diff options
Diffstat (limited to 'contrib/llvm/lib/Analysis/IPA')
| -rw-r--r-- | contrib/llvm/lib/Analysis/IPA/CallGraph.cpp | 302 | ||||
| -rw-r--r-- | contrib/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp | 632 | ||||
| -rw-r--r-- | contrib/llvm/lib/Analysis/IPA/CallPrinter.cpp | 92 | ||||
| -rw-r--r-- | contrib/llvm/lib/Analysis/IPA/GlobalsModRef.cpp | 609 | ||||
| -rw-r--r-- | contrib/llvm/lib/Analysis/IPA/IPA.cpp | 30 | ||||
| -rw-r--r-- | contrib/llvm/lib/Analysis/IPA/InlineCost.cpp | 1437 |
6 files changed, 0 insertions, 3102 deletions
diff --git a/contrib/llvm/lib/Analysis/IPA/CallGraph.cpp b/contrib/llvm/lib/Analysis/IPA/CallGraph.cpp deleted file mode 100644 index e2799d9..0000000 --- a/contrib/llvm/lib/Analysis/IPA/CallGraph.cpp +++ /dev/null @@ -1,302 +0,0 @@ -//===- CallGraph.cpp - Build a Module's call graph ------------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// - -#include "llvm/Analysis/CallGraph.h" -#include "llvm/IR/CallSite.h" -#include "llvm/IR/Instructions.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/Module.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/raw_ostream.h" -using namespace llvm; - -//===----------------------------------------------------------------------===// -// Implementations of the CallGraph class methods. -// - -CallGraph::CallGraph(Module &M) - : M(M), Root(nullptr), ExternalCallingNode(getOrInsertFunction(nullptr)), - CallsExternalNode(new CallGraphNode(nullptr)) { - // Add every function to the call graph. - for (Function &F : M) - addToCallGraph(&F); - - // If we didn't find a main function, use the external call graph node - if (!Root) - Root = ExternalCallingNode; -} - -CallGraph::~CallGraph() { - // CallsExternalNode is not in the function map, delete it explicitly. - CallsExternalNode->allReferencesDropped(); - delete CallsExternalNode; - -// Reset all node's use counts to zero before deleting them to prevent an -// assertion from firing. -#ifndef NDEBUG - for (auto &I : FunctionMap) - I.second->allReferencesDropped(); -#endif - for (auto &I : FunctionMap) - delete I.second; -} - -void CallGraph::addToCallGraph(Function *F) { - CallGraphNode *Node = getOrInsertFunction(F); - - // If this function has external linkage, anything could call it. - if (!F->hasLocalLinkage()) { - ExternalCallingNode->addCalledFunction(CallSite(), Node); - - // Found the entry point? - if (F->getName() == "main") { - if (Root) // Found multiple external mains? Don't pick one. - Root = ExternalCallingNode; - else - Root = Node; // Found a main, keep track of it! - } - } - - // If this function has its address taken, anything could call it. - if (F->hasAddressTaken()) - ExternalCallingNode->addCalledFunction(CallSite(), Node); - - // If this function is not defined in this translation unit, it could call - // anything. - if (F->isDeclaration() && !F->isIntrinsic()) - Node->addCalledFunction(CallSite(), CallsExternalNode); - - // Look for calls by this function. - for (Function::iterator BB = F->begin(), BBE = F->end(); BB != BBE; ++BB) - for (BasicBlock::iterator II = BB->begin(), IE = BB->end(); II != IE; - ++II) { - CallSite CS(cast<Value>(II)); - if (CS) { - const Function *Callee = CS.getCalledFunction(); - if (!Callee || !Intrinsic::isLeaf(Callee->getIntrinsicID())) - // Indirect calls of intrinsics are not allowed so no need to check. - // We can be more precise here by using TargetArg returned by - // Intrinsic::isLeaf. - Node->addCalledFunction(CS, CallsExternalNode); - else if (!Callee->isIntrinsic()) - Node->addCalledFunction(CS, getOrInsertFunction(Callee)); - } - } -} - -void CallGraph::print(raw_ostream &OS) const { - OS << "CallGraph Root is: "; - if (Function *F = Root->getFunction()) - OS << F->getName() << "\n"; - else { - OS << "<<null function: 0x" << Root << ">>\n"; - } - - // Print in a deterministic order by sorting CallGraphNodes by name. We do - // this here to avoid slowing down the non-printing fast path. - - SmallVector<CallGraphNode *, 16> Nodes; - Nodes.reserve(FunctionMap.size()); - - for (auto I = begin(), E = end(); I != E; ++I) - Nodes.push_back(I->second); - - std::sort(Nodes.begin(), Nodes.end(), - [](CallGraphNode *LHS, CallGraphNode *RHS) { - if (Function *LF = LHS->getFunction()) - if (Function *RF = RHS->getFunction()) - return LF->getName() < RF->getName(); - - return RHS->getFunction() != nullptr; - }); - - for (CallGraphNode *CN : Nodes) - CN->print(OS); -} - -#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) -void CallGraph::dump() const { print(dbgs()); } -#endif - -// removeFunctionFromModule - Unlink the function from this module, returning -// it. Because this removes the function from the module, the call graph node -// is destroyed. This is only valid if the function does not call any other -// functions (ie, there are no edges in it's CGN). The easiest way to do this -// is to dropAllReferences before calling this. -// -Function *CallGraph::removeFunctionFromModule(CallGraphNode *CGN) { - assert(CGN->empty() && "Cannot remove function from call " - "graph if it references other functions!"); - Function *F = CGN->getFunction(); // Get the function for the call graph node - delete CGN; // Delete the call graph node for this func - FunctionMap.erase(F); // Remove the call graph node from the map - - M.getFunctionList().remove(F); - return F; -} - -/// spliceFunction - Replace the function represented by this node by another. -/// This does not rescan the body of the function, so it is suitable when -/// splicing the body of the old function to the new while also updating all -/// callers from old to new. -/// -void CallGraph::spliceFunction(const Function *From, const Function *To) { - assert(FunctionMap.count(From) && "No CallGraphNode for function!"); - assert(!FunctionMap.count(To) && - "Pointing CallGraphNode at a function that already exists"); - FunctionMapTy::iterator I = FunctionMap.find(From); - I->second->F = const_cast<Function*>(To); - FunctionMap[To] = I->second; - FunctionMap.erase(I); -} - -// getOrInsertFunction - This method is identical to calling operator[], but -// it will insert a new CallGraphNode for the specified function if one does -// not already exist. -CallGraphNode *CallGraph::getOrInsertFunction(const Function *F) { - CallGraphNode *&CGN = FunctionMap[F]; - if (CGN) - return CGN; - - assert((!F || F->getParent() == &M) && "Function not in current module!"); - return CGN = new CallGraphNode(const_cast<Function*>(F)); -} - -//===----------------------------------------------------------------------===// -// Implementations of the CallGraphNode class methods. -// - -void CallGraphNode::print(raw_ostream &OS) const { - if (Function *F = getFunction()) - OS << "Call graph node for function: '" << F->getName() << "'"; - else - OS << "Call graph node <<null function>>"; - - OS << "<<" << this << ">> #uses=" << getNumReferences() << '\n'; - - for (const_iterator I = begin(), E = end(); I != E; ++I) { - OS << " CS<" << I->first << "> calls "; - if (Function *FI = I->second->getFunction()) - OS << "function '" << FI->getName() <<"'\n"; - else - OS << "external node\n"; - } - OS << '\n'; -} - -#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) -void CallGraphNode::dump() const { print(dbgs()); } -#endif - -/// removeCallEdgeFor - This method removes the edge in the node for the -/// specified call site. Note that this method takes linear time, so it -/// should be used sparingly. -void CallGraphNode::removeCallEdgeFor(CallSite CS) { - for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) { - assert(I != CalledFunctions.end() && "Cannot find callsite to remove!"); - if (I->first == CS.getInstruction()) { - I->second->DropRef(); - *I = CalledFunctions.back(); - CalledFunctions.pop_back(); - return; - } - } -} - -// removeAnyCallEdgeTo - This method removes any call edges from this node to -// the specified callee function. This takes more time to execute than -// removeCallEdgeTo, so it should not be used unless necessary. -void CallGraphNode::removeAnyCallEdgeTo(CallGraphNode *Callee) { - for (unsigned i = 0, e = CalledFunctions.size(); i != e; ++i) - if (CalledFunctions[i].second == Callee) { - Callee->DropRef(); - CalledFunctions[i] = CalledFunctions.back(); - CalledFunctions.pop_back(); - --i; --e; - } -} - -/// removeOneAbstractEdgeTo - Remove one edge associated with a null callsite -/// from this node to the specified callee function. -void CallGraphNode::removeOneAbstractEdgeTo(CallGraphNode *Callee) { - for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) { - assert(I != CalledFunctions.end() && "Cannot find callee to remove!"); - CallRecord &CR = *I; - if (CR.second == Callee && CR.first == nullptr) { - Callee->DropRef(); - *I = CalledFunctions.back(); - CalledFunctions.pop_back(); - return; - } - } -} - -/// replaceCallEdge - This method replaces the edge in the node for the -/// specified call site with a new one. Note that this method takes linear -/// time, so it should be used sparingly. -void CallGraphNode::replaceCallEdge(CallSite CS, - CallSite NewCS, CallGraphNode *NewNode){ - for (CalledFunctionsVector::iterator I = CalledFunctions.begin(); ; ++I) { - assert(I != CalledFunctions.end() && "Cannot find callsite to remove!"); - if (I->first == CS.getInstruction()) { - I->second->DropRef(); - I->first = NewCS.getInstruction(); - I->second = NewNode; - NewNode->AddRef(); - return; - } - } -} - -//===----------------------------------------------------------------------===// -// Out-of-line definitions of CallGraphAnalysis class members. -// - -char CallGraphAnalysis::PassID; - -//===----------------------------------------------------------------------===// -// Implementations of the CallGraphWrapperPass class methods. -// - -CallGraphWrapperPass::CallGraphWrapperPass() : ModulePass(ID) { - initializeCallGraphWrapperPassPass(*PassRegistry::getPassRegistry()); -} - -CallGraphWrapperPass::~CallGraphWrapperPass() {} - -void CallGraphWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const { - AU.setPreservesAll(); -} - -bool CallGraphWrapperPass::runOnModule(Module &M) { - // All the real work is done in the constructor for the CallGraph. - G.reset(new CallGraph(M)); - return false; -} - -INITIALIZE_PASS(CallGraphWrapperPass, "basiccg", "CallGraph Construction", - false, true) - -char CallGraphWrapperPass::ID = 0; - -void CallGraphWrapperPass::releaseMemory() { G.reset(); } - -void CallGraphWrapperPass::print(raw_ostream &OS, const Module *) const { - if (!G) { - OS << "No call graph has been built!\n"; - return; - } - - // Just delegate. - G->print(OS); -} - -#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) -void CallGraphWrapperPass::dump() const { print(dbgs(), nullptr); } -#endif diff --git a/contrib/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp b/contrib/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp deleted file mode 100644 index 07b389a..0000000 --- a/contrib/llvm/lib/Analysis/IPA/CallGraphSCCPass.cpp +++ /dev/null @@ -1,632 +0,0 @@ -//===- CallGraphSCCPass.cpp - Pass that operates BU on call graph ---------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the CallGraphSCCPass class, which is used for passes -// which are implemented as bottom-up traversals on the call graph. Because -// there may be cycles in the call graph, passes of this type operate on the -// call-graph in SCC order: that is, they process function bottom-up, except for -// recursive functions, which they process all at once. -// -//===----------------------------------------------------------------------===// - -#include "llvm/Analysis/CallGraphSCCPass.h" -#include "llvm/ADT/SCCIterator.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/Analysis/CallGraph.h" -#include "llvm/IR/Function.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/LLVMContext.h" -#include "llvm/IR/LegacyPassManagers.h" -#include "llvm/Support/CommandLine.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/Timer.h" -#include "llvm/Support/raw_ostream.h" -using namespace llvm; - -#define DEBUG_TYPE "cgscc-passmgr" - -static cl::opt<unsigned> -MaxIterations("max-cg-scc-iterations", cl::ReallyHidden, cl::init(4)); - -STATISTIC(MaxSCCIterations, "Maximum CGSCCPassMgr iterations on one SCC"); - -//===----------------------------------------------------------------------===// -// CGPassManager -// -/// CGPassManager manages FPPassManagers and CallGraphSCCPasses. - -namespace { - -class CGPassManager : public ModulePass, public PMDataManager { -public: - static char ID; - explicit CGPassManager() - : ModulePass(ID), PMDataManager() { } - - /// Execute all of the passes scheduled for execution. Keep track of - /// whether any of the passes modifies the module, and if so, return true. - bool runOnModule(Module &M) override; - - using ModulePass::doInitialization; - using ModulePass::doFinalization; - - bool doInitialization(CallGraph &CG); - bool doFinalization(CallGraph &CG); - - /// Pass Manager itself does not invalidate any analysis info. - void getAnalysisUsage(AnalysisUsage &Info) const override { - // CGPassManager walks SCC and it needs CallGraph. - Info.addRequired<CallGraphWrapperPass>(); - Info.setPreservesAll(); - } - - const char *getPassName() const override { - return "CallGraph Pass Manager"; - } - - PMDataManager *getAsPMDataManager() override { return this; } - Pass *getAsPass() override { return this; } - - // Print passes managed by this manager - void dumpPassStructure(unsigned Offset) override { - errs().indent(Offset*2) << "Call Graph SCC Pass Manager\n"; - for (unsigned Index = 0; Index < getNumContainedPasses(); ++Index) { - Pass *P = getContainedPass(Index); - P->dumpPassStructure(Offset + 1); - dumpLastUses(P, Offset+1); - } - } - - Pass *getContainedPass(unsigned N) { - assert(N < PassVector.size() && "Pass number out of range!"); - return static_cast<Pass *>(PassVector[N]); - } - - PassManagerType getPassManagerType() const override { - return PMT_CallGraphPassManager; - } - -private: - bool RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG, - bool &DevirtualizedCall); - - bool RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC, - CallGraph &CG, bool &CallGraphUpToDate, - bool &DevirtualizedCall); - bool RefreshCallGraph(CallGraphSCC &CurSCC, CallGraph &CG, - bool IsCheckingMode); -}; - -} // end anonymous namespace. - -char CGPassManager::ID = 0; - - -bool CGPassManager::RunPassOnSCC(Pass *P, CallGraphSCC &CurSCC, - CallGraph &CG, bool &CallGraphUpToDate, - bool &DevirtualizedCall) { - bool Changed = false; - PMDataManager *PM = P->getAsPMDataManager(); - - if (!PM) { - CallGraphSCCPass *CGSP = (CallGraphSCCPass*)P; - if (!CallGraphUpToDate) { - DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false); - CallGraphUpToDate = true; - } - - { - TimeRegion PassTimer(getPassTimer(CGSP)); - Changed = CGSP->runOnSCC(CurSCC); - } - - // After the CGSCCPass is done, when assertions are enabled, use - // RefreshCallGraph to verify that the callgraph was correctly updated. -#ifndef NDEBUG - if (Changed) - RefreshCallGraph(CurSCC, CG, true); -#endif - - return Changed; - } - - - assert(PM->getPassManagerType() == PMT_FunctionPassManager && - "Invalid CGPassManager member"); - FPPassManager *FPP = (FPPassManager*)P; - - // Run pass P on all functions in the current SCC. - for (CallGraphNode *CGN : CurSCC) { - if (Function *F = CGN->getFunction()) { - dumpPassInfo(P, EXECUTION_MSG, ON_FUNCTION_MSG, F->getName()); - { - TimeRegion PassTimer(getPassTimer(FPP)); - Changed |= FPP->runOnFunction(*F); - } - F->getContext().yield(); - } - } - - // The function pass(es) modified the IR, they may have clobbered the - // callgraph. - if (Changed && CallGraphUpToDate) { - DEBUG(dbgs() << "CGSCCPASSMGR: Pass Dirtied SCC: " - << P->getPassName() << '\n'); - CallGraphUpToDate = false; - } - return Changed; -} - - -/// Scan the functions in the specified CFG and resync the -/// callgraph with the call sites found in it. This is used after -/// FunctionPasses have potentially munged the callgraph, and can be used after -/// CallGraphSCC passes to verify that they correctly updated the callgraph. -/// -/// This function returns true if it devirtualized an existing function call, -/// meaning it turned an indirect call into a direct call. This happens when -/// a function pass like GVN optimizes away stuff feeding the indirect call. -/// This never happens in checking mode. -/// -bool CGPassManager::RefreshCallGraph(CallGraphSCC &CurSCC, - CallGraph &CG, bool CheckingMode) { - DenseMap<Value*, CallGraphNode*> CallSites; - - DEBUG(dbgs() << "CGSCCPASSMGR: Refreshing SCC with " << CurSCC.size() - << " nodes:\n"; - for (CallGraphNode *CGN : CurSCC) - CGN->dump(); - ); - - bool MadeChange = false; - bool DevirtualizedCall = false; - - // Scan all functions in the SCC. - unsigned FunctionNo = 0; - for (CallGraphSCC::iterator SCCIdx = CurSCC.begin(), E = CurSCC.end(); - SCCIdx != E; ++SCCIdx, ++FunctionNo) { - CallGraphNode *CGN = *SCCIdx; - Function *F = CGN->getFunction(); - if (!F || F->isDeclaration()) continue; - - // Walk the function body looking for call sites. Sync up the call sites in - // CGN with those actually in the function. - - // Keep track of the number of direct and indirect calls that were - // invalidated and removed. - unsigned NumDirectRemoved = 0, NumIndirectRemoved = 0; - - // Get the set of call sites currently in the function. - for (CallGraphNode::iterator I = CGN->begin(), E = CGN->end(); I != E; ) { - // If this call site is null, then the function pass deleted the call - // entirely and the WeakVH nulled it out. - if (!I->first || - // If we've already seen this call site, then the FunctionPass RAUW'd - // one call with another, which resulted in two "uses" in the edge - // list of the same call. - CallSites.count(I->first) || - - // If the call edge is not from a call or invoke, or it is a - // instrinsic call, then the function pass RAUW'd a call with - // another value. This can happen when constant folding happens - // of well known functions etc. - !CallSite(I->first) || - (CallSite(I->first).getCalledFunction() && - CallSite(I->first).getCalledFunction()->isIntrinsic() && - Intrinsic::isLeaf( - CallSite(I->first).getCalledFunction()->getIntrinsicID()))) { - assert(!CheckingMode && - "CallGraphSCCPass did not update the CallGraph correctly!"); - - // If this was an indirect call site, count it. - if (!I->second->getFunction()) - ++NumIndirectRemoved; - else - ++NumDirectRemoved; - - // Just remove the edge from the set of callees, keep track of whether - // I points to the last element of the vector. - bool WasLast = I + 1 == E; - CGN->removeCallEdge(I); - - // If I pointed to the last element of the vector, we have to bail out: - // iterator checking rejects comparisons of the resultant pointer with - // end. - if (WasLast) - break; - E = CGN->end(); - continue; - } - - assert(!CallSites.count(I->first) && - "Call site occurs in node multiple times"); - - CallSite CS(I->first); - if (CS) { - Function *Callee = CS.getCalledFunction(); - // Ignore intrinsics because they're not really function calls. - if (!Callee || !(Callee->isIntrinsic())) - CallSites.insert(std::make_pair(I->first, I->second)); - } - ++I; - } - - // Loop over all of the instructions in the function, getting the callsites. - // Keep track of the number of direct/indirect calls added. - unsigned NumDirectAdded = 0, NumIndirectAdded = 0; - - for (Function::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) - for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) { - CallSite CS(cast<Value>(I)); - if (!CS) continue; - Function *Callee = CS.getCalledFunction(); - if (Callee && Callee->isIntrinsic()) continue; - - // If this call site already existed in the callgraph, just verify it - // matches up to expectations and remove it from CallSites. - DenseMap<Value*, CallGraphNode*>::iterator ExistingIt = - CallSites.find(CS.getInstruction()); - if (ExistingIt != CallSites.end()) { - CallGraphNode *ExistingNode = ExistingIt->second; - - // Remove from CallSites since we have now seen it. - CallSites.erase(ExistingIt); - - // Verify that the callee is right. - if (ExistingNode->getFunction() == CS.getCalledFunction()) - continue; - - // If we are in checking mode, we are not allowed to actually mutate - // the callgraph. If this is a case where we can infer that the - // callgraph is less precise than it could be (e.g. an indirect call - // site could be turned direct), don't reject it in checking mode, and - // don't tweak it to be more precise. - if (CheckingMode && CS.getCalledFunction() && - ExistingNode->getFunction() == nullptr) - continue; - - assert(!CheckingMode && - "CallGraphSCCPass did not update the CallGraph correctly!"); - - // If not, we either went from a direct call to indirect, indirect to - // direct, or direct to different direct. - CallGraphNode *CalleeNode; - if (Function *Callee = CS.getCalledFunction()) { - CalleeNode = CG.getOrInsertFunction(Callee); - // Keep track of whether we turned an indirect call into a direct - // one. - if (!ExistingNode->getFunction()) { - DevirtualizedCall = true; - DEBUG(dbgs() << " CGSCCPASSMGR: Devirtualized call to '" - << Callee->getName() << "'\n"); - } - } else { - CalleeNode = CG.getCallsExternalNode(); - } - - // Update the edge target in CGN. - CGN->replaceCallEdge(CS, CS, CalleeNode); - MadeChange = true; - continue; - } - - assert(!CheckingMode && - "CallGraphSCCPass did not update the CallGraph correctly!"); - - // If the call site didn't exist in the CGN yet, add it. - CallGraphNode *CalleeNode; - if (Function *Callee = CS.getCalledFunction()) { - CalleeNode = CG.getOrInsertFunction(Callee); - ++NumDirectAdded; - } else { - CalleeNode = CG.getCallsExternalNode(); - ++NumIndirectAdded; - } - - CGN->addCalledFunction(CS, CalleeNode); - MadeChange = true; - } - - // We scanned the old callgraph node, removing invalidated call sites and - // then added back newly found call sites. One thing that can happen is - // that an old indirect call site was deleted and replaced with a new direct - // call. In this case, we have devirtualized a call, and CGSCCPM would like - // to iteratively optimize the new code. Unfortunately, we don't really - // have a great way to detect when this happens. As an approximation, we - // just look at whether the number of indirect calls is reduced and the - // number of direct calls is increased. There are tons of ways to fool this - // (e.g. DCE'ing an indirect call and duplicating an unrelated block with a - // direct call) but this is close enough. - if (NumIndirectRemoved > NumIndirectAdded && - NumDirectRemoved < NumDirectAdded) - DevirtualizedCall = true; - - // After scanning this function, if we still have entries in callsites, then - // they are dangling pointers. WeakVH should save us for this, so abort if - // this happens. - assert(CallSites.empty() && "Dangling pointers found in call sites map"); - - // Periodically do an explicit clear to remove tombstones when processing - // large scc's. - if ((FunctionNo & 15) == 15) - CallSites.clear(); - } - - DEBUG(if (MadeChange) { - dbgs() << "CGSCCPASSMGR: Refreshed SCC is now:\n"; - for (CallGraphNode *CGN : CurSCC) - CGN->dump(); - if (DevirtualizedCall) - dbgs() << "CGSCCPASSMGR: Refresh devirtualized a call!\n"; - - } else { - dbgs() << "CGSCCPASSMGR: SCC Refresh didn't change call graph.\n"; - } - ); - (void)MadeChange; - - return DevirtualizedCall; -} - -/// Execute the body of the entire pass manager on the specified SCC. -/// This keeps track of whether a function pass devirtualizes -/// any calls and returns it in DevirtualizedCall. -bool CGPassManager::RunAllPassesOnSCC(CallGraphSCC &CurSCC, CallGraph &CG, - bool &DevirtualizedCall) { - bool Changed = false; - - // Keep track of whether the callgraph is known to be up-to-date or not. - // The CGSSC pass manager runs two types of passes: - // CallGraphSCC Passes and other random function passes. Because other - // random function passes are not CallGraph aware, they may clobber the - // call graph by introducing new calls or deleting other ones. This flag - // is set to false when we run a function pass so that we know to clean up - // the callgraph when we need to run a CGSCCPass again. - bool CallGraphUpToDate = true; - - // Run all passes on current SCC. - for (unsigned PassNo = 0, e = getNumContainedPasses(); - PassNo != e; ++PassNo) { - Pass *P = getContainedPass(PassNo); - - // If we're in -debug-pass=Executions mode, construct the SCC node list, - // otherwise avoid constructing this string as it is expensive. - if (isPassDebuggingExecutionsOrMore()) { - std::string Functions; - #ifndef NDEBUG - raw_string_ostream OS(Functions); - for (CallGraphSCC::iterator I = CurSCC.begin(), E = CurSCC.end(); - I != E; ++I) { - if (I != CurSCC.begin()) OS << ", "; - (*I)->print(OS); - } - OS.flush(); - #endif - dumpPassInfo(P, EXECUTION_MSG, ON_CG_MSG, Functions); - } - dumpRequiredSet(P); - - initializeAnalysisImpl(P); - - // Actually run this pass on the current SCC. - Changed |= RunPassOnSCC(P, CurSCC, CG, - CallGraphUpToDate, DevirtualizedCall); - - if (Changed) - dumpPassInfo(P, MODIFICATION_MSG, ON_CG_MSG, ""); - dumpPreservedSet(P); - - verifyPreservedAnalysis(P); - removeNotPreservedAnalysis(P); - recordAvailableAnalysis(P); - removeDeadPasses(P, "", ON_CG_MSG); - } - - // If the callgraph was left out of date (because the last pass run was a - // functionpass), refresh it before we move on to the next SCC. - if (!CallGraphUpToDate) - DevirtualizedCall |= RefreshCallGraph(CurSCC, CG, false); - return Changed; -} - -/// Execute all of the passes scheduled for execution. Keep track of -/// whether any of the passes modifies the module, and if so, return true. -bool CGPassManager::runOnModule(Module &M) { - CallGraph &CG = getAnalysis<CallGraphWrapperPass>().getCallGraph(); - bool Changed = doInitialization(CG); - - // Walk the callgraph in bottom-up SCC order. - scc_iterator<CallGraph*> CGI = scc_begin(&CG); - - CallGraphSCC CurSCC(&CGI); - while (!CGI.isAtEnd()) { - // Copy the current SCC and increment past it so that the pass can hack - // on the SCC if it wants to without invalidating our iterator. - const std::vector<CallGraphNode *> &NodeVec = *CGI; - CurSCC.initialize(NodeVec.data(), NodeVec.data() + NodeVec.size()); - ++CGI; - - // At the top level, we run all the passes in this pass manager on the - // functions in this SCC. However, we support iterative compilation in the - // case where a function pass devirtualizes a call to a function. For - // example, it is very common for a function pass (often GVN or instcombine) - // to eliminate the addressing that feeds into a call. With that improved - // information, we would like the call to be an inline candidate, infer - // mod-ref information etc. - // - // Because of this, we allow iteration up to a specified iteration count. - // This only happens in the case of a devirtualized call, so we only burn - // compile time in the case that we're making progress. We also have a hard - // iteration count limit in case there is crazy code. - unsigned Iteration = 0; - bool DevirtualizedCall = false; - do { - DEBUG(if (Iteration) - dbgs() << " SCCPASSMGR: Re-visiting SCC, iteration #" - << Iteration << '\n'); - DevirtualizedCall = false; - Changed |= RunAllPassesOnSCC(CurSCC, CG, DevirtualizedCall); - } while (Iteration++ < MaxIterations && DevirtualizedCall); - - if (DevirtualizedCall) - DEBUG(dbgs() << " CGSCCPASSMGR: Stopped iteration after " << Iteration - << " times, due to -max-cg-scc-iterations\n"); - - if (Iteration > MaxSCCIterations) - MaxSCCIterations = Iteration; - - } - Changed |= doFinalization(CG); - return Changed; -} - - -/// Initialize CG -bool CGPassManager::doInitialization(CallGraph &CG) { - bool Changed = false; - for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) { - if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) { - assert(PM->getPassManagerType() == PMT_FunctionPassManager && - "Invalid CGPassManager member"); - Changed |= ((FPPassManager*)PM)->doInitialization(CG.getModule()); - } else { - Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doInitialization(CG); - } - } - return Changed; -} - -/// Finalize CG -bool CGPassManager::doFinalization(CallGraph &CG) { - bool Changed = false; - for (unsigned i = 0, e = getNumContainedPasses(); i != e; ++i) { - if (PMDataManager *PM = getContainedPass(i)->getAsPMDataManager()) { - assert(PM->getPassManagerType() == PMT_FunctionPassManager && - "Invalid CGPassManager member"); - Changed |= ((FPPassManager*)PM)->doFinalization(CG.getModule()); - } else { - Changed |= ((CallGraphSCCPass*)getContainedPass(i))->doFinalization(CG); - } - } - return Changed; -} - -//===----------------------------------------------------------------------===// -// CallGraphSCC Implementation -//===----------------------------------------------------------------------===// - -/// This informs the SCC and the pass manager that the specified -/// Old node has been deleted, and New is to be used in its place. -void CallGraphSCC::ReplaceNode(CallGraphNode *Old, CallGraphNode *New) { - assert(Old != New && "Should not replace node with self"); - for (unsigned i = 0; ; ++i) { - assert(i != Nodes.size() && "Node not in SCC"); - if (Nodes[i] != Old) continue; - Nodes[i] = New; - break; - } - - // Update the active scc_iterator so that it doesn't contain dangling - // pointers to the old CallGraphNode. - scc_iterator<CallGraph*> *CGI = (scc_iterator<CallGraph*>*)Context; - CGI->ReplaceNode(Old, New); -} - - -//===----------------------------------------------------------------------===// -// CallGraphSCCPass Implementation -//===----------------------------------------------------------------------===// - -/// Assign pass manager to manage this pass. -void CallGraphSCCPass::assignPassManager(PMStack &PMS, - PassManagerType PreferredType) { - // Find CGPassManager - while (!PMS.empty() && - PMS.top()->getPassManagerType() > PMT_CallGraphPassManager) - PMS.pop(); - - assert(!PMS.empty() && "Unable to handle Call Graph Pass"); - CGPassManager *CGP; - - if (PMS.top()->getPassManagerType() == PMT_CallGraphPassManager) - CGP = (CGPassManager*)PMS.top(); - else { - // Create new Call Graph SCC Pass Manager if it does not exist. - assert(!PMS.empty() && "Unable to create Call Graph Pass Manager"); - PMDataManager *PMD = PMS.top(); - - // [1] Create new Call Graph Pass Manager - CGP = new CGPassManager(); - - // [2] Set up new manager's top level manager - PMTopLevelManager *TPM = PMD->getTopLevelManager(); - TPM->addIndirectPassManager(CGP); - - // [3] Assign manager to manage this new manager. This may create - // and push new managers into PMS - Pass *P = CGP; - TPM->schedulePass(P); - - // [4] Push new manager into PMS - PMS.push(CGP); - } - - CGP->add(this); -} - -/// For this class, we declare that we require and preserve the call graph. -/// If the derived class implements this method, it should -/// always explicitly call the implementation here. -void CallGraphSCCPass::getAnalysisUsage(AnalysisUsage &AU) const { - AU.addRequired<CallGraphWrapperPass>(); - AU.addPreserved<CallGraphWrapperPass>(); -} - - -//===----------------------------------------------------------------------===// -// PrintCallGraphPass Implementation -//===----------------------------------------------------------------------===// - -namespace { - /// PrintCallGraphPass - Print a Module corresponding to a call graph. - /// - class PrintCallGraphPass : public CallGraphSCCPass { - std::string Banner; - raw_ostream &Out; // raw_ostream to print on. - - public: - static char ID; - PrintCallGraphPass(const std::string &B, raw_ostream &o) - : CallGraphSCCPass(ID), Banner(B), Out(o) {} - - void getAnalysisUsage(AnalysisUsage &AU) const override { - AU.setPreservesAll(); - } - - bool runOnSCC(CallGraphSCC &SCC) override { - Out << Banner; - for (CallGraphNode *CGN : SCC) { - if (CGN->getFunction()) - CGN->getFunction()->print(Out); - else - Out << "\nPrinting <null> Function\n"; - } - return false; - } - }; - -} // end anonymous namespace. - -char PrintCallGraphPass::ID = 0; - -Pass *CallGraphSCCPass::createPrinterPass(raw_ostream &O, - const std::string &Banner) const { - return new PrintCallGraphPass(Banner, O); -} - diff --git a/contrib/llvm/lib/Analysis/IPA/CallPrinter.cpp b/contrib/llvm/lib/Analysis/IPA/CallPrinter.cpp deleted file mode 100644 index 68dcd3c..0000000 --- a/contrib/llvm/lib/Analysis/IPA/CallPrinter.cpp +++ /dev/null @@ -1,92 +0,0 @@ -//===- CallPrinter.cpp - DOT printer for call graph -----------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines '-dot-callgraph', which emit a callgraph.<fnname>.dot -// containing the call graph of a module. -// -// There is also a pass available to directly call dotty ('-view-callgraph'). -// -//===----------------------------------------------------------------------===// - -#include "llvm/Analysis/CallGraph.h" -#include "llvm/Analysis/CallPrinter.h" -#include "llvm/Analysis/DOTGraphTraitsPass.h" - -using namespace llvm; - -namespace llvm { - -template <> struct DOTGraphTraits<CallGraph *> : public DefaultDOTGraphTraits { - DOTGraphTraits(bool isSimple = false) : DefaultDOTGraphTraits(isSimple) {} - - static std::string getGraphName(CallGraph *Graph) { return "Call graph"; } - - std::string getNodeLabel(CallGraphNode *Node, CallGraph *Graph) { - if (Function *Func = Node->getFunction()) - return Func->getName(); - - return "external node"; - } -}; - -struct AnalysisCallGraphWrapperPassTraits { - static CallGraph *getGraph(CallGraphWrapperPass *P) { - return &P->getCallGraph(); - } -}; - -} // end llvm namespace - -namespace { - -struct CallGraphViewer - : public DOTGraphTraitsModuleViewer<CallGraphWrapperPass, true, CallGraph *, - AnalysisCallGraphWrapperPassTraits> { - static char ID; - - CallGraphViewer() - : DOTGraphTraitsModuleViewer<CallGraphWrapperPass, true, CallGraph *, - AnalysisCallGraphWrapperPassTraits>( - "callgraph", ID) { - initializeCallGraphViewerPass(*PassRegistry::getPassRegistry()); - } -}; - -struct CallGraphPrinter : public DOTGraphTraitsModulePrinter< - CallGraphWrapperPass, true, CallGraph *, - AnalysisCallGraphWrapperPassTraits> { - static char ID; - - CallGraphPrinter() - : DOTGraphTraitsModulePrinter<CallGraphWrapperPass, true, CallGraph *, - AnalysisCallGraphWrapperPassTraits>( - "callgraph", ID) { - initializeCallGraphPrinterPass(*PassRegistry::getPassRegistry()); - } -}; - -} // end anonymous namespace - -char CallGraphViewer::ID = 0; -INITIALIZE_PASS(CallGraphViewer, "view-callgraph", "View call graph", false, - false) - -char CallGraphPrinter::ID = 0; -INITIALIZE_PASS(CallGraphPrinter, "dot-callgraph", - "Print call graph to 'dot' file", false, false) - -// Create methods available outside of this file, to use them -// "include/llvm/LinkAllPasses.h". Otherwise the pass would be deleted by -// the link time optimization. - -ModulePass *llvm::createCallGraphViewerPass() { return new CallGraphViewer(); } - -ModulePass *llvm::createCallGraphPrinterPass() { - return new CallGraphPrinter(); -} diff --git a/contrib/llvm/lib/Analysis/IPA/GlobalsModRef.cpp b/contrib/llvm/lib/Analysis/IPA/GlobalsModRef.cpp deleted file mode 100644 index 28fb49c..0000000 --- a/contrib/llvm/lib/Analysis/IPA/GlobalsModRef.cpp +++ /dev/null @@ -1,609 +0,0 @@ -//===- GlobalsModRef.cpp - Simple Mod/Ref Analysis for Globals ------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This simple pass provides alias and mod/ref information for global values -// that do not have their address taken, and keeps track of whether functions -// read or write memory (are "pure"). For this simple (but very common) case, -// we can provide pretty accurate and useful information. -// -//===----------------------------------------------------------------------===// - -#include "llvm/Analysis/Passes.h" -#include "llvm/ADT/SCCIterator.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/Analysis/AliasAnalysis.h" -#include "llvm/Analysis/CallGraph.h" -#include "llvm/Analysis/MemoryBuiltins.h" -#include "llvm/Analysis/ValueTracking.h" -#include "llvm/IR/Constants.h" -#include "llvm/IR/DerivedTypes.h" -#include "llvm/IR/InstIterator.h" -#include "llvm/IR/Instructions.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/Module.h" -#include "llvm/Pass.h" -#include "llvm/Support/CommandLine.h" -#include <set> -using namespace llvm; - -#define DEBUG_TYPE "globalsmodref-aa" - -STATISTIC(NumNonAddrTakenGlobalVars, - "Number of global vars without address taken"); -STATISTIC(NumNonAddrTakenFunctions,"Number of functions without address taken"); -STATISTIC(NumNoMemFunctions, "Number of functions that do not access memory"); -STATISTIC(NumReadMemFunctions, "Number of functions that only read memory"); -STATISTIC(NumIndirectGlobalVars, "Number of indirect global objects"); - -namespace { -/// FunctionRecord - One instance of this structure is stored for every -/// function in the program. Later, the entries for these functions are -/// removed if the function is found to call an external function (in which -/// case we know nothing about it. -struct FunctionRecord { - /// GlobalInfo - Maintain mod/ref info for all of the globals without - /// addresses taken that are read or written (transitively) by this - /// function. - std::map<const GlobalValue *, unsigned> GlobalInfo; - - /// MayReadAnyGlobal - May read global variables, but it is not known which. - bool MayReadAnyGlobal; - - unsigned getInfoForGlobal(const GlobalValue *GV) const { - unsigned Effect = MayReadAnyGlobal ? AliasAnalysis::Ref : 0; - std::map<const GlobalValue *, unsigned>::const_iterator I = - GlobalInfo.find(GV); - if (I != GlobalInfo.end()) - Effect |= I->second; - return Effect; - } - - /// FunctionEffect - Capture whether or not this function reads or writes to - /// ANY memory. If not, we can do a lot of aggressive analysis on it. - unsigned FunctionEffect; - - FunctionRecord() : MayReadAnyGlobal(false), FunctionEffect(0) {} -}; - -/// GlobalsModRef - The actual analysis pass. -class GlobalsModRef : public ModulePass, public AliasAnalysis { - /// NonAddressTakenGlobals - The globals that do not have their addresses - /// taken. - std::set<const GlobalValue *> NonAddressTakenGlobals; - - /// IndirectGlobals - The memory pointed to by this global is known to be - /// 'owned' by the global. - std::set<const GlobalValue *> IndirectGlobals; - - /// AllocsForIndirectGlobals - If an instruction allocates memory for an - /// indirect global, this map indicates which one. - std::map<const Value *, const GlobalValue *> AllocsForIndirectGlobals; - - /// FunctionInfo - For each function, keep track of what globals are - /// modified or read. - std::map<const Function *, FunctionRecord> FunctionInfo; - -public: - static char ID; - GlobalsModRef() : ModulePass(ID) { - initializeGlobalsModRefPass(*PassRegistry::getPassRegistry()); - } - - bool runOnModule(Module &M) override { - InitializeAliasAnalysis(this, &M.getDataLayout()); - - // Find non-addr taken globals. - AnalyzeGlobals(M); - - // Propagate on CG. - AnalyzeCallGraph(getAnalysis<CallGraphWrapperPass>().getCallGraph(), M); - return false; - } - - void getAnalysisUsage(AnalysisUsage &AU) const override { - AliasAnalysis::getAnalysisUsage(AU); - AU.addRequired<CallGraphWrapperPass>(); - AU.setPreservesAll(); // Does not transform code - } - - //------------------------------------------------ - // Implement the AliasAnalysis API - // - AliasResult alias(const MemoryLocation &LocA, - const MemoryLocation &LocB) override; - ModRefResult getModRefInfo(ImmutableCallSite CS, - const MemoryLocation &Loc) override; - ModRefResult getModRefInfo(ImmutableCallSite CS1, - ImmutableCallSite CS2) override { - return AliasAnalysis::getModRefInfo(CS1, CS2); - } - - /// getModRefBehavior - Return the behavior of the specified function if - /// called from the specified call site. The call site may be null in which - /// case the most generic behavior of this function should be returned. - ModRefBehavior getModRefBehavior(const Function *F) override { - ModRefBehavior Min = UnknownModRefBehavior; - - if (FunctionRecord *FR = getFunctionInfo(F)) { - if (FR->FunctionEffect == 0) - Min = DoesNotAccessMemory; - else if ((FR->FunctionEffect & Mod) == 0) - Min = OnlyReadsMemory; - } - - return ModRefBehavior(AliasAnalysis::getModRefBehavior(F) & Min); - } - - /// getModRefBehavior - Return the behavior of the specified function if - /// called from the specified call site. The call site may be null in which - /// case the most generic behavior of this function should be returned. - ModRefBehavior getModRefBehavior(ImmutableCallSite CS) override { - ModRefBehavior Min = UnknownModRefBehavior; - - if (const Function *F = CS.getCalledFunction()) - if (FunctionRecord *FR = getFunctionInfo(F)) { - if (FR->FunctionEffect == 0) - Min = DoesNotAccessMemory; - else if ((FR->FunctionEffect & Mod) == 0) - Min = OnlyReadsMemory; - } - - return ModRefBehavior(AliasAnalysis::getModRefBehavior(CS) & Min); - } - - void deleteValue(Value *V) override; - void addEscapingUse(Use &U) override; - - /// getAdjustedAnalysisPointer - This method is used when a pass implements - /// an analysis interface through multiple inheritance. If needed, it - /// should override this to adjust the this pointer as needed for the - /// specified pass info. - void *getAdjustedAnalysisPointer(AnalysisID PI) override { - if (PI == &AliasAnalysis::ID) - return (AliasAnalysis *)this; - return this; - } - -private: - /// getFunctionInfo - Return the function info for the function, or null if - /// we don't have anything useful to say about it. - FunctionRecord *getFunctionInfo(const Function *F) { - std::map<const Function *, FunctionRecord>::iterator I = - FunctionInfo.find(F); - if (I != FunctionInfo.end()) - return &I->second; - return nullptr; - } - - void AnalyzeGlobals(Module &M); - void AnalyzeCallGraph(CallGraph &CG, Module &M); - bool AnalyzeUsesOfPointer(Value *V, std::vector<Function *> &Readers, - std::vector<Function *> &Writers, - GlobalValue *OkayStoreDest = nullptr); - bool AnalyzeIndirectGlobalMemory(GlobalValue *GV); -}; -} - -char GlobalsModRef::ID = 0; -INITIALIZE_AG_PASS_BEGIN(GlobalsModRef, AliasAnalysis, "globalsmodref-aa", - "Simple mod/ref analysis for globals", false, true, - false) -INITIALIZE_PASS_DEPENDENCY(CallGraphWrapperPass) -INITIALIZE_AG_PASS_END(GlobalsModRef, AliasAnalysis, "globalsmodref-aa", - "Simple mod/ref analysis for globals", false, true, - false) - -Pass *llvm::createGlobalsModRefPass() { return new GlobalsModRef(); } - -/// AnalyzeGlobals - Scan through the users of all of the internal -/// GlobalValue's in the program. If none of them have their "address taken" -/// (really, their address passed to something nontrivial), record this fact, -/// and record the functions that they are used directly in. -void GlobalsModRef::AnalyzeGlobals(Module &M) { - std::vector<Function *> Readers, Writers; - for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I) - if (I->hasLocalLinkage()) { - if (!AnalyzeUsesOfPointer(I, Readers, Writers)) { - // Remember that we are tracking this global. - NonAddressTakenGlobals.insert(I); - ++NumNonAddrTakenFunctions; - } - Readers.clear(); - Writers.clear(); - } - - for (Module::global_iterator I = M.global_begin(), E = M.global_end(); I != E; - ++I) - if (I->hasLocalLinkage()) { - if (!AnalyzeUsesOfPointer(I, Readers, Writers)) { - // Remember that we are tracking this global, and the mod/ref fns - NonAddressTakenGlobals.insert(I); - - for (unsigned i = 0, e = Readers.size(); i != e; ++i) - FunctionInfo[Readers[i]].GlobalInfo[I] |= Ref; - - if (!I->isConstant()) // No need to keep track of writers to constants - for (unsigned i = 0, e = Writers.size(); i != e; ++i) - FunctionInfo[Writers[i]].GlobalInfo[I] |= Mod; - ++NumNonAddrTakenGlobalVars; - - // If this global holds a pointer type, see if it is an indirect global. - if (I->getType()->getElementType()->isPointerTy() && - AnalyzeIndirectGlobalMemory(I)) - ++NumIndirectGlobalVars; - } - Readers.clear(); - Writers.clear(); - } -} - -/// AnalyzeUsesOfPointer - Look at all of the users of the specified pointer. -/// If this is used by anything complex (i.e., the address escapes), return -/// true. Also, while we are at it, keep track of those functions that read and -/// write to the value. -/// -/// If OkayStoreDest is non-null, stores into this global are allowed. -bool GlobalsModRef::AnalyzeUsesOfPointer(Value *V, - std::vector<Function *> &Readers, - std::vector<Function *> &Writers, - GlobalValue *OkayStoreDest) { - if (!V->getType()->isPointerTy()) - return true; - - for (Use &U : V->uses()) { - User *I = U.getUser(); - if (LoadInst *LI = dyn_cast<LoadInst>(I)) { - Readers.push_back(LI->getParent()->getParent()); - } else if (StoreInst *SI = dyn_cast<StoreInst>(I)) { - if (V == SI->getOperand(1)) { - Writers.push_back(SI->getParent()->getParent()); - } else if (SI->getOperand(1) != OkayStoreDest) { - return true; // Storing the pointer - } - } else if (Operator::getOpcode(I) == Instruction::GetElementPtr) { - if (AnalyzeUsesOfPointer(I, Readers, Writers)) - return true; - } else if (Operator::getOpcode(I) == Instruction::BitCast) { - if (AnalyzeUsesOfPointer(I, Readers, Writers, OkayStoreDest)) - return true; - } else if (auto CS = CallSite(I)) { - // Make sure that this is just the function being called, not that it is - // passing into the function. - if (!CS.isCallee(&U)) { - // Detect calls to free. - if (isFreeCall(I, TLI)) - Writers.push_back(CS->getParent()->getParent()); - else - return true; // Argument of an unknown call. - } - } else if (ICmpInst *ICI = dyn_cast<ICmpInst>(I)) { - if (!isa<ConstantPointerNull>(ICI->getOperand(1))) - return true; // Allow comparison against null. - } else { - return true; - } - } - - return false; -} - -/// AnalyzeIndirectGlobalMemory - We found an non-address-taken global variable -/// which holds a pointer type. See if the global always points to non-aliased -/// heap memory: that is, all initializers of the globals are allocations, and -/// those allocations have no use other than initialization of the global. -/// Further, all loads out of GV must directly use the memory, not store the -/// pointer somewhere. If this is true, we consider the memory pointed to by -/// GV to be owned by GV and can disambiguate other pointers from it. -bool GlobalsModRef::AnalyzeIndirectGlobalMemory(GlobalValue *GV) { - // Keep track of values related to the allocation of the memory, f.e. the - // value produced by the malloc call and any casts. - std::vector<Value *> AllocRelatedValues; - - // Walk the user list of the global. If we find anything other than a direct - // load or store, bail out. - for (User *U : GV->users()) { - if (LoadInst *LI = dyn_cast<LoadInst>(U)) { - // The pointer loaded from the global can only be used in simple ways: - // we allow addressing of it and loading storing to it. We do *not* allow - // storing the loaded pointer somewhere else or passing to a function. - std::vector<Function *> ReadersWriters; - if (AnalyzeUsesOfPointer(LI, ReadersWriters, ReadersWriters)) - return false; // Loaded pointer escapes. - // TODO: Could try some IP mod/ref of the loaded pointer. - } else if (StoreInst *SI = dyn_cast<StoreInst>(U)) { - // Storing the global itself. - if (SI->getOperand(0) == GV) - return false; - - // If storing the null pointer, ignore it. - if (isa<ConstantPointerNull>(SI->getOperand(0))) - continue; - - // Check the value being stored. - Value *Ptr = GetUnderlyingObject(SI->getOperand(0), - GV->getParent()->getDataLayout()); - - if (!isAllocLikeFn(Ptr, TLI)) - return false; // Too hard to analyze. - - // Analyze all uses of the allocation. If any of them are used in a - // non-simple way (e.g. stored to another global) bail out. - std::vector<Function *> ReadersWriters; - if (AnalyzeUsesOfPointer(Ptr, ReadersWriters, ReadersWriters, GV)) - return false; // Loaded pointer escapes. - - // Remember that this allocation is related to the indirect global. - AllocRelatedValues.push_back(Ptr); - } else { - // Something complex, bail out. - return false; - } - } - - // Okay, this is an indirect global. Remember all of the allocations for - // this global in AllocsForIndirectGlobals. - while (!AllocRelatedValues.empty()) { - AllocsForIndirectGlobals[AllocRelatedValues.back()] = GV; - AllocRelatedValues.pop_back(); - } - IndirectGlobals.insert(GV); - return true; -} - -/// AnalyzeCallGraph - At this point, we know the functions where globals are -/// immediately stored to and read from. Propagate this information up the call -/// graph to all callers and compute the mod/ref info for all memory for each -/// function. -void GlobalsModRef::AnalyzeCallGraph(CallGraph &CG, Module &M) { - // We do a bottom-up SCC traversal of the call graph. In other words, we - // visit all callees before callers (leaf-first). - for (scc_iterator<CallGraph *> I = scc_begin(&CG); !I.isAtEnd(); ++I) { - const std::vector<CallGraphNode *> &SCC = *I; - assert(!SCC.empty() && "SCC with no functions?"); - - if (!SCC[0]->getFunction()) { - // Calls externally - can't say anything useful. Remove any existing - // function records (may have been created when scanning globals). - for (unsigned i = 0, e = SCC.size(); i != e; ++i) - FunctionInfo.erase(SCC[i]->getFunction()); - continue; - } - - FunctionRecord &FR = FunctionInfo[SCC[0]->getFunction()]; - - bool KnowNothing = false; - unsigned FunctionEffect = 0; - - // Collect the mod/ref properties due to called functions. We only compute - // one mod-ref set. - for (unsigned i = 0, e = SCC.size(); i != e && !KnowNothing; ++i) { - Function *F = SCC[i]->getFunction(); - if (!F) { - KnowNothing = true; - break; - } - - if (F->isDeclaration()) { - // Try to get mod/ref behaviour from function attributes. - if (F->doesNotAccessMemory()) { - // Can't do better than that! - } else if (F->onlyReadsMemory()) { - FunctionEffect |= Ref; - if (!F->isIntrinsic()) - // This function might call back into the module and read a global - - // consider every global as possibly being read by this function. - FR.MayReadAnyGlobal = true; - } else { - FunctionEffect |= ModRef; - // Can't say anything useful unless it's an intrinsic - they don't - // read or write global variables of the kind considered here. - KnowNothing = !F->isIntrinsic(); - } - continue; - } - - for (CallGraphNode::iterator CI = SCC[i]->begin(), E = SCC[i]->end(); - CI != E && !KnowNothing; ++CI) - if (Function *Callee = CI->second->getFunction()) { - if (FunctionRecord *CalleeFR = getFunctionInfo(Callee)) { - // Propagate function effect up. - FunctionEffect |= CalleeFR->FunctionEffect; - - // Incorporate callee's effects on globals into our info. - for (const auto &G : CalleeFR->GlobalInfo) - FR.GlobalInfo[G.first] |= G.second; - FR.MayReadAnyGlobal |= CalleeFR->MayReadAnyGlobal; - } else { - // Can't say anything about it. However, if it is inside our SCC, - // then nothing needs to be done. - CallGraphNode *CalleeNode = CG[Callee]; - if (std::find(SCC.begin(), SCC.end(), CalleeNode) == SCC.end()) - KnowNothing = true; - } - } else { - KnowNothing = true; - } - } - - // If we can't say anything useful about this SCC, remove all SCC functions - // from the FunctionInfo map. - if (KnowNothing) { - for (unsigned i = 0, e = SCC.size(); i != e; ++i) - FunctionInfo.erase(SCC[i]->getFunction()); - continue; - } - - // Scan the function bodies for explicit loads or stores. - for (auto *Node : SCC) { - if (FunctionEffect == ModRef) - break; // The mod/ref lattice saturates here. - for (Instruction &I : inst_range(Node->getFunction())) { - if (FunctionEffect == ModRef) - break; // The mod/ref lattice saturates here. - - // We handle calls specially because the graph-relevant aspects are - // handled above. - if (auto CS = CallSite(&I)) { - if (isAllocationFn(&I, TLI) || isFreeCall(&I, TLI)) { - // FIXME: It is completely unclear why this is necessary and not - // handled by the above graph code. - FunctionEffect |= ModRef; - } else if (Function *Callee = CS.getCalledFunction()) { - // The callgraph doesn't include intrinsic calls. - if (Callee->isIntrinsic()) { - ModRefBehavior Behaviour = - AliasAnalysis::getModRefBehavior(Callee); - FunctionEffect |= (Behaviour & ModRef); - } - } - continue; - } - - // All non-call instructions we use the primary predicates for whether - // thay read or write memory. - if (I.mayReadFromMemory()) - FunctionEffect |= Ref; - if (I.mayWriteToMemory()) - FunctionEffect |= Mod; - } - } - - if ((FunctionEffect & Mod) == 0) - ++NumReadMemFunctions; - if (FunctionEffect == 0) - ++NumNoMemFunctions; - FR.FunctionEffect = FunctionEffect; - - // Finally, now that we know the full effect on this SCC, clone the - // information to each function in the SCC. - for (unsigned i = 1, e = SCC.size(); i != e; ++i) - FunctionInfo[SCC[i]->getFunction()] = FR; - } -} - -/// alias - If one of the pointers is to a global that we are tracking, and the -/// other is some random pointer, we know there cannot be an alias, because the -/// address of the global isn't taken. -AliasResult GlobalsModRef::alias(const MemoryLocation &LocA, - const MemoryLocation &LocB) { - // Get the base object these pointers point to. - const Value *UV1 = GetUnderlyingObject(LocA.Ptr, *DL); - const Value *UV2 = GetUnderlyingObject(LocB.Ptr, *DL); - - // If either of the underlying values is a global, they may be non-addr-taken - // globals, which we can answer queries about. - const GlobalValue *GV1 = dyn_cast<GlobalValue>(UV1); - const GlobalValue *GV2 = dyn_cast<GlobalValue>(UV2); - if (GV1 || GV2) { - // If the global's address is taken, pretend we don't know it's a pointer to - // the global. - if (GV1 && !NonAddressTakenGlobals.count(GV1)) - GV1 = nullptr; - if (GV2 && !NonAddressTakenGlobals.count(GV2)) - GV2 = nullptr; - - // If the two pointers are derived from two different non-addr-taken - // globals, or if one is and the other isn't, we know these can't alias. - if ((GV1 || GV2) && GV1 != GV2) - return NoAlias; - - // Otherwise if they are both derived from the same addr-taken global, we - // can't know the two accesses don't overlap. - } - - // These pointers may be based on the memory owned by an indirect global. If - // so, we may be able to handle this. First check to see if the base pointer - // is a direct load from an indirect global. - GV1 = GV2 = nullptr; - if (const LoadInst *LI = dyn_cast<LoadInst>(UV1)) - if (GlobalVariable *GV = dyn_cast<GlobalVariable>(LI->getOperand(0))) - if (IndirectGlobals.count(GV)) - GV1 = GV; - if (const LoadInst *LI = dyn_cast<LoadInst>(UV2)) - if (const GlobalVariable *GV = dyn_cast<GlobalVariable>(LI->getOperand(0))) - if (IndirectGlobals.count(GV)) - GV2 = GV; - - // These pointers may also be from an allocation for the indirect global. If - // so, also handle them. - if (AllocsForIndirectGlobals.count(UV1)) - GV1 = AllocsForIndirectGlobals[UV1]; - if (AllocsForIndirectGlobals.count(UV2)) - GV2 = AllocsForIndirectGlobals[UV2]; - - // Now that we know whether the two pointers are related to indirect globals, - // use this to disambiguate the pointers. If either pointer is based on an - // indirect global and if they are not both based on the same indirect global, - // they cannot alias. - if ((GV1 || GV2) && GV1 != GV2) - return NoAlias; - - return AliasAnalysis::alias(LocA, LocB); -} - -AliasAnalysis::ModRefResult -GlobalsModRef::getModRefInfo(ImmutableCallSite CS, const MemoryLocation &Loc) { - unsigned Known = ModRef; - - // If we are asking for mod/ref info of a direct call with a pointer to a - // global we are tracking, return information if we have it. - const DataLayout &DL = CS.getCaller()->getParent()->getDataLayout(); - if (const GlobalValue *GV = - dyn_cast<GlobalValue>(GetUnderlyingObject(Loc.Ptr, DL))) - if (GV->hasLocalLinkage()) - if (const Function *F = CS.getCalledFunction()) - if (NonAddressTakenGlobals.count(GV)) - if (const FunctionRecord *FR = getFunctionInfo(F)) - Known = FR->getInfoForGlobal(GV); - - if (Known == NoModRef) - return NoModRef; // No need to query other mod/ref analyses - return ModRefResult(Known & AliasAnalysis::getModRefInfo(CS, Loc)); -} - -//===----------------------------------------------------------------------===// -// Methods to update the analysis as a result of the client transformation. -// -void GlobalsModRef::deleteValue(Value *V) { - if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) { - if (NonAddressTakenGlobals.erase(GV)) { - // This global might be an indirect global. If so, remove it and remove - // any AllocRelatedValues for it. - if (IndirectGlobals.erase(GV)) { - // Remove any entries in AllocsForIndirectGlobals for this global. - for (std::map<const Value *, const GlobalValue *>::iterator - I = AllocsForIndirectGlobals.begin(), - E = AllocsForIndirectGlobals.end(); - I != E;) { - if (I->second == GV) { - AllocsForIndirectGlobals.erase(I++); - } else { - ++I; - } - } - } - } - } - - // Otherwise, if this is an allocation related to an indirect global, remove - // it. - AllocsForIndirectGlobals.erase(V); - - AliasAnalysis::deleteValue(V); -} - -void GlobalsModRef::addEscapingUse(Use &U) { - // For the purposes of this analysis, it is conservatively correct to treat - // a newly escaping value equivalently to a deleted one. We could perhaps - // be more precise by processing the new use and attempting to update our - // saved analysis results to accommodate it. - deleteValue(U); - - AliasAnalysis::addEscapingUse(U); -} diff --git a/contrib/llvm/lib/Analysis/IPA/IPA.cpp b/contrib/llvm/lib/Analysis/IPA/IPA.cpp deleted file mode 100644 index 806bfb8..0000000 --- a/contrib/llvm/lib/Analysis/IPA/IPA.cpp +++ /dev/null @@ -1,30 +0,0 @@ -//===-- IPA.cpp -----------------------------------------------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements the common initialization routines for the IPA library. -// -//===----------------------------------------------------------------------===// - -#include "llvm/InitializePasses.h" -#include "llvm-c/Initialization.h" -#include "llvm/PassRegistry.h" - -using namespace llvm; - -/// initializeIPA - Initialize all passes linked into the IPA library. -void llvm::initializeIPA(PassRegistry &Registry) { - initializeCallGraphWrapperPassPass(Registry); - initializeCallGraphPrinterPass(Registry); - initializeCallGraphViewerPass(Registry); - initializeGlobalsModRefPass(Registry); -} - -void LLVMInitializeIPA(LLVMPassRegistryRef R) { - initializeIPA(*unwrap(R)); -} diff --git a/contrib/llvm/lib/Analysis/IPA/InlineCost.cpp b/contrib/llvm/lib/Analysis/IPA/InlineCost.cpp deleted file mode 100644 index c0d2e37..0000000 --- a/contrib/llvm/lib/Analysis/IPA/InlineCost.cpp +++ /dev/null @@ -1,1437 +0,0 @@ -//===- InlineCost.cpp - Cost analysis for inliner -------------------------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file implements inline cost analysis. -// -//===----------------------------------------------------------------------===// - -#include "llvm/Analysis/InlineCost.h" -#include "llvm/ADT/STLExtras.h" -#include "llvm/ADT/SetVector.h" -#include "llvm/ADT/SmallPtrSet.h" -#include "llvm/ADT/SmallVector.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/Analysis/AssumptionCache.h" -#include "llvm/Analysis/CodeMetrics.h" -#include "llvm/Analysis/ConstantFolding.h" -#include "llvm/Analysis/InstructionSimplify.h" -#include "llvm/Analysis/TargetTransformInfo.h" -#include "llvm/IR/CallSite.h" -#include "llvm/IR/CallingConv.h" -#include "llvm/IR/DataLayout.h" -#include "llvm/IR/GetElementPtrTypeIterator.h" -#include "llvm/IR/GlobalAlias.h" -#include "llvm/IR/InstVisitor.h" -#include "llvm/IR/IntrinsicInst.h" -#include "llvm/IR/Operator.h" -#include "llvm/Support/Debug.h" -#include "llvm/Support/raw_ostream.h" - -using namespace llvm; - -#define DEBUG_TYPE "inline-cost" - -STATISTIC(NumCallsAnalyzed, "Number of call sites analyzed"); - -namespace { - -class CallAnalyzer : public InstVisitor<CallAnalyzer, bool> { - typedef InstVisitor<CallAnalyzer, bool> Base; - friend class InstVisitor<CallAnalyzer, bool>; - - /// The TargetTransformInfo available for this compilation. - const TargetTransformInfo &TTI; - - /// The cache of @llvm.assume intrinsics. - AssumptionCacheTracker *ACT; - - // The called function. - Function &F; - - // The candidate callsite being analyzed. Please do not use this to do - // analysis in the caller function; we want the inline cost query to be - // easily cacheable. Instead, use the cover function paramHasAttr. - CallSite CandidateCS; - - int Threshold; - int Cost; - - bool IsCallerRecursive; - bool IsRecursiveCall; - bool ExposesReturnsTwice; - bool HasDynamicAlloca; - bool ContainsNoDuplicateCall; - bool HasReturn; - bool HasIndirectBr; - bool HasFrameEscape; - - /// Number of bytes allocated statically by the callee. - uint64_t AllocatedSize; - unsigned NumInstructions, NumVectorInstructions; - int FiftyPercentVectorBonus, TenPercentVectorBonus; - int VectorBonus; - - // While we walk the potentially-inlined instructions, we build up and - // maintain a mapping of simplified values specific to this callsite. The - // idea is to propagate any special information we have about arguments to - // this call through the inlinable section of the function, and account for - // likely simplifications post-inlining. The most important aspect we track - // is CFG altering simplifications -- when we prove a basic block dead, that - // can cause dramatic shifts in the cost of inlining a function. - DenseMap<Value *, Constant *> SimplifiedValues; - - // Keep track of the values which map back (through function arguments) to - // allocas on the caller stack which could be simplified through SROA. - DenseMap<Value *, Value *> SROAArgValues; - - // The mapping of caller Alloca values to their accumulated cost savings. If - // we have to disable SROA for one of the allocas, this tells us how much - // cost must be added. - DenseMap<Value *, int> SROAArgCosts; - - // Keep track of values which map to a pointer base and constant offset. - DenseMap<Value *, std::pair<Value *, APInt> > ConstantOffsetPtrs; - - // Custom simplification helper routines. - bool isAllocaDerivedArg(Value *V); - bool lookupSROAArgAndCost(Value *V, Value *&Arg, - DenseMap<Value *, int>::iterator &CostIt); - void disableSROA(DenseMap<Value *, int>::iterator CostIt); - void disableSROA(Value *V); - void accumulateSROACost(DenseMap<Value *, int>::iterator CostIt, - int InstructionCost); - bool isGEPOffsetConstant(GetElementPtrInst &GEP); - bool accumulateGEPOffset(GEPOperator &GEP, APInt &Offset); - bool simplifyCallSite(Function *F, CallSite CS); - ConstantInt *stripAndComputeInBoundsConstantOffsets(Value *&V); - - /// Return true if the given argument to the function being considered for - /// inlining has the given attribute set either at the call site or the - /// function declaration. Primarily used to inspect call site specific - /// attributes since these can be more precise than the ones on the callee - /// itself. - bool paramHasAttr(Argument *A, Attribute::AttrKind Attr); - - /// Return true if the given value is known non null within the callee if - /// inlined through this particular callsite. - bool isKnownNonNullInCallee(Value *V); - - // Custom analysis routines. - bool analyzeBlock(BasicBlock *BB, SmallPtrSetImpl<const Value *> &EphValues); - - // Disable several entry points to the visitor so we don't accidentally use - // them by declaring but not defining them here. - void visit(Module *); void visit(Module &); - void visit(Function *); void visit(Function &); - void visit(BasicBlock *); void visit(BasicBlock &); - - // Provide base case for our instruction visit. - bool visitInstruction(Instruction &I); - - // Our visit overrides. - bool visitAlloca(AllocaInst &I); - bool visitPHI(PHINode &I); - bool visitGetElementPtr(GetElementPtrInst &I); - bool visitBitCast(BitCastInst &I); - bool visitPtrToInt(PtrToIntInst &I); - bool visitIntToPtr(IntToPtrInst &I); - bool visitCastInst(CastInst &I); - bool visitUnaryInstruction(UnaryInstruction &I); - bool visitCmpInst(CmpInst &I); - bool visitSub(BinaryOperator &I); - bool visitBinaryOperator(BinaryOperator &I); - bool visitLoad(LoadInst &I); - bool visitStore(StoreInst &I); - bool visitExtractValue(ExtractValueInst &I); - bool visitInsertValue(InsertValueInst &I); - bool visitCallSite(CallSite CS); - bool visitReturnInst(ReturnInst &RI); - bool visitBranchInst(BranchInst &BI); - bool visitSwitchInst(SwitchInst &SI); - bool visitIndirectBrInst(IndirectBrInst &IBI); - bool visitResumeInst(ResumeInst &RI); - bool visitUnreachableInst(UnreachableInst &I); - -public: - CallAnalyzer(const TargetTransformInfo &TTI, AssumptionCacheTracker *ACT, - Function &Callee, int Threshold, CallSite CSArg) - : TTI(TTI), ACT(ACT), F(Callee), CandidateCS(CSArg), Threshold(Threshold), - Cost(0), IsCallerRecursive(false), IsRecursiveCall(false), - ExposesReturnsTwice(false), HasDynamicAlloca(false), - ContainsNoDuplicateCall(false), HasReturn(false), HasIndirectBr(false), - HasFrameEscape(false), AllocatedSize(0), NumInstructions(0), - NumVectorInstructions(0), FiftyPercentVectorBonus(0), - TenPercentVectorBonus(0), VectorBonus(0), NumConstantArgs(0), - NumConstantOffsetPtrArgs(0), NumAllocaArgs(0), NumConstantPtrCmps(0), - NumConstantPtrDiffs(0), NumInstructionsSimplified(0), - SROACostSavings(0), SROACostSavingsLost(0) {} - - bool analyzeCall(CallSite CS); - - int getThreshold() { return Threshold; } - int getCost() { return Cost; } - - // Keep a bunch of stats about the cost savings found so we can print them - // out when debugging. - unsigned NumConstantArgs; - unsigned NumConstantOffsetPtrArgs; - unsigned NumAllocaArgs; - unsigned NumConstantPtrCmps; - unsigned NumConstantPtrDiffs; - unsigned NumInstructionsSimplified; - unsigned SROACostSavings; - unsigned SROACostSavingsLost; - - void dump(); -}; - -} // namespace - -/// \brief Test whether the given value is an Alloca-derived function argument. -bool CallAnalyzer::isAllocaDerivedArg(Value *V) { - return SROAArgValues.count(V); -} - -/// \brief Lookup the SROA-candidate argument and cost iterator which V maps to. -/// Returns false if V does not map to a SROA-candidate. -bool CallAnalyzer::lookupSROAArgAndCost( - Value *V, Value *&Arg, DenseMap<Value *, int>::iterator &CostIt) { - if (SROAArgValues.empty() || SROAArgCosts.empty()) - return false; - - DenseMap<Value *, Value *>::iterator ArgIt = SROAArgValues.find(V); - if (ArgIt == SROAArgValues.end()) - return false; - - Arg = ArgIt->second; - CostIt = SROAArgCosts.find(Arg); - return CostIt != SROAArgCosts.end(); -} - -/// \brief Disable SROA for the candidate marked by this cost iterator. -/// -/// This marks the candidate as no longer viable for SROA, and adds the cost -/// savings associated with it back into the inline cost measurement. -void CallAnalyzer::disableSROA(DenseMap<Value *, int>::iterator CostIt) { - // If we're no longer able to perform SROA we need to undo its cost savings - // and prevent subsequent analysis. - Cost += CostIt->second; - SROACostSavings -= CostIt->second; - SROACostSavingsLost += CostIt->second; - SROAArgCosts.erase(CostIt); -} - -/// \brief If 'V' maps to a SROA candidate, disable SROA for it. -void CallAnalyzer::disableSROA(Value *V) { - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(V, SROAArg, CostIt)) - disableSROA(CostIt); -} - -/// \brief Accumulate the given cost for a particular SROA candidate. -void CallAnalyzer::accumulateSROACost(DenseMap<Value *, int>::iterator CostIt, - int InstructionCost) { - CostIt->second += InstructionCost; - SROACostSavings += InstructionCost; -} - -/// \brief Check whether a GEP's indices are all constant. -/// -/// Respects any simplified values known during the analysis of this callsite. -bool CallAnalyzer::isGEPOffsetConstant(GetElementPtrInst &GEP) { - for (User::op_iterator I = GEP.idx_begin(), E = GEP.idx_end(); I != E; ++I) - if (!isa<Constant>(*I) && !SimplifiedValues.lookup(*I)) - return false; - - return true; -} - -/// \brief Accumulate a constant GEP offset into an APInt if possible. -/// -/// Returns false if unable to compute the offset for any reason. Respects any -/// simplified values known during the analysis of this callsite. -bool CallAnalyzer::accumulateGEPOffset(GEPOperator &GEP, APInt &Offset) { - const DataLayout &DL = F.getParent()->getDataLayout(); - unsigned IntPtrWidth = DL.getPointerSizeInBits(); - assert(IntPtrWidth == Offset.getBitWidth()); - - for (gep_type_iterator GTI = gep_type_begin(GEP), GTE = gep_type_end(GEP); - GTI != GTE; ++GTI) { - ConstantInt *OpC = dyn_cast<ConstantInt>(GTI.getOperand()); - if (!OpC) - if (Constant *SimpleOp = SimplifiedValues.lookup(GTI.getOperand())) - OpC = dyn_cast<ConstantInt>(SimpleOp); - if (!OpC) - return false; - if (OpC->isZero()) continue; - - // Handle a struct index, which adds its field offset to the pointer. - if (StructType *STy = dyn_cast<StructType>(*GTI)) { - unsigned ElementIdx = OpC->getZExtValue(); - const StructLayout *SL = DL.getStructLayout(STy); - Offset += APInt(IntPtrWidth, SL->getElementOffset(ElementIdx)); - continue; - } - - APInt TypeSize(IntPtrWidth, DL.getTypeAllocSize(GTI.getIndexedType())); - Offset += OpC->getValue().sextOrTrunc(IntPtrWidth) * TypeSize; - } - return true; -} - -bool CallAnalyzer::visitAlloca(AllocaInst &I) { - // Check whether inlining will turn a dynamic alloca into a static - // alloca, and handle that case. - if (I.isArrayAllocation()) { - if (Constant *Size = SimplifiedValues.lookup(I.getArraySize())) { - ConstantInt *AllocSize = dyn_cast<ConstantInt>(Size); - assert(AllocSize && "Allocation size not a constant int?"); - Type *Ty = I.getAllocatedType(); - AllocatedSize += Ty->getPrimitiveSizeInBits() * AllocSize->getZExtValue(); - return Base::visitAlloca(I); - } - } - - // Accumulate the allocated size. - if (I.isStaticAlloca()) { - const DataLayout &DL = F.getParent()->getDataLayout(); - Type *Ty = I.getAllocatedType(); - AllocatedSize += DL.getTypeAllocSize(Ty); - } - - // We will happily inline static alloca instructions. - if (I.isStaticAlloca()) - return Base::visitAlloca(I); - - // FIXME: This is overly conservative. Dynamic allocas are inefficient for - // a variety of reasons, and so we would like to not inline them into - // functions which don't currently have a dynamic alloca. This simply - // disables inlining altogether in the presence of a dynamic alloca. - HasDynamicAlloca = true; - return false; -} - -bool CallAnalyzer::visitPHI(PHINode &I) { - // FIXME: We should potentially be tracking values through phi nodes, - // especially when they collapse to a single value due to deleted CFG edges - // during inlining. - - // FIXME: We need to propagate SROA *disabling* through phi nodes, even - // though we don't want to propagate it's bonuses. The idea is to disable - // SROA if it *might* be used in an inappropriate manner. - - // Phi nodes are always zero-cost. - return true; -} - -bool CallAnalyzer::visitGetElementPtr(GetElementPtrInst &I) { - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - bool SROACandidate = lookupSROAArgAndCost(I.getPointerOperand(), - SROAArg, CostIt); - - // Try to fold GEPs of constant-offset call site argument pointers. This - // requires target data and inbounds GEPs. - if (I.isInBounds()) { - // Check if we have a base + offset for the pointer. - Value *Ptr = I.getPointerOperand(); - std::pair<Value *, APInt> BaseAndOffset = ConstantOffsetPtrs.lookup(Ptr); - if (BaseAndOffset.first) { - // Check if the offset of this GEP is constant, and if so accumulate it - // into Offset. - if (!accumulateGEPOffset(cast<GEPOperator>(I), BaseAndOffset.second)) { - // Non-constant GEPs aren't folded, and disable SROA. - if (SROACandidate) - disableSROA(CostIt); - return false; - } - - // Add the result as a new mapping to Base + Offset. - ConstantOffsetPtrs[&I] = BaseAndOffset; - - // Also handle SROA candidates here, we already know that the GEP is - // all-constant indexed. - if (SROACandidate) - SROAArgValues[&I] = SROAArg; - - return true; - } - } - - if (isGEPOffsetConstant(I)) { - if (SROACandidate) - SROAArgValues[&I] = SROAArg; - - // Constant GEPs are modeled as free. - return true; - } - - // Variable GEPs will require math and will disable SROA. - if (SROACandidate) - disableSROA(CostIt); - return false; -} - -bool CallAnalyzer::visitBitCast(BitCastInst &I) { - // Propagate constants through bitcasts. - Constant *COp = dyn_cast<Constant>(I.getOperand(0)); - if (!COp) - COp = SimplifiedValues.lookup(I.getOperand(0)); - if (COp) - if (Constant *C = ConstantExpr::getBitCast(COp, I.getType())) { - SimplifiedValues[&I] = C; - return true; - } - - // Track base/offsets through casts - std::pair<Value *, APInt> BaseAndOffset - = ConstantOffsetPtrs.lookup(I.getOperand(0)); - // Casts don't change the offset, just wrap it up. - if (BaseAndOffset.first) - ConstantOffsetPtrs[&I] = BaseAndOffset; - - // Also look for SROA candidates here. - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(I.getOperand(0), SROAArg, CostIt)) - SROAArgValues[&I] = SROAArg; - - // Bitcasts are always zero cost. - return true; -} - -bool CallAnalyzer::visitPtrToInt(PtrToIntInst &I) { - // Propagate constants through ptrtoint. - Constant *COp = dyn_cast<Constant>(I.getOperand(0)); - if (!COp) - COp = SimplifiedValues.lookup(I.getOperand(0)); - if (COp) - if (Constant *C = ConstantExpr::getPtrToInt(COp, I.getType())) { - SimplifiedValues[&I] = C; - return true; - } - - // Track base/offset pairs when converted to a plain integer provided the - // integer is large enough to represent the pointer. - unsigned IntegerSize = I.getType()->getScalarSizeInBits(); - const DataLayout &DL = F.getParent()->getDataLayout(); - if (IntegerSize >= DL.getPointerSizeInBits()) { - std::pair<Value *, APInt> BaseAndOffset - = ConstantOffsetPtrs.lookup(I.getOperand(0)); - if (BaseAndOffset.first) - ConstantOffsetPtrs[&I] = BaseAndOffset; - } - - // This is really weird. Technically, ptrtoint will disable SROA. However, - // unless that ptrtoint is *used* somewhere in the live basic blocks after - // inlining, it will be nuked, and SROA should proceed. All of the uses which - // would block SROA would also block SROA if applied directly to a pointer, - // and so we can just add the integer in here. The only places where SROA is - // preserved either cannot fire on an integer, or won't in-and-of themselves - // disable SROA (ext) w/o some later use that we would see and disable. - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(I.getOperand(0), SROAArg, CostIt)) - SROAArgValues[&I] = SROAArg; - - return TargetTransformInfo::TCC_Free == TTI.getUserCost(&I); -} - -bool CallAnalyzer::visitIntToPtr(IntToPtrInst &I) { - // Propagate constants through ptrtoint. - Constant *COp = dyn_cast<Constant>(I.getOperand(0)); - if (!COp) - COp = SimplifiedValues.lookup(I.getOperand(0)); - if (COp) - if (Constant *C = ConstantExpr::getIntToPtr(COp, I.getType())) { - SimplifiedValues[&I] = C; - return true; - } - - // Track base/offset pairs when round-tripped through a pointer without - // modifications provided the integer is not too large. - Value *Op = I.getOperand(0); - unsigned IntegerSize = Op->getType()->getScalarSizeInBits(); - const DataLayout &DL = F.getParent()->getDataLayout(); - if (IntegerSize <= DL.getPointerSizeInBits()) { - std::pair<Value *, APInt> BaseAndOffset = ConstantOffsetPtrs.lookup(Op); - if (BaseAndOffset.first) - ConstantOffsetPtrs[&I] = BaseAndOffset; - } - - // "Propagate" SROA here in the same manner as we do for ptrtoint above. - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(Op, SROAArg, CostIt)) - SROAArgValues[&I] = SROAArg; - - return TargetTransformInfo::TCC_Free == TTI.getUserCost(&I); -} - -bool CallAnalyzer::visitCastInst(CastInst &I) { - // Propagate constants through ptrtoint. - Constant *COp = dyn_cast<Constant>(I.getOperand(0)); - if (!COp) - COp = SimplifiedValues.lookup(I.getOperand(0)); - if (COp) - if (Constant *C = ConstantExpr::getCast(I.getOpcode(), COp, I.getType())) { - SimplifiedValues[&I] = C; - return true; - } - - // Disable SROA in the face of arbitrary casts we don't whitelist elsewhere. - disableSROA(I.getOperand(0)); - - return TargetTransformInfo::TCC_Free == TTI.getUserCost(&I); -} - -bool CallAnalyzer::visitUnaryInstruction(UnaryInstruction &I) { - Value *Operand = I.getOperand(0); - Constant *COp = dyn_cast<Constant>(Operand); - if (!COp) - COp = SimplifiedValues.lookup(Operand); - if (COp) { - const DataLayout &DL = F.getParent()->getDataLayout(); - if (Constant *C = ConstantFoldInstOperands(I.getOpcode(), I.getType(), - COp, DL)) { - SimplifiedValues[&I] = C; - return true; - } - } - - // Disable any SROA on the argument to arbitrary unary operators. - disableSROA(Operand); - - return false; -} - -bool CallAnalyzer::paramHasAttr(Argument *A, Attribute::AttrKind Attr) { - unsigned ArgNo = A->getArgNo(); - return CandidateCS.paramHasAttr(ArgNo+1, Attr); -} - -bool CallAnalyzer::isKnownNonNullInCallee(Value *V) { - // Does the *call site* have the NonNull attribute set on an argument? We - // use the attribute on the call site to memoize any analysis done in the - // caller. This will also trip if the callee function has a non-null - // parameter attribute, but that's a less interesting case because hopefully - // the callee would already have been simplified based on that. - if (Argument *A = dyn_cast<Argument>(V)) - if (paramHasAttr(A, Attribute::NonNull)) - return true; - - // Is this an alloca in the caller? This is distinct from the attribute case - // above because attributes aren't updated within the inliner itself and we - // always want to catch the alloca derived case. - if (isAllocaDerivedArg(V)) - // We can actually predict the result of comparisons between an - // alloca-derived value and null. Note that this fires regardless of - // SROA firing. - return true; - - return false; -} - -bool CallAnalyzer::visitCmpInst(CmpInst &I) { - Value *LHS = I.getOperand(0), *RHS = I.getOperand(1); - // First try to handle simplified comparisons. - if (!isa<Constant>(LHS)) - if (Constant *SimpleLHS = SimplifiedValues.lookup(LHS)) - LHS = SimpleLHS; - if (!isa<Constant>(RHS)) - if (Constant *SimpleRHS = SimplifiedValues.lookup(RHS)) - RHS = SimpleRHS; - if (Constant *CLHS = dyn_cast<Constant>(LHS)) { - if (Constant *CRHS = dyn_cast<Constant>(RHS)) - if (Constant *C = ConstantExpr::getCompare(I.getPredicate(), CLHS, CRHS)) { - SimplifiedValues[&I] = C; - return true; - } - } - - if (I.getOpcode() == Instruction::FCmp) - return false; - - // Otherwise look for a comparison between constant offset pointers with - // a common base. - Value *LHSBase, *RHSBase; - APInt LHSOffset, RHSOffset; - std::tie(LHSBase, LHSOffset) = ConstantOffsetPtrs.lookup(LHS); - if (LHSBase) { - std::tie(RHSBase, RHSOffset) = ConstantOffsetPtrs.lookup(RHS); - if (RHSBase && LHSBase == RHSBase) { - // We have common bases, fold the icmp to a constant based on the - // offsets. - Constant *CLHS = ConstantInt::get(LHS->getContext(), LHSOffset); - Constant *CRHS = ConstantInt::get(RHS->getContext(), RHSOffset); - if (Constant *C = ConstantExpr::getICmp(I.getPredicate(), CLHS, CRHS)) { - SimplifiedValues[&I] = C; - ++NumConstantPtrCmps; - return true; - } - } - } - - // If the comparison is an equality comparison with null, we can simplify it - // if we know the value (argument) can't be null - if (I.isEquality() && isa<ConstantPointerNull>(I.getOperand(1)) && - isKnownNonNullInCallee(I.getOperand(0))) { - bool IsNotEqual = I.getPredicate() == CmpInst::ICMP_NE; - SimplifiedValues[&I] = IsNotEqual ? ConstantInt::getTrue(I.getType()) - : ConstantInt::getFalse(I.getType()); - return true; - } - // Finally check for SROA candidates in comparisons. - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(I.getOperand(0), SROAArg, CostIt)) { - if (isa<ConstantPointerNull>(I.getOperand(1))) { - accumulateSROACost(CostIt, InlineConstants::InstrCost); - return true; - } - - disableSROA(CostIt); - } - - return false; -} - -bool CallAnalyzer::visitSub(BinaryOperator &I) { - // Try to handle a special case: we can fold computing the difference of two - // constant-related pointers. - Value *LHS = I.getOperand(0), *RHS = I.getOperand(1); - Value *LHSBase, *RHSBase; - APInt LHSOffset, RHSOffset; - std::tie(LHSBase, LHSOffset) = ConstantOffsetPtrs.lookup(LHS); - if (LHSBase) { - std::tie(RHSBase, RHSOffset) = ConstantOffsetPtrs.lookup(RHS); - if (RHSBase && LHSBase == RHSBase) { - // We have common bases, fold the subtract to a constant based on the - // offsets. - Constant *CLHS = ConstantInt::get(LHS->getContext(), LHSOffset); - Constant *CRHS = ConstantInt::get(RHS->getContext(), RHSOffset); - if (Constant *C = ConstantExpr::getSub(CLHS, CRHS)) { - SimplifiedValues[&I] = C; - ++NumConstantPtrDiffs; - return true; - } - } - } - - // Otherwise, fall back to the generic logic for simplifying and handling - // instructions. - return Base::visitSub(I); -} - -bool CallAnalyzer::visitBinaryOperator(BinaryOperator &I) { - Value *LHS = I.getOperand(0), *RHS = I.getOperand(1); - const DataLayout &DL = F.getParent()->getDataLayout(); - if (!isa<Constant>(LHS)) - if (Constant *SimpleLHS = SimplifiedValues.lookup(LHS)) - LHS = SimpleLHS; - if (!isa<Constant>(RHS)) - if (Constant *SimpleRHS = SimplifiedValues.lookup(RHS)) - RHS = SimpleRHS; - Value *SimpleV = nullptr; - if (auto FI = dyn_cast<FPMathOperator>(&I)) - SimpleV = - SimplifyFPBinOp(I.getOpcode(), LHS, RHS, FI->getFastMathFlags(), DL); - else - SimpleV = SimplifyBinOp(I.getOpcode(), LHS, RHS, DL); - - if (Constant *C = dyn_cast_or_null<Constant>(SimpleV)) { - SimplifiedValues[&I] = C; - return true; - } - - // Disable any SROA on arguments to arbitrary, unsimplified binary operators. - disableSROA(LHS); - disableSROA(RHS); - - return false; -} - -bool CallAnalyzer::visitLoad(LoadInst &I) { - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(I.getPointerOperand(), SROAArg, CostIt)) { - if (I.isSimple()) { - accumulateSROACost(CostIt, InlineConstants::InstrCost); - return true; - } - - disableSROA(CostIt); - } - - return false; -} - -bool CallAnalyzer::visitStore(StoreInst &I) { - Value *SROAArg; - DenseMap<Value *, int>::iterator CostIt; - if (lookupSROAArgAndCost(I.getPointerOperand(), SROAArg, CostIt)) { - if (I.isSimple()) { - accumulateSROACost(CostIt, InlineConstants::InstrCost); - return true; - } - - disableSROA(CostIt); - } - - return false; -} - -bool CallAnalyzer::visitExtractValue(ExtractValueInst &I) { - // Constant folding for extract value is trivial. - Constant *C = dyn_cast<Constant>(I.getAggregateOperand()); - if (!C) - C = SimplifiedValues.lookup(I.getAggregateOperand()); - if (C) { - SimplifiedValues[&I] = ConstantExpr::getExtractValue(C, I.getIndices()); - return true; - } - - // SROA can look through these but give them a cost. - return false; -} - -bool CallAnalyzer::visitInsertValue(InsertValueInst &I) { - // Constant folding for insert value is trivial. - Constant *AggC = dyn_cast<Constant>(I.getAggregateOperand()); - if (!AggC) - AggC = SimplifiedValues.lookup(I.getAggregateOperand()); - Constant *InsertedC = dyn_cast<Constant>(I.getInsertedValueOperand()); - if (!InsertedC) - InsertedC = SimplifiedValues.lookup(I.getInsertedValueOperand()); - if (AggC && InsertedC) { - SimplifiedValues[&I] = ConstantExpr::getInsertValue(AggC, InsertedC, - I.getIndices()); - return true; - } - - // SROA can look through these but give them a cost. - return false; -} - -/// \brief Try to simplify a call site. -/// -/// Takes a concrete function and callsite and tries to actually simplify it by -/// analyzing the arguments and call itself with instsimplify. Returns true if -/// it has simplified the callsite to some other entity (a constant), making it -/// free. -bool CallAnalyzer::simplifyCallSite(Function *F, CallSite CS) { - // FIXME: Using the instsimplify logic directly for this is inefficient - // because we have to continually rebuild the argument list even when no - // simplifications can be performed. Until that is fixed with remapping - // inside of instsimplify, directly constant fold calls here. - if (!canConstantFoldCallTo(F)) - return false; - - // Try to re-map the arguments to constants. - SmallVector<Constant *, 4> ConstantArgs; - ConstantArgs.reserve(CS.arg_size()); - for (CallSite::arg_iterator I = CS.arg_begin(), E = CS.arg_end(); - I != E; ++I) { - Constant *C = dyn_cast<Constant>(*I); - if (!C) - C = dyn_cast_or_null<Constant>(SimplifiedValues.lookup(*I)); - if (!C) - return false; // This argument doesn't map to a constant. - - ConstantArgs.push_back(C); - } - if (Constant *C = ConstantFoldCall(F, ConstantArgs)) { - SimplifiedValues[CS.getInstruction()] = C; - return true; - } - - return false; -} - -bool CallAnalyzer::visitCallSite(CallSite CS) { - if (CS.hasFnAttr(Attribute::ReturnsTwice) && - !F.hasFnAttribute(Attribute::ReturnsTwice)) { - // This aborts the entire analysis. - ExposesReturnsTwice = true; - return false; - } - if (CS.isCall() && - cast<CallInst>(CS.getInstruction())->cannotDuplicate()) - ContainsNoDuplicateCall = true; - - if (Function *F = CS.getCalledFunction()) { - // When we have a concrete function, first try to simplify it directly. - if (simplifyCallSite(F, CS)) - return true; - - // Next check if it is an intrinsic we know about. - // FIXME: Lift this into part of the InstVisitor. - if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(CS.getInstruction())) { - switch (II->getIntrinsicID()) { - default: - return Base::visitCallSite(CS); - - case Intrinsic::memset: - case Intrinsic::memcpy: - case Intrinsic::memmove: - // SROA can usually chew through these intrinsics, but they aren't free. - return false; - case Intrinsic::localescape: - HasFrameEscape = true; - return false; - } - } - - if (F == CS.getInstruction()->getParent()->getParent()) { - // This flag will fully abort the analysis, so don't bother with anything - // else. - IsRecursiveCall = true; - return false; - } - - if (TTI.isLoweredToCall(F)) { - // We account for the average 1 instruction per call argument setup - // here. - Cost += CS.arg_size() * InlineConstants::InstrCost; - - // Everything other than inline ASM will also have a significant cost - // merely from making the call. - if (!isa<InlineAsm>(CS.getCalledValue())) - Cost += InlineConstants::CallPenalty; - } - - return Base::visitCallSite(CS); - } - - // Otherwise we're in a very special case -- an indirect function call. See - // if we can be particularly clever about this. - Value *Callee = CS.getCalledValue(); - - // First, pay the price of the argument setup. We account for the average - // 1 instruction per call argument setup here. - Cost += CS.arg_size() * InlineConstants::InstrCost; - - // Next, check if this happens to be an indirect function call to a known - // function in this inline context. If not, we've done all we can. - Function *F = dyn_cast_or_null<Function>(SimplifiedValues.lookup(Callee)); - if (!F) - return Base::visitCallSite(CS); - - // If we have a constant that we are calling as a function, we can peer - // through it and see the function target. This happens not infrequently - // during devirtualization and so we want to give it a hefty bonus for - // inlining, but cap that bonus in the event that inlining wouldn't pan - // out. Pretend to inline the function, with a custom threshold. - CallAnalyzer CA(TTI, ACT, *F, InlineConstants::IndirectCallThreshold, CS); - if (CA.analyzeCall(CS)) { - // We were able to inline the indirect call! Subtract the cost from the - // bonus we want to apply, but don't go below zero. - Cost -= std::max(0, InlineConstants::IndirectCallThreshold - CA.getCost()); - } - - return Base::visitCallSite(CS); -} - -bool CallAnalyzer::visitReturnInst(ReturnInst &RI) { - // At least one return instruction will be free after inlining. - bool Free = !HasReturn; - HasReturn = true; - return Free; -} - -bool CallAnalyzer::visitBranchInst(BranchInst &BI) { - // We model unconditional branches as essentially free -- they really - // shouldn't exist at all, but handling them makes the behavior of the - // inliner more regular and predictable. Interestingly, conditional branches - // which will fold away are also free. - return BI.isUnconditional() || isa<ConstantInt>(BI.getCondition()) || - dyn_cast_or_null<ConstantInt>( - SimplifiedValues.lookup(BI.getCondition())); -} - -bool CallAnalyzer::visitSwitchInst(SwitchInst &SI) { - // We model unconditional switches as free, see the comments on handling - // branches. - if (isa<ConstantInt>(SI.getCondition())) - return true; - if (Value *V = SimplifiedValues.lookup(SI.getCondition())) - if (isa<ConstantInt>(V)) - return true; - - // Otherwise, we need to accumulate a cost proportional to the number of - // distinct successor blocks. This fan-out in the CFG cannot be represented - // for free even if we can represent the core switch as a jumptable that - // takes a single instruction. - // - // NB: We convert large switches which are just used to initialize large phi - // nodes to lookup tables instead in simplify-cfg, so this shouldn't prevent - // inlining those. It will prevent inlining in cases where the optimization - // does not (yet) fire. - SmallPtrSet<BasicBlock *, 8> SuccessorBlocks; - SuccessorBlocks.insert(SI.getDefaultDest()); - for (auto I = SI.case_begin(), E = SI.case_end(); I != E; ++I) - SuccessorBlocks.insert(I.getCaseSuccessor()); - // Add cost corresponding to the number of distinct destinations. The first - // we model as free because of fallthrough. - Cost += (SuccessorBlocks.size() - 1) * InlineConstants::InstrCost; - return false; -} - -bool CallAnalyzer::visitIndirectBrInst(IndirectBrInst &IBI) { - // We never want to inline functions that contain an indirectbr. This is - // incorrect because all the blockaddress's (in static global initializers - // for example) would be referring to the original function, and this - // indirect jump would jump from the inlined copy of the function into the - // original function which is extremely undefined behavior. - // FIXME: This logic isn't really right; we can safely inline functions with - // indirectbr's as long as no other function or global references the - // blockaddress of a block within the current function. - HasIndirectBr = true; - return false; -} - -bool CallAnalyzer::visitResumeInst(ResumeInst &RI) { - // FIXME: It's not clear that a single instruction is an accurate model for - // the inline cost of a resume instruction. - return false; -} - -bool CallAnalyzer::visitUnreachableInst(UnreachableInst &I) { - // FIXME: It might be reasonably to discount the cost of instructions leading - // to unreachable as they have the lowest possible impact on both runtime and - // code size. - return true; // No actual code is needed for unreachable. -} - -bool CallAnalyzer::visitInstruction(Instruction &I) { - // Some instructions are free. All of the free intrinsics can also be - // handled by SROA, etc. - if (TargetTransformInfo::TCC_Free == TTI.getUserCost(&I)) - return true; - - // We found something we don't understand or can't handle. Mark any SROA-able - // values in the operand list as no longer viable. - for (User::op_iterator OI = I.op_begin(), OE = I.op_end(); OI != OE; ++OI) - disableSROA(*OI); - - return false; -} - - -/// \brief Analyze a basic block for its contribution to the inline cost. -/// -/// This method walks the analyzer over every instruction in the given basic -/// block and accounts for their cost during inlining at this callsite. It -/// aborts early if the threshold has been exceeded or an impossible to inline -/// construct has been detected. It returns false if inlining is no longer -/// viable, and true if inlining remains viable. -bool CallAnalyzer::analyzeBlock(BasicBlock *BB, - SmallPtrSetImpl<const Value *> &EphValues) { - for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) { - // FIXME: Currently, the number of instructions in a function regardless of - // our ability to simplify them during inline to constants or dead code, - // are actually used by the vector bonus heuristic. As long as that's true, - // we have to special case debug intrinsics here to prevent differences in - // inlining due to debug symbols. Eventually, the number of unsimplified - // instructions shouldn't factor into the cost computation, but until then, - // hack around it here. - if (isa<DbgInfoIntrinsic>(I)) - continue; - - // Skip ephemeral values. - if (EphValues.count(I)) - continue; - - ++NumInstructions; - if (isa<ExtractElementInst>(I) || I->getType()->isVectorTy()) - ++NumVectorInstructions; - - // If the instruction is floating point, and the target says this operation is - // expensive or the function has the "use-soft-float" attribute, this may - // eventually become a library call. Treat the cost as such. - if (I->getType()->isFloatingPointTy()) { - bool hasSoftFloatAttr = false; - - // If the function has the "use-soft-float" attribute, mark it as expensive. - if (F.hasFnAttribute("use-soft-float")) { - Attribute Attr = F.getFnAttribute("use-soft-float"); - StringRef Val = Attr.getValueAsString(); - if (Val == "true") - hasSoftFloatAttr = true; - } - - if (TTI.getFPOpCost(I->getType()) == TargetTransformInfo::TCC_Expensive || - hasSoftFloatAttr) - Cost += InlineConstants::CallPenalty; - } - - // If the instruction simplified to a constant, there is no cost to this - // instruction. Visit the instructions using our InstVisitor to account for - // all of the per-instruction logic. The visit tree returns true if we - // consumed the instruction in any way, and false if the instruction's base - // cost should count against inlining. - if (Base::visit(I)) - ++NumInstructionsSimplified; - else - Cost += InlineConstants::InstrCost; - - // If the visit this instruction detected an uninlinable pattern, abort. - if (IsRecursiveCall || ExposesReturnsTwice || HasDynamicAlloca || - HasIndirectBr || HasFrameEscape) - return false; - - // If the caller is a recursive function then we don't want to inline - // functions which allocate a lot of stack space because it would increase - // the caller stack usage dramatically. - if (IsCallerRecursive && - AllocatedSize > InlineConstants::TotalAllocaSizeRecursiveCaller) - return false; - - // Check if we've past the maximum possible threshold so we don't spin in - // huge basic blocks that will never inline. - if (Cost > Threshold) - return false; - } - - return true; -} - -/// \brief Compute the base pointer and cumulative constant offsets for V. -/// -/// This strips all constant offsets off of V, leaving it the base pointer, and -/// accumulates the total constant offset applied in the returned constant. It -/// returns 0 if V is not a pointer, and returns the constant '0' if there are -/// no constant offsets applied. -ConstantInt *CallAnalyzer::stripAndComputeInBoundsConstantOffsets(Value *&V) { - if (!V->getType()->isPointerTy()) - return nullptr; - - const DataLayout &DL = F.getParent()->getDataLayout(); - unsigned IntPtrWidth = DL.getPointerSizeInBits(); - APInt Offset = APInt::getNullValue(IntPtrWidth); - - // Even though we don't look through PHI nodes, we could be called on an - // instruction in an unreachable block, which may be on a cycle. - SmallPtrSet<Value *, 4> Visited; - Visited.insert(V); - do { - if (GEPOperator *GEP = dyn_cast<GEPOperator>(V)) { - if (!GEP->isInBounds() || !accumulateGEPOffset(*GEP, Offset)) - return nullptr; - V = GEP->getPointerOperand(); - } else if (Operator::getOpcode(V) == Instruction::BitCast) { - V = cast<Operator>(V)->getOperand(0); - } else if (GlobalAlias *GA = dyn_cast<GlobalAlias>(V)) { - if (GA->mayBeOverridden()) - break; - V = GA->getAliasee(); - } else { - break; - } - assert(V->getType()->isPointerTy() && "Unexpected operand type!"); - } while (Visited.insert(V).second); - - Type *IntPtrTy = DL.getIntPtrType(V->getContext()); - return cast<ConstantInt>(ConstantInt::get(IntPtrTy, Offset)); -} - -/// \brief Analyze a call site for potential inlining. -/// -/// Returns true if inlining this call is viable, and false if it is not -/// viable. It computes the cost and adjusts the threshold based on numerous -/// factors and heuristics. If this method returns false but the computed cost -/// is below the computed threshold, then inlining was forcibly disabled by -/// some artifact of the routine. -bool CallAnalyzer::analyzeCall(CallSite CS) { - ++NumCallsAnalyzed; - - // Perform some tweaks to the cost and threshold based on the direct - // callsite information. - - // We want to more aggressively inline vector-dense kernels, so up the - // threshold, and we'll lower it if the % of vector instructions gets too - // low. Note that these bonuses are some what arbitrary and evolved over time - // by accident as much as because they are principled bonuses. - // - // FIXME: It would be nice to remove all such bonuses. At least it would be - // nice to base the bonus values on something more scientific. - assert(NumInstructions == 0); - assert(NumVectorInstructions == 0); - FiftyPercentVectorBonus = 3 * Threshold / 2; - TenPercentVectorBonus = 3 * Threshold / 4; - const DataLayout &DL = F.getParent()->getDataLayout(); - - // Track whether the post-inlining function would have more than one basic - // block. A single basic block is often intended for inlining. Balloon the - // threshold by 50% until we pass the single-BB phase. - bool SingleBB = true; - int SingleBBBonus = Threshold / 2; - - // Speculatively apply all possible bonuses to Threshold. If cost exceeds - // this Threshold any time, and cost cannot decrease, we can stop processing - // the rest of the function body. - Threshold += (SingleBBBonus + FiftyPercentVectorBonus); - - // Give out bonuses per argument, as the instructions setting them up will - // be gone after inlining. - for (unsigned I = 0, E = CS.arg_size(); I != E; ++I) { - if (CS.isByValArgument(I)) { - // We approximate the number of loads and stores needed by dividing the - // size of the byval type by the target's pointer size. - PointerType *PTy = cast<PointerType>(CS.getArgument(I)->getType()); - unsigned TypeSize = DL.getTypeSizeInBits(PTy->getElementType()); - unsigned PointerSize = DL.getPointerSizeInBits(); - // Ceiling division. - unsigned NumStores = (TypeSize + PointerSize - 1) / PointerSize; - - // If it generates more than 8 stores it is likely to be expanded as an - // inline memcpy so we take that as an upper bound. Otherwise we assume - // one load and one store per word copied. - // FIXME: The maxStoresPerMemcpy setting from the target should be used - // here instead of a magic number of 8, but it's not available via - // DataLayout. - NumStores = std::min(NumStores, 8U); - - Cost -= 2 * NumStores * InlineConstants::InstrCost; - } else { - // For non-byval arguments subtract off one instruction per call - // argument. - Cost -= InlineConstants::InstrCost; - } - } - - // If there is only one call of the function, and it has internal linkage, - // the cost of inlining it drops dramatically. - bool OnlyOneCallAndLocalLinkage = F.hasLocalLinkage() && F.hasOneUse() && - &F == CS.getCalledFunction(); - if (OnlyOneCallAndLocalLinkage) - Cost += InlineConstants::LastCallToStaticBonus; - - // If the instruction after the call, or if the normal destination of the - // invoke is an unreachable instruction, the function is noreturn. As such, - // there is little point in inlining this unless there is literally zero - // cost. - Instruction *Instr = CS.getInstruction(); - if (InvokeInst *II = dyn_cast<InvokeInst>(Instr)) { - if (isa<UnreachableInst>(II->getNormalDest()->begin())) - Threshold = 0; - } else if (isa<UnreachableInst>(++BasicBlock::iterator(Instr))) - Threshold = 0; - - // If this function uses the coldcc calling convention, prefer not to inline - // it. - if (F.getCallingConv() == CallingConv::Cold) - Cost += InlineConstants::ColdccPenalty; - - // Check if we're done. This can happen due to bonuses and penalties. - if (Cost > Threshold) - return false; - - if (F.empty()) - return true; - - Function *Caller = CS.getInstruction()->getParent()->getParent(); - // Check if the caller function is recursive itself. - for (User *U : Caller->users()) { - CallSite Site(U); - if (!Site) - continue; - Instruction *I = Site.getInstruction(); - if (I->getParent()->getParent() == Caller) { - IsCallerRecursive = true; - break; - } - } - - // Populate our simplified values by mapping from function arguments to call - // arguments with known important simplifications. - CallSite::arg_iterator CAI = CS.arg_begin(); - for (Function::arg_iterator FAI = F.arg_begin(), FAE = F.arg_end(); - FAI != FAE; ++FAI, ++CAI) { - assert(CAI != CS.arg_end()); - if (Constant *C = dyn_cast<Constant>(CAI)) - SimplifiedValues[FAI] = C; - - Value *PtrArg = *CAI; - if (ConstantInt *C = stripAndComputeInBoundsConstantOffsets(PtrArg)) { - ConstantOffsetPtrs[FAI] = std::make_pair(PtrArg, C->getValue()); - - // We can SROA any pointer arguments derived from alloca instructions. - if (isa<AllocaInst>(PtrArg)) { - SROAArgValues[FAI] = PtrArg; - SROAArgCosts[PtrArg] = 0; - } - } - } - NumConstantArgs = SimplifiedValues.size(); - NumConstantOffsetPtrArgs = ConstantOffsetPtrs.size(); - NumAllocaArgs = SROAArgValues.size(); - - // FIXME: If a caller has multiple calls to a callee, we end up recomputing - // the ephemeral values multiple times (and they're completely determined by - // the callee, so this is purely duplicate work). - SmallPtrSet<const Value *, 32> EphValues; - CodeMetrics::collectEphemeralValues(&F, &ACT->getAssumptionCache(F), EphValues); - - // The worklist of live basic blocks in the callee *after* inlining. We avoid - // adding basic blocks of the callee which can be proven to be dead for this - // particular call site in order to get more accurate cost estimates. This - // requires a somewhat heavyweight iteration pattern: we need to walk the - // basic blocks in a breadth-first order as we insert live successors. To - // accomplish this, prioritizing for small iterations because we exit after - // crossing our threshold, we use a small-size optimized SetVector. - typedef SetVector<BasicBlock *, SmallVector<BasicBlock *, 16>, - SmallPtrSet<BasicBlock *, 16> > BBSetVector; - BBSetVector BBWorklist; - BBWorklist.insert(&F.getEntryBlock()); - // Note that we *must not* cache the size, this loop grows the worklist. - for (unsigned Idx = 0; Idx != BBWorklist.size(); ++Idx) { - // Bail out the moment we cross the threshold. This means we'll under-count - // the cost, but only when undercounting doesn't matter. - if (Cost > Threshold) - break; - - BasicBlock *BB = BBWorklist[Idx]; - if (BB->empty()) - continue; - - // Disallow inlining a blockaddress. A blockaddress only has defined - // behavior for an indirect branch in the same function, and we do not - // currently support inlining indirect branches. But, the inliner may not - // see an indirect branch that ends up being dead code at a particular call - // site. If the blockaddress escapes the function, e.g., via a global - // variable, inlining may lead to an invalid cross-function reference. - if (BB->hasAddressTaken()) - return false; - - // Analyze the cost of this block. If we blow through the threshold, this - // returns false, and we can bail on out. - if (!analyzeBlock(BB, EphValues)) { - if (IsRecursiveCall || ExposesReturnsTwice || HasDynamicAlloca || - HasIndirectBr || HasFrameEscape) - return false; - - // If the caller is a recursive function then we don't want to inline - // functions which allocate a lot of stack space because it would increase - // the caller stack usage dramatically. - if (IsCallerRecursive && - AllocatedSize > InlineConstants::TotalAllocaSizeRecursiveCaller) - return false; - - break; - } - - TerminatorInst *TI = BB->getTerminator(); - - // Add in the live successors by first checking whether we have terminator - // that may be simplified based on the values simplified by this call. - if (BranchInst *BI = dyn_cast<BranchInst>(TI)) { - if (BI->isConditional()) { - Value *Cond = BI->getCondition(); - if (ConstantInt *SimpleCond - = dyn_cast_or_null<ConstantInt>(SimplifiedValues.lookup(Cond))) { - BBWorklist.insert(BI->getSuccessor(SimpleCond->isZero() ? 1 : 0)); - continue; - } - } - } else if (SwitchInst *SI = dyn_cast<SwitchInst>(TI)) { - Value *Cond = SI->getCondition(); - if (ConstantInt *SimpleCond - = dyn_cast_or_null<ConstantInt>(SimplifiedValues.lookup(Cond))) { - BBWorklist.insert(SI->findCaseValue(SimpleCond).getCaseSuccessor()); - continue; - } - } - - // If we're unable to select a particular successor, just count all of - // them. - for (unsigned TIdx = 0, TSize = TI->getNumSuccessors(); TIdx != TSize; - ++TIdx) - BBWorklist.insert(TI->getSuccessor(TIdx)); - - // If we had any successors at this point, than post-inlining is likely to - // have them as well. Note that we assume any basic blocks which existed - // due to branches or switches which folded above will also fold after - // inlining. - if (SingleBB && TI->getNumSuccessors() > 1) { - // Take off the bonus we applied to the threshold. - Threshold -= SingleBBBonus; - SingleBB = false; - } - } - - // If this is a noduplicate call, we can still inline as long as - // inlining this would cause the removal of the caller (so the instruction - // is not actually duplicated, just moved). - if (!OnlyOneCallAndLocalLinkage && ContainsNoDuplicateCall) - return false; - - // We applied the maximum possible vector bonus at the beginning. Now, - // subtract the excess bonus, if any, from the Threshold before - // comparing against Cost. - if (NumVectorInstructions <= NumInstructions / 10) - Threshold -= FiftyPercentVectorBonus; - else if (NumVectorInstructions <= NumInstructions / 2) - Threshold -= (FiftyPercentVectorBonus - TenPercentVectorBonus); - - return Cost < Threshold; -} - -#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) -/// \brief Dump stats about this call's analysis. -void CallAnalyzer::dump() { -#define DEBUG_PRINT_STAT(x) dbgs() << " " #x ": " << x << "\n" - DEBUG_PRINT_STAT(NumConstantArgs); - DEBUG_PRINT_STAT(NumConstantOffsetPtrArgs); - DEBUG_PRINT_STAT(NumAllocaArgs); - DEBUG_PRINT_STAT(NumConstantPtrCmps); - DEBUG_PRINT_STAT(NumConstantPtrDiffs); - DEBUG_PRINT_STAT(NumInstructionsSimplified); - DEBUG_PRINT_STAT(NumInstructions); - DEBUG_PRINT_STAT(SROACostSavings); - DEBUG_PRINT_STAT(SROACostSavingsLost); - DEBUG_PRINT_STAT(ContainsNoDuplicateCall); - DEBUG_PRINT_STAT(Cost); - DEBUG_PRINT_STAT(Threshold); -#undef DEBUG_PRINT_STAT -} -#endif - -INITIALIZE_PASS_BEGIN(InlineCostAnalysis, "inline-cost", "Inline Cost Analysis", - true, true) -INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass) -INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker) -INITIALIZE_PASS_END(InlineCostAnalysis, "inline-cost", "Inline Cost Analysis", - true, true) - -char InlineCostAnalysis::ID = 0; - -InlineCostAnalysis::InlineCostAnalysis() : CallGraphSCCPass(ID) {} - -InlineCostAnalysis::~InlineCostAnalysis() {} - -void InlineCostAnalysis::getAnalysisUsage(AnalysisUsage &AU) const { - AU.setPreservesAll(); - AU.addRequired<AssumptionCacheTracker>(); - AU.addRequired<TargetTransformInfoWrapperPass>(); - CallGraphSCCPass::getAnalysisUsage(AU); -} - -bool InlineCostAnalysis::runOnSCC(CallGraphSCC &SCC) { - TTIWP = &getAnalysis<TargetTransformInfoWrapperPass>(); - ACT = &getAnalysis<AssumptionCacheTracker>(); - return false; -} - -InlineCost InlineCostAnalysis::getInlineCost(CallSite CS, int Threshold) { - return getInlineCost(CS, CS.getCalledFunction(), Threshold); -} - -/// \brief Test that two functions either have or have not the given attribute -/// at the same time. -template<typename AttrKind> -static bool attributeMatches(Function *F1, Function *F2, AttrKind Attr) { - return F1->getFnAttribute(Attr) == F2->getFnAttribute(Attr); -} - -/// \brief Test that there are no attribute conflicts between Caller and Callee -/// that prevent inlining. -static bool functionsHaveCompatibleAttributes(Function *Caller, - Function *Callee, - TargetTransformInfo &TTI) { - return TTI.hasCompatibleFunctionAttributes(Caller, Callee) && - attributeMatches(Caller, Callee, Attribute::SanitizeAddress) && - attributeMatches(Caller, Callee, Attribute::SanitizeMemory) && - attributeMatches(Caller, Callee, Attribute::SanitizeThread); -} - -InlineCost InlineCostAnalysis::getInlineCost(CallSite CS, Function *Callee, - int Threshold) { - // Cannot inline indirect calls. - if (!Callee) - return llvm::InlineCost::getNever(); - - // Calls to functions with always-inline attributes should be inlined - // whenever possible. - if (CS.hasFnAttr(Attribute::AlwaysInline)) { - if (isInlineViable(*Callee)) - return llvm::InlineCost::getAlways(); - return llvm::InlineCost::getNever(); - } - - // Never inline functions with conflicting attributes (unless callee has - // always-inline attribute). - if (!functionsHaveCompatibleAttributes(CS.getCaller(), Callee, - TTIWP->getTTI(*Callee))) - return llvm::InlineCost::getNever(); - - // Don't inline this call if the caller has the optnone attribute. - if (CS.getCaller()->hasFnAttribute(Attribute::OptimizeNone)) - return llvm::InlineCost::getNever(); - - // Don't inline functions which can be redefined at link-time to mean - // something else. Don't inline functions marked noinline or call sites - // marked noinline. - if (Callee->mayBeOverridden() || - Callee->hasFnAttribute(Attribute::NoInline) || CS.isNoInline()) - return llvm::InlineCost::getNever(); - - DEBUG(llvm::dbgs() << " Analyzing call of " << Callee->getName() - << "...\n"); - - CallAnalyzer CA(TTIWP->getTTI(*Callee), ACT, *Callee, Threshold, CS); - bool ShouldInline = CA.analyzeCall(CS); - - DEBUG(CA.dump()); - - // Check if there was a reason to force inlining or no inlining. - if (!ShouldInline && CA.getCost() < CA.getThreshold()) - return InlineCost::getNever(); - if (ShouldInline && CA.getCost() >= CA.getThreshold()) - return InlineCost::getAlways(); - - return llvm::InlineCost::get(CA.getCost(), CA.getThreshold()); -} - -bool InlineCostAnalysis::isInlineViable(Function &F) { - bool ReturnsTwice = F.hasFnAttribute(Attribute::ReturnsTwice); - for (Function::iterator BI = F.begin(), BE = F.end(); BI != BE; ++BI) { - // Disallow inlining of functions which contain indirect branches or - // blockaddresses. - if (isa<IndirectBrInst>(BI->getTerminator()) || BI->hasAddressTaken()) - return false; - - for (BasicBlock::iterator II = BI->begin(), IE = BI->end(); II != IE; - ++II) { - CallSite CS(II); - if (!CS) - continue; - - // Disallow recursive calls. - if (&F == CS.getCalledFunction()) - return false; - - // Disallow calls which expose returns-twice to a function not previously - // attributed as such. - if (!ReturnsTwice && CS.isCall() && - cast<CallInst>(CS.getInstruction())->canReturnTwice()) - return false; - - // Disallow inlining functions that call @llvm.localescape. Doing this - // correctly would require major changes to the inliner. - if (CS.getCalledFunction() && - CS.getCalledFunction()->getIntrinsicID() == - llvm::Intrinsic::localescape) - return false; - } - } - - return true; -} |
