src/base/loader/symtab.hh

   1 /*
   2  * Copyright (c) 2002-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  */
  28
  29 #ifndef __SYMTAB_HH__
  30 #define __SYMTAB_HH__
  31
  32 #include <functional>
  33 #include <iosfwd>
  34 #include <map>
  35 #include <memory>
  36 #include <string>
  37 #include <vector>
  38
  39 #include "base/trace.hh"
  40 #include "base/types.hh"
  41 #include "sim/serialize.hh"
  42
  43 namespace Loader
  44 {
  45
  46 struct Symbol
  47 {
  48     enum class Binding {
  49         Global,
  50         Local,
  51         Weak
  52     };
  53
  54     Binding binding;
  55     std::string name;
  56     Addr address;
  57 };
  58
  59 class SymbolTable
  60 {
  61   public:
  62     typedef std::shared_ptr<SymbolTable> SymbolTablePtr;
  63
  64   private:
  65     typedef std::vector<Symbol> SymbolVector;
  66     // Map addresses to an index into the symbol vector.
  67     typedef std::multimap<Addr, int> AddrMap;
  68     // Map a symbol name to an index into the symbol vector.
  69     typedef std::map<std::string, int> NameMap;
  70
  71     SymbolVector symbols;
  72     AddrMap addrMap;
  73     NameMap nameMap;
  74
  75     bool
  76     upperBound(Addr addr, AddrMap::const_iterator &iter) const
  77     {
  78         // find first key *larger* than desired address
  79         iter = addrMap.upper_bound(addr);
  80
  81         // if very first key is larger, we're out of luck
  82         if (iter == addrMap.begin())
  83             return false;
  84
  85         return true;
  86     }
  87
  88     typedef std::function<void(SymbolTable &symtab,
  89                                const Symbol &symbol)> SymTabOp;
  90     SymbolTablePtr
  91     operate(SymTabOp op) const
  92     {
  93         SymbolTablePtr symtab(new SymbolTable);
  94         for (const auto &symbol: symbols)
  95             op(*symtab, symbol);
  96         return symtab;
  97     }
  98
  99     typedef std::function<bool(const Symbol &symbol)> SymTabFilter;
 100     SymbolTablePtr
 101     filter(SymTabFilter filter) const
 102     {
 103         SymTabOp apply_filter =
 104             [filter](SymbolTable &symtab, const Symbol &symbol) {
 105             if (filter(symbol)) {
 106                 symtab.insert(symbol);
 107             }
 108         };
 109         return operate(apply_filter);
 110     }
 111
 112     SymbolTablePtr
 113     filterByBinding(Symbol::Binding binding) const
 114     {
 115         auto filt = [binding](const Symbol &symbol) {
 116             return symbol.binding == binding;
 117         };
 118         return filter(filt);
 119     }
 120
 121   public:
 122     typedef SymbolVector::iterator iterator;
 123     typedef SymbolVector::const_iterator const_iterator;
 124
 125     const_iterator begin() const { return symbols.begin(); }
 126     const_iterator end() const { return symbols.end(); }
 127
 128     void clear();
 129     // Insert either a single symbol or the contents of an entire symbol table
 130     // into this one.
 131     bool insert(const Symbol &symbol);
 132     bool insert(const SymbolTable &other);
 133     bool load(const std::string &file);
 134     bool empty() const { return symbols.empty(); }
 135
 136     SymbolTablePtr
 137     offset(Addr by) const
 138     {
 139         SymTabOp op = [by](SymbolTable &symtab, const Symbol &symbol) {
 140             Symbol sym = symbol;
 141             sym.address += by;
 142             symtab.insert(sym);
 143         };
 144         return operate(op);
 145     }
 146
 147     SymbolTablePtr
 148     mask(Addr m) const
 149     {
 150         SymTabOp op = [m](SymbolTable &symtab, const Symbol &symbol) {
 151             Symbol sym = symbol;
 152             sym.address &= m;
 153             symtab.insert(sym);
 154         };
 155         return operate(op);
 156     }
 157
 158     SymbolTablePtr
 159     globals() const
 160     {
 161         return filterByBinding(Symbol::Binding::Global);
 162     }
 163
 164     SymbolTablePtr
 165     locals() const
 166     {
 167         return filterByBinding(Symbol::Binding::Local);
 168     }
 169
 170     SymbolTablePtr
 171     weaks() const
 172     {
 173         return filterByBinding(Symbol::Binding::Weak);
 174     }
 175
 176     void serialize(const std::string &base, CheckpointOut &cp) const;
 177     void unserialize(const std::string &base, CheckpointIn &cp,
 178                      Symbol::Binding default_binding=Symbol::Binding::Global);
 179
 180     const_iterator
 181     find(Addr address) const
 182     {
 183         AddrMap::const_iterator i = addrMap.find(address);
 184         if (i == addrMap.end())
 185             return end();
 186
 187         // There are potentially multiple symbols that map to the same
 188         // address. For simplicity, just return the first one.
 189         return symbols.begin() + i->second;
 190     }
 191
 192     const_iterator
 193     find(const std::string &name) const
 194     {
 195         NameMap::const_iterator i = nameMap.find(name);
 196         if (i == nameMap.end())
 197             return end();
 198
 199         return symbols.begin() + i->second;
 200     }
 201
 202     /// Find the nearest symbol equal to or less than the supplied
 203     /// address (e.g., the label for the enclosing function).
 204     /// @param addr     The address to look up.
 205     /// @param nextaddr Address of following symbol (for
 206     ///                 determining valid range of symbol).
 207     /// @retval A const_iterator which points to the symbol if found, or end.
 208     const_iterator
 209     findNearest(Addr addr, Addr &nextaddr) const
 210     {
 211         AddrMap::const_iterator i = addrMap.end();
 212         if (!upperBound(addr, i))
 213             return end();
 214
 215         nextaddr = i->first;
 216         --i;
 217         return symbols.begin() + i->second;
 218     }
 219
 220     /// Overload for findNearestSymbol() for callers who don't care
 221     /// about nextaddr.
 222     const_iterator
 223     findNearest(Addr addr) const
 224     {
 225         AddrMap::const_iterator i = addrMap.end();
 226         if (!upperBound(addr, i))
 227             return end();
 228
 229         --i;
 230         return symbols.begin() + i->second;
 231     }
 232 };
 233
 234 /// Global unified debugging symbol table (for target).  Conceptually
 235 /// there should be one of these per System object for full system,
 236 /// and per Process object for non-full-system, but so far one big
 237 /// global one has worked well enough.
 238 extern SymbolTable debugSymbolTable;
 239
 240 } // namespace Loader
 241
 242 #endif // __SYMTAB_HH__