+/// getOrInsertGlobal - Look up the specified global in the module symbol table.
+/// 1. If it does not exist, add a declaration of the global and return it.
+/// 2. Else, the global exists but has the wrong type: return the function
+/// with a constantexpr cast to the right type.
+/// 3. Finally, if the existing global is the correct delclaration, return the
+/// existing global.
+Constant *Module::getOrInsertGlobal(const std::string &Name, const Type *Ty) {
+ ValueSymbolTable &SymTab = getValueSymbolTable();
+
+ // See if we have a definition for the specified global already.
+ GlobalVariable *GV = dyn_cast_or_null<GlobalVariable>(SymTab.lookup(Name));
+ if (GV == 0) {
+ // Nope, add it
+ GlobalVariable *New =
+ new GlobalVariable(Ty, false, GlobalVariable::ExternalLinkage, 0, Name);
+ GlobalList.push_back(New);
+ return New; // Return the new declaration.
+ }
+
+ // If the variable exists but has the wrong type, return a bitcast to the
+ // right type.
+ if (GV->getType() != PointerType::getUnqual(Ty))
+ return ConstantExpr::getBitCast(GV, PointerType::getUnqual(Ty));
+
+ // Otherwise, we just found the existing function or a prototype.
+ return GV;
+}
+
+//===----------------------------------------------------------------------===//
+// Methods for easy access to the global variables in the module.
+//
+
+// getNamedAlias - Look up the specified global in the module symbol table.
+// If it does not exist, return null.
+//
+GlobalAlias *Module::getNamedAlias(const std::string &Name) const {
+ const ValueSymbolTable &SymTab = getValueSymbolTable();
+ return dyn_cast_or_null<GlobalAlias>(SymTab.lookup(Name));
+}
+