AttributesLists->FindNodeOrInsertPos(ID, InsertPos); 194 195 // If we didn't find any existing attributes of the same shape then 196 // create a new one and insert it. 197 if (!PAL) { 198 PAL = new AttributeListImpl(Attrs, NumAttrs); 199 AttributesLists->InsertNode(PAL, InsertPos); 200 } 201 202 // Return the AttributesList that we found or created. 203 return AttrListPtr(PAL); 204 } 205 206 207 //===----------------------------------------------------------------------===// 208 // AttrListPtr Method Implementations 209 //===----------------------------------------------------------------------===// 210 211 AttrListPtr::AttrListPtr(AttributeListImpl *LI) : AttrList(LI) { 212 if (LI) LI->AddRef(); 213 } 214 215 AttrListPtr::AttrListPtr(const AttrListPtr &P) : AttrList(P.AttrList) { 216 if (AttrList) AttrList->AddRef(); 217 } 218 219 const AttrListPtr &AttrListPtr::operator=(const AttrListPtr &RHS) { 220 sys::SmartScopedLock<true> Lock(*ALMutex); 221 if (AttrList == RHS.AttrList) return *this; 222 if (AttrList) AttrList->DropRef(); 223 AttrList = RHS.AttrList; 224 if (AttrList) AttrList->AddRef(); 225 return *this; 226 } 227 228 AttrListPtr::~AttrListPtr() { 229 if (AttrList) AttrList->DropRef(); 230 } 231 232 /// getNumSlots - Return the number of slots used in this attribute list. 233 /// This is the number of arguments that have an attribute set on them 234 /// (including the function itself). 235 unsigned AttrListPtr::getNumSlots() const { 236 return AttrList ? AttrList->Attrs.size() : 0; 237 } 238 239 /// getSlot - Return the AttributeWithIndex at the specified slot. This 240 /// holds a number plus a set of attributes. 241 const AttributeWithIndex &AttrListPtr::getSlot(unsigned Slot) const { 242 assert(AttrList && Slot < AttrList->Attrs.size() && "Slot # out of range!"); 243 return AttrList->Attrs[Slot]; 244 } 245 246 247 /// getAttributes - The attributes for the specified index are 248 /// returned. Attributes for the result are denoted with Idx = 0. 249 /// Function notes are denoted with idx = ~0. 250 Attributes AttrListPtr::getAttributes(unsigned Idx) const { 251 if (AttrList == 0) return Attribute::None; 252 253 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs; 254 for (unsigned i = 0, e = Attrs.size(); i != e && Attrs[i].Index <= Idx; ++i) 255 if (Attrs[i].Index == Idx) 256 return Attrs[i].Attrs; 257 return Attribute::None; 258 } 259 260 /// hasAttrSomewhere - Return true if the specified attribute is set for at 261 /// least one parameter or for the return value. 262 bool AttrListPtr::hasAttrSomewhere(Attributes Attr) const { 263 if (AttrList == 0) return false; 264 265 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs; 266 for (unsigned i = 0, e = Attrs.size(); i != e; ++i) 267 if (Attrs[i].Attrs & Attr) 268 return true; 269 return false; 270 } 271 272 273 AttrListPtr AttrListPtr::addAttr(unsigned Idx, Attributes Attrs) const { 274 Attributes OldAttrs = getAttributes(Idx); 275 #ifndef NDEBUG 276 // FIXME it is not obvious how this should work for alignment. 277 // For now, say we can't change a known alignment. 278 Attributes OldAlign = OldAttrs & Attribute::Alignment; 279 Attributes NewAlign = Attrs & Attribute::Alignment; 280 assert((!OldAlign || !NewAlign || OldAlign == NewAlign) && 281 "Attempt to change alignment!"); 282 #endif 283 284 Attributes NewAttrs = OldAttrs | Attrs; 285 if (NewAttrs == OldAttrs) 286 return *this; 287 288 SmallVector<AttributeWithIndex, 8> NewAttrList; 289 if (AttrList == 0) 290 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs)); 291 else { 292 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs; 293 unsigned i = 0, e = OldAttrList.size(); 294 // Copy attributes for arguments before this one. 295 for (; i != e && OldAttrList[i].Index < Idx; ++i) 296 NewAttrList.push_back(OldAttrList[i]); 297 298 // If there are attributes already at this index, merge them in. 299 if (i != e && OldAttrList[i].Index == Idx) { 300 Attrs |= OldAttrList[i].Attrs; 301 ++i; 302 } 303 304 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs)); 305 306 // Copy attributes for arguments after this one. 307 NewAttrList.insert(NewAttrList.end(), 308 OldAttrList.begin()+i, OldAttrList.end()); 309 } 310 311 return get(NewAttrList.data(), NewAttrList.size()); 312 } 313 314 AttrListPtr AttrListPtr::removeAttr(unsigned Idx, Attributes Attrs) const { 315 #ifndef NDEBUG 316 // FIXME it is not obvious how this should work for alignment. 317 // For now, say we can't pass in alignment, which no current use does. 318 assert(!(Attrs & Attribute::Alignment) && "Attempt to exclude alignment!"); 319 #endif 320 if (AttrList == 0) return AttrListPtr(); 321 322 Attributes OldAttrs = getAttributes(Idx); 323 Attributes NewAttrs = OldAttrs & ~Attrs; 324 if (NewAttrs == OldAttrs) 325 return *this; 326 327 SmallVector<AttributeWithIndex, 8> NewAttrList; 328 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs; 329 unsigned i = 0, e = OldAttrList.size(); 330 331 // Copy attributes for arguments before this one. 332 for (; i != e && OldAttrList[i].Index < Idx; ++i) 333 NewAttrList.push_back(OldAttrList[i]); 334 335 // If there are attributes already at this index, merge them in. 336 assert(OldAttrList[i].Index == Idx && "Attribute isn't set?"); 337 Attrs = OldAttrList[i].Attrs & ~Attrs; 338 ++i; 339 if (Attrs) // If any attributes left for this parameter, add them. 340 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs)); 341 342 // Copy attributes for arguments after this one. 343 NewAttrList.insert(NewAttrList.end(), 344 OldAttrList.begin()+i, OldAttrList.end()); 345 346 return get(NewAttrList.data(), NewAttrList.size()); 347 } 348 349 void AttrListPtr::dump() const { 350 dbgs() << "PAL[ "; 351 for (unsigned i = 0; i < getNumSlots(); ++i) { 352 const AttributeWithIndex &PAWI = getSlot(i); 353 dbgs() << "{" << PAWI.Index << "," << PAWI.Attrs << "} "; 354 } 355 356 dbgs() << "]\n"; 357 } 358
