//===-- Internalize.cpp - Mark functions internal -------------------------===//
//
+// The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
// 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 are marked
-// as internal.
+// 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/Internalize.h"
+#define DEBUG_TYPE "internalize"
+#include "llvm/Transforms/IPO.h"
#include "llvm/Pass.h"
#include "llvm/Module.h"
-#include "llvm/Function.h"
-#include "Support/StatisticReporter.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Compiler.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/ADT/Statistic.h"
+#include <fstream>
+#include <set>
+using namespace llvm;
-static Statistic<> NumChanged("internalize\t- Number of functions internal'd");
+STATISTIC(NumFunctions, "Number of functions internalized");
+STATISTIC(NumGlobals , "Number of global vars internalized");
namespace {
-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()) {
- FoundMain = true;
- break;
- }
-
- if (!FoundMain) return false; // No main found, must be a library...
- bool Changed = false;
+ // APIFile - A file which contains a list of symbols that should not be marked
+ // external.
+ cl::opt<std::string>
+ APIFile("internalize-public-api-file", cl::value_desc("filename"),
+ cl::desc("A file containing list of symbol names to preserve"));
- // 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->setInternalLinkage(true);
- Changed = true;
- ++NumChanged;
- }
+ // APIList - A list of symbols that should not be marked internal.
+ cl::list<std::string>
+ APIList("internalize-public-api-list", cl::value_desc("list"),
+ cl::desc("A list of symbol names to preserve"),
+ cl::CommaSeparated);
+
+ class VISIBILITY_HIDDEN InternalizePass : public ModulePass {
+ std::set<std::string> ExternalNames;
+ bool DontInternalize;
+ public:
+ static char ID; // Pass identification, replacement for typeid
+ InternalizePass(bool InternalizeEverything = true);
+ InternalizePass(const std::vector <const char *>& exportList);
+ void LoadFile(const char *Filename);
+ virtual bool runOnModule(Module &M);
+ };
+ char InternalizePass::ID = 0;
+ RegisterPass<InternalizePass> X("internalize", "Internalize Global Symbols");
+} // end anonymous namespace
- return Changed;
+InternalizePass::InternalizePass(bool InternalizeEverything)
+ : ModulePass((intptr_t)&ID), DontInternalize(false){
+ if (!APIFile.empty()) // If a filename is specified, use it
+ LoadFile(APIFile.c_str());
+ else if (!APIList.empty()) // Else, if a list is specified, use it.
+ ExternalNames.insert(APIList.begin(), APIList.end());
+ else if (!InternalizeEverything)
+ // Finally, if we're allowed to, internalize all but main.
+ DontInternalize = true;
+}
+
+InternalizePass::InternalizePass(const std::vector<const char *>&exportList)
+ : ModulePass((intptr_t)&ID), DontInternalize(false){
+ for(std::vector<const char *>::const_iterator itr = exportList.begin();
+ itr != exportList.end(); itr++) {
+ ExternalNames.insert(*itr);
}
-};
+}
-RegisterPass<InternalizePass> X("internalize", "Internalize Functions");
-} // end anonymous namespace
+void InternalizePass::LoadFile(const char *Filename) {
+ // Load the APIFile...
+ std::ifstream In(Filename);
+ if (!In.good()) {
+ cerr << "WARNING: Internalize couldn't load file '" << Filename << "'!\n";
+ return; // Do not internalize anything...
+ }
+ while (In) {
+ std::string Symbol;
+ In >> Symbol;
+ if (!Symbol.empty())
+ ExternalNames.insert(Symbol);
+ }
+}
+
+bool InternalizePass::runOnModule(Module &M) {
+ if (DontInternalize) return false;
+
+ // If no list or file of symbols was specified, check to see if there is a
+ // "main" symbol defined in the module. If so, use it, otherwise do not
+ // internalize the module, it must be a library or something.
+ //
+ if (ExternalNames.empty()) {
+ Function *MainFunc = M.getFunction("main");
+ if (MainFunc == 0 || MainFunc->isDeclaration())
+ return false; // No main found, must be a library...
+
+ // Preserve main, internalize all else.
+ ExternalNames.insert(MainFunc->getName());
+ }
+
+ 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->isDeclaration() && // Function must be defined here
+ !I->hasInternalLinkage() && // Can't already have internal linkage
+ !ExternalNames.count(I->getName())) {// Not marked to keep external?
+ I->setLinkage(GlobalValue::InternalLinkage);
+ Changed = true;
+ ++NumFunctions;
+ DOUT << "Internalizing func " << I->getName() << "\n";
+ }
+
+ // Never internalize the llvm.used symbol. It is used to implement
+ // attribute((used)).
+ ExternalNames.insert("llvm.used");
+
+ // Never internalize anchors used by the machine module info, else the info
+ // won't find them. (see MachineModuleInfo.)
+ ExternalNames.insert("llvm.dbg.compile_units");
+ ExternalNames.insert("llvm.dbg.global_variables");
+ ExternalNames.insert("llvm.dbg.subprograms");
+
+ // Mark all global variables with initializers as internal as well.
+ for (Module::global_iterator I = M.global_begin(), E = M.global_end();
+ I != E; ++I)
+ if (!I->isDeclaration() && !I->hasInternalLinkage() &&
+ !ExternalNames.count(I->getName())) {
+ // Special case handling of the global ctor and dtor list. When we
+ // internalize it, we mark it constant, which allows elimination of
+ // the list if it's empty.
+ //
+ if (I->hasAppendingLinkage() && (I->getName() == "llvm.global_ctors" ||
+ I->getName() == "llvm.global_dtors")) {
+ // If the global ctors/dtors list has no uses, do not internalize it, as
+ // there is no __main in this program, so the asmprinter should handle
+ // it.
+ if (I->use_empty()) continue;
+
+ // Otherwise, also mark the list constant, as we know that it will not
+ // be mutated any longer, and the makes simple IPO xforms automatically
+ // better.
+ I->setConstant(true);
+ }
+
+ I->setLinkage(GlobalValue::InternalLinkage);
+ Changed = true;
+ ++NumGlobals;
+ DOUT << "Internalized gvar " << I->getName() << "\n";
+ }
+
+ return Changed;
+}
+
+ModulePass *llvm::createInternalizePass(bool InternalizeEverything) {
+ return new InternalizePass(InternalizeEverything);
+}
-Pass *createInternalizePass() {
- return new InternalizePass();
+ModulePass *llvm::createInternalizePass(const std::vector <const char *> &el) {
+ return new InternalizePass(el);
}
projects / oota-llvm.git / blobdiff