1 //===- ValueSymbolTable.cpp - Implement the ValueSymbolTable class --------===// 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 ValueSymbolTable class for the IR library. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "llvm/IR/ValueSymbolTable.h" 14 #include "llvm/ADT/SmallString.h" 15 #include "llvm/Config/llvm-config.h" 16 #include "llvm/IR/GlobalValue.h" 17 #include "llvm/IR/Module.h" 18 #include "llvm/IR/Type.h" 19 #include "llvm/IR/Value.h" 20 #include "llvm/Support/Casting.h" 21 #include "llvm/Support/Compiler.h" 22 #include "llvm/Support/Debug.h" 23 #include "llvm/Support/raw_ostream.h" 24 #include "llvm/TargetParser/Triple.h" 25 #include <cassert> 26 #include <utility> 27 28 using namespace llvm; 29 30 #define DEBUG_TYPE "valuesymtab" 31 32 // Class destructor 33 ValueSymbolTable::~ValueSymbolTable() { 34 #ifndef NDEBUG // Only do this in -g mode... 35 for (const auto &VI : vmap) 36 dbgs() << "Value still in symbol table! Type = '" 37 << *VI.getValue()->getType() << "' Name = '" << VI.getKeyData() 38 << "'\n"; 39 assert(vmap.empty() && "Values remain in symbol table!"); 40 #endif 41 } 42 43 ValueName *ValueSymbolTable::makeUniqueName(Value *V, 44 SmallString<256> &UniqueName) { 45 unsigned BaseSize = UniqueName.size(); 46 while (true) { 47 // Trim any suffix off and append the next number. 48 UniqueName.resize(BaseSize); 49 raw_svector_ostream S(UniqueName); 50 if (auto *GV = dyn_cast<GlobalValue>(V)) { 51 // A dot is appended to mark it as clone during ABI demangling so that 52 // for example "_Z1fv" and "_Z1fv.1" both demangle to "f()", the second 53 // one being a clone. 54 // On NVPTX we cannot use a dot because PTX only allows [A-Za-z0-9_$] for 55 // identifiers. This breaks ABI demangling but at least ptxas accepts and 56 // compiles the program. 57 const Module *M = GV->getParent(); 58 if (!(M && Triple(M->getTargetTriple()).isNVPTX())) 59 S << "."; 60 } 61 S << ++LastUnique; 62 63 // Try insert the vmap entry with this suffix. 64 auto IterBool = vmap.insert(std::make_pair(UniqueName.str(), V)); 65 if (IterBool.second) 66 return &*IterBool.first; 67 } 68 } 69 70 // Insert a value into the symbol table with the specified name... 71 // 72 void ValueSymbolTable::reinsertValue(Value *V) { 73 assert(V->hasName() && "Can't insert nameless Value into symbol table"); 74 75 // Try inserting the name, assuming it won't conflict. 76 if (vmap.insert(V->getValueName())) { 77 // LLVM_DEBUG(dbgs() << " Inserted value: " << V->getValueName() << ": " << 78 // *V << "\n"); 79 return; 80 } 81 82 // Otherwise, there is a naming conflict. Rename this value. 83 SmallString<256> UniqueName(V->getName().begin(), V->getName().end()); 84 85 // The name is too already used, just free it so we can allocate a new name. 86 MallocAllocator Allocator; 87 V->getValueName()->Destroy(Allocator); 88 89 ValueName *VN = makeUniqueName(V, UniqueName); 90 V->setValueName(VN); 91 } 92 93 void ValueSymbolTable::removeValueName(ValueName *V) { 94 // LLVM_DEBUG(dbgs() << " Removing Value: " << V->getKeyData() << "\n"); 95 // Remove the value from the symbol table. 96 vmap.remove(V); 97 } 98 99 /// createValueName - This method attempts to create a value name and insert 100 /// it into the symbol table with the specified name. If it conflicts, it 101 /// auto-renames the name and returns that instead. 102 ValueName *ValueSymbolTable::createValueName(StringRef Name, Value *V) { 103 if (MaxNameSize > -1 && Name.size() > (unsigned)MaxNameSize) 104 Name = Name.substr(0, std::max(1u, (unsigned)MaxNameSize)); 105 106 // In the common case, the name is not already in the symbol table. 107 auto IterBool = vmap.insert(std::make_pair(Name, V)); 108 if (IterBool.second) { 109 // LLVM_DEBUG(dbgs() << " Inserted value: " << Entry.getKeyData() << ": " 110 // << *V << "\n"); 111 return &*IterBool.first; 112 } 113 114 // Otherwise, there is a naming conflict. Rename this value. 115 SmallString<256> UniqueName(Name.begin(), Name.end()); 116 return makeUniqueName(V, UniqueName); 117 } 118 119 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 120 // dump - print out the symbol table 121 // 122 LLVM_DUMP_METHOD void ValueSymbolTable::dump() const { 123 // dbgs() << "ValueSymbolTable:\n"; 124 for (const auto &I : *this) { 125 // dbgs() << " '" << I->getKeyData() << "' = "; 126 I.getValue()->dump(); 127 // dbgs() << "\n"; 128 } 129 } 130 #endif 131