bool InternalizePass::runOnModule(Module &M) { CallGraph *CG = getAnalysisIfAvailable<CallGraph>(); CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0; bool Changed = false; // Never internalize functions which code-gen might insert. // FIXME: We should probably add this (and the __stack_chk_guard) via some // type of call-back in CodeGen. ExternalNames.insert("__stack_chk_fail"); // Mark all functions not in the api as internal. // FIXME: maybe use private linkage? for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (!I->isDeclaration() && // Function must be defined here // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !I->hasLocalLinkage() && // Can't already have internal linkage !ExternalNames.count(I->getName())) {// Not marked to keep external? I->setLinkage(GlobalValue::InternalLinkage); // Remove a callgraph edge from the external node to this function. if (ExternalNode) ExternalNode->removeOneAbstractEdgeTo((*CG)[I]); Changed = true; ++NumFunctions; DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n"); } // Never internalize the llvm.used symbol. It is used to implement // attribute((used)). // FIXME: Shouldn't this just filter on llvm.metadata section?? ExternalNames.insert("llvm.used"); ExternalNames.insert("llvm.compiler.used"); // Never internalize anchors used by the machine module info, else the info // won't find them. (see MachineModuleInfo.) ExternalNames.insert("llvm.global_ctors"); ExternalNames.insert("llvm.global_dtors"); ExternalNames.insert("llvm.global.annotations"); // Never internalize symbols code-gen inserts. ExternalNames.insert("__stack_chk_guard"); // Mark all global variables with initializers that are not in the api as // internal as well. // FIXME: maybe use private linkage? for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasLocalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumGlobals; DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n"); } // Mark all aliases that are not in the api as internal as well. for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasInternalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumAliases; DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n"); } return Changed; }
bool InternalizePass::runOnModule(Module &M) { CallGraph *CG = getAnalysisIfAvailable<CallGraph>(); CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0; if (ExternalNames.empty()) { // Return if we're not in 'all but main' mode and have no external api if (!AllButMain) 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. // 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; // Never internalize functions which code-gen might insert. ExternalNames.insert("__stack_chk_fail"); // Mark all functions not in the api as internal. // FIXME: maybe use private linkage? for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) if (!I->isDeclaration() && // Function must be defined here // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !I->hasLocalLinkage() && // Can't already have internal linkage !ExternalNames.count(I->getName())) {// Not marked to keep external? I->setLinkage(GlobalValue::InternalLinkage); // Remove a callgraph edge from the external node to this function. if (ExternalNode) ExternalNode->removeOneAbstractEdgeTo((*CG)[I]); Changed = true; ++NumFunctions; DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n"); } // Never internalize the llvm.used symbol. It is used to implement // attribute((used)). // FIXME: Shouldn't this just filter on llvm.metadata section?? ExternalNames.insert("llvm.used"); ExternalNames.insert("llvm.compiler.used"); // Never internalize anchors used by the machine module info, else the info // won't find them. (see MachineModuleInfo.) ExternalNames.insert("llvm.global_ctors"); ExternalNames.insert("llvm.global_dtors"); ExternalNames.insert("llvm.global.annotations"); // Never internalize symbols code-gen inserts. ExternalNames.insert("__stack_chk_guard"); // Mark all global variables with initializers that are not in the api as // internal as well. // FIXME: maybe use private linkage? for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasLocalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumGlobals; DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n"); } // Mark all aliases that are not in the api as internal as well. for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end(); I != E; ++I) if (!I->isDeclaration() && !I->hasInternalLinkage() && // Available externally is really just a "declaration with a body". !I->hasAvailableExternallyLinkage() && !ExternalNames.count(I->getName())) { I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumAliases; DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n"); } return Changed; }
bool InternalizePass::runOnModule(Module &M) { CallGraphWrapperPass *CGPass = getAnalysisIfAvailable<CallGraphWrapperPass>(); CallGraph *CG = CGPass ? &CGPass->getCallGraph() : 0; CallGraphNode *ExternalNode = CG ? CG->getExternalCallingNode() : 0; bool Changed = false; SmallPtrSet<GlobalValue *, 8> Used; collectUsedGlobalVariables(M, Used, false); // We must assume that globals in llvm.used have a reference that not even // the linker can see, so we don't internalize them. // For llvm.compiler.used the situation is a bit fuzzy. The assembler and // linker can drop those symbols. If this pass is running as part of LTO, // one might think that it could just drop llvm.compiler.used. The problem // is that even in LTO llvm doesn't see every reference. For example, // we don't see references from function local inline assembly. To be // conservative, we internalize symbols in llvm.compiler.used, but we // keep llvm.compiler.used so that the symbol is not deleted by llvm. for (SmallPtrSet<GlobalValue *, 8>::iterator I = Used.begin(), E = Used.end(); I != E; ++I) { GlobalValue *V = *I; ExternalNames.insert(V->getName()); } // Mark all functions not in the api as internal. for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) { if (!shouldInternalize(*I, ExternalNames, OnlyHidden)) continue; I->setLinkage(GlobalValue::InternalLinkage); if (ExternalNode) // Remove a callgraph edge from the external node to this function. ExternalNode->removeOneAbstractEdgeTo((*CG)[I]); Changed = true; ++NumFunctions; DEBUG(dbgs() << "Internalizing func " << I->getName() << "\n"); } // Never internalize the llvm.used symbol. It is used to implement // attribute((used)). // FIXME: Shouldn't this just filter on llvm.metadata section?? ExternalNames.insert("llvm.used"); ExternalNames.insert("llvm.compiler.used"); // Never internalize anchors used by the machine module info, else the info // won't find them. (see MachineModuleInfo.) ExternalNames.insert("llvm.global_ctors"); ExternalNames.insert("llvm.global_dtors"); ExternalNames.insert("llvm.global.annotations"); // Never internalize symbols code-gen inserts. // FIXME: We should probably add this (and the __stack_chk_guard) via some // type of call-back in CodeGen. ExternalNames.insert("__stack_chk_fail"); ExternalNames.insert("__stack_chk_guard"); // Mark all global variables with initializers that are not in the api as // internal as well. for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; ++I) { if (!shouldInternalize(*I, ExternalNames, OnlyHidden)) continue; I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumGlobals; DEBUG(dbgs() << "Internalized gvar " << I->getName() << "\n"); } // Mark all aliases that are not in the api as internal as well. for (Module::alias_iterator I = M.alias_begin(), E = M.alias_end(); I != E; ++I) { if (!shouldInternalize(*I, ExternalNames, OnlyHidden)) continue; I->setLinkage(GlobalValue::InternalLinkage); Changed = true; ++NumAliases; DEBUG(dbgs() << "Internalized alias " << I->getName() << "\n"); } return Changed; }