llvm/lib/IR/LLVMContextImpl.cpp

   1 //===- LLVMContextImpl.cpp - Implement LLVMContextImpl --------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 //  This file implements the opaque LLVMContextImpl.
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #include "LLVMContextImpl.h"
  14 #include "AttributeImpl.h"
  15 #include "llvm/ADT/SetVector.h"
  16 #include "llvm/ADT/StringMapEntry.h"
  17 #include "llvm/ADT/iterator.h"
  18 #include "llvm/ADT/iterator_range.h"
  19 #include "llvm/IR/DiagnosticHandler.h"
  20 #include "llvm/IR/LLVMRemarkStreamer.h"
  21 #include "llvm/IR/Module.h"
  22 #include "llvm/IR/OptBisect.h"
  23 #include "llvm/IR/Type.h"
  24 #include "llvm/IR/Use.h"
  25 #include "llvm/IR/User.h"
  26 #include "llvm/Remarks/RemarkStreamer.h"
  27 #include "llvm/Support/CommandLine.h"
  28 #include "llvm/Support/Compiler.h"
  29 #include "llvm/Support/ErrorHandling.h"
  30 #include "llvm/Support/TypeSize.h"
  31 #include <cassert>
  32 #include <utility>
  33
  34 using namespace llvm;
  35
  36 LLVMContextImpl::LLVMContextImpl(LLVMContext &C)
  37     : DiagHandler(std::make_unique<DiagnosticHandler>()),
  38       VoidTy(C, Type::VoidTyID), LabelTy(C, Type::LabelTyID),
  39       HalfTy(C, Type::HalfTyID), BFloatTy(C, Type::BFloatTyID),
  40       FloatTy(C, Type::FloatTyID), DoubleTy(C, Type::DoubleTyID),
  41       MetadataTy(C, Type::MetadataTyID), TokenTy(C, Type::TokenTyID),
  42       X86_FP80Ty(C, Type::X86_FP80TyID), FP128Ty(C, Type::FP128TyID),
  43       PPC_FP128Ty(C, Type::PPC_FP128TyID), X86_MMXTy(C, Type::X86_MMXTyID),
  44       X86_AMXTy(C, Type::X86_AMXTyID), Int1Ty(C, 1), Int8Ty(C, 8),
  45       Int16Ty(C, 16), Int32Ty(C, 32), Int64Ty(C, 64), Int128Ty(C, 128) {}
  46
  47 LLVMContextImpl::~LLVMContextImpl() {
  48   // NOTE: We need to delete the contents of OwnedModules, but Module's dtor
  49   // will call LLVMContextImpl::removeModule, thus invalidating iterators into
  50   // the container. Avoid iterators during this operation:
  51   while (!OwnedModules.empty())
  52     delete *OwnedModules.begin();
  53
  54 #ifndef NDEBUG
  55   // Check for metadata references from leaked Values.
  56   for (auto &Pair : ValueMetadata)
  57     Pair.first->dump();
  58   assert(ValueMetadata.empty() && "Values with metadata have been leaked");
  59 #endif
  60
  61   // Drop references for MDNodes.  Do this before Values get deleted to avoid
  62   // unnecessary RAUW when nodes are still unresolved.
  63   for (auto *I : DistinctMDNodes) {
  64     // We may have DIArgList that were uniqued, and as it has a custom
  65     // implementation of dropAllReferences, it needs to be explicitly invoked.
  66     if (auto *AL = dyn_cast<DIArgList>(I)) {
  67       AL->dropAllReferences();
  68       continue;
  69     }
  70     I->dropAllReferences();
  71   }
  72 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  73   for (auto *I : CLASS##s)                                                     \
  74     I->dropAllReferences();
  75 #include "llvm/IR/Metadata.def"
  76
  77   // Also drop references that come from the Value bridges.
  78   for (auto &Pair : ValuesAsMetadata)
  79     Pair.second->dropUsers();
  80   for (auto &Pair : MetadataAsValues)
  81     Pair.second->dropUse();
  82
  83   // Destroy MDNodes.
  84   for (MDNode *I : DistinctMDNodes)
  85     I->deleteAsSubclass();
  86 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  87   for (CLASS * I : CLASS##s)                                                   \
  88     delete I;
  89 #include "llvm/IR/Metadata.def"
  90
  91   // Free the constants.
  92   for (auto *I : ExprConstants)
  93     I->dropAllReferences();
  94   for (auto *I : ArrayConstants)
  95     I->dropAllReferences();
  96   for (auto *I : StructConstants)
  97     I->dropAllReferences();
  98   for (auto *I : VectorConstants)
  99     I->dropAllReferences();
 100   ExprConstants.freeConstants();
 101   ArrayConstants.freeConstants();
 102   StructConstants.freeConstants();
 103   VectorConstants.freeConstants();
 104   InlineAsms.freeConstants();
 105
 106   CAZConstants.clear();
 107   CPNConstants.clear();
 108   CTNConstants.clear();
 109   UVConstants.clear();
 110   PVConstants.clear();
 111   IntZeroConstants.clear();
 112   IntOneConstants.clear();
 113   IntConstants.clear();
 114   FPConstants.clear();
 115   CDSConstants.clear();
 116
 117   // Destroy attribute node lists.
 118   for (FoldingSetIterator<AttributeSetNode> I = AttrsSetNodes.begin(),
 119          E = AttrsSetNodes.end(); I != E; ) {
 120     FoldingSetIterator<AttributeSetNode> Elem = I++;
 121     delete &*Elem;
 122   }
 123
 124   // Destroy MetadataAsValues.
 125   {
 126     SmallVector<MetadataAsValue *, 8> MDVs;
 127     MDVs.reserve(MetadataAsValues.size());
 128     for (auto &Pair : MetadataAsValues)
 129       MDVs.push_back(Pair.second);
 130     MetadataAsValues.clear();
 131     for (auto *V : MDVs)
 132       delete V;
 133   }
 134
 135   // Destroy ValuesAsMetadata.
 136   for (auto &Pair : ValuesAsMetadata)
 137     delete Pair.second;
 138 }
 139
 140 void LLVMContextImpl::dropTriviallyDeadConstantArrays() {
 141   SmallSetVector<ConstantArray *, 4> WorkList;
 142
 143   // When ArrayConstants are of substantial size and only a few in them are
 144   // dead, starting WorkList with all elements of ArrayConstants can be
 145   // wasteful. Instead, starting WorkList with only elements that have empty
 146   // uses.
 147   for (ConstantArray *C : ArrayConstants)
 148     if (C->use_empty())
 149       WorkList.insert(C);
 150
 151   while (!WorkList.empty()) {
 152     ConstantArray *C = WorkList.pop_back_val();
 153     if (C->use_empty()) {
 154       for (const Use &Op : C->operands()) {
 155         if (auto *COp = dyn_cast<ConstantArray>(Op))
 156           WorkList.insert(COp);
 157       }
 158       C->destroyConstant();
 159     }
 160   }
 161 }
 162
 163 void Module::dropTriviallyDeadConstantArrays() {
 164   Context.pImpl->dropTriviallyDeadConstantArrays();
 165 }
 166
 167 namespace llvm {
 168
 169 /// Make MDOperand transparent for hashing.
 170 ///
 171 /// This overload of an implementation detail of the hashing library makes
 172 /// MDOperand hash to the same value as a \a Metadata pointer.
 173 ///
 174 /// Note that overloading \a hash_value() as follows:
 175 ///
 176 /// \code
 177 ///     size_t hash_value(const MDOperand &X) { return hash_value(X.get()); }
 178 /// \endcode
 179 ///
 180 /// does not cause MDOperand to be transparent.  In particular, a bare pointer
 181 /// doesn't get hashed before it's combined, whereas \a MDOperand would.
 182 static const Metadata *get_hashable_data(const MDOperand &X) { return X.get(); }
 183
 184 } // end namespace llvm
 185
 186 unsigned MDNodeOpsKey::calculateHash(MDNode *N, unsigned Offset) {
 187   unsigned Hash = hash_combine_range(N->op_begin() + Offset, N->op_end());
 188 #ifndef NDEBUG
 189   {
 190     SmallVector<Metadata *, 8> MDs(drop_begin(N->operands(), Offset));
 191     unsigned RawHash = calculateHash(MDs);
 192     assert(Hash == RawHash &&
 193            "Expected hash of MDOperand to equal hash of Metadata*");
 194   }
 195 #endif
 196   return Hash;
 197 }
 198
 199 unsigned MDNodeOpsKey::calculateHash(ArrayRef<Metadata *> Ops) {
 200   return hash_combine_range(Ops.begin(), Ops.end());
 201 }
 202
 203 StringMapEntry<uint32_t> *LLVMContextImpl::getOrInsertBundleTag(StringRef Tag) {
 204   uint32_t NewIdx = BundleTagCache.size();
 205   return &*(BundleTagCache.insert(std::make_pair(Tag, NewIdx)).first);
 206 }
 207
 208 void LLVMContextImpl::getOperandBundleTags(SmallVectorImpl<StringRef> &Tags) const {
 209   Tags.resize(BundleTagCache.size());
 210   for (const auto &T : BundleTagCache)
 211     Tags[T.second] = T.first();
 212 }
 213
 214 uint32_t LLVMContextImpl::getOperandBundleTagID(StringRef Tag) const {
 215   auto I = BundleTagCache.find(Tag);
 216   assert(I != BundleTagCache.end() && "Unknown tag!");
 217   return I->second;
 218 }
 219
 220 SyncScope::ID LLVMContextImpl::getOrInsertSyncScopeID(StringRef SSN) {
 221   auto NewSSID = SSC.size();
 222   assert(NewSSID < std::numeric_limits<SyncScope::ID>::max() &&
 223          "Hit the maximum number of synchronization scopes allowed!");
 224   return SSC.insert(std::make_pair(SSN, SyncScope::ID(NewSSID))).first->second;
 225 }
 226
 227 void LLVMContextImpl::getSyncScopeNames(
 228     SmallVectorImpl<StringRef> &SSNs) const {
 229   SSNs.resize(SSC.size());
 230   for (const auto &SSE : SSC)
 231     SSNs[SSE.second] = SSE.first();
 232 }
 233
 234 /// Gets the OptPassGate for this LLVMContextImpl, which defaults to the
 235 /// singleton OptBisect if not explicitly set.
 236 OptPassGate &LLVMContextImpl::getOptPassGate() const {
 237   if (!OPG)
 238     OPG = &getGlobalPassGate();
 239   return *OPG;
 240 }
 241
 242 void LLVMContextImpl::setOptPassGate(OptPassGate& OPG) {
 243   this->OPG = &OPG;
 244 }