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 #ifndef NDEBUG
  49   // Check that any variable location records that fell off the end of a block
  50   // when it's terminator was removed were eventually replaced. This assertion
  51   // firing indicates that DPValues went missing during the lifetime of the
  52   // LLVMContext.
  53   assert(TrailingDPValues.empty() && "DPValue records in blocks not cleaned");
  54 #endif
  55
  56   // NOTE: We need to delete the contents of OwnedModules, but Module's dtor
  57   // will call LLVMContextImpl::removeModule, thus invalidating iterators into
  58   // the container. Avoid iterators during this operation:
  59   while (!OwnedModules.empty())
  60     delete *OwnedModules.begin();
  61
  62 #ifndef NDEBUG
  63   // Check for metadata references from leaked Values.
  64   for (auto &Pair : ValueMetadata)
  65     Pair.first->dump();
  66   assert(ValueMetadata.empty() && "Values with metadata have been leaked");
  67 #endif
  68
  69   // Drop references for MDNodes.  Do this before Values get deleted to avoid
  70   // unnecessary RAUW when nodes are still unresolved.
  71   for (auto *I : DistinctMDNodes)
  72     I->dropAllReferences();
  73 #define HANDLE_MDNODE_LEAF_UNIQUABLE(CLASS)                                    \
  74   for (auto *I : CLASS##s)                                                     \
  75     I->dropAllReferences();
  76 #include "llvm/IR/Metadata.def"
  77
  78   // Also drop references that come from the Value bridges.
  79   for (auto &Pair : ValuesAsMetadata)
  80     Pair.second->dropUsers();
  81   for (auto &Pair : MetadataAsValues)
  82     Pair.second->dropUse();
  83   // Do not untrack ValueAsMetadata references for DIArgLists, as they have
  84   // already been more efficiently untracked above.
  85   for (DIArgList *AL : DIArgLists) {
  86     AL->dropAllReferences(/* Untrack */ false);
  87     delete AL;
  88   }
  89   DIArgLists.clear();
  90
  91   // Destroy MDNodes.
  92   for (MDNode *I : DistinctMDNodes)
  93     I->deleteAsSubclass();
  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   FPConstants.clear();
 123   CDSConstants.clear();
 124
 125   // Destroy attribute node lists.
 126   for (FoldingSetIterator<AttributeSetNode> I = AttrsSetNodes.begin(),
 127          E = AttrsSetNodes.end(); I != E; ) {
 128     FoldingSetIterator<AttributeSetNode> Elem = I++;
 129     delete &*Elem;
 130   }
 131
 132   // Destroy MetadataAsValues.
 133   {
 134     SmallVector<MetadataAsValue *, 8> MDVs;
 135     MDVs.reserve(MetadataAsValues.size());
 136     for (auto &Pair : MetadataAsValues)
 137       MDVs.push_back(Pair.second);
 138     MetadataAsValues.clear();
 139     for (auto *V : MDVs)
 140       delete V;
 141   }
 142
 143   // Destroy ValuesAsMetadata.
 144   for (auto &Pair : ValuesAsMetadata)
 145     delete Pair.second;
 146 }
 147
 148 void LLVMContextImpl::dropTriviallyDeadConstantArrays() {
 149   SmallSetVector<ConstantArray *, 4> WorkList;
 150
 151   // When ArrayConstants are of substantial size and only a few in them are
 152   // dead, starting WorkList with all elements of ArrayConstants can be
 153   // wasteful. Instead, starting WorkList with only elements that have empty
 154   // uses.
 155   for (ConstantArray *C : ArrayConstants)
 156     if (C->use_empty())
 157       WorkList.insert(C);
 158
 159   while (!WorkList.empty()) {
 160     ConstantArray *C = WorkList.pop_back_val();
 161     if (C->use_empty()) {
 162       for (const Use &Op : C->operands()) {
 163         if (auto *COp = dyn_cast<ConstantArray>(Op))
 164           WorkList.insert(COp);
 165       }
 166       C->destroyConstant();
 167     }
 168   }
 169 }
 170
 171 void Module::dropTriviallyDeadConstantArrays() {
 172   Context.pImpl->dropTriviallyDeadConstantArrays();
 173 }
 174
 175 namespace llvm {
 176
 177 /// Make MDOperand transparent for hashing.
 178 ///
 179 /// This overload of an implementation detail of the hashing library makes
 180 /// MDOperand hash to the same value as a \a Metadata pointer.
 181 ///
 182 /// Note that overloading \a hash_value() as follows:
 183 ///
 184 /// \code
 185 ///     size_t hash_value(const MDOperand &X) { return hash_value(X.get()); }
 186 /// \endcode
 187 ///
 188 /// does not cause MDOperand to be transparent.  In particular, a bare pointer
 189 /// doesn't get hashed before it's combined, whereas \a MDOperand would.
 190 static const Metadata *get_hashable_data(const MDOperand &X) { return X.get(); }
 191
 192 } // end namespace llvm
 193
 194 unsigned MDNodeOpsKey::calculateHash(MDNode *N, unsigned Offset) {
 195   unsigned Hash = hash_combine_range(N->op_begin() + Offset, N->op_end());
 196 #ifndef NDEBUG
 197   {
 198     SmallVector<Metadata *, 8> MDs(drop_begin(N->operands(), Offset));
 199     unsigned RawHash = calculateHash(MDs);
 200     assert(Hash == RawHash &&
 201            "Expected hash of MDOperand to equal hash of Metadata*");
 202   }
 203 #endif
 204   return Hash;
 205 }
 206
 207 unsigned MDNodeOpsKey::calculateHash(ArrayRef<Metadata *> Ops) {
 208   return hash_combine_range(Ops.begin(), Ops.end());
 209 }
 210
 211 StringMapEntry<uint32_t> *LLVMContextImpl::getOrInsertBundleTag(StringRef Tag) {
 212   uint32_t NewIdx = BundleTagCache.size();
 213   return &*(BundleTagCache.insert(std::make_pair(Tag, NewIdx)).first);
 214 }
 215
 216 void LLVMContextImpl::getOperandBundleTags(SmallVectorImpl<StringRef> &Tags) const {
 217   Tags.resize(BundleTagCache.size());
 218   for (const auto &T : BundleTagCache)
 219     Tags[T.second] = T.first();
 220 }
 221
 222 uint32_t LLVMContextImpl::getOperandBundleTagID(StringRef Tag) const {
 223   auto I = BundleTagCache.find(Tag);
 224   assert(I != BundleTagCache.end() && "Unknown tag!");
 225   return I->second;
 226 }
 227
 228 SyncScope::ID LLVMContextImpl::getOrInsertSyncScopeID(StringRef SSN) {
 229   auto NewSSID = SSC.size();
 230   assert(NewSSID < std::numeric_limits<SyncScope::ID>::max() &&
 231          "Hit the maximum number of synchronization scopes allowed!");
 232   return SSC.insert(std::make_pair(SSN, SyncScope::ID(NewSSID))).first->second;
 233 }
 234
 235 void LLVMContextImpl::getSyncScopeNames(
 236     SmallVectorImpl<StringRef> &SSNs) const {
 237   SSNs.resize(SSC.size());
 238   for (const auto &SSE : SSC)
 239     SSNs[SSE.second] = SSE.first();
 240 }
 241
 242 /// Gets the OptPassGate for this LLVMContextImpl, which defaults to the
 243 /// singleton OptBisect if not explicitly set.
 244 OptPassGate &LLVMContextImpl::getOptPassGate() const {
 245   if (!OPG)
 246     OPG = &getGlobalPassGate();
 247   return *OPG;
 248 }
 249
 250 void LLVMContextImpl::setOptPassGate(OptPassGate& OPG) {
 251   this->OPG = &OPG;
 252 }