lib/IR/LLVMContextImpl.cpp

   1 //===- LLVMContextImpl.cpp - Implement LLVMContextImpl --------------------===//
   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 opaque LLVMContextImpl.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "LLVMContextImpl.h"
  15 #include "llvm/IR/Module.h"
  16 #include "llvm/IR/OptBisect.h"
  17 #include "llvm/IR/Type.h"
  18 #include "llvm/Support/ManagedStatic.h"
  19 #include <cassert>
  20 #include <utility>
  21
  22 using namespace llvm;
  23
  24 LLVMContextImpl::LLVMContextImpl(LLVMContext &C)
  25   : DiagHandler(llvm::make_unique<DiagnosticHandler>()),
  26     VoidTy(C, Type::VoidTyID),
  27     LabelTy(C, Type::LabelTyID),
  28     HalfTy(C, Type::HalfTyID),
  29     FloatTy(C, Type::FloatTyID),
  30     DoubleTy(C, Type::DoubleTyID),
  31     MetadataTy(C, Type::MetadataTyID),
  32     TokenTy(C, Type::TokenTyID),
  33     X86_FP80Ty(C, Type::X86_FP80TyID),
  34     FP128Ty(C, Type::FP128TyID),
  35     PPC_FP128Ty(C, Type::PPC_FP128TyID),
  36     X86_MMXTy(C, Type::X86_MMXTyID),
  37     Int1Ty(C, 1),
  38     Int8Ty(C, 8),
  39     Int16Ty(C, 16),
  40     Int32Ty(C, 32),
  41     Int64Ty(C, 64),
  42     Int128Ty(C, 128) {}
  43
  44 LLVMContextImpl::~LLVMContextImpl() {
  45   // NOTE: We need to delete the contents of OwnedModules, but Module's dtor
  46   // will call LLVMContextImpl::removeModule, thus invalidating iterators into
  47   // the container. Avoid iterators during this operation:
  48   while (!OwnedModules.empty())
  49     delete *OwnedModules.begin();
  50
  51 #ifndef NDEBUG
  52   // Check for metadata references from leaked Instructions.
  53   for (auto &Pair : InstructionMetadata)
  54     Pair.first->dump();
  55   assert(InstructionMetadata.empty() &&
  56          "Instructions with metadata have been leaked");
  57 #endif
  58
  59   // Drop references for MDNodes.  Do this before Values get deleted to avoid
  60   // unnecessary RAUW when nodes are still unresolved.
  61   for (auto *I : DistinctMDNodes)
  62     I->dropAllReferences();
  63 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  64   for (auto *I : CLASS##s)                                                     \
  65     I->dropAllReferences();
  66 #include "llvm/IR/Metadata.def"
  67
  68   // Also drop references that come from the Value bridges.
  69   for (auto &Pair : ValuesAsMetadata)
  70     Pair.second->dropUsers();
  71   for (auto &Pair : MetadataAsValues)
  72     Pair.second->dropUse();
  73
  74   // Destroy MDNodes.
  75   for (MDNode *I : DistinctMDNodes)
  76     I->deleteAsSubclass();
  77 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  78   for (CLASS * I : CLASS##s)                                                   \
  79     delete I;
  80 #include "llvm/IR/Metadata.def"
  81
  82   // Free the constants.
  83   for (auto *I : ExprConstants)
  84     I->dropAllReferences();
  85   for (auto *I : ArrayConstants)
  86     I->dropAllReferences();
  87   for (auto *I : StructConstants)
  88     I->dropAllReferences();
  89   for (auto *I : VectorConstants)
  90     I->dropAllReferences();
  91   ExprConstants.freeConstants();
  92   ArrayConstants.freeConstants();
  93   StructConstants.freeConstants();
  94   VectorConstants.freeConstants();
  95   InlineAsms.freeConstants();
  96
  97   CAZConstants.clear();
  98   CPNConstants.clear();
  99   UVConstants.clear();
 100   IntConstants.clear();
 101   FPConstants.clear();
 102
 103   for (auto &CDSConstant : CDSConstants)
 104     delete CDSConstant.second;
 105   CDSConstants.clear();
 106
 107   // Destroy attributes.
 108   for (FoldingSetIterator<AttributeImpl> I = AttrsSet.begin(),
 109          E = AttrsSet.end(); I != E; ) {
 110     FoldingSetIterator<AttributeImpl> Elem = I++;
 111     delete &*Elem;
 112   }
 113
 114   // Destroy attribute lists.
 115   for (FoldingSetIterator<AttributeListImpl> I = AttrsLists.begin(),
 116                                              E = AttrsLists.end();
 117        I != E;) {
 118     FoldingSetIterator<AttributeListImpl> Elem = I++;
 119     delete &*Elem;
 120   }
 121
 122   // Destroy attribute node lists.
 123   for (FoldingSetIterator<AttributeSetNode> I = AttrsSetNodes.begin(),
 124          E = AttrsSetNodes.end(); I != E; ) {
 125     FoldingSetIterator<AttributeSetNode> Elem = I++;
 126     delete &*Elem;
 127   }
 128
 129   // Destroy MetadataAsValues.
 130   {
 131     SmallVector<MetadataAsValue *, 8> MDVs;
 132     MDVs.reserve(MetadataAsValues.size());
 133     for (auto &Pair : MetadataAsValues)
 134       MDVs.push_back(Pair.second);
 135     MetadataAsValues.clear();
 136     for (auto *V : MDVs)
 137       delete V;
 138   }
 139
 140   // Destroy ValuesAsMetadata.
 141   for (auto &Pair : ValuesAsMetadata)
 142     delete Pair.second;
 143 }
 144
 145 void LLVMContextImpl::dropTriviallyDeadConstantArrays() {
 146   bool Changed;
 147   do {
 148     Changed = false;
 149
 150     for (auto I = ArrayConstants.begin(), E = ArrayConstants.end(); I != E;) {
 151       auto *C = *I++;
 152       if (C->use_empty()) {
 153         Changed = true;
 154         C->destroyConstant();
 155       }
 156     }
 157   } while (Changed);
 158 }
 159
 160 void Module::dropTriviallyDeadConstantArrays() {
 161   Context.pImpl->dropTriviallyDeadConstantArrays();
 162 }
 163
 164 namespace llvm {
 165
 166 /// Make MDOperand transparent for hashing.
 167 ///
 168 /// This overload of an implementation detail of the hashing library makes
 169 /// MDOperand hash to the same value as a \a Metadata pointer.
 170 ///
 171 /// Note that overloading \a hash_value() as follows:
 172 ///
 173 /// \code
 174 ///     size_t hash_value(const MDOperand &X) { return hash_value(X.get()); }
 175 /// \endcode
 176 ///
 177 /// does not cause MDOperand to be transparent.  In particular, a bare pointer
 178 /// doesn't get hashed before it's combined, whereas \a MDOperand would.
 179 static const Metadata *get_hashable_data(const MDOperand &X) { return X.get(); }
 180
 181 } // end namespace llvm
 182
 183 unsigned MDNodeOpsKey::calculateHash(MDNode *N, unsigned Offset) {
 184   unsigned Hash = hash_combine_range(N->op_begin() + Offset, N->op_end());
 185 #ifndef NDEBUG
 186   {
 187     SmallVector<Metadata *, 8> MDs(N->op_begin() + Offset, N->op_end());
 188     unsigned RawHash = calculateHash(MDs);
 189     assert(Hash == RawHash &&
 190            "Expected hash of MDOperand to equal hash of Metadata*");
 191   }
 192 #endif
 193   return Hash;
 194 }
 195
 196 unsigned MDNodeOpsKey::calculateHash(ArrayRef<Metadata *> Ops) {
 197   return hash_combine_range(Ops.begin(), Ops.end());
 198 }
 199
 200 StringMapEntry<uint32_t> *LLVMContextImpl::getOrInsertBundleTag(StringRef Tag) {
 201   uint32_t NewIdx = BundleTagCache.size();
 202   return &*(BundleTagCache.insert(std::make_pair(Tag, NewIdx)).first);
 203 }
 204
 205 void LLVMContextImpl::getOperandBundleTags(SmallVectorImpl<StringRef> &Tags) const {
 206   Tags.resize(BundleTagCache.size());
 207   for (const auto &T : BundleTagCache)
 208     Tags[T.second] = T.first();
 209 }
 210
 211 uint32_t LLVMContextImpl::getOperandBundleTagID(StringRef Tag) const {
 212   auto I = BundleTagCache.find(Tag);
 213   assert(I != BundleTagCache.end() && "Unknown tag!");
 214   return I->second;
 215 }
 216
 217 SyncScope::ID LLVMContextImpl::getOrInsertSyncScopeID(StringRef SSN) {
 218   auto NewSSID = SSC.size();
 219   assert(NewSSID < std::numeric_limits<SyncScope::ID>::max() &&
 220          "Hit the maximum number of synchronization scopes allowed!");
 221   return SSC.insert(std::make_pair(SSN, SyncScope::ID(NewSSID))).first->second;
 222 }
 223
 224 void LLVMContextImpl::getSyncScopeNames(
 225     SmallVectorImpl<StringRef> &SSNs) const {
 226   SSNs.resize(SSC.size());
 227   for (const auto &SSE : SSC)
 228     SSNs[SSE.second] = SSE.first();
 229 }
 230
 231 /// Singleton instance of the OptBisect class.
 232 ///
 233 /// This singleton is accessed via the LLVMContext::getOptPassGate() function.
 234 /// It provides a mechanism to disable passes and individual optimizations at
 235 /// compile time based on a command line option (-opt-bisect-limit) in order to
 236 /// perform a bisecting search for optimization-related problems.
 237 ///
 238 /// Even if multiple LLVMContext objects are created, they will all return the
 239 /// same instance of OptBisect in order to provide a single bisect count.  Any
 240 /// code that uses the OptBisect object should be serialized when bisection is
 241 /// enabled in order to enable a consistent bisect count.
 242 static ManagedStatic<OptBisect> OptBisector;
 243
 244 OptPassGate &LLVMContextImpl::getOptPassGate() const {
 245   if (!OPG)
 246     OPG = &(*OptBisector);
 247   return *OPG;
 248 }
 249
 250 void LLVMContextImpl::setOptPassGate(OptPassGate& OPG) {
 251   this->OPG = &OPG;
 252 }