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/IR/DiagnosticHandler.h"
  19 #include "llvm/IR/LLVMRemarkStreamer.h"
  20 #include "llvm/IR/Module.h"
  21 #include "llvm/IR/OptBisect.h"
  22 #include "llvm/IR/Type.h"
  23 #include "llvm/IR/Use.h"
  24 #include "llvm/IR/User.h"
  25 #include "llvm/Remarks/RemarkStreamer.h"
  26 #include "llvm/Support/Compiler.h"
  27 #include "llvm/Support/ErrorHandling.h"
  28 #include <cassert>
  29 #include <utility>
  30
  31 using namespace llvm;
  32
  33 LLVMContextImpl::LLVMContextImpl(LLVMContext &C)
  34     : DiagHandler(std::make_unique<DiagnosticHandler>()),
  35       VoidTy(C, Type::VoidTyID), LabelTy(C, Type::LabelTyID),
  36       HalfTy(C, Type::HalfTyID), BFloatTy(C, Type::BFloatTyID),
  37       FloatTy(C, Type::FloatTyID), DoubleTy(C, Type::DoubleTyID),
  38       MetadataTy(C, Type::MetadataTyID), TokenTy(C, Type::TokenTyID),
  39       X86_FP80Ty(C, Type::X86_FP80TyID), FP128Ty(C, Type::FP128TyID),
  40       PPC_FP128Ty(C, Type::PPC_FP128TyID), X86_AMXTy(C, Type::X86_AMXTyID),
  41       Int1Ty(C, 1), Int8Ty(C, 8), Int16Ty(C, 16), Int32Ty(C, 32),
  42       Int64Ty(C, 64), Int128Ty(C, 128) {}
  43
  44 LLVMContextImpl::~LLVMContextImpl() {
  45 #ifndef NDEBUG
  46   // Check that any variable location records that fell off the end of a block
  47   // when it's terminator was removed were eventually replaced. This assertion
  48   // firing indicates that DbgVariableRecords went missing during the lifetime
  49   // of the LLVMContext.
  50   assert(TrailingDbgRecords.empty() && "DbgRecords in blocks not cleaned");
  51 #endif
  52
  53   // NOTE: We need to delete the contents of OwnedModules, but Module's dtor
  54   // will call LLVMContextImpl::removeModule, thus invalidating iterators into
  55   // the container. Avoid iterators during this operation:
  56   while (!OwnedModules.empty())
  57     delete *OwnedModules.begin();
  58
  59 #ifndef NDEBUG
  60   // Check for metadata references from leaked Values.
  61   for (auto &Pair : ValueMetadata)
  62     Pair.first->dump();
  63   assert(ValueMetadata.empty() && "Values with metadata have been leaked");
  64 #endif
  65
  66   // Drop references for MDNodes.  Do this before Values get deleted to avoid
  67   // unnecessary RAUW when nodes are still unresolved.
  68   for (auto *I : DistinctMDNodes)
  69     I->dropAllReferences();
  70 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  71   for (auto *I : CLASS##s)                                                     \
  72     I->dropAllReferences();
  73 #include "llvm/IR/Metadata.def"
  74
  75   // Also drop references that come from the Value bridges.
  76   for (auto &Pair : ValuesAsMetadata)
  77     Pair.second->dropUsers();
  78   for (auto &Pair : MetadataAsValues)
  79     Pair.second->dropUse();
  80   // Do not untrack ValueAsMetadata references for DIArgLists, as they have
  81   // already been more efficiently untracked above.
  82   for (DIArgList *AL : DIArgLists) {
  83     AL->dropAllReferences(/* Untrack */ false);
  84     delete AL;
  85   }
  86   DIArgLists.clear();
  87
  88   // Destroy MDNodes.
  89   for (MDNode *I : DistinctMDNodes)
  90     I->deleteAsSubclass();
  91
  92   for (auto *ConstantRangeListAttribute : ConstantRangeListAttributes)
  93     ConstantRangeListAttribute->~ConstantRangeListAttributeImpl();
  94 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  95   for (CLASS * I : CLASS##s)                                                   \
  96     delete I;
  97 #include "llvm/IR/Metadata.def"
  98
  99   // Free the constants.
 100   for (auto *I : ExprConstants)
 101     I->dropAllReferences();
 102   for (auto *I : ArrayConstants)
 103     I->dropAllReferences();
 104   for (auto *I : StructConstants)
 105     I->dropAllReferences();
 106   for (auto *I : VectorConstants)
 107     I->dropAllReferences();
 108   ExprConstants.freeConstants();
 109   ArrayConstants.freeConstants();
 110   StructConstants.freeConstants();
 111   VectorConstants.freeConstants();
 112   InlineAsms.freeConstants();
 113
 114   CAZConstants.clear();
 115   CPNConstants.clear();
 116   CTNConstants.clear();
 117   UVConstants.clear();
 118   PVConstants.clear();
 119   IntZeroConstants.clear();
 120   IntOneConstants.clear();
 121   IntConstants.clear();
 122   IntSplatConstants.clear();
 123   FPConstants.clear();
 124   FPSplatConstants.clear();
 125   CDSConstants.clear();
 126
 127   // Destroy attribute node lists.
 128   for (FoldingSetIterator<AttributeSetNode> I = AttrsSetNodes.begin(),
 129          E = AttrsSetNodes.end(); I != E; ) {
 130     FoldingSetIterator<AttributeSetNode> Elem = I++;
 131     delete &*Elem;
 132   }
 133
 134   // Destroy MetadataAsValues.
 135   {
 136     SmallVector<MetadataAsValue *, 8> MDVs;
 137     MDVs.reserve(MetadataAsValues.size());
 138     for (auto &Pair : MetadataAsValues)
 139       MDVs.push_back(Pair.second);
 140     MetadataAsValues.clear();
 141     for (auto *V : MDVs)
 142       delete V;
 143   }
 144
 145   // Destroy ValuesAsMetadata.
 146   for (auto &Pair : ValuesAsMetadata)
 147     delete Pair.second;
 148 }
 149
 150 void LLVMContextImpl::dropTriviallyDeadConstantArrays() {
 151   SmallSetVector<ConstantArray *, 4> WorkList;
 152
 153   // When ArrayConstants are of substantial size and only a few in them are
 154   // dead, starting WorkList with all elements of ArrayConstants can be
 155   // wasteful. Instead, starting WorkList with only elements that have empty
 156   // uses.
 157   for (ConstantArray *C : ArrayConstants)
 158     if (C->use_empty())
 159       WorkList.insert(C);
 160
 161   while (!WorkList.empty()) {
 162     ConstantArray *C = WorkList.pop_back_val();
 163     if (C->use_empty()) {
 164       for (const Use &Op : C->operands()) {
 165         if (auto *COp = dyn_cast<ConstantArray>(Op))
 166           WorkList.insert(COp);
 167       }
 168       C->destroyConstant();
 169     }
 170   }
 171 }
 172
 173 void Module::dropTriviallyDeadConstantArrays() {
 174   Context.pImpl->dropTriviallyDeadConstantArrays();
 175 }
 176
 177 namespace llvm {
 178
 179 /// Make MDOperand transparent for hashing.
 180 ///
 181 /// This overload of an implementation detail of the hashing library makes
 182 /// MDOperand hash to the same value as a \a Metadata pointer.
 183 ///
 184 /// Note that overloading \a hash_value() as follows:
 185 ///
 186 /// \code
 187 ///     size_t hash_value(const MDOperand &X) { return hash_value(X.get()); }
 188 /// \endcode
 189 ///
 190 /// does not cause MDOperand to be transparent.  In particular, a bare pointer
 191 /// doesn't get hashed before it's combined, whereas \a MDOperand would.
 192 static const Metadata *get_hashable_data(const MDOperand &X) { return X.get(); }
 193
 194 } // end namespace llvm
 195
 196 unsigned MDNodeOpsKey::calculateHash(MDNode *N, unsigned Offset) {
 197   unsigned Hash = hash_combine_range(N->op_begin() + Offset, N->op_end());
 198 #ifndef NDEBUG
 199   {
 200     SmallVector<Metadata *, 8> MDs(drop_begin(N->operands(), Offset));
 201     unsigned RawHash = calculateHash(MDs);
 202     assert(Hash == RawHash &&
 203            "Expected hash of MDOperand to equal hash of Metadata*");
 204   }
 205 #endif
 206   return Hash;
 207 }
 208
 209 unsigned MDNodeOpsKey::calculateHash(ArrayRef<Metadata *> Ops) {
 210   return hash_combine_range(Ops.begin(), Ops.end());
 211 }
 212
 213 StringMapEntry<uint32_t> *LLVMContextImpl::getOrInsertBundleTag(StringRef Tag) {
 214   uint32_t NewIdx = BundleTagCache.size();
 215   return &*(BundleTagCache.insert(std::make_pair(Tag, NewIdx)).first);
 216 }
 217
 218 void LLVMContextImpl::getOperandBundleTags(SmallVectorImpl<StringRef> &Tags) const {
 219   Tags.resize(BundleTagCache.size());
 220   for (const auto &T : BundleTagCache)
 221     Tags[T.second] = T.first();
 222 }
 223
 224 uint32_t LLVMContextImpl::getOperandBundleTagID(StringRef Tag) const {
 225   auto I = BundleTagCache.find(Tag);
 226   assert(I != BundleTagCache.end() && "Unknown tag!");
 227   return I->second;
 228 }
 229
 230 SyncScope::ID LLVMContextImpl::getOrInsertSyncScopeID(StringRef SSN) {
 231   auto NewSSID = SSC.size();
 232   assert(NewSSID < std::numeric_limits<SyncScope::ID>::max() &&
 233          "Hit the maximum number of synchronization scopes allowed!");
 234   return SSC.insert(std::make_pair(SSN, SyncScope::ID(NewSSID))).first->second;
 235 }
 236
 237 void LLVMContextImpl::getSyncScopeNames(
 238     SmallVectorImpl<StringRef> &SSNs) const {
 239   SSNs.resize(SSC.size());
 240   for (const auto &SSE : SSC)
 241     SSNs[SSE.second] = SSE.first();
 242 }
 243
 244 std::optional<StringRef>
 245 LLVMContextImpl::getSyncScopeName(SyncScope::ID Id) const {
 246   for (const auto &SSE : SSC) {
 247     if (SSE.second != Id)
 248       continue;
 249     return SSE.first();
 250   }
 251   return std::nullopt;
 252 }
 253
 254 /// Gets the OptPassGate for this LLVMContextImpl, which defaults to the
 255 /// singleton OptBisect if not explicitly set.
 256 OptPassGate &LLVMContextImpl::getOptPassGate() const {
 257   if (!OPG)
 258     OPG = &getGlobalPassGate();
 259   return *OPG;
 260 }
 261
 262 void LLVMContextImpl::setOptPassGate(OptPassGate& OPG) {
 263   this->OPG = &OPG;
 264 }