lib/VMCore/ValueSymbolTable.cpp

   1 //===-- ValueSymbolTable.cpp - Implement the ValueSymbolTable class -------===//
   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 ValueSymbolTable class for the VMCore library.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #define DEBUG_TYPE "valuesymtab"
  15 #include "llvm/GlobalValue.h"
  16 #include "llvm/Type.h"
  17 #include "llvm/ValueSymbolTable.h"
  18 #include "llvm/ADT/SmallString.h"
  19 #include "llvm/Support/Debug.h"
  20 using namespace llvm;
  21
  22 // Class destructor
  23 ValueSymbolTable::~ValueSymbolTable() {
  24 #ifndef NDEBUG   // Only do this in -g mode...
  25   for (iterator VI = vmap.begin(), VE = vmap.end(); VI != VE; ++VI)
  26     cerr << "Value still in symbol table! Type = '"
  27          << VI->getValue()->getType()->getDescription() << "' Name = '"
  28          << VI->getKeyData() << "'\n";
  29   assert(vmap.empty() && "Values remain in symbol table!");
  30 #endif
  31 }
  32
  33 // lookup a value - Returns null on failure...
  34 //
  35 Value *ValueSymbolTable::lookup(const std::string &Name) const {
  36   const_iterator VI = vmap.find(Name.data(), Name.data() + Name.size());
  37   if (VI != vmap.end())                   // We found the symbol
  38     return VI->getValue();
  39   return 0;
  40 }
  41
  42 Value *ValueSymbolTable::lookup(const char *NameBegin,
  43                                 const char *NameEnd) const {
  44   const_iterator VI = vmap.find(NameBegin, NameEnd);
  45   if (VI != vmap.end())                   // We found the symbol
  46     return VI->getValue();
  47   return 0;
  48 }
  49
  50 // Insert a value into the symbol table with the specified name...
  51 //
  52 void ValueSymbolTable::reinsertValue(Value* V) {
  53   assert(V->hasName() && "Can't insert nameless Value into symbol table");
  54
  55   // Try inserting the name, assuming it won't conflict.
  56   if (vmap.insert(V->Name)) {
  57     //DOUT << " Inserted value: " << V->Name << ": " << *V << "\n";
  58     return;
  59   }
  60
  61   // Otherwise, there is a naming conflict.  Rename this value.
  62   SmallString<128> UniqueName(V->getNameStart(), V->getNameEnd());
  63
  64   // The name is too already used, just free it so we can allocate a new name.
  65   V->Name->Destroy();
  66
  67   unsigned BaseSize = UniqueName.size();
  68   while (1) {
  69     // Trim any suffix off.
  70     UniqueName.resize(BaseSize);
  71     UniqueName.append_uint_32(++LastUnique);
  72     // Try insert the vmap entry with this suffix.
  73     ValueName &NewName =
  74       vmap.GetOrCreateValue(UniqueName.data(),
  75                             UniqueName.data() + UniqueName.size());
  76     if (NewName.getValue() == 0) {
  77       // Newly inserted name.  Success!
  78       NewName.setValue(V);
  79       V->Name = &NewName;
  80       //DEBUG(DOUT << " Inserted value: " << UniqueName << ": " << *V << "\n");
  81       return;
  82     }
  83   }
  84 }
  85
  86 void ValueSymbolTable::removeValueName(ValueName *V) {
  87   //DEBUG(DOUT << " Removing Value: " << V->getKeyData() << "\n");
  88   // Remove the value from the symbol table.
  89   vmap.remove(V);
  90 }
  91
  92 /// createValueName - This method attempts to create a value name and insert
  93 /// it into the symbol table with the specified name.  If it conflicts, it
  94 /// auto-renames the name and returns that instead.
  95 ValueName *ValueSymbolTable::createValueName(const char *NameStart,
  96                                              unsigned NameLen, Value *V) {
  97   // In the common case, the name is not already in the symbol table.
  98   ValueName &Entry = vmap.GetOrCreateValue(NameStart, NameStart+NameLen);
  99   if (Entry.getValue() == 0) {
 100     Entry.setValue(V);
 101     //DEBUG(DOUT << " Inserted value: " << Entry.getKeyData() << ": "
 102     //           << *V << "\n");
 103     return &Entry;
 104   }
 105
 106   // Otherwise, there is a naming conflict.  Rename this value.
 107   SmallString<128> UniqueName(NameStart, NameStart+NameLen);
 108
 109   while (1) {
 110     // Trim any suffix off.
 111     UniqueName.resize(NameLen);
 112     UniqueName.append_uint_32(++LastUnique);
 113
 114     // Try insert the vmap entry with this suffix.
 115     ValueName &NewName =
 116       vmap.GetOrCreateValue(UniqueName.data(),
 117                             UniqueName.data() + UniqueName.size());
 118     if (NewName.getValue() == 0) {
 119       // Newly inserted name.  Success!
 120       NewName.setValue(V);
 121       //DEBUG(DOUT << " Inserted value: " << UniqueName << ": " << *V << "\n");
 122       return &NewName;
 123     }
 124   }
 125 }
 126
 127
 128 // dump - print out the symbol table
 129 //
 130 void ValueSymbolTable::dump() const {
 131   //DOUT << "ValueSymbolTable:\n";
 132   for (const_iterator I = begin(), E = end(); I != E; ++I) {
 133     //DOUT << "  '" << I->getKeyData() << "' = ";
 134     I->getValue()->dump();
 135     //DOUT << "\n";
 136   }
 137 }