llvm-6502/include/llvm/SymbolTable.h
Chris Lattner 7685ac8d35 This checkin basically amounts to a complete rewrite of the type-resolution
machinery.  This dramatically simplifies how things works, removes irritating
little corner cases, and overall improves speed and reliability.

Highlights of this change are:

1. The exponential algorithm built into the code is now gone.  For example
   the time to disassemble one bytecode file from the mesa benchmark went
   from taking 12.5s to taking 0.16s.
2. The linker bugs should be dramatically reduced.  The one remaining bug
   has to do with constant handling, which I actually introduced in
   "union-find" checkins.
3. The code is much easier to follow, as a result of fewer special cases.
   It's probably also smaller.  yaay.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@8842 91177308-0d34-0410-b5e6-96231b3b80d8
2003-10-03 18:46:24 +00:00

125 lines
4.3 KiB
C++

//===-- llvm/SymbolTable.h - Implement a type plane'd symtab ----*- C++ -*-===//
//
// This file implements a symbol table that has planed broken up by type.
// Identical types may have overlapping symbol names as long as they are
// distinct.
//
// Note that this implements a chained symbol table. If a name being 'lookup'd
// isn't found in the current symbol table, then the parent symbol table is
// searched.
//
// This chaining behavior does NOT affect iterators though: only the lookup
// method.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_SYMBOL_TABLE_H
#define LLVM_SYMBOL_TABLE_H
#include "llvm/Value.h"
#include <map>
class SymbolTable : public AbstractTypeUser,
public std::map<const Type *,
std::map<const std::string, Value *> > {
public:
typedef std::map<const std::string, Value *> VarMap;
typedef std::map<const Type *, VarMap> super;
typedef VarMap::iterator type_iterator;
typedef VarMap::const_iterator type_const_iterator;
inline SymbolTable() : InternallyInconsistent(false) {}
~SymbolTable();
// lookup - Returns null on failure...
Value *lookup(const Type *Ty, const std::string &name);
// insert - Add named definition to the symbol table...
inline void insert(Value *N) {
assert(N->hasName() && "Value must be named to go into symbol table!");
insertEntry(N->getName(), N->getType(), N);
}
void remove(Value *N);
Value *type_remove(const type_iterator &It) {
return removeEntry(find(It->second->getType()), It);
}
// insert - Insert a constant or type into the symbol table with the specified
// name... There can be a many to one mapping between names and
// (constant/type)s.
//
inline void insert(const std::string &Name, Value *V) {
assert((isa<Type>(V) || isa<Constant>(V)) &&
"Can only insert types and constants here!");
insertEntry(Name, V->getType(), V);
}
/// remove - Remove a constant or type from the symbol table with the
/// specified name.
Value *remove(const std::string &Name, Value *V) {
iterator TI = find(V->getType());
return removeEntry(TI, TI->second.find(Name));
}
// getUniqueName - Given a base name, return a string that is either equal to
// it (or derived from it) that does not already occur in the symbol table for
// the specified type.
//
std::string getUniqueName(const Type *Ty, const std::string &BaseName);
inline unsigned type_size(const Type *TypeID) const {
return find(TypeID)->second.size();
}
// Note that type_begin / type_end only work if you know that an element of
// TypeID is already in the symbol table!!!
//
inline type_iterator type_begin(const Type *TypeID) {
return find(TypeID)->second.begin();
}
inline type_const_iterator type_begin(const Type *TypeID) const {
return find(TypeID)->second.begin();
}
inline type_iterator type_end(const Type *TypeID) {
return find(TypeID)->second.end();
}
inline type_const_iterator type_end(const Type *TypeID) const {
return find(TypeID)->second.end();
}
void dump() const; // Debug method, print out symbol table
private:
// InternallyInconsistent - There are times when the symbol table is
// internally inconsistent with the rest of the program. In this one case, a
// value exists with a Name, and it's not in the symbol table. When we call
// V->setName(""), it tries to remove itself from the symbol table and dies.
// We know this is happening, and so if the flag InternallyInconsistent is
// set, removal from the symbol table is a noop.
//
bool InternallyInconsistent;
inline super::value_type operator[](const Type *Ty) {
assert(0 && "Should not use this operator to access symbol table!");
return super::value_type();
}
// insertEntry - Insert a value into the symbol table with the specified
// name...
//
void insertEntry(const std::string &Name, const Type *Ty, Value *V);
// removeEntry - Remove a value from the symbol table...
//
Value *removeEntry(iterator Plane, type_iterator Entry);
// This function is called when one of the types in the type plane are refined
virtual void refineAbstractType(const DerivedType *OldTy, const Type *NewTy);
virtual void typeBecameConcrete(const DerivedType *AbsTy);
};
#endif