llvm-project/llvm/lib/VMCore/Module.cpp

146 lines
4.9 KiB
C++

//===-- Module.cpp - Implement the Module class ------------------*- C++ -*--=//
//
// This file implements the Module class for the VMCore library.
//
//===----------------------------------------------------------------------===//
#include "llvm/Module.h"
#include "llvm/Function.h"
#include "llvm/GlobalVariable.h"
#include "llvm/InstrTypes.h"
#include "llvm/ValueHolderImpl.h"
#include "llvm/Type.h"
#include "llvm/ConstantVals.h"
#include "llvm/DerivedTypes.h"
#include "Support/STLExtras.h"
#include <map>
// Instantiate Templates - This ugliness is the price we have to pay
// for having a DefHolderImpl.h file seperate from DefHolder.h! :(
//
template class ValueHolder<GlobalVariable, Module, Module>;
template class ValueHolder<Function, Module, Module>;
// Define the GlobalValueRefMap as a struct that wraps a map so that we don't
// have Module.h depend on <map>
//
struct GlobalValueRefMap : public std::map<GlobalValue*, ConstantPointerRef*>{
};
Module::Module()
: Value(Type::VoidTy, Value::ModuleVal, ""), SymTabValue(this),
GlobalList(this, this), FunctionList(this, this), GVRefMap(0) {
}
Module::~Module() {
dropAllReferences();
GlobalList.delete_all();
GlobalList.setParent(0);
FunctionList.delete_all();
FunctionList.setParent(0);
}
// getOrInsertFunction - Look up the specified function in the module symbol
// table. If it does not exist, add a prototype for the function and return
// it. This is nice because it allows most passes to get away with not handling
// the symbol table directly for this common task.
//
Function *Module::getOrInsertFunction(const std::string &Name,
const FunctionType *Ty) {
SymbolTable *SymTab = getSymbolTableSure();
// See if we have a definitions for the specified function already...
if (Value *V = SymTab->lookup(PointerType::get(Ty), Name)) {
return cast<Function>(V); // Yup, got it
} else { // Nope, add one
Function *New = new Function(Ty, false, Name);
FunctionList.push_back(New);
return New; // Return the new prototype...
}
}
// getFunction - Look up the specified function in the module symbol table.
// If it does not exist, return null.
//
Function *Module::getFunction(const std::string &Name, const FunctionType *Ty) {
SymbolTable *SymTab = getSymbolTable();
if (SymTab == 0) return 0; // No symtab, no symbols...
return cast_or_null<Function>(SymTab->lookup(PointerType::get(Ty), Name));
}
// addTypeName - Insert an entry in the symbol table mapping Str to Type. If
// there is already an entry for this name, true is returned and the symbol
// table is not modified.
//
bool Module::addTypeName(const std::string &Name, const Type *Ty) {
SymbolTable *ST = getSymbolTableSure();
if (ST->lookup(Type::TypeTy, Name)) return true; // Already in symtab...
// Not in symbol table? Set the name with the Symtab as an argument so the
// type knows what to update...
((Value*)Ty)->setName(Name, ST);
return false;
}
// dropAllReferences() - This function causes all the subinstructions to "let
// go" of all references that they are maintaining. This allows one to
// 'delete' a whole class at a time, even though there may be circular
// references... first all references are dropped, and all use counts go to
// zero. Then everything is delete'd for real. Note that no operations are
// valid on an object that has "dropped all references", except operator
// delete.
//
void Module::dropAllReferences() {
for_each(FunctionList.begin(), FunctionList.end(),
std::mem_fun(&Function::dropAllReferences));
for_each(GlobalList.begin(), GlobalList.end(),
std::mem_fun(&GlobalVariable::dropAllReferences));
// If there are any GlobalVariable references still out there, nuke them now.
// Since all references are hereby dropped, nothing could possibly reference
// them still.
if (GVRefMap) {
for (GlobalValueRefMap::iterator I = GVRefMap->begin(), E = GVRefMap->end();
I != E; ++I) {
// Delete the ConstantPointerRef node...
I->second->destroyConstant();
}
// Since the table is empty, we can now delete it...
delete GVRefMap;
}
}
// Accessor for the underlying GlobalValRefMap...
ConstantPointerRef *Module::getConstantPointerRef(GlobalValue *V){
// Create ref map lazily on demand...
if (GVRefMap == 0) GVRefMap = new GlobalValueRefMap();
GlobalValueRefMap::iterator I = GVRefMap->find(V);
if (I != GVRefMap->end()) return I->second;
ConstantPointerRef *Ref = new ConstantPointerRef(V);
GVRefMap->insert(std::make_pair(V, Ref));
return Ref;
}
void Module::mutateConstantPointerRef(GlobalValue *OldGV, GlobalValue *NewGV) {
GlobalValueRefMap::iterator I = GVRefMap->find(OldGV);
assert(I != GVRefMap->end() &&
"mutateConstantPointerRef; OldGV not in table!");
ConstantPointerRef *Ref = I->second;
// Remove the old entry...
GVRefMap->erase(I);
// Insert the new entry...
GVRefMap->insert(std::make_pair(NewGV, Ref));
}