X-Git-Url: http://plrg.eecs.uci.edu/git/?p=oota-llvm.git;a=blobdiff_plain;f=lib%2FTransforms%2FIPO%2FArgumentPromotion.cpp;h=c1453e2467bd1d948c194561943ee6878e3ef5e1;hp=0c77e1fd8cff4f7dfdcc155515d62cd41201a13d;hb=0b8c9a80f20772c3793201ab5b251d3520b9cea3;hpb=90c579de5a383cee278acc3f7e7b9d0a656e6a35 diff --git a/lib/Transforms/IPO/ArgumentPromotion.cpp b/lib/Transforms/IPO/ArgumentPromotion.cpp index 0c77e1fd8cf..c1453e2467b 100644 --- a/lib/Transforms/IPO/ArgumentPromotion.cpp +++ b/lib/Transforms/IPO/ArgumentPromotion.cpp @@ -31,22 +31,21 @@ #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/CallGraph.h" -#include "llvm/Target/TargetData.h" -#include "llvm/Support/CallSite.h" +#include "llvm/CallGraphSCCPass.h" +#include "llvm/IR/Constants.h" +#include "llvm/IR/DerivedTypes.h" +#include "llvm/IR/Instructions.h" +#include "llvm/IR/LLVMContext.h" +#include "llvm/IR/Module.h" #include "llvm/Support/CFG.h" +#include "llvm/Support/CallSite.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; @@ -67,7 +66,9 @@ namespace { virtual bool runOnSCC(CallGraphSCC &SCC); 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; @@ -84,8 +85,12 @@ namespace { } 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_AG_DEPENDENCY(AliasAnalysis) +INITIALIZE_AG_DEPENDENCY(CallGraph) +INITIALIZE_PASS_END(ArgPromotion, "argpromotion", + "Promote 'by reference' arguments to scalars", false, false) Pass *llvm::createArgumentPromotionPass(unsigned maxElements) { return new ArgPromotion(maxElements); @@ -130,47 +135,75 @@ CallGraphNode *ArgPromotion::PromoteArguments(CallGraphNode *CGN) { if (PointerArgs.empty()) return 0; // 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 (Value::use_iterator UI = F->use_begin(), E = F->use_end(); + UI != E; ++UI) { + CallSite CS(*UI); + // Must be a direct call. + if (CS.getInstruction() == 0 || !CS.isCallee(UI)) return 0; + + if (CS.getInstruction()->getParent()->getParent() == F) + isSelfRecursive = true; + } + // 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); + bool isByVal=F->getAttributes(). + hasAttribute(PointerArgs[i].second+1, Attribute::ByVal); + Argument *PtrArg = PointerArgs[i].first; + Type *AgTy = cast(PtrArg->getType())->getElementType(); // 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)) { + 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 (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; + } } } + // 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 (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) { + if (STy->getElementType(i) == PtrArg->getType()) { + RecursiveType = true; + break; + } + } + if (RecursiveType) + continue; + } + } + // Otherwise, see if we can promote the pointer to its value. if (isSafeToPromoteArgument(PtrArg, isByVal)) ArgsToPromote.insert(PtrArg); @@ -183,22 +216,9 @@ CallGraphNode *ArgPromotion::PromoteArguments(CallGraphNode *CGN) { 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(); unsigned ArgNo = std::distance(Callee->arg_begin(), @@ -211,7 +231,7 @@ static bool AllCalleesPassInValidPointerForArgument(Argument *Arg) { CallSite CS(*UI); assert(CS && "Should only have direct calls!"); - if (!IsAlwaysValidPointer(CS.getArgument(ArgNo))) + if (!CS.getArgument(ArgNo)->isDereferenceablePointer()) return false; } return true; @@ -226,10 +246,7 @@ 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()); } @@ -318,7 +335,7 @@ 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 (isByVal || AllCallersPassInValidPointerForArgument(Arg)) SafeToUnconditionallyLoad.insert(IndicesVector(1, 0)); // First, iterate the entry block and mark loads of (geps of) arguments as @@ -363,7 +380,8 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { User *U = *UI; Operands.clear(); if (LoadInst *LI = dyn_cast(U)) { - if (LI->isVolatile()) return false; // Don't hack volatile loads + // 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); @@ -391,7 +409,8 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { 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 + // Don't hack volatile/atomic loads + if (!LI->isSimple()) return false; Loads.push_back(LI); } else { // Other uses than load? @@ -434,8 +453,6 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { 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 @@ -443,11 +460,8 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { 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)) + AliasAnalysis::Location Loc = AA.getLocation(Load); + if (AA.canInstructionRangeModify(BB->front(), *Load, Loc)) return false; // Pointer is invalidated! // Now check every path from the entry block to the load for transparency. @@ -458,7 +472,7 @@ bool ArgPromotion::isSafeToPromoteArgument(Argument *Arg, bool isByVal) const { 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)) + if (AA.canBasicBlockModify(**I, Loc)) return false; } } @@ -478,8 +492,8 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // 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; @@ -497,15 +511,17 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // what the new GEP/Load instructions we are inserting look like. std::map 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(); + const AttributeSet &PAL = F->getAttributes(); // Add any return attributes. - if (Attributes attrs = PAL.getRetAttributes()) - AttributesVec.push_back(AttributeWithIndex::get(0, attrs)); + Attribute attrs = PAL.getRetAttributes(); + if (attrs.hasAttributes()) + AttributesVec.push_back(AttributeWithIndex::get(AttributeSet::ReturnIndex, + attrs)); // First, determine the new argument list unsigned ArgIndex = 1; @@ -513,15 +529,16 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, ++I, ++ArgIndex) { 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); + Type *AgTy = cast(I->getType())->getElementType(); + StructType *STy = cast(AgTy); for (unsigned i = 0, e = STy->getNumElements(); i != e; ++i) Params.push_back(STy->getElementType(i)); ++NumByValArgsPromoted; } else if (!ArgsToPromote.count(I)) { // Unchanged argument Params.push_back(I->getType()); - if (Attributes attrs = PAL.getParamAttributes(ArgIndex)) + Attribute attrs = PAL.getParamAttributes(ArgIndex); + if (attrs.hasAttributes()) AttributesVec.push_back(AttributeWithIndex::get(Params.size(), attrs)); } else if (I->use_empty()) { // Dead argument (which are always marked as promotable) @@ -562,9 +579,7 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, 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(I->getType(), *SI)); assert(Params.back()); } @@ -576,18 +591,12 @@ 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(); + attrs = PAL.getFnAttributes(); + if (attrs.hasAttributes()) + AttributesVec.push_back(AttributeWithIndex::get(AttributeSet::FunctionIndex, + attrs)); - // 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()); @@ -602,8 +611,7 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *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); @@ -628,11 +636,13 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, CallSite CS(F->use_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)); + Attribute attrs = CallPAL.getRetAttributes(); + if (attrs.hasAttributes()) + AttributesVec.push_back(AttributeWithIndex::get(AttributeSet::ReturnIndex, + attrs)); // Loop over the operands, inserting GEP and loads in the caller as // appropriate. @@ -643,18 +653,19 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, if (!ArgsToPromote.count(I) && !ByValArgsToTransform.count(I)) { Args.push_back(*AI); // Unmodified argument - if (Attributes Attrs = CallPAL.getParamAttributes(ArgIndex)) + Attribute Attrs = CallPAL.getParamAttributes(ArgIndex); + if (Attrs.hasAttributes()) AttributesVec.push_back(AttributeWithIndex::get(Args.size(), Attrs)); } 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 }; 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, + Value *Idx = GetElementPtrInst::Create(*AI, Idxs, (*AI)->getName()+"."+utostr(i), Call); // TODO: Tell AA about the new values? @@ -672,12 +683,12 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, LoadInst *OrigLoad = OriginalLoads[*SI]; if (!SI->empty()) { Ops.reserve(SI->size()); - const Type *ElTy = V->getType(); + Type *ElTy = V->getType(); for (IndicesVector::const_iterator II = SI->begin(), IE = SI->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)); @@ -685,8 +696,7 @@ 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(V, Ops, V->getName()+".idx", Call); Ops.clear(); AA.copyValue(OrigLoad->getOperand(0), V); } @@ -694,37 +704,40 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, // of the previous load. LoadInst *newLoad = new LoadInst(V, V->getName()+".val", Call); newLoad->setAlignment(OrigLoad->getAlignment()); + // Transfer the TBAA info too. + newLoad->setMetadata(LLVMContext::MD_tbaa, + OrigLoad->getMetadata(LLVMContext::MD_tbaa)); 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)) + Attribute Attrs = CallPAL.getParamAttributes(ArgIndex); + if (Attrs.hasAttributes()) AttributesVec.push_back(AttributeWithIndex::get(Args.size(), Attrs)); } // Add any function attributes. - if (Attributes attrs = CallPAL.getFnAttributes()) - AttributesVec.push_back(AttributeWithIndex::get(~0, attrs)); + attrs = CallPAL.getFnAttributes(); + if (attrs.hasAttributes()) + AttributesVec.push_back(AttributeWithIndex::get(AttributeSet::FunctionIndex, + attrs)); 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(); } @@ -754,8 +767,8 @@ 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) { @@ -775,16 +788,16 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, Instruction *InsertPt = NF->begin()->begin(); // Just add all the struct element types. - const Type *AgTy = cast(I->getType())->getElementType(); + Type *AgTy = cast(I->getType())->getElementType(); Value *TheAlloca = new AllocaInst(AgTy, 0, "", InsertPt); - const StructType *STy = cast(AgTy); + StructType *STy = cast(AgTy); Value *Idxs[2] = { ConstantInt::get(Type::getInt32Ty(F->getContext()), 0), 0 }; 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, + GetElementPtrInst::Create(TheAlloca, Idxs, TheAlloca->getName()+"."+Twine(i), InsertPt); I2->setName(I->getName()+"."+Twine(i)); @@ -860,16 +873,9 @@ CallGraphNode *ArgPromotion::DoPromotion(Function *F, } // 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);