X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTransforms%2FIPO%2FArgumentPromotion.cpp;h=bdd1b61f9b2b1ec8161a8bf70417d0e91b290ea1;hb=f73144bb0330cc615083dd20a550fecdfd0fa4c4;hp=712deb467fbbf4ff15704b83ab68aa3d4e971254;hpb=d13db2c59cc94162d6cf0a04187d408bfef6d4a7;p=oota-llvm.git diff --git a/lib/Transforms/IPO/ArgumentPromotion.cpp b/lib/Transforms/IPO/ArgumentPromotion.cpp index 712deb467fb..bdd1b61f9b2 100644 --- a/lib/Transforms/IPO/ArgumentPromotion.cpp +++ b/lib/Transforms/IPO/ArgumentPromotion.cpp @@ -29,27 +29,33 @@ // //===----------------------------------------------------------------------===// -#define DEBUG_TYPE "argpromotion" #include "llvm/Transforms/IPO.h" -#include "llvm/Constants.h" -#include "llvm/DerivedTypes.h" -#include "llvm/Module.h" -#include "llvm/CallGraphSCCPass.h" -#include "llvm/Instructions.h" -#include "llvm/LLVMContext.h" +#include "llvm/ADT/DepthFirstIterator.h" +#include "llvm/ADT/Statistic.h" +#include "llvm/ADT/StringExtras.h" #include "llvm/Analysis/AliasAnalysis.h" +#include "llvm/Analysis/AssumptionCache.h" +#include "llvm/Analysis/BasicAliasAnalysis.h" #include "llvm/Analysis/CallGraph.h" -#include "llvm/Target/TargetData.h" -#include "llvm/Support/CallSite.h" -#include "llvm/Support/CFG.h" +#include "llvm/Analysis/CallGraphSCCPass.h" +#include "llvm/Analysis/TargetLibraryInfo.h" +#include "llvm/Analysis/ValueTracking.h" +#include "llvm/IR/CFG.h" +#include "llvm/IR/CallSite.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/DebugInfo.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/Module.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" -#include "llvm/ADT/DepthFirstIterator.h" -#include "llvm/ADT/Statistic.h" -#include "llvm/ADT/StringExtras.h" #include using namespace llvm; +#define DEBUG_TYPE "argpromotion" + STATISTIC(NumArgumentsPromoted , "Number of pointer arguments promoted"); STATISTIC(NumAggregatesPromoted, "Number of aggregate arguments promoted"); STATISTIC(NumByValArgsPromoted , "Number of byval arguments promoted"); @@ -59,33 +65,48 @@ namespace { /// ArgPromotion - The 'by reference' to 'by value' argument promotion pass. /// struct ArgPromotion : public CallGraphSCCPass { - virtual void getAnalysisUsage(AnalysisUsage &AU) const { - AU.addRequired(); + void getAnalysisUsage(AnalysisUsage &AU) const override { + AU.addRequired(); + AU.addRequired(); CallGraphSCCPass::getAnalysisUsage(AU); } - virtual bool runOnSCC(CallGraphSCC &SCC); + bool runOnSCC(CallGraphSCC &SCC) override; static char ID; // Pass identification, replacement for typeid explicit ArgPromotion(unsigned maxElements = 3) - : CallGraphSCCPass(&ID), maxElements(maxElements) {} + : CallGraphSCCPass(ID), maxElements(maxElements) { + initializeArgPromotionPass(*PassRegistry::getPassRegistry()); + } /// A vector used to hold the indices of a single GEP instruction typedef std::vector IndicesVector; private: + bool isDenselyPacked(Type *type, const DataLayout &DL); + bool canPaddingBeAccessed(Argument *Arg); CallGraphNode *PromoteArguments(CallGraphNode *CGN); - bool isSafeToPromoteArgument(Argument *Arg, bool isByVal) const; + bool isSafeToPromoteArgument(Argument *Arg, bool isByVal, + AAResults &AAR) const; CallGraphNode *DoPromotion(Function *F, - SmallPtrSet &ArgsToPromote, - SmallPtrSet &ByValArgsToTransform); + SmallPtrSetImpl &ArgsToPromote, + SmallPtrSetImpl &ByValArgsToTransform); + + using llvm::Pass::doInitialization; + bool doInitialization(CallGraph &CG) override; /// The maximum number of elements to expand, or 0 for unlimited. unsigned maxElements; + DenseMap FunctionDIs; }; } char ArgPromotion::ID = 0; -INITIALIZE_PASS(ArgPromotion, "argpromotion", - "Promote 'by reference' arguments to scalars", false, false); +INITIALIZE_PASS_BEGIN(ArgPromotion, "argpromotion", + "Promote 'by reference' arguments to scalars", false, false) +INITIALIZE_PASS_DEPENDENCY(AssumptionCacheTracker) +INITIALIZE_PASS_DEPENDENCY(CallGraphWrapperPass) +INITIALIZE_PASS_DEPENDENCY(TargetLibraryInfoWrapperPass) +INITIALIZE_PASS_END(ArgPromotion, "argpromotion", + "Promote 'by reference' arguments to scalars", false, false) Pass *llvm::createArgumentPromotionPass(unsigned maxElements) { return new ArgPromotion(maxElements); @@ -109,6 +130,79 @@ bool ArgPromotion::runOnSCC(CallGraphSCC &SCC) { return Changed; } +/// \brief Checks if a type could have padding bytes. +bool ArgPromotion::isDenselyPacked(Type *type, const DataLayout &DL) { + + // There is no size information, so be conservative. + if (!type->isSized()) + return false; + + // If the alloc size is not equal to the storage size, then there are padding + // bytes. For x86_fp80 on x86-64, size: 80 alloc size: 128. + if (DL.getTypeSizeInBits(type) != DL.getTypeAllocSizeInBits(type)) + return false; + + if (!isa(type)) + return true; + + // For homogenous sequential types, check for padding within members. + if (SequentialType *seqTy = dyn_cast(type)) + return isa(seqTy) || + isDenselyPacked(seqTy->getElementType(), DL); + + // Check for padding within and between elements of a struct. + StructType *StructTy = cast(type); + const StructLayout *Layout = DL.getStructLayout(StructTy); + uint64_t StartPos = 0; + for (unsigned i = 0, E = StructTy->getNumElements(); i < E; ++i) { + Type *ElTy = StructTy->getElementType(i); + if (!isDenselyPacked(ElTy, DL)) + return false; + if (StartPos != Layout->getElementOffsetInBits(i)) + return false; + StartPos += DL.getTypeAllocSizeInBits(ElTy); + } + + return true; +} + +/// \brief Checks if the padding bytes of an argument could be accessed. +bool ArgPromotion::canPaddingBeAccessed(Argument *arg) { + + assert(arg->hasByValAttr()); + + // Track all the pointers to the argument to make sure they are not captured. + SmallPtrSet PtrValues; + PtrValues.insert(arg); + + // Track all of the stores. + SmallVector Stores; + + // Scan through the uses recursively to make sure the pointer is always used + // sanely. + SmallVector WorkList; + WorkList.insert(WorkList.end(), arg->user_begin(), arg->user_end()); + while (!WorkList.empty()) { + Value *V = WorkList.back(); + WorkList.pop_back(); + if (isa(V) || isa(V)) { + if (PtrValues.insert(V).second) + WorkList.insert(WorkList.end(), V->user_begin(), V->user_end()); + } else if (StoreInst *Store = dyn_cast(V)) { + Stores.push_back(Store); + } else if (!isa(V)) { + return true; + } + } + +// Check to make sure the pointers aren't captured + for (StoreInst *Store : Stores) + if (PtrValues.count(Store->getValueOperand())) + return true; + + return false; +} + /// PromoteArguments - This method checks the specified function to see if there /// are any promotable arguments and if it is safe to promote the function (for /// example, all callers are direct). If safe to promote some arguments, it @@ -118,100 +212,149 @@ CallGraphNode *ArgPromotion::PromoteArguments(CallGraphNode *CGN) { Function *F = CGN->getFunction(); // Make sure that it is local to this module. - if (!F || !F->hasLocalLinkage()) return 0; + if (!F || !F->hasLocalLinkage()) return nullptr; + + // Don't promote arguments for variadic functions. Adding, removing, or + // changing non-pack parameters can change the classification of pack + // parameters. Frontends encode that classification at the call site in the + // IR, while in the callee the classification is determined dynamically based + // on the number of registers consumed so far. + if (F->isVarArg()) return nullptr; // First check: see if there are any pointer arguments! If not, quick exit. - SmallVector, 16> PointerArgs; - unsigned ArgNo = 0; - for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); - I != E; ++I, ++ArgNo) - if (I->getType()->isPointerTy()) - PointerArgs.push_back(std::pair(I, ArgNo)); - if (PointerArgs.empty()) return 0; + SmallVector PointerArgs; + for (Argument &I : F->args()) + if (I.getType()->isPointerTy()) + PointerArgs.push_back(&I); + if (PointerArgs.empty()) return nullptr; // Second check: make sure that all callers are direct callers. We can't - // transform functions that have indirect callers. - if (F->hasAddressTaken()) - return 0; + // transform functions that have indirect callers. Also see if the function + // is self-recursive. + bool isSelfRecursive = false; + for (Use &U : F->uses()) { + CallSite CS(U.getUser()); + // Must be a direct call. + if (CS.getInstruction() == nullptr || !CS.isCallee(&U)) return nullptr; + + if (CS.getInstruction()->getParent()->getParent() == F) + isSelfRecursive = true; + } + + const DataLayout &DL = F->getParent()->getDataLayout(); + + // We need to manually construct BasicAA directly in order to disable its use + // of other function analyses. + BasicAAResult BAR(createLegacyPMBasicAAResult(*this, *F)); + + // Construct our own AA results for this function. We do this manually to + // work around the limitations of the legacy pass manager. + AAResults AAR(createLegacyPMAAResults(*this, *F, BAR)); // Check to see which arguments are promotable. If an argument is promotable, // add it to ArgsToPromote. SmallPtrSet ArgsToPromote; SmallPtrSet ByValArgsToTransform; - for (unsigned i = 0; i != PointerArgs.size(); ++i) { - bool isByVal = F->paramHasAttr(PointerArgs[i].second+1, Attribute::ByVal); + for (unsigned i = 0, e = PointerArgs.size(); i != e; ++i) { + Argument *PtrArg = PointerArgs[i]; + Type *AgTy = cast(PtrArg->getType())->getElementType(); + + // Replace sret attribute with noalias. This reduces register pressure by + // avoiding a register copy. + if (PtrArg->hasStructRetAttr()) { + unsigned ArgNo = PtrArg->getArgNo(); + F->setAttributes( + F->getAttributes() + .removeAttribute(F->getContext(), ArgNo + 1, Attribute::StructRet) + .addAttribute(F->getContext(), ArgNo + 1, Attribute::NoAlias)); + for (Use &U : F->uses()) { + CallSite CS(U.getUser()); + CS.setAttributes( + CS.getAttributes() + .removeAttribute(F->getContext(), ArgNo + 1, + Attribute::StructRet) + .addAttribute(F->getContext(), ArgNo + 1, Attribute::NoAlias)); + } + } // If this is a byval argument, and if the aggregate type is small, just - // pass the elements, which is always safe. - Argument *PtrArg = PointerArgs[i].first; - if (isByVal) { - const Type *AgTy = cast(PtrArg->getType())->getElementType(); - if (const StructType *STy = dyn_cast(AgTy)) { + // pass the elements, which is always safe, if the passed value is densely + // packed or if we can prove the padding bytes are never accessed. This does + // not apply to inalloca. + bool isSafeToPromote = + PtrArg->hasByValAttr() && + (isDenselyPacked(AgTy, DL) || !canPaddingBeAccessed(PtrArg)); + if (isSafeToPromote) { + if (StructType *STy = dyn_cast(AgTy)) { if (maxElements > 0 && STy->getNumElements() > maxElements) { DEBUG(dbgs() << "argpromotion disable promoting argument '" << PtrArg->getName() << "' because it would require adding more" << " than " << maxElements << " arguments to the function.\n"); - } else { - // If all the elements are single-value types, we can promote it. - bool AllSimple = true; - for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) - if (!STy->getElementType(i)->isSingleValueType()) { - AllSimple = false; - break; - } - - // Safe to transform, don't even bother trying to "promote" it. - // Passing the elements as a scalar will allow scalarrepl to hack on - // the new alloca we introduce. - if (AllSimple) { - ByValArgsToTransform.insert(PtrArg); - continue; + continue; + } + + // If all the elements are single-value types, we can promote it. + bool AllSimple = true; + for (const auto *EltTy : STy->elements()) { + if (!EltTy->isSingleValueType()) { + AllSimple = false; + break; } } + + // Safe to transform, don't even bother trying to "promote" it. + // Passing the elements as a scalar will allow scalarrepl to hack on + // the new alloca we introduce. + if (AllSimple) { + ByValArgsToTransform.insert(PtrArg); + continue; + } } } + // If the argument is a recursive type and we're in a recursive + // function, we could end up infinitely peeling the function argument. + if (isSelfRecursive) { + if (StructType *STy = dyn_cast(AgTy)) { + bool RecursiveType = false; + for (const auto *EltTy : STy->elements()) { + if (EltTy == PtrArg->getType()) { + RecursiveType = true; + break; + } + } + if (RecursiveType) + continue; + } + } + // Otherwise, see if we can promote the pointer to its value. - if (isSafeToPromoteArgument(PtrArg, isByVal)) + if (isSafeToPromoteArgument(PtrArg, PtrArg->hasByValOrInAllocaAttr(), AAR)) ArgsToPromote.insert(PtrArg); } // No promotable pointer arguments. if (ArgsToPromote.empty() && ByValArgsToTransform.empty()) - return 0; + return nullptr; return DoPromotion(F, ArgsToPromote, ByValArgsToTransform); } -/// IsAlwaysValidPointer - Return true if the specified pointer is always legal -/// to load. -static bool IsAlwaysValidPointer(Value *V) { - if (isa(V) || isa(V)) return true; - if (GetElementPtrInst *GEP = dyn_cast(V)) - return IsAlwaysValidPointer(GEP->getOperand(0)); - if (ConstantExpr *CE = dyn_cast(V)) - if (CE->getOpcode() == Instruction::GetElementPtr) - return IsAlwaysValidPointer(CE->getOperand(0)); - - return false; -} - -/// AllCalleesPassInValidPointerForArgument - Return true if we can prove that +/// AllCallersPassInValidPointerForArgument - Return true if we can prove that /// all callees pass in a valid pointer for the specified function argument. -static bool AllCalleesPassInValidPointerForArgument(Argument *Arg) { +static bool AllCallersPassInValidPointerForArgument(Argument *Arg) { Function *Callee = Arg->getParent(); + const DataLayout &DL = Callee->getParent()->getDataLayout(); - unsigned ArgNo = std::distance(Callee->arg_begin(), - Function::arg_iterator(Arg)); + unsigned ArgNo = Arg->getArgNo(); // Look at all call sites of the function. At this pointer we know we only // have direct callees. - for (Value::use_iterator UI = Callee->use_begin(), E = Callee->use_end(); - UI != E; ++UI) { - CallSite CS = CallSite::get(*UI); - assert(CS.getInstruction() && "Should only have direct calls!"); + for (User *U : Callee->users()) { + CallSite CS(U); + assert(CS && "Should only have direct calls!"); - if (!IsAlwaysValidPointer(CS.getArgument(ArgNo))) + if (!isDereferenceablePointer(CS.getArgument(ArgNo), DL)) return false; } return true; @@ -226,10 +369,7 @@ static bool IsPrefix(const ArgPromotion::IndicesVector &Prefix, const ArgPromotion::IndicesVector &Longer) { if (Prefix.size() > Longer.size()) return false; - for (unsigned i = 0, e = Prefix.size(); i != e; ++i) - if (Prefix[i] != Longer[i]) - return false; - return true; + return std::equal(Prefix.begin(), Prefix.end(), Longer.begin()); } @@ -289,7 +429,9 @@ static void MarkIndicesSafe(const ArgPromotion::IndicesVector &ToMark, /// This method limits promotion of aggregates to only promote up to three /// elements of the aggregate in order to avoid exploding the number of /// arguments passed in. -bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { +bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, + bool isByValOrInAlloca, + AAResults &AAR) const { typedef std::set GEPIndicesSet; // Quick exit for unused arguments @@ -311,6 +453,9 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { // // This set will contain all sets of indices that are loaded in the entry // block, and thus are safe to unconditionally load in the caller. + // + // This optimization is also safe for InAlloca parameters, because it verifies + // that the address isn't captured. GEPIndicesSet SafeToUnconditionallyLoad; // This set contains all the sets of indices that we are planning to promote. @@ -318,17 +463,16 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { GEPIndicesSet ToPromote; // If the pointer is always valid, any load with first index 0 is valid. - if (isByVal || AllCalleesPassInValidPointerForArgument(Arg)) + if (isByValOrInAlloca || AllCallersPassInValidPointerForArgument(Arg)) SafeToUnconditionallyLoad.insert(IndicesVector(1, 0)); // First, iterate the entry block and mark loads of (geps of) arguments as // safe. - BasicBlock *EntryBlock = Arg->getParent()->begin(); + BasicBlock &EntryBlock = Arg->getParent()->front(); // Declare this here so we can reuse it IndicesVector Indices; - for (BasicBlock::iterator I = EntryBlock->begin(), E = EntryBlock->end(); - I != E; ++I) - if (LoadInst *LI = dyn_cast(I)) { + for (Instruction &I : EntryBlock) + if (LoadInst *LI = dyn_cast(&I)) { Value *V = LI->getPointerOperand(); if (GetElementPtrInst *GEP = dyn_cast(V)) { V = GEP->getPointerOperand(); @@ -358,25 +502,24 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { // not (GEP+)loads, or any (GEP+)loads that are not safe to promote. SmallVector Loads; IndicesVector Operands; - for (Value::use_iterator UI = Arg->use_begin(), E = Arg->use_end(); - UI != E; ++UI) { - User *U = *UI; + for (Use &U : Arg->uses()) { + User *UR = U.getUser(); Operands.clear(); - if (LoadInst *LI = dyn_cast(U)) { - if (LI->isVolatile()) return false; // Don't hack volatile loads + if (LoadInst *LI = dyn_cast(UR)) { + // Don't hack volatile/atomic loads + if (!LI->isSimple()) return false; Loads.push_back(LI); // Direct loads are equivalent to a GEP with a zero index and then a load. Operands.push_back(0); - } else if (GetElementPtrInst *GEP = dyn_cast(U)) { + } else if (GetElementPtrInst *GEP = dyn_cast(UR)) { if (GEP->use_empty()) { // Dead GEP's cause trouble later. Just remove them if we run into // them. - getAnalysis().deleteValue(GEP); GEP->eraseFromParent(); // TODO: This runs the above loop over and over again for dead GEPs // Couldn't we just do increment the UI iterator earlier and erase the // use? - return isSafeToPromoteArgument(Arg, isByVal); + return isSafeToPromoteArgument(Arg, isByValOrInAlloca, AAR); } // Ensure that all of the indices are constants. @@ -388,10 +531,10 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { return false; // Not a constant operand GEP! // Ensure that the only users of the GEP are load instructions. - for (Value::use_iterator UI = GEP->use_begin(), E = GEP->use_end(); - UI != E; ++UI) - if (LoadInst *LI = dyn_cast(*UI)) { - if (LI->isVolatile()) return false; // Don't hack volatile loads + for (User *GEPU : GEP->users()) + if (LoadInst *LI = dyn_cast(GEPU)) { + // Don't hack volatile/atomic loads + if (!LI->isSimple()) return false; Loads.push_back(LI); } else { // Other uses than load? @@ -418,7 +561,7 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { // of elements of the aggregate. return false; } - ToPromote.insert(Operands); + ToPromote.insert(std::move(Operands)); } } @@ -433,32 +576,22 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { // blocks we know to be transparent to the load. SmallPtrSet TranspBlocks; - AliasAnalysis &AA = getAnalysis(); - TargetData *TD = getAnalysisIfAvailable(); - if (!TD) return false; // Without TargetData, assume the worst. - for (unsigned i = 0, e = Loads.size(); i != e; ++i) { // Check to see if the load is invalidated from the start of the block to // the load itself. LoadInst *Load = Loads[i]; BasicBlock *BB = Load->getParent(); - const PointerType *LoadTy = - cast(Load->getPointerOperand()->getType()); - unsigned LoadSize =(unsigned)TD->getTypeStoreSize(LoadTy->getElementType()); - - if (AA.canInstructionRangeModify(BB->front(), *Load, Arg, LoadSize)) + MemoryLocation Loc = MemoryLocation::get(Load); + if (AAR.canInstructionRangeModRef(BB->front(), *Load, Loc, MRI_Mod)) return false; // Pointer is invalidated! // Now check every path from the entry block to the load for transparency. // To do this, we perform a depth first search on the inverse CFG from the // loading block. - for (pred_iterator PI = pred_begin(BB), E = pred_end(BB); PI != E; ++PI) { - BasicBlock *P = *PI; - for (idf_ext_iterator > - I = idf_ext_begin(P, TranspBlocks), - E = idf_ext_end(P, TranspBlocks); I != E; ++I) - if (AA.canBasicBlockModify(**I, Arg, LoadSize)) + for (BasicBlock *P : predecessors(BB)) { + for (BasicBlock *TranspBB : inverse_depth_first_ext(P, TranspBlocks)) + if (AAR.canBasicBlockModify(*TranspBB, Loc)) return false; } } @@ -473,15 +606,15 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { /// arguments, and returns the new function. At this point, we know that it's /// safe to do so. CallGraphNode *ArgPromotion::DoPromotion(Function *F, - SmallPtrSet &ArgsToPromote, - SmallPtrSet &ByValArgsToTransform) { + SmallPtrSetImpl &ArgsToPromote, + SmallPtrSetImpl &ByValArgsToTransform) { // Start by computing a new prototype for the function, which is the same as // the old function, but has modified arguments. - const FunctionType *FTy = F->getFunctionType(); - std::vector Params; + FunctionType *FTy = F->getFunctionType(); + std::vector Params; - typedef std::set ScalarizeTable; + typedef std::set> ScalarizeTable; // ScalarizedElements - If we are promoting a pointer that has elements // accessed out of it, keep track of which elements are accessed so that we @@ -495,34 +628,40 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // OriginalLoads - Keep track of a representative load instruction from the // original function so that we can tell the alias analysis implementation // what the new GEP/Load instructions we are inserting look like. - std::map OriginalLoads; + // We need to keep the original loads for each argument and the elements + // of the argument that are accessed. + std::map, LoadInst*> OriginalLoads; - // Attributes - Keep track of the parameter attributes for the arguments + // Attribute - Keep track of the parameter attributes for the arguments // that we are *not* promoting. For the ones that we do promote, the parameter // attributes are lost - SmallVector AttributesVec; - const AttrListPtr &PAL = F->getAttributes(); + SmallVector AttributesVec; + const AttributeSet &PAL = F->getAttributes(); // Add any return attributes. - if (Attributes attrs = PAL.getRetAttributes()) - AttributesVec.push_back(AttributeWithIndex::get(0, attrs)); + if (PAL.hasAttributes(AttributeSet::ReturnIndex)) + AttributesVec.push_back(AttributeSet::get(F->getContext(), + PAL.getRetAttributes())); // First, determine the new argument list unsigned ArgIndex = 1; for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I, ++ArgIndex) { - if (ByValArgsToTransform.count(I)) { + if (ByValArgsToTransform.count(&*I)) { // Simple byval argument? Just add all the struct element types. - const Type *AgTy = cast(I->getType())->getElementType(); - const StructType *STy = cast(AgTy); - for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) - Params.push_back(STy->getElementType(i)); + Type *AgTy = cast(I->getType())->getElementType(); + StructType *STy = cast(AgTy); + Params.insert(Params.end(), STy->element_begin(), STy->element_end()); ++NumByValArgsPromoted; - } else if (!ArgsToPromote.count(I)) { + } else if (!ArgsToPromote.count(&*I)) { // Unchanged argument Params.push_back(I->getType()); - if (Attributes attrs = PAL.getParamAttributes(ArgIndex)) - AttributesVec.push_back(AttributeWithIndex::get(Params.size(), attrs)); + AttributeSet attrs = PAL.getParamAttributes(ArgIndex); + if (attrs.hasAttributes(ArgIndex)) { + AttrBuilder B(attrs, ArgIndex); + AttributesVec. + push_back(AttributeSet::get(F->getContext(), Params.size(), B)); + } } else if (I->use_empty()) { // Dead argument (which are always marked as promotable) ++NumArgumentsDead; @@ -532,43 +671,46 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // In this table, we will track which indices are loaded from the argument // (where direct loads are tracked as no indices). - ScalarizeTable &ArgIndices = ScalarizedElements[I]; - for (Value::use_iterator UI = I->use_begin(), E = I->use_end(); UI != E; - ++UI) { - Instruction *User = cast(*UI); - assert(isa(User) || isa(User)); + ScalarizeTable &ArgIndices = ScalarizedElements[&*I]; + for (User *U : I->users()) { + Instruction *UI = cast(U); + Type *SrcTy; + if (LoadInst *L = dyn_cast(UI)) + SrcTy = L->getType(); + else + SrcTy = cast(UI)->getSourceElementType(); IndicesVector Indices; - Indices.reserve(User->getNumOperands() - 1); + Indices.reserve(UI->getNumOperands() - 1); // Since loads will only have a single operand, and GEPs only a single // non-index operand, this will record direct loads without any indices, // and gep+loads with the GEP indices. - for (User::op_iterator II = User->op_begin() + 1, IE = User->op_end(); + for (User::op_iterator II = UI->op_begin() + 1, IE = UI->op_end(); II != IE; ++II) Indices.push_back(cast(*II)->getSExtValue()); // GEPs with a single 0 index can be merged with direct loads if (Indices.size() == 1 && Indices.front() == 0) Indices.clear(); - ArgIndices.insert(Indices); + ArgIndices.insert(std::make_pair(SrcTy, Indices)); LoadInst *OrigLoad; - if (LoadInst *L = dyn_cast(User)) + if (LoadInst *L = dyn_cast(UI)) OrigLoad = L; else // Take any load, we will use it only to update Alias Analysis - OrigLoad = cast(User->use_back()); - OriginalLoads[Indices] = OrigLoad; + OrigLoad = cast(UI->user_back()); + OriginalLoads[std::make_pair(&*I, Indices)] = OrigLoad; } // Add a parameter to the function for each element passed in. for (ScalarizeTable::iterator SI = ArgIndices.begin(), E = ArgIndices.end(); SI != E; ++SI) { // not allowed to dereference ->begin() if size() is 0 - Params.push_back(GetElementPtrInst::getIndexedType(I->getType(), - SI->begin(), - SI->end())); + Params.push_back(GetElementPtrInst::getIndexedType( + cast(I->getType()->getScalarType())->getElementType(), + SI->second)); assert(Params.back()); } - if (ArgIndices.size() == 1 && ArgIndices.begin()->empty()) + if (ArgIndices.size() == 1 && ArgIndices.begin()->second.empty()) ++NumArgumentsPromoted; else ++NumAggregatesPromoted; @@ -576,18 +718,11 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, } // Add any function attributes. - if (Attributes attrs = PAL.getFnAttributes()) - AttributesVec.push_back(AttributeWithIndex::get(~0, attrs)); - - const Type *RetTy = FTy->getReturnType(); + if (PAL.hasAttributes(AttributeSet::FunctionIndex)) + AttributesVec.push_back(AttributeSet::get(FTy->getContext(), + PAL.getFnAttributes())); - // Work around LLVM bug PR56: the CWriter cannot emit varargs functions which - // have zero fixed arguments. - bool ExtraArgHack = false; - if (Params.empty() && FTy->isVarArg()) { - ExtraArgHack = true; - Params.push_back(Type::getInt32Ty(F->getContext())); - } + Type *RetTy = FTy->getReturnType(); // Construct the new function type using the new arguments. FunctionType *NFTy = FunctionType::get(RetTy, Params, FTy->isVarArg()); @@ -596,44 +731,49 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, Function *NF = Function::Create(NFTy, F->getLinkage(), F->getName()); NF->copyAttributesFrom(F); - + // Patch the pointer to LLVM function in debug info descriptor. + auto DI = FunctionDIs.find(F); + if (DI != FunctionDIs.end()) { + DISubprogram *SP = DI->second; + SP->replaceFunction(NF); + // Ensure the map is updated so it can be reused on subsequent argument + // promotions of the same function. + FunctionDIs.erase(DI); + FunctionDIs[NF] = SP; + } + DEBUG(dbgs() << "ARG PROMOTION: Promoting to:" << *NF << "\n" << "From: " << *F); // Recompute the parameter attributes list based on the new arguments for // the function. - NF->setAttributes(AttrListPtr::get(AttributesVec.begin(), - AttributesVec.end())); + NF->setAttributes(AttributeSet::get(F->getContext(), AttributesVec)); AttributesVec.clear(); - F->getParent()->getFunctionList().insert(F, NF); + F->getParent()->getFunctionList().insert(F->getIterator(), NF); NF->takeName(F); - // Get the alias analysis information that we need to update to reflect our - // changes. - AliasAnalysis &AA = getAnalysis(); - // Get the callgraph information that we need to update to reflect our // changes. - CallGraph &CG = getAnalysis(); - + CallGraph &CG = getAnalysis().getCallGraph(); + // Get a new callgraph node for NF. CallGraphNode *NF_CGN = CG.getOrInsertFunction(NF); - // Loop over all of the callers of the function, transforming the call sites // to pass in the loaded pointers. // SmallVector Args; while (!F->use_empty()) { - CallSite CS = CallSite::get(F->use_back()); + CallSite CS(F->user_back()); assert(CS.getCalledFunction() == F); Instruction *Call = CS.getInstruction(); - const AttrListPtr &CallPAL = CS.getAttributes(); + const AttributeSet &CallPAL = CS.getAttributes(); // Add any return attributes. - if (Attributes attrs = CallPAL.getRetAttributes()) - AttributesVec.push_back(AttributeWithIndex::get(0, attrs)); + if (CallPAL.hasAttributes(AttributeSet::ReturnIndex)) + AttributesVec.push_back(AttributeSet::get(F->getContext(), + CallPAL.getRetAttributes())); // Loop over the operands, inserting GEP and loads in the caller as // appropriate. @@ -641,44 +781,46 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, ArgIndex = 1; for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(); I != E; ++I, ++AI, ++ArgIndex) - if (!ArgsToPromote.count(I) && !ByValArgsToTransform.count(I)) { + if (!ArgsToPromote.count(&*I) && !ByValArgsToTransform.count(&*I)) { Args.push_back(*AI); // Unmodified argument - if (Attributes Attrs = CallPAL.getParamAttributes(ArgIndex)) - AttributesVec.push_back(AttributeWithIndex::get(Args.size(), Attrs)); - - } else if (ByValArgsToTransform.count(I)) { + if (CallPAL.hasAttributes(ArgIndex)) { + AttrBuilder B(CallPAL, ArgIndex); + AttributesVec. + push_back(AttributeSet::get(F->getContext(), Args.size(), B)); + } + } else if (ByValArgsToTransform.count(&*I)) { // Emit a GEP and load for each element of the struct. - const Type *AgTy = cast(I->getType())->getElementType(); - const StructType *STy = cast(AgTy); + Type *AgTy = cast(I->getType())->getElementType(); + StructType *STy = cast(AgTy); Value *Idxs[2] = { - ConstantInt::get(Type::getInt32Ty(F->getContext()), 0), 0 }; + ConstantInt::get(Type::getInt32Ty(F->getContext()), 0), nullptr }; for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { Idxs[1] = ConstantInt::get(Type::getInt32Ty(F->getContext()), i); - Value *Idx = GetElementPtrInst::Create(*AI, Idxs, Idxs+2, - (*AI)->getName()+"."+utostr(i), - Call); + Value *Idx = GetElementPtrInst::Create( + STy, *AI, Idxs, (*AI)->getName() + "." + Twine(i), Call); // TODO: Tell AA about the new values? Args.push_back(new LoadInst(Idx, Idx->getName()+".val", Call)); } } else if (!I->use_empty()) { // Non-dead argument: insert GEPs and loads as appropriate. - ScalarizeTable &ArgIndices = ScalarizedElements[I]; + ScalarizeTable &ArgIndices = ScalarizedElements[&*I]; // Store the Value* version of the indices in here, but declare it now // for reuse. std::vector Ops; for (ScalarizeTable::iterator SI = ArgIndices.begin(), E = ArgIndices.end(); SI != E; ++SI) { Value *V = *AI; - LoadInst *OrigLoad = OriginalLoads[*SI]; - if (!SI->empty()) { - Ops.reserve(SI->size()); - const Type *ElTy = V->getType(); - for (IndicesVector::const_iterator II = SI->begin(), - IE = SI->end(); II != IE; ++II) { + LoadInst *OrigLoad = OriginalLoads[std::make_pair(&*I, SI->second)]; + if (!SI->second.empty()) { + Ops.reserve(SI->second.size()); + Type *ElTy = V->getType(); + for (IndicesVector::const_iterator II = SI->second.begin(), + IE = SI->second.end(); + II != IE; ++II) { // Use i32 to index structs, and i64 for others (pointers/arrays). // This satisfies GEP constraints. - const Type *IdxTy = (ElTy->isStructTy() ? + Type *IdxTy = (ElTy->isStructTy() ? Type::getInt32Ty(F->getContext()) : Type::getInt64Ty(F->getContext())); Ops.push_back(ConstantInt::get(IdxTy, *II)); @@ -686,59 +828,60 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, ElTy = cast(ElTy)->getTypeAtIndex(*II); } // And create a GEP to extract those indices. - V = GetElementPtrInst::Create(V, Ops.begin(), Ops.end(), - V->getName()+".idx", Call); + V = GetElementPtrInst::Create(SI->first, V, Ops, + V->getName() + ".idx", Call); Ops.clear(); - AA.copyValue(OrigLoad->getOperand(0), V); } // Since we're replacing a load make sure we take the alignment // of the previous load. LoadInst *newLoad = new LoadInst(V, V->getName()+".val", Call); newLoad->setAlignment(OrigLoad->getAlignment()); + // Transfer the AA info too. + AAMDNodes AAInfo; + OrigLoad->getAAMetadata(AAInfo); + newLoad->setAAMetadata(AAInfo); + Args.push_back(newLoad); - AA.copyValue(OrigLoad, Args.back()); } } - if (ExtraArgHack) - Args.push_back(Constant::getNullValue(Type::getInt32Ty(F->getContext()))); - // Push any varargs arguments on the list. for (; AI != CS.arg_end(); ++AI, ++ArgIndex) { Args.push_back(*AI); - if (Attributes Attrs = CallPAL.getParamAttributes(ArgIndex)) - AttributesVec.push_back(AttributeWithIndex::get(Args.size(), Attrs)); + if (CallPAL.hasAttributes(ArgIndex)) { + AttrBuilder B(CallPAL, ArgIndex); + AttributesVec. + push_back(AttributeSet::get(F->getContext(), Args.size(), B)); + } } // Add any function attributes. - if (Attributes attrs = CallPAL.getFnAttributes()) - AttributesVec.push_back(AttributeWithIndex::get(~0, attrs)); + if (CallPAL.hasAttributes(AttributeSet::FunctionIndex)) + AttributesVec.push_back(AttributeSet::get(Call->getContext(), + CallPAL.getFnAttributes())); Instruction *New; if (InvokeInst *II = dyn_cast(Call)) { New = InvokeInst::Create(NF, II->getNormalDest(), II->getUnwindDest(), - Args.begin(), Args.end(), "", Call); + Args, "", Call); cast(New)->setCallingConv(CS.getCallingConv()); - cast(New)->setAttributes(AttrListPtr::get(AttributesVec.begin(), - AttributesVec.end())); + cast(New)->setAttributes(AttributeSet::get(II->getContext(), + AttributesVec)); } else { - New = CallInst::Create(NF, Args.begin(), Args.end(), "", Call); + New = CallInst::Create(NF, Args, "", Call); cast(New)->setCallingConv(CS.getCallingConv()); - cast(New)->setAttributes(AttrListPtr::get(AttributesVec.begin(), - AttributesVec.end())); + cast(New)->setAttributes(AttributeSet::get(New->getContext(), + AttributesVec)); if (cast(Call)->isTailCall()) cast(New)->setTailCall(); } + New->setDebugLoc(Call->getDebugLoc()); Args.clear(); AttributesVec.clear(); - // Update the alias analysis implementation to know that we are replacing - // the old call with a new one. - AA.replaceWithNewValue(Call, New); - // Update the callgraph to know that the callsite has been transformed. CallGraphNode *CalleeNode = CG[Call->getParent()->getParent()]; - CalleeNode->replaceCallEdge(Call, New, NF_CGN); + CalleeNode->replaceCallEdge(CS, CallSite(New), NF_CGN); if (!Call->use_empty()) { Call->replaceAllUsesWith(New); @@ -755,72 +898,75 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // function empty. NF->getBasicBlockList().splice(NF->begin(), F->getBasicBlockList()); - // Loop over the argument list, transfering uses of the old arguments over to - // the new arguments, also transfering over the names as well. + // Loop over the argument list, transferring uses of the old arguments over to + // the new arguments, also transferring over the names as well. // for (Function::arg_iterator I = F->arg_begin(), E = F->arg_end(), I2 = NF->arg_begin(); I != E; ++I) { - if (!ArgsToPromote.count(I) && !ByValArgsToTransform.count(I)) { + if (!ArgsToPromote.count(&*I) && !ByValArgsToTransform.count(&*I)) { // If this is an unmodified argument, move the name and users over to the // new version. - I->replaceAllUsesWith(I2); - I2->takeName(I); - AA.replaceWithNewValue(I, I2); + I->replaceAllUsesWith(&*I2); + I2->takeName(&*I); ++I2; continue; } - if (ByValArgsToTransform.count(I)) { + if (ByValArgsToTransform.count(&*I)) { // In the callee, we create an alloca, and store each of the new incoming // arguments into the alloca. - Instruction *InsertPt = NF->begin()->begin(); + Instruction *InsertPt = &NF->begin()->front(); // Just add all the struct element types. - const Type *AgTy = cast(I->getType())->getElementType(); - Value *TheAlloca = new AllocaInst(AgTy, 0, "", InsertPt); - const StructType *STy = cast(AgTy); + Type *AgTy = cast(I->getType())->getElementType(); + Value *TheAlloca = new AllocaInst(AgTy, nullptr, "", InsertPt); + StructType *STy = cast(AgTy); Value *Idxs[2] = { - ConstantInt::get(Type::getInt32Ty(F->getContext()), 0), 0 }; + ConstantInt::get(Type::getInt32Ty(F->getContext()), 0), nullptr }; for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { Idxs[1] = ConstantInt::get(Type::getInt32Ty(F->getContext()), i); - Value *Idx = - GetElementPtrInst::Create(TheAlloca, Idxs, Idxs+2, - TheAlloca->getName()+"."+Twine(i), - InsertPt); + Value *Idx = GetElementPtrInst::Create( + AgTy, TheAlloca, Idxs, TheAlloca->getName() + "." + Twine(i), + InsertPt); I2->setName(I->getName()+"."+Twine(i)); - new StoreInst(I2++, Idx, InsertPt); + new StoreInst(&*I2++, Idx, InsertPt); } // Anything that used the arg should now use the alloca. I->replaceAllUsesWith(TheAlloca); - TheAlloca->takeName(I); - AA.replaceWithNewValue(I, TheAlloca); + TheAlloca->takeName(&*I); + + // If the alloca is used in a call, we must clear the tail flag since + // the callee now uses an alloca from the caller. + for (User *U : TheAlloca->users()) { + CallInst *Call = dyn_cast(U); + if (!Call) + continue; + Call->setTailCall(false); + } continue; } - if (I->use_empty()) { - AA.deleteValue(I); + if (I->use_empty()) continue; - } // Otherwise, if we promoted this argument, then all users are load // instructions (or GEPs with only load users), and all loads should be // using the new argument that we added. - ScalarizeTable &ArgIndices = ScalarizedElements[I]; + ScalarizeTable &ArgIndices = ScalarizedElements[&*I]; while (!I->use_empty()) { - if (LoadInst *LI = dyn_cast(I->use_back())) { - assert(ArgIndices.begin()->empty() && + if (LoadInst *LI = dyn_cast(I->user_back())) { + assert(ArgIndices.begin()->second.empty() && "Load element should sort to front!"); I2->setName(I->getName()+".val"); - LI->replaceAllUsesWith(I2); - AA.replaceWithNewValue(LI, I2); + LI->replaceAllUsesWith(&*I2); LI->eraseFromParent(); DEBUG(dbgs() << "*** Promoted load of argument '" << I->getName() << "' in function '" << F->getName() << "'\n"); } else { - GetElementPtrInst *GEP = cast(I->use_back()); + GetElementPtrInst *GEP = cast(I->user_back()); IndicesVector Operands; Operands.reserve(GEP->getNumIndices()); for (User::op_iterator II = GEP->idx_begin(), IE = GEP->idx_end(); @@ -833,7 +979,7 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, Function::arg_iterator TheArg = I2; for (ScalarizeTable::iterator It = ArgIndices.begin(); - *It != Operands; ++It, ++TheArg) { + It->second != Operands; ++It, ++TheArg) { assert(It != ArgIndices.end() && "GEP not handled??"); } @@ -850,31 +996,18 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // All of the uses must be load instructions. Replace them all with // the argument specified by ArgNo. while (!GEP->use_empty()) { - LoadInst *L = cast(GEP->use_back()); - L->replaceAllUsesWith(TheArg); - AA.replaceWithNewValue(L, TheArg); + LoadInst *L = cast(GEP->user_back()); + L->replaceAllUsesWith(&*TheArg); L->eraseFromParent(); } - AA.deleteValue(GEP); GEP->eraseFromParent(); } } // Increment I2 past all of the arguments added for this promoted pointer. - for (unsigned i = 0, e = ArgIndices.size(); i != e; ++i) - ++I2; + std::advance(I2, ArgIndices.size()); } - // Notify the alias analysis implementation that we inserted a new argument. - if (ExtraArgHack) - AA.copyValue(Constant::getNullValue(Type::getInt32Ty(F->getContext())), - NF->arg_begin()); - - - // Tell the alias analysis that the old function is about to disappear. - AA.replaceWithNewValue(F, NF); - - NF_CGN->stealCalledFunctionsFrom(CG[F]); // Now that the old function is dead, delete it. If there is a dangling @@ -888,3 +1021,8 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, return NF_CGN; } + +bool ArgPromotion::doInitialization(CallGraph &CG) { + FunctionDIs = makeSubprogramMap(CG.getModule()); + return CallGraphSCCPass::doInitialization(CG); +}