1 //===-- Internalize.cpp - Mark functions internal -------------------------===//
3 // This pass loops over all of the functions in the input module, looking for a
4 // main function. If a main function is found, all other functions and all
5 // global variables with initializers are marked as internal.
7 //===----------------------------------------------------------------------===//
9 #include "llvm/Transforms/IPO.h"
10 #include "llvm/Pass.h"
11 #include "llvm/Module.h"
12 #include "Support/StatisticReporter.h"
15 Statistic<> NumFunctions("internalize\t- Number of functions internalized");
16 Statistic<> NumGlobals ("internalize\t- Number of global vars internalized");
19 class InternalizePass : public Pass {
20 virtual bool run(Module &M) {
21 bool FoundMain = false; // Look for a function named main...
22 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
23 if (I->getName() == "main" && !I->isExternal() &&
24 I->hasExternalLinkage()) {
29 if (!FoundMain) return false; // No main found, must be a library...
33 // Found a main function, mark all functions not named main as internal.
34 for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
35 if (I->getName() != "main" && // Leave the main function external
36 !I->isExternal() && // Function must be defined here
37 !I->hasInternalLinkage()) { // Can't already have internal linkage
38 I->setInternalLinkage(true);
41 DEBUG(std::cerr << "Internalizing func " << I->getName() << "\n");
44 // Mark all global variables with initializers as internal as well...
45 for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
46 if (I->hasInitializer() && I->hasExternalLinkage()) {
47 I->setInternalLinkage(true);
50 DEBUG(std::cerr << "Internalizing gvar " << I->getName() << "\n");
57 RegisterOpt<InternalizePass> X("internalize", "Internalize Functions");
58 } // end anonymous namespace
60 Pass *createInternalizePass() {
61 return new InternalizePass();