John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 1 | //===-- CGCleanup.h - Classes for cleanups IR generation --------*- C++ -*-===// |
| 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 | // These classes support the generation of LLVM IR for cleanups. |
| 11 | // |
| 12 | //===----------------------------------------------------------------------===// |
| 13 | |
Stephen Hines | 176edba | 2014-12-01 14:53:08 -0800 | [diff] [blame] | 14 | #ifndef LLVM_CLANG_LIB_CODEGEN_CGCLEANUP_H |
| 15 | #define LLVM_CLANG_LIB_CODEGEN_CGCLEANUP_H |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 16 | |
Reid Kleckner | 43a75fc | 2013-06-19 17:07:50 +0000 | [diff] [blame] | 17 | #include "EHScopeStack.h" |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 18 | |
| 19 | #include "Address.h" |
Reid Kleckner | 6fe91e4 | 2013-06-09 16:45:02 +0000 | [diff] [blame] | 20 | #include "llvm/ADT/SmallPtrSet.h" |
| 21 | #include "llvm/ADT/SmallVector.h" |
Reid Kleckner | 43a75fc | 2013-06-19 17:07:50 +0000 | [diff] [blame] | 22 | |
| 23 | namespace llvm { |
| 24 | class BasicBlock; |
| 25 | class Value; |
| 26 | class ConstantInt; |
| 27 | class AllocaInst; |
| 28 | } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 29 | |
| 30 | namespace clang { |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 31 | class FunctionDecl; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 32 | namespace CodeGen { |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 33 | class CodeGenModule; |
| 34 | class CodeGenFunction; |
| 35 | |
| 36 | /// The MS C++ ABI needs a pointer to RTTI data plus some flags to describe the |
| 37 | /// type of a catch handler, so we use this wrapper. |
| 38 | struct CatchTypeInfo { |
| 39 | llvm::Constant *RTTI; |
| 40 | unsigned Flags; |
| 41 | }; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 42 | |
| 43 | /// A protected scope for zero-cost EH handling. |
| 44 | class EHScope { |
| 45 | llvm::BasicBlock *CachedLandingPad; |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 46 | llvm::BasicBlock *CachedEHDispatchBlock; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 47 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 48 | EHScopeStack::stable_iterator EnclosingEHScope; |
| 49 | |
| 50 | class CommonBitFields { |
| 51 | friend class EHScope; |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 52 | unsigned Kind : 3; |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 53 | }; |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 54 | enum { NumCommonBits = 3 }; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 55 | |
| 56 | protected: |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 57 | class CatchBitFields { |
| 58 | friend class EHCatchScope; |
| 59 | unsigned : NumCommonBits; |
| 60 | |
| 61 | unsigned NumHandlers : 32 - NumCommonBits; |
| 62 | }; |
| 63 | |
| 64 | class CleanupBitFields { |
| 65 | friend class EHCleanupScope; |
| 66 | unsigned : NumCommonBits; |
| 67 | |
| 68 | /// Whether this cleanup needs to be run along normal edges. |
| 69 | unsigned IsNormalCleanup : 1; |
| 70 | |
| 71 | /// Whether this cleanup needs to be run along exception edges. |
| 72 | unsigned IsEHCleanup : 1; |
| 73 | |
| 74 | /// Whether this cleanup is currently active. |
| 75 | unsigned IsActive : 1; |
| 76 | |
Pirama Arumuga Nainar | b6d6993 | 2015-07-01 12:25:36 -0700 | [diff] [blame] | 77 | /// Whether this cleanup is a lifetime marker |
| 78 | unsigned IsLifetimeMarker : 1; |
| 79 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 80 | /// Whether the normal cleanup should test the activation flag. |
| 81 | unsigned TestFlagInNormalCleanup : 1; |
| 82 | |
| 83 | /// Whether the EH cleanup should test the activation flag. |
| 84 | unsigned TestFlagInEHCleanup : 1; |
| 85 | |
| 86 | /// The amount of extra storage needed by the Cleanup. |
| 87 | /// Always a multiple of the scope-stack alignment. |
| 88 | unsigned CleanupSize : 12; |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 89 | }; |
| 90 | |
| 91 | class FilterBitFields { |
| 92 | friend class EHFilterScope; |
| 93 | unsigned : NumCommonBits; |
| 94 | |
| 95 | unsigned NumFilters : 32 - NumCommonBits; |
| 96 | }; |
| 97 | |
| 98 | union { |
| 99 | CommonBitFields CommonBits; |
| 100 | CatchBitFields CatchBits; |
| 101 | CleanupBitFields CleanupBits; |
| 102 | FilterBitFields FilterBits; |
| 103 | }; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 104 | |
| 105 | public: |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 106 | enum Kind { Cleanup, Catch, Terminate, Filter, PadEnd }; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 107 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 108 | EHScope(Kind kind, EHScopeStack::stable_iterator enclosingEHScope) |
Stephen Hines | 6bcf27b | 2014-05-29 04:14:42 -0700 | [diff] [blame] | 109 | : CachedLandingPad(nullptr), CachedEHDispatchBlock(nullptr), |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 110 | EnclosingEHScope(enclosingEHScope) { |
| 111 | CommonBits.Kind = kind; |
| 112 | } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 113 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 114 | Kind getKind() const { return static_cast<Kind>(CommonBits.Kind); } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 115 | |
| 116 | llvm::BasicBlock *getCachedLandingPad() const { |
| 117 | return CachedLandingPad; |
| 118 | } |
| 119 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 120 | void setCachedLandingPad(llvm::BasicBlock *block) { |
| 121 | CachedLandingPad = block; |
| 122 | } |
| 123 | |
| 124 | llvm::BasicBlock *getCachedEHDispatchBlock() const { |
| 125 | return CachedEHDispatchBlock; |
| 126 | } |
| 127 | |
| 128 | void setCachedEHDispatchBlock(llvm::BasicBlock *block) { |
| 129 | CachedEHDispatchBlock = block; |
| 130 | } |
| 131 | |
| 132 | bool hasEHBranches() const { |
| 133 | if (llvm::BasicBlock *block = getCachedEHDispatchBlock()) |
| 134 | return !block->use_empty(); |
| 135 | return false; |
| 136 | } |
| 137 | |
| 138 | EHScopeStack::stable_iterator getEnclosingEHScope() const { |
| 139 | return EnclosingEHScope; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 140 | } |
| 141 | }; |
| 142 | |
| 143 | /// A scope which attempts to handle some, possibly all, types of |
| 144 | /// exceptions. |
| 145 | /// |
James Dennett | 2ee5ba3 | 2012-06-15 22:10:14 +0000 | [diff] [blame] | 146 | /// Objective C \@finally blocks are represented using a cleanup scope |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 147 | /// after the catch scope. |
| 148 | class EHCatchScope : public EHScope { |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 149 | // In effect, we have a flexible array member |
| 150 | // Handler Handlers[0]; |
| 151 | // But that's only standard in C99, not C++, so we have to do |
| 152 | // annoying pointer arithmetic instead. |
| 153 | |
| 154 | public: |
| 155 | struct Handler { |
| 156 | /// A type info value, or null (C++ null, not an LLVM null pointer) |
| 157 | /// for a catch-all. |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 158 | CatchTypeInfo Type; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 159 | |
| 160 | /// The catch handler for this type. |
| 161 | llvm::BasicBlock *Block; |
| 162 | |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 163 | bool isCatchAll() const { return Type.RTTI == nullptr; } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 164 | }; |
| 165 | |
| 166 | private: |
| 167 | friend class EHScopeStack; |
| 168 | |
| 169 | Handler *getHandlers() { |
| 170 | return reinterpret_cast<Handler*>(this+1); |
| 171 | } |
| 172 | |
| 173 | const Handler *getHandlers() const { |
| 174 | return reinterpret_cast<const Handler*>(this+1); |
| 175 | } |
| 176 | |
| 177 | public: |
| 178 | static size_t getSizeForNumHandlers(unsigned N) { |
| 179 | return sizeof(EHCatchScope) + N * sizeof(Handler); |
| 180 | } |
| 181 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 182 | EHCatchScope(unsigned numHandlers, |
| 183 | EHScopeStack::stable_iterator enclosingEHScope) |
| 184 | : EHScope(Catch, enclosingEHScope) { |
| 185 | CatchBits.NumHandlers = numHandlers; |
Pirama Arumuga Nainar | 4967a71 | 2016-09-19 22:19:55 -0700 | [diff] [blame^] | 186 | assert(CatchBits.NumHandlers == numHandlers && "NumHandlers overflow?"); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 187 | } |
| 188 | |
| 189 | unsigned getNumHandlers() const { |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 190 | return CatchBits.NumHandlers; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 191 | } |
| 192 | |
| 193 | void setCatchAllHandler(unsigned I, llvm::BasicBlock *Block) { |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 194 | setHandler(I, CatchTypeInfo{nullptr, 0}, Block); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 195 | } |
| 196 | |
Stephen Hines | c568f1e | 2014-07-21 00:47:37 -0700 | [diff] [blame] | 197 | void setHandler(unsigned I, llvm::Constant *Type, llvm::BasicBlock *Block) { |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 198 | assert(I < getNumHandlers()); |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 199 | getHandlers()[I].Type = CatchTypeInfo{Type, 0}; |
| 200 | getHandlers()[I].Block = Block; |
| 201 | } |
| 202 | |
| 203 | void setHandler(unsigned I, CatchTypeInfo Type, llvm::BasicBlock *Block) { |
| 204 | assert(I < getNumHandlers()); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 205 | getHandlers()[I].Type = Type; |
| 206 | getHandlers()[I].Block = Block; |
| 207 | } |
| 208 | |
| 209 | const Handler &getHandler(unsigned I) const { |
| 210 | assert(I < getNumHandlers()); |
| 211 | return getHandlers()[I]; |
| 212 | } |
| 213 | |
Stephen Hines | 651f13c | 2014-04-23 16:59:28 -0700 | [diff] [blame] | 214 | // Clear all handler blocks. |
| 215 | // FIXME: it's better to always call clearHandlerBlocks in DTOR and have a |
| 216 | // 'takeHandler' or some such function which removes ownership from the |
| 217 | // EHCatchScope object if the handlers should live longer than EHCatchScope. |
| 218 | void clearHandlerBlocks() { |
| 219 | for (unsigned I = 0, N = getNumHandlers(); I != N; ++I) |
| 220 | delete getHandler(I).Block; |
| 221 | } |
| 222 | |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 223 | typedef const Handler *iterator; |
| 224 | iterator begin() const { return getHandlers(); } |
| 225 | iterator end() const { return getHandlers() + getNumHandlers(); } |
| 226 | |
| 227 | static bool classof(const EHScope *Scope) { |
| 228 | return Scope->getKind() == Catch; |
| 229 | } |
| 230 | }; |
| 231 | |
| 232 | /// A cleanup scope which generates the cleanup blocks lazily. |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 233 | class LLVM_ALIGNAS(/*alignof(uint64_t)*/ 8) EHCleanupScope : public EHScope { |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 234 | /// The nearest normal cleanup scope enclosing this one. |
| 235 | EHScopeStack::stable_iterator EnclosingNormal; |
| 236 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 237 | /// The nearest EH scope enclosing this one. |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 238 | EHScopeStack::stable_iterator EnclosingEH; |
| 239 | |
| 240 | /// The dual entry/exit block along the normal edge. This is lazily |
| 241 | /// created if needed before the cleanup is popped. |
| 242 | llvm::BasicBlock *NormalBlock; |
| 243 | |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 244 | /// An optional i1 variable indicating whether this cleanup has been |
| 245 | /// activated yet. |
| 246 | llvm::AllocaInst *ActiveFlag; |
| 247 | |
| 248 | /// Extra information required for cleanups that have resolved |
| 249 | /// branches through them. This has to be allocated on the side |
| 250 | /// because everything on the cleanup stack has be trivially |
| 251 | /// movable. |
| 252 | struct ExtInfo { |
| 253 | /// The destinations of normal branch-afters and branch-throughs. |
| 254 | llvm::SmallPtrSet<llvm::BasicBlock*, 4> Branches; |
| 255 | |
| 256 | /// Normal branch-afters. |
Chris Lattner | 686775d | 2011-07-20 06:58:45 +0000 | [diff] [blame] | 257 | SmallVector<std::pair<llvm::BasicBlock*,llvm::ConstantInt*>, 4> |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 258 | BranchAfters; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 259 | }; |
| 260 | mutable struct ExtInfo *ExtInfo; |
| 261 | |
Pirama Arumuga Nainar | 4967a71 | 2016-09-19 22:19:55 -0700 | [diff] [blame^] | 262 | /// The number of fixups required by enclosing scopes (not including |
| 263 | /// this one). If this is the top cleanup scope, all the fixups |
| 264 | /// from this index onwards belong to this scope. |
| 265 | unsigned FixupDepth; |
| 266 | |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 267 | struct ExtInfo &getExtInfo() { |
| 268 | if (!ExtInfo) ExtInfo = new struct ExtInfo(); |
| 269 | return *ExtInfo; |
| 270 | } |
| 271 | |
| 272 | const struct ExtInfo &getExtInfo() const { |
| 273 | if (!ExtInfo) ExtInfo = new struct ExtInfo(); |
| 274 | return *ExtInfo; |
| 275 | } |
| 276 | |
| 277 | public: |
| 278 | /// Gets the size required for a lazy cleanup scope with the given |
| 279 | /// cleanup-data requirements. |
| 280 | static size_t getSizeForCleanupSize(size_t Size) { |
| 281 | return sizeof(EHCleanupScope) + Size; |
| 282 | } |
| 283 | |
| 284 | size_t getAllocatedSize() const { |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 285 | return sizeof(EHCleanupScope) + CleanupBits.CleanupSize; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 286 | } |
| 287 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 288 | EHCleanupScope(bool isNormal, bool isEH, bool isActive, |
| 289 | unsigned cleanupSize, unsigned fixupDepth, |
| 290 | EHScopeStack::stable_iterator enclosingNormal, |
| 291 | EHScopeStack::stable_iterator enclosingEH) |
Pirama Arumuga Nainar | 4967a71 | 2016-09-19 22:19:55 -0700 | [diff] [blame^] | 292 | : EHScope(EHScope::Cleanup, enclosingEH), |
| 293 | EnclosingNormal(enclosingNormal), NormalBlock(nullptr), |
| 294 | ActiveFlag(nullptr), ExtInfo(nullptr), FixupDepth(fixupDepth) { |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 295 | CleanupBits.IsNormalCleanup = isNormal; |
| 296 | CleanupBits.IsEHCleanup = isEH; |
| 297 | CleanupBits.IsActive = isActive; |
Pirama Arumuga Nainar | b6d6993 | 2015-07-01 12:25:36 -0700 | [diff] [blame] | 298 | CleanupBits.IsLifetimeMarker = false; |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 299 | CleanupBits.TestFlagInNormalCleanup = false; |
| 300 | CleanupBits.TestFlagInEHCleanup = false; |
| 301 | CleanupBits.CleanupSize = cleanupSize; |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 302 | |
| 303 | assert(CleanupBits.CleanupSize == cleanupSize && "cleanup size overflow"); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 304 | } |
| 305 | |
Stephen Hines | 176edba | 2014-12-01 14:53:08 -0800 | [diff] [blame] | 306 | void Destroy() { |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 307 | delete ExtInfo; |
| 308 | } |
Stephen Hines | 176edba | 2014-12-01 14:53:08 -0800 | [diff] [blame] | 309 | // Objects of EHCleanupScope are not destructed. Use Destroy(). |
Stephen Hines | 0e2c34f | 2015-03-23 12:09:02 -0700 | [diff] [blame] | 310 | ~EHCleanupScope() = delete; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 311 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 312 | bool isNormalCleanup() const { return CleanupBits.IsNormalCleanup; } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 313 | llvm::BasicBlock *getNormalBlock() const { return NormalBlock; } |
| 314 | void setNormalBlock(llvm::BasicBlock *BB) { NormalBlock = BB; } |
| 315 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 316 | bool isEHCleanup() const { return CleanupBits.IsEHCleanup; } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 317 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 318 | bool isActive() const { return CleanupBits.IsActive; } |
| 319 | void setActive(bool A) { CleanupBits.IsActive = A; } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 320 | |
Pirama Arumuga Nainar | b6d6993 | 2015-07-01 12:25:36 -0700 | [diff] [blame] | 321 | bool isLifetimeMarker() const { return CleanupBits.IsLifetimeMarker; } |
| 322 | void setLifetimeMarker() { CleanupBits.IsLifetimeMarker = true; } |
| 323 | |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 324 | bool hasActiveFlag() const { return ActiveFlag != nullptr; } |
| 325 | Address getActiveFlag() const { |
| 326 | return Address(ActiveFlag, CharUnits::One()); |
| 327 | } |
| 328 | void setActiveFlag(Address Var) { |
| 329 | assert(Var.getAlignment().isOne()); |
| 330 | ActiveFlag = cast<llvm::AllocaInst>(Var.getPointer()); |
| 331 | } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 332 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 333 | void setTestFlagInNormalCleanup() { |
| 334 | CleanupBits.TestFlagInNormalCleanup = true; |
| 335 | } |
| 336 | bool shouldTestFlagInNormalCleanup() const { |
| 337 | return CleanupBits.TestFlagInNormalCleanup; |
| 338 | } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 339 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 340 | void setTestFlagInEHCleanup() { |
| 341 | CleanupBits.TestFlagInEHCleanup = true; |
| 342 | } |
| 343 | bool shouldTestFlagInEHCleanup() const { |
| 344 | return CleanupBits.TestFlagInEHCleanup; |
| 345 | } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 346 | |
Pirama Arumuga Nainar | 4967a71 | 2016-09-19 22:19:55 -0700 | [diff] [blame^] | 347 | unsigned getFixupDepth() const { return FixupDepth; } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 348 | EHScopeStack::stable_iterator getEnclosingNormalCleanup() const { |
| 349 | return EnclosingNormal; |
| 350 | } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 351 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 352 | size_t getCleanupSize() const { return CleanupBits.CleanupSize; } |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 353 | void *getCleanupBuffer() { return this + 1; } |
| 354 | |
| 355 | EHScopeStack::Cleanup *getCleanup() { |
| 356 | return reinterpret_cast<EHScopeStack::Cleanup*>(getCleanupBuffer()); |
| 357 | } |
| 358 | |
| 359 | /// True if this cleanup scope has any branch-afters or branch-throughs. |
| 360 | bool hasBranches() const { return ExtInfo && !ExtInfo->Branches.empty(); } |
| 361 | |
| 362 | /// Add a branch-after to this cleanup scope. A branch-after is a |
| 363 | /// branch from a point protected by this (normal) cleanup to a |
| 364 | /// point in the normal cleanup scope immediately containing it. |
| 365 | /// For example, |
| 366 | /// for (;;) { A a; break; } |
| 367 | /// contains a branch-after. |
| 368 | /// |
| 369 | /// Branch-afters each have their own destination out of the |
| 370 | /// cleanup, guaranteed distinct from anything else threaded through |
| 371 | /// it. Therefore branch-afters usually force a switch after the |
| 372 | /// cleanup. |
| 373 | void addBranchAfter(llvm::ConstantInt *Index, |
| 374 | llvm::BasicBlock *Block) { |
| 375 | struct ExtInfo &ExtInfo = getExtInfo(); |
Stephen Hines | 176edba | 2014-12-01 14:53:08 -0800 | [diff] [blame] | 376 | if (ExtInfo.Branches.insert(Block).second) |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 377 | ExtInfo.BranchAfters.push_back(std::make_pair(Block, Index)); |
| 378 | } |
| 379 | |
| 380 | /// Return the number of unique branch-afters on this scope. |
| 381 | unsigned getNumBranchAfters() const { |
| 382 | return ExtInfo ? ExtInfo->BranchAfters.size() : 0; |
| 383 | } |
| 384 | |
| 385 | llvm::BasicBlock *getBranchAfterBlock(unsigned I) const { |
| 386 | assert(I < getNumBranchAfters()); |
| 387 | return ExtInfo->BranchAfters[I].first; |
| 388 | } |
| 389 | |
| 390 | llvm::ConstantInt *getBranchAfterIndex(unsigned I) const { |
| 391 | assert(I < getNumBranchAfters()); |
| 392 | return ExtInfo->BranchAfters[I].second; |
| 393 | } |
| 394 | |
| 395 | /// Add a branch-through to this cleanup scope. A branch-through is |
| 396 | /// a branch from a scope protected by this (normal) cleanup to an |
| 397 | /// enclosing scope other than the immediately-enclosing normal |
| 398 | /// cleanup scope. |
| 399 | /// |
| 400 | /// In the following example, the branch through B's scope is a |
| 401 | /// branch-through, while the branch through A's scope is a |
| 402 | /// branch-after: |
| 403 | /// for (;;) { A a; B b; break; } |
| 404 | /// |
| 405 | /// All branch-throughs have a common destination out of the |
| 406 | /// cleanup, one possibly shared with the fall-through. Therefore |
| 407 | /// branch-throughs usually don't force a switch after the cleanup. |
| 408 | /// |
| 409 | /// \return true if the branch-through was new to this scope |
| 410 | bool addBranchThrough(llvm::BasicBlock *Block) { |
Stephen Hines | 176edba | 2014-12-01 14:53:08 -0800 | [diff] [blame] | 411 | return getExtInfo().Branches.insert(Block).second; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 412 | } |
| 413 | |
| 414 | /// Determines if this cleanup scope has any branch throughs. |
| 415 | bool hasBranchThroughs() const { |
| 416 | if (!ExtInfo) return false; |
| 417 | return (ExtInfo->BranchAfters.size() != ExtInfo->Branches.size()); |
| 418 | } |
| 419 | |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 420 | static bool classof(const EHScope *Scope) { |
| 421 | return (Scope->getKind() == Cleanup); |
| 422 | } |
| 423 | }; |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 424 | // NOTE: there's a bunch of different data classes tacked on after an |
| 425 | // EHCleanupScope. It is asserted (in EHScopeStack::pushCleanup*) that |
| 426 | // they don't require greater alignment than ScopeStackAlignment. So, |
| 427 | // EHCleanupScope ought to have alignment equal to that -- not more |
| 428 | // (would be misaligned by the stack allocator), and not less (would |
| 429 | // break the appended classes). |
| 430 | static_assert(llvm::AlignOf<EHCleanupScope>::Alignment == |
| 431 | EHScopeStack::ScopeStackAlignment, |
| 432 | "EHCleanupScope expected alignment"); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 433 | |
| 434 | /// An exceptions scope which filters exceptions thrown through it. |
| 435 | /// Only exceptions matching the filter types will be permitted to be |
| 436 | /// thrown. |
| 437 | /// |
| 438 | /// This is used to implement C++ exception specifications. |
| 439 | class EHFilterScope : public EHScope { |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 440 | // Essentially ends in a flexible array member: |
| 441 | // llvm::Value *FilterTypes[0]; |
| 442 | |
| 443 | llvm::Value **getFilters() { |
| 444 | return reinterpret_cast<llvm::Value**>(this+1); |
| 445 | } |
| 446 | |
| 447 | llvm::Value * const *getFilters() const { |
| 448 | return reinterpret_cast<llvm::Value* const *>(this+1); |
| 449 | } |
| 450 | |
| 451 | public: |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 452 | EHFilterScope(unsigned numFilters) |
| 453 | : EHScope(Filter, EHScopeStack::stable_end()) { |
| 454 | FilterBits.NumFilters = numFilters; |
Pirama Arumuga Nainar | 4967a71 | 2016-09-19 22:19:55 -0700 | [diff] [blame^] | 455 | assert(FilterBits.NumFilters == numFilters && "NumFilters overflow"); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 456 | } |
| 457 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 458 | static size_t getSizeForNumFilters(unsigned numFilters) { |
| 459 | return sizeof(EHFilterScope) + numFilters * sizeof(llvm::Value*); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 460 | } |
| 461 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 462 | unsigned getNumFilters() const { return FilterBits.NumFilters; } |
| 463 | |
| 464 | void setFilter(unsigned i, llvm::Value *filterValue) { |
| 465 | assert(i < getNumFilters()); |
| 466 | getFilters()[i] = filterValue; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 467 | } |
| 468 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 469 | llvm::Value *getFilter(unsigned i) const { |
| 470 | assert(i < getNumFilters()); |
| 471 | return getFilters()[i]; |
| 472 | } |
| 473 | |
| 474 | static bool classof(const EHScope *scope) { |
| 475 | return scope->getKind() == Filter; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 476 | } |
| 477 | }; |
| 478 | |
| 479 | /// An exceptions scope which calls std::terminate if any exception |
| 480 | /// reaches it. |
| 481 | class EHTerminateScope : public EHScope { |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 482 | public: |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 483 | EHTerminateScope(EHScopeStack::stable_iterator enclosingEHScope) |
| 484 | : EHScope(Terminate, enclosingEHScope) {} |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 485 | static size_t getSize() { return sizeof(EHTerminateScope); } |
| 486 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 487 | static bool classof(const EHScope *scope) { |
| 488 | return scope->getKind() == Terminate; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 489 | } |
| 490 | }; |
| 491 | |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 492 | class EHPadEndScope : public EHScope { |
| 493 | public: |
| 494 | EHPadEndScope(EHScopeStack::stable_iterator enclosingEHScope) |
| 495 | : EHScope(PadEnd, enclosingEHScope) {} |
| 496 | static size_t getSize() { return sizeof(EHPadEndScope); } |
| 497 | |
| 498 | static bool classof(const EHScope *scope) { |
| 499 | return scope->getKind() == PadEnd; |
| 500 | } |
| 501 | }; |
| 502 | |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 503 | /// A non-stable pointer into the scope stack. |
| 504 | class EHScopeStack::iterator { |
| 505 | char *Ptr; |
| 506 | |
| 507 | friend class EHScopeStack; |
| 508 | explicit iterator(char *Ptr) : Ptr(Ptr) {} |
| 509 | |
| 510 | public: |
Stephen Hines | 6bcf27b | 2014-05-29 04:14:42 -0700 | [diff] [blame] | 511 | iterator() : Ptr(nullptr) {} |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 512 | |
| 513 | EHScope *get() const { |
| 514 | return reinterpret_cast<EHScope*>(Ptr); |
| 515 | } |
| 516 | |
| 517 | EHScope *operator->() const { return get(); } |
| 518 | EHScope &operator*() const { return *get(); } |
| 519 | |
| 520 | iterator &operator++() { |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 521 | size_t Size; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 522 | switch (get()->getKind()) { |
| 523 | case EHScope::Catch: |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 524 | Size = EHCatchScope::getSizeForNumHandlers( |
| 525 | static_cast<const EHCatchScope *>(get())->getNumHandlers()); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 526 | break; |
| 527 | |
| 528 | case EHScope::Filter: |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 529 | Size = EHFilterScope::getSizeForNumFilters( |
| 530 | static_cast<const EHFilterScope *>(get())->getNumFilters()); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 531 | break; |
| 532 | |
| 533 | case EHScope::Cleanup: |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 534 | Size = static_cast<const EHCleanupScope *>(get())->getAllocatedSize(); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 535 | break; |
| 536 | |
| 537 | case EHScope::Terminate: |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 538 | Size = EHTerminateScope::getSize(); |
| 539 | break; |
| 540 | |
| 541 | case EHScope::PadEnd: |
| 542 | Size = EHPadEndScope::getSize(); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 543 | break; |
| 544 | } |
Pirama Arumuga Nainar | 4967a71 | 2016-09-19 22:19:55 -0700 | [diff] [blame^] | 545 | Ptr += llvm::alignTo(Size, ScopeStackAlignment); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 546 | return *this; |
| 547 | } |
| 548 | |
| 549 | iterator next() { |
| 550 | iterator copy = *this; |
| 551 | ++copy; |
| 552 | return copy; |
| 553 | } |
| 554 | |
| 555 | iterator operator++(int) { |
| 556 | iterator copy = *this; |
| 557 | operator++(); |
| 558 | return copy; |
| 559 | } |
| 560 | |
| 561 | bool encloses(iterator other) const { return Ptr >= other.Ptr; } |
| 562 | bool strictlyEncloses(iterator other) const { return Ptr > other.Ptr; } |
| 563 | |
| 564 | bool operator==(iterator other) const { return Ptr == other.Ptr; } |
| 565 | bool operator!=(iterator other) const { return Ptr != other.Ptr; } |
| 566 | }; |
| 567 | |
| 568 | inline EHScopeStack::iterator EHScopeStack::begin() const { |
| 569 | return iterator(StartOfData); |
| 570 | } |
| 571 | |
| 572 | inline EHScopeStack::iterator EHScopeStack::end() const { |
| 573 | return iterator(EndOfBuffer); |
| 574 | } |
| 575 | |
| 576 | inline void EHScopeStack::popCatch() { |
| 577 | assert(!empty() && "popping exception stack when not empty"); |
| 578 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 579 | EHCatchScope &scope = cast<EHCatchScope>(*begin()); |
| 580 | InnermostEHScope = scope.getEnclosingEHScope(); |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 581 | deallocate(EHCatchScope::getSizeForNumHandlers(scope.getNumHandlers())); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 582 | } |
| 583 | |
| 584 | inline void EHScopeStack::popTerminate() { |
| 585 | assert(!empty() && "popping exception stack when not empty"); |
| 586 | |
John McCall | 777d6e5 | 2011-08-11 02:22:43 +0000 | [diff] [blame] | 587 | EHTerminateScope &scope = cast<EHTerminateScope>(*begin()); |
| 588 | InnermostEHScope = scope.getEnclosingEHScope(); |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 589 | deallocate(EHTerminateScope::getSize()); |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 590 | } |
| 591 | |
| 592 | inline EHScopeStack::iterator EHScopeStack::find(stable_iterator sp) const { |
| 593 | assert(sp.isValid() && "finding invalid savepoint"); |
| 594 | assert(sp.Size <= stable_begin().Size && "finding savepoint after pop"); |
| 595 | return iterator(EndOfBuffer - sp.Size); |
| 596 | } |
| 597 | |
| 598 | inline EHScopeStack::stable_iterator |
| 599 | EHScopeStack::stabilize(iterator ir) const { |
| 600 | assert(StartOfData <= ir.Ptr && ir.Ptr <= EndOfBuffer); |
| 601 | return stable_iterator(EndOfBuffer - ir.Ptr); |
| 602 | } |
| 603 | |
Pirama Arumuga Nainar | 87d948e | 2016-03-03 15:49:35 -0800 | [diff] [blame] | 604 | /// The exceptions personality for a function. |
| 605 | struct EHPersonality { |
| 606 | const char *PersonalityFn; |
| 607 | |
| 608 | // If this is non-null, this personality requires a non-standard |
| 609 | // function for rethrowing an exception after a catchall cleanup. |
| 610 | // This function must have prototype void(void*). |
| 611 | const char *CatchallRethrowFn; |
| 612 | |
| 613 | static const EHPersonality &get(CodeGenModule &CGM, const FunctionDecl *FD); |
| 614 | static const EHPersonality &get(CodeGenFunction &CGF); |
| 615 | |
| 616 | static const EHPersonality GNU_C; |
| 617 | static const EHPersonality GNU_C_SJLJ; |
| 618 | static const EHPersonality GNU_C_SEH; |
| 619 | static const EHPersonality GNU_ObjC; |
| 620 | static const EHPersonality GNUstep_ObjC; |
| 621 | static const EHPersonality GNU_ObjCXX; |
| 622 | static const EHPersonality NeXT_ObjC; |
| 623 | static const EHPersonality GNU_CPlusPlus; |
| 624 | static const EHPersonality GNU_CPlusPlus_SJLJ; |
| 625 | static const EHPersonality GNU_CPlusPlus_SEH; |
| 626 | static const EHPersonality MSVC_except_handler; |
| 627 | static const EHPersonality MSVC_C_specific_handler; |
| 628 | static const EHPersonality MSVC_CxxFrameHandler3; |
| 629 | |
| 630 | /// Does this personality use landingpads or the family of pad instructions |
| 631 | /// designed to form funclets? |
| 632 | bool usesFuncletPads() const { return isMSVCPersonality(); } |
| 633 | |
| 634 | bool isMSVCPersonality() const { |
| 635 | return this == &MSVC_except_handler || this == &MSVC_C_specific_handler || |
| 636 | this == &MSVC_CxxFrameHandler3; |
| 637 | } |
| 638 | |
| 639 | bool isMSVCXXPersonality() const { return this == &MSVC_CxxFrameHandler3; } |
| 640 | }; |
John McCall | 36f893c | 2011-01-28 11:13:47 +0000 | [diff] [blame] | 641 | } |
| 642 | } |
| 643 | |
| 644 | #endif |