llvm-6502/lib/Transforms/IPO/Internalize.cpp
2002-10-07 18:34:32 +00:00

62 lines
2.3 KiB
C++

//===-- Internalize.cpp - Mark functions internal -------------------------===//
//
// This pass loops over all of the functions in the input module, looking for a
// main function. If a main function is found, all other functions and all
// global variables with initializers are marked as internal.
//
//===----------------------------------------------------------------------===//
#include "llvm/Transforms/IPO.h"
#include "llvm/Pass.h"
#include "llvm/Module.h"
#include "Support/Statistic.h"
namespace {
Statistic<> NumFunctions("internalize", "Number of functions internalized");
Statistic<> NumGlobals ("internalize", "Number of global vars internalized");
class InternalizePass : public Pass {
virtual bool run(Module &M) {
bool FoundMain = false; // Look for a function named main...
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (I->getName() == "main" && !I->isExternal() &&
I->hasExternalLinkage()) {
FoundMain = true;
break;
}
if (!FoundMain) return false; // No main found, must be a library...
bool Changed = false;
// Found a main function, mark all functions not named main as internal.
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (I->getName() != "main" && // Leave the main function external
!I->isExternal() && // Function must be defined here
!I->hasInternalLinkage()) { // Can't already have internal linkage
I->setInternalLinkage(true);
Changed = true;
++NumFunctions;
DEBUG(std::cerr << "Internalizing func " << I->getName() << "\n");
}
// Mark all global variables with initializers as internal as well...
for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
if (!I->isExternal() && I->hasExternalLinkage()) {
I->setInternalLinkage(true);
Changed = true;
++NumGlobals;
DEBUG(std::cerr << "Internalizing gvar " << I->getName() << "\n");
}
return Changed;
}
};
RegisterOpt<InternalizePass> X("internalize", "Internalize Functions");
} // end anonymous namespace
Pass *createInternalizePass() {
return new InternalizePass();
}