HexagonCommonGEP.cpp revision 296417
1286425Sdim//===--- HexagonCommonGEP.cpp ---------------------------------------------===// 2286425Sdim// 3286425Sdim// The LLVM Compiler Infrastructure 4286425Sdim// 5286425Sdim// This file is distributed under the University of Illinois Open Source 6286425Sdim// License. See LICENSE.TXT for details. 7286425Sdim// 8286425Sdim//===----------------------------------------------------------------------===// 9286425Sdim 10286425Sdim#define DEBUG_TYPE "commgep" 11286425Sdim 12286425Sdim#include "llvm/Pass.h" 13286425Sdim#include "llvm/ADT/FoldingSet.h" 14286425Sdim#include "llvm/ADT/STLExtras.h" 15286425Sdim#include "llvm/Analysis/LoopInfo.h" 16286425Sdim#include "llvm/Analysis/PostDominators.h" 17286425Sdim#include "llvm/CodeGen/MachineFunctionAnalysis.h" 18286425Sdim#include "llvm/IR/Constants.h" 19286425Sdim#include "llvm/IR/Dominators.h" 20286425Sdim#include "llvm/IR/Function.h" 21286425Sdim#include "llvm/IR/Instructions.h" 22286425Sdim#include "llvm/IR/Verifier.h" 23286425Sdim#include "llvm/Support/Allocator.h" 24286425Sdim#include "llvm/Support/CommandLine.h" 25286425Sdim#include "llvm/Support/Debug.h" 26286425Sdim#include "llvm/Support/raw_ostream.h" 27286425Sdim#include "llvm/Transforms/Scalar.h" 28286425Sdim#include "llvm/Transforms/Utils/Local.h" 29286425Sdim 30286425Sdim#include <map> 31286425Sdim#include <set> 32286425Sdim#include <vector> 33286425Sdim 34286425Sdim#include "HexagonTargetMachine.h" 35286425Sdim 36286425Sdimusing namespace llvm; 37286425Sdim 38286425Sdimstatic cl::opt<bool> OptSpeculate("commgep-speculate", cl::init(true), 39286425Sdim cl::Hidden, cl::ZeroOrMore); 40286425Sdim 41286425Sdimstatic cl::opt<bool> OptEnableInv("commgep-inv", cl::init(true), cl::Hidden, 42286425Sdim cl::ZeroOrMore); 43286425Sdim 44286425Sdimstatic cl::opt<bool> OptEnableConst("commgep-const", cl::init(true), 45286425Sdim cl::Hidden, cl::ZeroOrMore); 46286425Sdim 47286425Sdimnamespace llvm { 48286425Sdim void initializeHexagonCommonGEPPass(PassRegistry&); 49286425Sdim} 50286425Sdim 51286425Sdimnamespace { 52286425Sdim struct GepNode; 53286425Sdim typedef std::set<GepNode*> NodeSet; 54286425Sdim typedef std::map<GepNode*,Value*> NodeToValueMap; 55286425Sdim typedef std::vector<GepNode*> NodeVect; 56286425Sdim typedef std::map<GepNode*,NodeVect> NodeChildrenMap; 57286425Sdim typedef std::set<Use*> UseSet; 58286425Sdim typedef std::map<GepNode*,UseSet> NodeToUsesMap; 59286425Sdim 60286425Sdim // Numbering map for gep nodes. Used to keep track of ordering for 61286425Sdim // gep nodes. 62296417Sdim struct NodeOrdering { 63296417Sdim NodeOrdering() : LastNum(0) {} 64286425Sdim 65296417Sdim void insert(const GepNode *N) { Map.insert(std::make_pair(N, ++LastNum)); } 66296417Sdim void clear() { Map.clear(); } 67296417Sdim 68296417Sdim bool operator()(const GepNode *N1, const GepNode *N2) const { 69296417Sdim auto F1 = Map.find(N1), F2 = Map.find(N2); 70296417Sdim assert(F1 != Map.end() && F2 != Map.end()); 71286425Sdim return F1->second < F2->second; 72286425Sdim } 73296417Sdim 74286425Sdim private: 75296417Sdim std::map<const GepNode *, unsigned> Map; 76286425Sdim unsigned LastNum; 77286425Sdim }; 78286425Sdim 79286425Sdim class HexagonCommonGEP : public FunctionPass { 80286425Sdim public: 81286425Sdim static char ID; 82286425Sdim HexagonCommonGEP() : FunctionPass(ID) { 83286425Sdim initializeHexagonCommonGEPPass(*PassRegistry::getPassRegistry()); 84286425Sdim } 85286425Sdim virtual bool runOnFunction(Function &F); 86286425Sdim virtual const char *getPassName() const { 87286425Sdim return "Hexagon Common GEP"; 88286425Sdim } 89286425Sdim 90286425Sdim virtual void getAnalysisUsage(AnalysisUsage &AU) const { 91286425Sdim AU.addRequired<DominatorTreeWrapperPass>(); 92286425Sdim AU.addPreserved<DominatorTreeWrapperPass>(); 93286425Sdim AU.addRequired<PostDominatorTree>(); 94286425Sdim AU.addPreserved<PostDominatorTree>(); 95286425Sdim AU.addRequired<LoopInfoWrapperPass>(); 96286425Sdim AU.addPreserved<LoopInfoWrapperPass>(); 97286425Sdim FunctionPass::getAnalysisUsage(AU); 98286425Sdim } 99286425Sdim 100286425Sdim private: 101286425Sdim typedef std::map<Value*,GepNode*> ValueToNodeMap; 102286425Sdim typedef std::vector<Value*> ValueVect; 103286425Sdim typedef std::map<GepNode*,ValueVect> NodeToValuesMap; 104286425Sdim 105286425Sdim void getBlockTraversalOrder(BasicBlock *Root, ValueVect &Order); 106286425Sdim bool isHandledGepForm(GetElementPtrInst *GepI); 107286425Sdim void processGepInst(GetElementPtrInst *GepI, ValueToNodeMap &NM); 108286425Sdim void collect(); 109286425Sdim void common(); 110286425Sdim 111286425Sdim BasicBlock *recalculatePlacement(GepNode *Node, NodeChildrenMap &NCM, 112286425Sdim NodeToValueMap &Loc); 113286425Sdim BasicBlock *recalculatePlacementRec(GepNode *Node, NodeChildrenMap &NCM, 114286425Sdim NodeToValueMap &Loc); 115286425Sdim bool isInvariantIn(Value *Val, Loop *L); 116286425Sdim bool isInvariantIn(GepNode *Node, Loop *L); 117286425Sdim bool isInMainPath(BasicBlock *B, Loop *L); 118286425Sdim BasicBlock *adjustForInvariance(GepNode *Node, NodeChildrenMap &NCM, 119286425Sdim NodeToValueMap &Loc); 120286425Sdim void separateChainForNode(GepNode *Node, Use *U, NodeToValueMap &Loc); 121286425Sdim void separateConstantChains(GepNode *Node, NodeChildrenMap &NCM, 122286425Sdim NodeToValueMap &Loc); 123286425Sdim void computeNodePlacement(NodeToValueMap &Loc); 124286425Sdim 125286425Sdim Value *fabricateGEP(NodeVect &NA, BasicBlock::iterator At, 126286425Sdim BasicBlock *LocB); 127286425Sdim void getAllUsersForNode(GepNode *Node, ValueVect &Values, 128286425Sdim NodeChildrenMap &NCM); 129286425Sdim void materialize(NodeToValueMap &Loc); 130286425Sdim 131286425Sdim void removeDeadCode(); 132286425Sdim 133286425Sdim NodeVect Nodes; 134286425Sdim NodeToUsesMap Uses; 135286425Sdim NodeOrdering NodeOrder; // Node ordering, for deterministic behavior. 136286425Sdim SpecificBumpPtrAllocator<GepNode> *Mem; 137286425Sdim LLVMContext *Ctx; 138286425Sdim LoopInfo *LI; 139286425Sdim DominatorTree *DT; 140286425Sdim PostDominatorTree *PDT; 141286425Sdim Function *Fn; 142286425Sdim }; 143286425Sdim} 144286425Sdim 145286425Sdim 146286425Sdimchar HexagonCommonGEP::ID = 0; 147286425SdimINITIALIZE_PASS_BEGIN(HexagonCommonGEP, "hcommgep", "Hexagon Common GEP", 148286425Sdim false, false) 149286425SdimINITIALIZE_PASS_DEPENDENCY(DominatorTreeWrapperPass) 150286425SdimINITIALIZE_PASS_DEPENDENCY(PostDominatorTree) 151286425SdimINITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass) 152286425SdimINITIALIZE_PASS_END(HexagonCommonGEP, "hcommgep", "Hexagon Common GEP", 153286425Sdim false, false) 154286425Sdim 155286425Sdimnamespace { 156286425Sdim struct GepNode { 157286425Sdim enum { 158286425Sdim None = 0, 159286425Sdim Root = 0x01, 160286425Sdim Internal = 0x02, 161286425Sdim Used = 0x04 162286425Sdim }; 163286425Sdim 164286425Sdim uint32_t Flags; 165286425Sdim union { 166286425Sdim GepNode *Parent; 167286425Sdim Value *BaseVal; 168286425Sdim }; 169286425Sdim Value *Idx; 170286425Sdim Type *PTy; // Type of the pointer operand. 171286425Sdim 172286425Sdim GepNode() : Flags(0), Parent(0), Idx(0), PTy(0) {} 173286425Sdim GepNode(const GepNode *N) : Flags(N->Flags), Idx(N->Idx), PTy(N->PTy) { 174286425Sdim if (Flags & Root) 175286425Sdim BaseVal = N->BaseVal; 176286425Sdim else 177286425Sdim Parent = N->Parent; 178286425Sdim } 179286425Sdim friend raw_ostream &operator<< (raw_ostream &OS, const GepNode &GN); 180286425Sdim }; 181286425Sdim 182286425Sdim 183286425Sdim Type *next_type(Type *Ty, Value *Idx) { 184286425Sdim // Advance the type. 185286425Sdim if (!Ty->isStructTy()) { 186286425Sdim Type *NexTy = cast<SequentialType>(Ty)->getElementType(); 187286425Sdim return NexTy; 188286425Sdim } 189286425Sdim // Otherwise it is a struct type. 190286425Sdim ConstantInt *CI = dyn_cast<ConstantInt>(Idx); 191286425Sdim assert(CI && "Struct type with non-constant index"); 192286425Sdim int64_t i = CI->getValue().getSExtValue(); 193286425Sdim Type *NextTy = cast<StructType>(Ty)->getElementType(i); 194286425Sdim return NextTy; 195286425Sdim } 196286425Sdim 197286425Sdim 198286425Sdim raw_ostream &operator<< (raw_ostream &OS, const GepNode &GN) { 199286425Sdim OS << "{ {"; 200286425Sdim bool Comma = false; 201286425Sdim if (GN.Flags & GepNode::Root) { 202286425Sdim OS << "root"; 203286425Sdim Comma = true; 204286425Sdim } 205286425Sdim if (GN.Flags & GepNode::Internal) { 206286425Sdim if (Comma) 207286425Sdim OS << ','; 208286425Sdim OS << "internal"; 209286425Sdim Comma = true; 210286425Sdim } 211286425Sdim if (GN.Flags & GepNode::Used) { 212286425Sdim if (Comma) 213286425Sdim OS << ','; 214286425Sdim OS << "used"; 215286425Sdim Comma = true; 216286425Sdim } 217286425Sdim OS << "} "; 218286425Sdim if (GN.Flags & GepNode::Root) 219286425Sdim OS << "BaseVal:" << GN.BaseVal->getName() << '(' << GN.BaseVal << ')'; 220286425Sdim else 221286425Sdim OS << "Parent:" << GN.Parent; 222286425Sdim 223286425Sdim OS << " Idx:"; 224286425Sdim if (ConstantInt *CI = dyn_cast<ConstantInt>(GN.Idx)) 225286425Sdim OS << CI->getValue().getSExtValue(); 226286425Sdim else if (GN.Idx->hasName()) 227286425Sdim OS << GN.Idx->getName(); 228286425Sdim else 229286425Sdim OS << "<anon> =" << *GN.Idx; 230286425Sdim 231286425Sdim OS << " PTy:"; 232286425Sdim if (GN.PTy->isStructTy()) { 233286425Sdim StructType *STy = cast<StructType>(GN.PTy); 234286425Sdim if (!STy->isLiteral()) 235286425Sdim OS << GN.PTy->getStructName(); 236286425Sdim else 237286425Sdim OS << "<anon-struct>:" << *STy; 238286425Sdim } 239286425Sdim else 240286425Sdim OS << *GN.PTy; 241286425Sdim OS << " }"; 242286425Sdim return OS; 243286425Sdim } 244286425Sdim 245286425Sdim 246286425Sdim template <typename NodeContainer> 247286425Sdim void dump_node_container(raw_ostream &OS, const NodeContainer &S) { 248286425Sdim typedef typename NodeContainer::const_iterator const_iterator; 249286425Sdim for (const_iterator I = S.begin(), E = S.end(); I != E; ++I) 250286425Sdim OS << *I << ' ' << **I << '\n'; 251286425Sdim } 252286425Sdim 253286425Sdim raw_ostream &operator<< (raw_ostream &OS, 254286425Sdim const NodeVect &S) LLVM_ATTRIBUTE_UNUSED; 255286425Sdim raw_ostream &operator<< (raw_ostream &OS, const NodeVect &S) { 256286425Sdim dump_node_container(OS, S); 257286425Sdim return OS; 258286425Sdim } 259286425Sdim 260286425Sdim 261286425Sdim raw_ostream &operator<< (raw_ostream &OS, 262286425Sdim const NodeToUsesMap &M) LLVM_ATTRIBUTE_UNUSED; 263286425Sdim raw_ostream &operator<< (raw_ostream &OS, const NodeToUsesMap &M){ 264286425Sdim typedef NodeToUsesMap::const_iterator const_iterator; 265286425Sdim for (const_iterator I = M.begin(), E = M.end(); I != E; ++I) { 266286425Sdim const UseSet &Us = I->second; 267286425Sdim OS << I->first << " -> #" << Us.size() << '{'; 268286425Sdim for (UseSet::const_iterator J = Us.begin(), F = Us.end(); J != F; ++J) { 269286425Sdim User *R = (*J)->getUser(); 270286425Sdim if (R->hasName()) 271286425Sdim OS << ' ' << R->getName(); 272286425Sdim else 273286425Sdim OS << " <?>(" << *R << ')'; 274286425Sdim } 275286425Sdim OS << " }\n"; 276286425Sdim } 277286425Sdim return OS; 278286425Sdim } 279286425Sdim 280286425Sdim 281286425Sdim struct in_set { 282286425Sdim in_set(const NodeSet &S) : NS(S) {} 283286425Sdim bool operator() (GepNode *N) const { 284286425Sdim return NS.find(N) != NS.end(); 285286425Sdim } 286286425Sdim private: 287286425Sdim const NodeSet &NS; 288286425Sdim }; 289286425Sdim} 290286425Sdim 291286425Sdim 292286425Sdiminline void *operator new(size_t, SpecificBumpPtrAllocator<GepNode> &A) { 293286425Sdim return A.Allocate(); 294286425Sdim} 295286425Sdim 296286425Sdim 297286425Sdimvoid HexagonCommonGEP::getBlockTraversalOrder(BasicBlock *Root, 298286425Sdim ValueVect &Order) { 299286425Sdim // Compute block ordering for a typical DT-based traversal of the flow 300286425Sdim // graph: "before visiting a block, all of its dominators must have been 301286425Sdim // visited". 302286425Sdim 303286425Sdim Order.push_back(Root); 304286425Sdim DomTreeNode *DTN = DT->getNode(Root); 305286425Sdim typedef GraphTraits<DomTreeNode*> GTN; 306286425Sdim typedef GTN::ChildIteratorType Iter; 307286425Sdim for (Iter I = GTN::child_begin(DTN), E = GTN::child_end(DTN); I != E; ++I) 308286425Sdim getBlockTraversalOrder((*I)->getBlock(), Order); 309286425Sdim} 310286425Sdim 311286425Sdim 312286425Sdimbool HexagonCommonGEP::isHandledGepForm(GetElementPtrInst *GepI) { 313286425Sdim // No vector GEPs. 314286425Sdim if (!GepI->getType()->isPointerTy()) 315286425Sdim return false; 316286425Sdim // No GEPs without any indices. (Is this possible?) 317286425Sdim if (GepI->idx_begin() == GepI->idx_end()) 318286425Sdim return false; 319286425Sdim return true; 320286425Sdim} 321286425Sdim 322286425Sdim 323286425Sdimvoid HexagonCommonGEP::processGepInst(GetElementPtrInst *GepI, 324286425Sdim ValueToNodeMap &NM) { 325286425Sdim DEBUG(dbgs() << "Visiting GEP: " << *GepI << '\n'); 326286425Sdim GepNode *N = new (*Mem) GepNode; 327286425Sdim Value *PtrOp = GepI->getPointerOperand(); 328286425Sdim ValueToNodeMap::iterator F = NM.find(PtrOp); 329286425Sdim if (F == NM.end()) { 330286425Sdim N->BaseVal = PtrOp; 331286425Sdim N->Flags |= GepNode::Root; 332286425Sdim } else { 333286425Sdim // If PtrOp was a GEP instruction, it must have already been processed. 334286425Sdim // The ValueToNodeMap entry for it is the last gep node in the generated 335286425Sdim // chain. Link to it here. 336286425Sdim N->Parent = F->second; 337286425Sdim } 338286425Sdim N->PTy = PtrOp->getType(); 339286425Sdim N->Idx = *GepI->idx_begin(); 340286425Sdim 341286425Sdim // Collect the list of users of this GEP instruction. Will add it to the 342286425Sdim // last node created for it. 343286425Sdim UseSet Us; 344286425Sdim for (Value::user_iterator UI = GepI->user_begin(), UE = GepI->user_end(); 345286425Sdim UI != UE; ++UI) { 346286425Sdim // Check if this gep is used by anything other than other geps that 347286425Sdim // we will process. 348286425Sdim if (isa<GetElementPtrInst>(*UI)) { 349286425Sdim GetElementPtrInst *UserG = cast<GetElementPtrInst>(*UI); 350286425Sdim if (isHandledGepForm(UserG)) 351286425Sdim continue; 352286425Sdim } 353286425Sdim Us.insert(&UI.getUse()); 354286425Sdim } 355286425Sdim Nodes.push_back(N); 356286425Sdim NodeOrder.insert(N); 357286425Sdim 358286425Sdim // Skip the first index operand, since we only handle 0. This dereferences 359286425Sdim // the pointer operand. 360286425Sdim GepNode *PN = N; 361286425Sdim Type *PtrTy = cast<PointerType>(PtrOp->getType())->getElementType(); 362286425Sdim for (User::op_iterator OI = GepI->idx_begin()+1, OE = GepI->idx_end(); 363286425Sdim OI != OE; ++OI) { 364286425Sdim Value *Op = *OI; 365286425Sdim GepNode *Nx = new (*Mem) GepNode; 366286425Sdim Nx->Parent = PN; // Link Nx to the previous node. 367286425Sdim Nx->Flags |= GepNode::Internal; 368286425Sdim Nx->PTy = PtrTy; 369286425Sdim Nx->Idx = Op; 370286425Sdim Nodes.push_back(Nx); 371286425Sdim NodeOrder.insert(Nx); 372286425Sdim PN = Nx; 373286425Sdim 374286425Sdim PtrTy = next_type(PtrTy, Op); 375286425Sdim } 376286425Sdim 377286425Sdim // After last node has been created, update the use information. 378286425Sdim if (!Us.empty()) { 379286425Sdim PN->Flags |= GepNode::Used; 380286425Sdim Uses[PN].insert(Us.begin(), Us.end()); 381286425Sdim } 382286425Sdim 383286425Sdim // Link the last node with the originating GEP instruction. This is to 384286425Sdim // help with linking chained GEP instructions. 385286425Sdim NM.insert(std::make_pair(GepI, PN)); 386286425Sdim} 387286425Sdim 388286425Sdim 389286425Sdimvoid HexagonCommonGEP::collect() { 390286425Sdim // Establish depth-first traversal order of the dominator tree. 391286425Sdim ValueVect BO; 392296417Sdim getBlockTraversalOrder(&Fn->front(), BO); 393286425Sdim 394286425Sdim // The creation of gep nodes requires DT-traversal. When processing a GEP 395286425Sdim // instruction that uses another GEP instruction as the base pointer, the 396286425Sdim // gep node for the base pointer should already exist. 397286425Sdim ValueToNodeMap NM; 398286425Sdim for (ValueVect::iterator I = BO.begin(), E = BO.end(); I != E; ++I) { 399286425Sdim BasicBlock *B = cast<BasicBlock>(*I); 400286425Sdim for (BasicBlock::iterator J = B->begin(), F = B->end(); J != F; ++J) { 401286425Sdim if (!isa<GetElementPtrInst>(J)) 402286425Sdim continue; 403286425Sdim GetElementPtrInst *GepI = cast<GetElementPtrInst>(J); 404286425Sdim if (isHandledGepForm(GepI)) 405286425Sdim processGepInst(GepI, NM); 406286425Sdim } 407286425Sdim } 408286425Sdim 409286425Sdim DEBUG(dbgs() << "Gep nodes after initial collection:\n" << Nodes); 410286425Sdim} 411286425Sdim 412286425Sdim 413286425Sdimnamespace { 414286425Sdim void invert_find_roots(const NodeVect &Nodes, NodeChildrenMap &NCM, 415286425Sdim NodeVect &Roots) { 416286425Sdim typedef NodeVect::const_iterator const_iterator; 417286425Sdim for (const_iterator I = Nodes.begin(), E = Nodes.end(); I != E; ++I) { 418286425Sdim GepNode *N = *I; 419286425Sdim if (N->Flags & GepNode::Root) { 420286425Sdim Roots.push_back(N); 421286425Sdim continue; 422286425Sdim } 423286425Sdim GepNode *PN = N->Parent; 424286425Sdim NCM[PN].push_back(N); 425286425Sdim } 426286425Sdim } 427286425Sdim 428286425Sdim void nodes_for_root(GepNode *Root, NodeChildrenMap &NCM, NodeSet &Nodes) { 429286425Sdim NodeVect Work; 430286425Sdim Work.push_back(Root); 431286425Sdim Nodes.insert(Root); 432286425Sdim 433286425Sdim while (!Work.empty()) { 434286425Sdim NodeVect::iterator First = Work.begin(); 435286425Sdim GepNode *N = *First; 436286425Sdim Work.erase(First); 437286425Sdim NodeChildrenMap::iterator CF = NCM.find(N); 438286425Sdim if (CF != NCM.end()) { 439286425Sdim Work.insert(Work.end(), CF->second.begin(), CF->second.end()); 440286425Sdim Nodes.insert(CF->second.begin(), CF->second.end()); 441286425Sdim } 442286425Sdim } 443286425Sdim } 444286425Sdim} 445286425Sdim 446286425Sdim 447286425Sdimnamespace { 448286425Sdim typedef std::set<NodeSet> NodeSymRel; 449286425Sdim typedef std::pair<GepNode*,GepNode*> NodePair; 450286425Sdim typedef std::set<NodePair> NodePairSet; 451286425Sdim 452286425Sdim const NodeSet *node_class(GepNode *N, NodeSymRel &Rel) { 453286425Sdim for (NodeSymRel::iterator I = Rel.begin(), E = Rel.end(); I != E; ++I) 454286425Sdim if (I->count(N)) 455286425Sdim return &*I; 456286425Sdim return 0; 457286425Sdim } 458286425Sdim 459286425Sdim // Create an ordered pair of GepNode pointers. The pair will be used in 460286425Sdim // determining equality. The only purpose of the ordering is to eliminate 461286425Sdim // duplication due to the commutativity of equality/non-equality. 462286425Sdim NodePair node_pair(GepNode *N1, GepNode *N2) { 463286425Sdim uintptr_t P1 = uintptr_t(N1), P2 = uintptr_t(N2); 464286425Sdim if (P1 <= P2) 465286425Sdim return std::make_pair(N1, N2); 466286425Sdim return std::make_pair(N2, N1); 467286425Sdim } 468286425Sdim 469286425Sdim unsigned node_hash(GepNode *N) { 470286425Sdim // Include everything except flags and parent. 471286425Sdim FoldingSetNodeID ID; 472286425Sdim ID.AddPointer(N->Idx); 473286425Sdim ID.AddPointer(N->PTy); 474286425Sdim return ID.ComputeHash(); 475286425Sdim } 476286425Sdim 477286425Sdim bool node_eq(GepNode *N1, GepNode *N2, NodePairSet &Eq, NodePairSet &Ne) { 478286425Sdim // Don't cache the result for nodes with different hashes. The hash 479286425Sdim // comparison is fast enough. 480286425Sdim if (node_hash(N1) != node_hash(N2)) 481286425Sdim return false; 482286425Sdim 483286425Sdim NodePair NP = node_pair(N1, N2); 484286425Sdim NodePairSet::iterator FEq = Eq.find(NP); 485286425Sdim if (FEq != Eq.end()) 486286425Sdim return true; 487286425Sdim NodePairSet::iterator FNe = Ne.find(NP); 488286425Sdim if (FNe != Ne.end()) 489286425Sdim return false; 490286425Sdim // Not previously compared. 491286425Sdim bool Root1 = N1->Flags & GepNode::Root; 492286425Sdim bool Root2 = N2->Flags & GepNode::Root; 493286425Sdim NodePair P = node_pair(N1, N2); 494286425Sdim // If the Root flag has different values, the nodes are different. 495286425Sdim // If both nodes are root nodes, but their base pointers differ, 496286425Sdim // they are different. 497286425Sdim if (Root1 != Root2 || (Root1 && N1->BaseVal != N2->BaseVal)) { 498286425Sdim Ne.insert(P); 499286425Sdim return false; 500286425Sdim } 501286425Sdim // Here the root flags are identical, and for root nodes the 502286425Sdim // base pointers are equal, so the root nodes are equal. 503286425Sdim // For non-root nodes, compare their parent nodes. 504286425Sdim if (Root1 || node_eq(N1->Parent, N2->Parent, Eq, Ne)) { 505286425Sdim Eq.insert(P); 506286425Sdim return true; 507286425Sdim } 508286425Sdim return false; 509286425Sdim } 510286425Sdim} 511286425Sdim 512286425Sdim 513286425Sdimvoid HexagonCommonGEP::common() { 514286425Sdim // The essence of this commoning is finding gep nodes that are equal. 515286425Sdim // To do this we need to compare all pairs of nodes. To save time, 516286425Sdim // first, partition the set of all nodes into sets of potentially equal 517286425Sdim // nodes, and then compare pairs from within each partition. 518286425Sdim typedef std::map<unsigned,NodeSet> NodeSetMap; 519286425Sdim NodeSetMap MaybeEq; 520286425Sdim 521286425Sdim for (NodeVect::iterator I = Nodes.begin(), E = Nodes.end(); I != E; ++I) { 522286425Sdim GepNode *N = *I; 523286425Sdim unsigned H = node_hash(N); 524286425Sdim MaybeEq[H].insert(N); 525286425Sdim } 526286425Sdim 527286425Sdim // Compute the equivalence relation for the gep nodes. Use two caches, 528286425Sdim // one for equality and the other for non-equality. 529286425Sdim NodeSymRel EqRel; // Equality relation (as set of equivalence classes). 530286425Sdim NodePairSet Eq, Ne; // Caches. 531286425Sdim for (NodeSetMap::iterator I = MaybeEq.begin(), E = MaybeEq.end(); 532286425Sdim I != E; ++I) { 533286425Sdim NodeSet &S = I->second; 534286425Sdim for (NodeSet::iterator NI = S.begin(), NE = S.end(); NI != NE; ++NI) { 535286425Sdim GepNode *N = *NI; 536286425Sdim // If node already has a class, then the class must have been created 537286425Sdim // in a prior iteration of this loop. Since equality is transitive, 538286425Sdim // nothing more will be added to that class, so skip it. 539286425Sdim if (node_class(N, EqRel)) 540286425Sdim continue; 541286425Sdim 542286425Sdim // Create a new class candidate now. 543286425Sdim NodeSet C; 544286425Sdim for (NodeSet::iterator NJ = std::next(NI); NJ != NE; ++NJ) 545286425Sdim if (node_eq(N, *NJ, Eq, Ne)) 546286425Sdim C.insert(*NJ); 547286425Sdim // If Tmp is empty, N would be the only element in it. Don't bother 548286425Sdim // creating a class for it then. 549286425Sdim if (!C.empty()) { 550286425Sdim C.insert(N); // Finalize the set before adding it to the relation. 551286425Sdim std::pair<NodeSymRel::iterator, bool> Ins = EqRel.insert(C); 552286425Sdim (void)Ins; 553286425Sdim assert(Ins.second && "Cannot add a class"); 554286425Sdim } 555286425Sdim } 556286425Sdim } 557286425Sdim 558286425Sdim DEBUG({ 559286425Sdim dbgs() << "Gep node equality:\n"; 560286425Sdim for (NodePairSet::iterator I = Eq.begin(), E = Eq.end(); I != E; ++I) 561286425Sdim dbgs() << "{ " << I->first << ", " << I->second << " }\n"; 562286425Sdim 563286425Sdim dbgs() << "Gep equivalence classes:\n"; 564286425Sdim for (NodeSymRel::iterator I = EqRel.begin(), E = EqRel.end(); I != E; ++I) { 565286425Sdim dbgs() << '{'; 566286425Sdim const NodeSet &S = *I; 567286425Sdim for (NodeSet::const_iterator J = S.begin(), F = S.end(); J != F; ++J) { 568286425Sdim if (J != S.begin()) 569286425Sdim dbgs() << ','; 570286425Sdim dbgs() << ' ' << *J; 571286425Sdim } 572286425Sdim dbgs() << " }\n"; 573286425Sdim } 574286425Sdim }); 575286425Sdim 576286425Sdim 577286425Sdim // Create a projection from a NodeSet to the minimal element in it. 578286425Sdim typedef std::map<const NodeSet*,GepNode*> ProjMap; 579286425Sdim ProjMap PM; 580286425Sdim for (NodeSymRel::iterator I = EqRel.begin(), E = EqRel.end(); I != E; ++I) { 581286425Sdim const NodeSet &S = *I; 582286425Sdim GepNode *Min = *std::min_element(S.begin(), S.end(), NodeOrder); 583286425Sdim std::pair<ProjMap::iterator,bool> Ins = PM.insert(std::make_pair(&S, Min)); 584286425Sdim (void)Ins; 585286425Sdim assert(Ins.second && "Cannot add minimal element"); 586286425Sdim 587286425Sdim // Update the min element's flags, and user list. 588286425Sdim uint32_t Flags = 0; 589286425Sdim UseSet &MinUs = Uses[Min]; 590286425Sdim for (NodeSet::iterator J = S.begin(), F = S.end(); J != F; ++J) { 591286425Sdim GepNode *N = *J; 592286425Sdim uint32_t NF = N->Flags; 593286425Sdim // If N is used, append all original values of N to the list of 594286425Sdim // original values of Min. 595286425Sdim if (NF & GepNode::Used) 596286425Sdim MinUs.insert(Uses[N].begin(), Uses[N].end()); 597286425Sdim Flags |= NF; 598286425Sdim } 599286425Sdim if (MinUs.empty()) 600286425Sdim Uses.erase(Min); 601286425Sdim 602286425Sdim // The collected flags should include all the flags from the min element. 603286425Sdim assert((Min->Flags & Flags) == Min->Flags); 604286425Sdim Min->Flags = Flags; 605286425Sdim } 606286425Sdim 607286425Sdim // Commoning: for each non-root gep node, replace "Parent" with the 608286425Sdim // selected (minimum) node from the corresponding equivalence class. 609286425Sdim // If a given parent does not have an equivalence class, leave it 610286425Sdim // unchanged (it means that it's the only element in its class). 611286425Sdim for (NodeVect::iterator I = Nodes.begin(), E = Nodes.end(); I != E; ++I) { 612286425Sdim GepNode *N = *I; 613286425Sdim if (N->Flags & GepNode::Root) 614286425Sdim continue; 615286425Sdim const NodeSet *PC = node_class(N->Parent, EqRel); 616286425Sdim if (!PC) 617286425Sdim continue; 618286425Sdim ProjMap::iterator F = PM.find(PC); 619286425Sdim if (F == PM.end()) 620286425Sdim continue; 621286425Sdim // Found a replacement, use it. 622286425Sdim GepNode *Rep = F->second; 623286425Sdim N->Parent = Rep; 624286425Sdim } 625286425Sdim 626286425Sdim DEBUG(dbgs() << "Gep nodes after commoning:\n" << Nodes); 627286425Sdim 628286425Sdim // Finally, erase the nodes that are no longer used. 629286425Sdim NodeSet Erase; 630286425Sdim for (NodeVect::iterator I = Nodes.begin(), E = Nodes.end(); I != E; ++I) { 631286425Sdim GepNode *N = *I; 632286425Sdim const NodeSet *PC = node_class(N, EqRel); 633286425Sdim if (!PC) 634286425Sdim continue; 635286425Sdim ProjMap::iterator F = PM.find(PC); 636286425Sdim if (F == PM.end()) 637286425Sdim continue; 638286425Sdim if (N == F->second) 639286425Sdim continue; 640286425Sdim // Node for removal. 641286425Sdim Erase.insert(*I); 642286425Sdim } 643286425Sdim NodeVect::iterator NewE = std::remove_if(Nodes.begin(), Nodes.end(), 644286425Sdim in_set(Erase)); 645286425Sdim Nodes.resize(std::distance(Nodes.begin(), NewE)); 646286425Sdim 647286425Sdim DEBUG(dbgs() << "Gep nodes after post-commoning cleanup:\n" << Nodes); 648286425Sdim} 649286425Sdim 650286425Sdim 651286425Sdimnamespace { 652286425Sdim template <typename T> 653286425Sdim BasicBlock *nearest_common_dominator(DominatorTree *DT, T &Blocks) { 654286425Sdim DEBUG({ 655286425Sdim dbgs() << "NCD of {"; 656286425Sdim for (typename T::iterator I = Blocks.begin(), E = Blocks.end(); 657286425Sdim I != E; ++I) { 658286425Sdim if (!*I) 659286425Sdim continue; 660286425Sdim BasicBlock *B = cast<BasicBlock>(*I); 661286425Sdim dbgs() << ' ' << B->getName(); 662286425Sdim } 663286425Sdim dbgs() << " }\n"; 664286425Sdim }); 665286425Sdim 666286425Sdim // Allow null basic blocks in Blocks. In such cases, return 0. 667286425Sdim typename T::iterator I = Blocks.begin(), E = Blocks.end(); 668286425Sdim if (I == E || !*I) 669286425Sdim return 0; 670286425Sdim BasicBlock *Dom = cast<BasicBlock>(*I); 671286425Sdim while (++I != E) { 672286425Sdim BasicBlock *B = cast_or_null<BasicBlock>(*I); 673286425Sdim Dom = B ? DT->findNearestCommonDominator(Dom, B) : 0; 674286425Sdim if (!Dom) 675286425Sdim return 0; 676286425Sdim } 677286425Sdim DEBUG(dbgs() << "computed:" << Dom->getName() << '\n'); 678286425Sdim return Dom; 679286425Sdim } 680286425Sdim 681286425Sdim template <typename T> 682286425Sdim BasicBlock *nearest_common_dominatee(DominatorTree *DT, T &Blocks) { 683286425Sdim // If two blocks, A and B, dominate a block C, then A dominates B, 684286425Sdim // or B dominates A. 685286425Sdim typename T::iterator I = Blocks.begin(), E = Blocks.end(); 686286425Sdim // Find the first non-null block. 687286425Sdim while (I != E && !*I) 688286425Sdim ++I; 689286425Sdim if (I == E) 690286425Sdim return DT->getRoot(); 691286425Sdim BasicBlock *DomB = cast<BasicBlock>(*I); 692286425Sdim while (++I != E) { 693286425Sdim if (!*I) 694286425Sdim continue; 695286425Sdim BasicBlock *B = cast<BasicBlock>(*I); 696286425Sdim if (DT->dominates(B, DomB)) 697286425Sdim continue; 698286425Sdim if (!DT->dominates(DomB, B)) 699286425Sdim return 0; 700286425Sdim DomB = B; 701286425Sdim } 702286425Sdim return DomB; 703286425Sdim } 704286425Sdim 705286425Sdim // Find the first use in B of any value from Values. If no such use, 706286425Sdim // return B->end(). 707286425Sdim template <typename T> 708286425Sdim BasicBlock::iterator first_use_of_in_block(T &Values, BasicBlock *B) { 709286425Sdim BasicBlock::iterator FirstUse = B->end(), BEnd = B->end(); 710286425Sdim typedef typename T::iterator iterator; 711286425Sdim for (iterator I = Values.begin(), E = Values.end(); I != E; ++I) { 712286425Sdim Value *V = *I; 713286425Sdim // If V is used in a PHI node, the use belongs to the incoming block, 714286425Sdim // not the block with the PHI node. In the incoming block, the use 715286425Sdim // would be considered as being at the end of it, so it cannot 716286425Sdim // influence the position of the first use (which is assumed to be 717286425Sdim // at the end to start with). 718286425Sdim if (isa<PHINode>(V)) 719286425Sdim continue; 720286425Sdim if (!isa<Instruction>(V)) 721286425Sdim continue; 722286425Sdim Instruction *In = cast<Instruction>(V); 723286425Sdim if (In->getParent() != B) 724286425Sdim continue; 725296417Sdim BasicBlock::iterator It = In->getIterator(); 726286425Sdim if (std::distance(FirstUse, BEnd) < std::distance(It, BEnd)) 727286425Sdim FirstUse = It; 728286425Sdim } 729286425Sdim return FirstUse; 730286425Sdim } 731286425Sdim 732286425Sdim bool is_empty(const BasicBlock *B) { 733286425Sdim return B->empty() || (&*B->begin() == B->getTerminator()); 734286425Sdim } 735286425Sdim} 736286425Sdim 737286425Sdim 738286425SdimBasicBlock *HexagonCommonGEP::recalculatePlacement(GepNode *Node, 739286425Sdim NodeChildrenMap &NCM, NodeToValueMap &Loc) { 740286425Sdim DEBUG(dbgs() << "Loc for node:" << Node << '\n'); 741286425Sdim // Recalculate the placement for Node, assuming that the locations of 742286425Sdim // its children in Loc are valid. 743286425Sdim // Return 0 if there is no valid placement for Node (for example, it 744286425Sdim // uses an index value that is not available at the location required 745286425Sdim // to dominate all children, etc.). 746286425Sdim 747286425Sdim // Find the nearest common dominator for: 748286425Sdim // - all users, if the node is used, and 749286425Sdim // - all children. 750286425Sdim ValueVect Bs; 751286425Sdim if (Node->Flags & GepNode::Used) { 752286425Sdim // Append all blocks with uses of the original values to the 753286425Sdim // block vector Bs. 754286425Sdim NodeToUsesMap::iterator UF = Uses.find(Node); 755286425Sdim assert(UF != Uses.end() && "Used node with no use information"); 756286425Sdim UseSet &Us = UF->second; 757286425Sdim for (UseSet::iterator I = Us.begin(), E = Us.end(); I != E; ++I) { 758286425Sdim Use *U = *I; 759286425Sdim User *R = U->getUser(); 760286425Sdim if (!isa<Instruction>(R)) 761286425Sdim continue; 762286425Sdim BasicBlock *PB = isa<PHINode>(R) 763286425Sdim ? cast<PHINode>(R)->getIncomingBlock(*U) 764286425Sdim : cast<Instruction>(R)->getParent(); 765286425Sdim Bs.push_back(PB); 766286425Sdim } 767286425Sdim } 768286425Sdim // Append the location of each child. 769286425Sdim NodeChildrenMap::iterator CF = NCM.find(Node); 770286425Sdim if (CF != NCM.end()) { 771286425Sdim NodeVect &Cs = CF->second; 772286425Sdim for (NodeVect::iterator I = Cs.begin(), E = Cs.end(); I != E; ++I) { 773286425Sdim GepNode *CN = *I; 774286425Sdim NodeToValueMap::iterator LF = Loc.find(CN); 775286425Sdim // If the child is only used in GEP instructions (i.e. is not used in 776286425Sdim // non-GEP instructions), the nearest dominator computed for it may 777286425Sdim // have been null. In such case it won't have a location available. 778286425Sdim if (LF == Loc.end()) 779286425Sdim continue; 780286425Sdim Bs.push_back(LF->second); 781286425Sdim } 782286425Sdim } 783286425Sdim 784286425Sdim BasicBlock *DomB = nearest_common_dominator(DT, Bs); 785286425Sdim if (!DomB) 786286425Sdim return 0; 787286425Sdim // Check if the index used by Node dominates the computed dominator. 788286425Sdim Instruction *IdxI = dyn_cast<Instruction>(Node->Idx); 789286425Sdim if (IdxI && !DT->dominates(IdxI->getParent(), DomB)) 790286425Sdim return 0; 791286425Sdim 792286425Sdim // Avoid putting nodes into empty blocks. 793286425Sdim while (is_empty(DomB)) { 794286425Sdim DomTreeNode *N = (*DT)[DomB]->getIDom(); 795286425Sdim if (!N) 796286425Sdim break; 797286425Sdim DomB = N->getBlock(); 798286425Sdim } 799286425Sdim 800286425Sdim // Otherwise, DomB is fine. Update the location map. 801286425Sdim Loc[Node] = DomB; 802286425Sdim return DomB; 803286425Sdim} 804286425Sdim 805286425Sdim 806286425SdimBasicBlock *HexagonCommonGEP::recalculatePlacementRec(GepNode *Node, 807286425Sdim NodeChildrenMap &NCM, NodeToValueMap &Loc) { 808286425Sdim DEBUG(dbgs() << "LocRec begin for node:" << Node << '\n'); 809286425Sdim // Recalculate the placement of Node, after recursively recalculating the 810286425Sdim // placements of all its children. 811286425Sdim NodeChildrenMap::iterator CF = NCM.find(Node); 812286425Sdim if (CF != NCM.end()) { 813286425Sdim NodeVect &Cs = CF->second; 814286425Sdim for (NodeVect::iterator I = Cs.begin(), E = Cs.end(); I != E; ++I) 815286425Sdim recalculatePlacementRec(*I, NCM, Loc); 816286425Sdim } 817286425Sdim BasicBlock *LB = recalculatePlacement(Node, NCM, Loc); 818286425Sdim DEBUG(dbgs() << "LocRec end for node:" << Node << '\n'); 819286425Sdim return LB; 820286425Sdim} 821286425Sdim 822286425Sdim 823286425Sdimbool HexagonCommonGEP::isInvariantIn(Value *Val, Loop *L) { 824286425Sdim if (isa<Constant>(Val) || isa<Argument>(Val)) 825286425Sdim return true; 826286425Sdim Instruction *In = dyn_cast<Instruction>(Val); 827286425Sdim if (!In) 828286425Sdim return false; 829286425Sdim BasicBlock *HdrB = L->getHeader(), *DefB = In->getParent(); 830286425Sdim return DT->properlyDominates(DefB, HdrB); 831286425Sdim} 832286425Sdim 833286425Sdim 834286425Sdimbool HexagonCommonGEP::isInvariantIn(GepNode *Node, Loop *L) { 835286425Sdim if (Node->Flags & GepNode::Root) 836286425Sdim if (!isInvariantIn(Node->BaseVal, L)) 837286425Sdim return false; 838286425Sdim return isInvariantIn(Node->Idx, L); 839286425Sdim} 840286425Sdim 841286425Sdim 842286425Sdimbool HexagonCommonGEP::isInMainPath(BasicBlock *B, Loop *L) { 843286425Sdim BasicBlock *HB = L->getHeader(); 844286425Sdim BasicBlock *LB = L->getLoopLatch(); 845286425Sdim // B must post-dominate the loop header or dominate the loop latch. 846286425Sdim if (PDT->dominates(B, HB)) 847286425Sdim return true; 848286425Sdim if (LB && DT->dominates(B, LB)) 849286425Sdim return true; 850286425Sdim return false; 851286425Sdim} 852286425Sdim 853286425Sdim 854286425Sdimnamespace { 855286425Sdim BasicBlock *preheader(DominatorTree *DT, Loop *L) { 856286425Sdim if (BasicBlock *PH = L->getLoopPreheader()) 857286425Sdim return PH; 858286425Sdim if (!OptSpeculate) 859286425Sdim return 0; 860286425Sdim DomTreeNode *DN = DT->getNode(L->getHeader()); 861286425Sdim if (!DN) 862286425Sdim return 0; 863286425Sdim return DN->getIDom()->getBlock(); 864286425Sdim } 865286425Sdim} 866286425Sdim 867286425Sdim 868286425SdimBasicBlock *HexagonCommonGEP::adjustForInvariance(GepNode *Node, 869286425Sdim NodeChildrenMap &NCM, NodeToValueMap &Loc) { 870286425Sdim // Find the "topmost" location for Node: it must be dominated by both, 871286425Sdim // its parent (or the BaseVal, if it's a root node), and by the index 872286425Sdim // value. 873286425Sdim ValueVect Bs; 874286425Sdim if (Node->Flags & GepNode::Root) { 875286425Sdim if (Instruction *PIn = dyn_cast<Instruction>(Node->BaseVal)) 876286425Sdim Bs.push_back(PIn->getParent()); 877286425Sdim } else { 878286425Sdim Bs.push_back(Loc[Node->Parent]); 879286425Sdim } 880286425Sdim if (Instruction *IIn = dyn_cast<Instruction>(Node->Idx)) 881286425Sdim Bs.push_back(IIn->getParent()); 882286425Sdim BasicBlock *TopB = nearest_common_dominatee(DT, Bs); 883286425Sdim 884286425Sdim // Traverse the loop nest upwards until we find a loop in which Node 885286425Sdim // is no longer invariant, or until we get to the upper limit of Node's 886286425Sdim // placement. The traversal will also stop when a suitable "preheader" 887286425Sdim // cannot be found for a given loop. The "preheader" may actually be 888286425Sdim // a regular block outside of the loop (i.e. not guarded), in which case 889286425Sdim // the Node will be speculated. 890286425Sdim // For nodes that are not in the main path of the containing loop (i.e. 891286425Sdim // are not executed in each iteration), do not move them out of the loop. 892286425Sdim BasicBlock *LocB = cast_or_null<BasicBlock>(Loc[Node]); 893286425Sdim if (LocB) { 894286425Sdim Loop *Lp = LI->getLoopFor(LocB); 895286425Sdim while (Lp) { 896286425Sdim if (!isInvariantIn(Node, Lp) || !isInMainPath(LocB, Lp)) 897286425Sdim break; 898286425Sdim BasicBlock *NewLoc = preheader(DT, Lp); 899286425Sdim if (!NewLoc || !DT->dominates(TopB, NewLoc)) 900286425Sdim break; 901286425Sdim Lp = Lp->getParentLoop(); 902286425Sdim LocB = NewLoc; 903286425Sdim } 904286425Sdim } 905286425Sdim Loc[Node] = LocB; 906286425Sdim 907286425Sdim // Recursively compute the locations of all children nodes. 908286425Sdim NodeChildrenMap::iterator CF = NCM.find(Node); 909286425Sdim if (CF != NCM.end()) { 910286425Sdim NodeVect &Cs = CF->second; 911286425Sdim for (NodeVect::iterator I = Cs.begin(), E = Cs.end(); I != E; ++I) 912286425Sdim adjustForInvariance(*I, NCM, Loc); 913286425Sdim } 914286425Sdim return LocB; 915286425Sdim} 916286425Sdim 917286425Sdim 918286425Sdimnamespace { 919286425Sdim struct LocationAsBlock { 920286425Sdim LocationAsBlock(const NodeToValueMap &L) : Map(L) {} 921286425Sdim const NodeToValueMap ⤅ 922286425Sdim }; 923286425Sdim 924286425Sdim raw_ostream &operator<< (raw_ostream &OS, 925286425Sdim const LocationAsBlock &Loc) LLVM_ATTRIBUTE_UNUSED ; 926286425Sdim raw_ostream &operator<< (raw_ostream &OS, const LocationAsBlock &Loc) { 927286425Sdim for (NodeToValueMap::const_iterator I = Loc.Map.begin(), E = Loc.Map.end(); 928286425Sdim I != E; ++I) { 929286425Sdim OS << I->first << " -> "; 930286425Sdim BasicBlock *B = cast<BasicBlock>(I->second); 931286425Sdim OS << B->getName() << '(' << B << ')'; 932286425Sdim OS << '\n'; 933286425Sdim } 934286425Sdim return OS; 935286425Sdim } 936286425Sdim 937286425Sdim inline bool is_constant(GepNode *N) { 938286425Sdim return isa<ConstantInt>(N->Idx); 939286425Sdim } 940286425Sdim} 941286425Sdim 942286425Sdim 943286425Sdimvoid HexagonCommonGEP::separateChainForNode(GepNode *Node, Use *U, 944286425Sdim NodeToValueMap &Loc) { 945286425Sdim User *R = U->getUser(); 946286425Sdim DEBUG(dbgs() << "Separating chain for node (" << Node << ") user: " 947286425Sdim << *R << '\n'); 948286425Sdim BasicBlock *PB = cast<Instruction>(R)->getParent(); 949286425Sdim 950286425Sdim GepNode *N = Node; 951286425Sdim GepNode *C = 0, *NewNode = 0; 952286425Sdim while (is_constant(N) && !(N->Flags & GepNode::Root)) { 953286425Sdim // XXX if (single-use) dont-replicate; 954286425Sdim GepNode *NewN = new (*Mem) GepNode(N); 955286425Sdim Nodes.push_back(NewN); 956286425Sdim Loc[NewN] = PB; 957286425Sdim 958286425Sdim if (N == Node) 959286425Sdim NewNode = NewN; 960286425Sdim NewN->Flags &= ~GepNode::Used; 961286425Sdim if (C) 962286425Sdim C->Parent = NewN; 963286425Sdim C = NewN; 964286425Sdim N = N->Parent; 965286425Sdim } 966286425Sdim if (!NewNode) 967286425Sdim return; 968286425Sdim 969286425Sdim // Move over all uses that share the same user as U from Node to NewNode. 970286425Sdim NodeToUsesMap::iterator UF = Uses.find(Node); 971286425Sdim assert(UF != Uses.end()); 972286425Sdim UseSet &Us = UF->second; 973286425Sdim UseSet NewUs; 974286425Sdim for (UseSet::iterator I = Us.begin(); I != Us.end(); ) { 975286425Sdim User *S = (*I)->getUser(); 976286425Sdim UseSet::iterator Nx = std::next(I); 977286425Sdim if (S == R) { 978286425Sdim NewUs.insert(*I); 979286425Sdim Us.erase(I); 980286425Sdim } 981286425Sdim I = Nx; 982286425Sdim } 983286425Sdim if (Us.empty()) { 984286425Sdim Node->Flags &= ~GepNode::Used; 985286425Sdim Uses.erase(UF); 986286425Sdim } 987286425Sdim 988286425Sdim // Should at least have U in NewUs. 989286425Sdim NewNode->Flags |= GepNode::Used; 990286425Sdim DEBUG(dbgs() << "new node: " << NewNode << " " << *NewNode << '\n'); 991286425Sdim assert(!NewUs.empty()); 992286425Sdim Uses[NewNode] = NewUs; 993286425Sdim} 994286425Sdim 995286425Sdim 996286425Sdimvoid HexagonCommonGEP::separateConstantChains(GepNode *Node, 997286425Sdim NodeChildrenMap &NCM, NodeToValueMap &Loc) { 998286425Sdim // First approximation: extract all chains. 999286425Sdim NodeSet Ns; 1000286425Sdim nodes_for_root(Node, NCM, Ns); 1001286425Sdim 1002286425Sdim DEBUG(dbgs() << "Separating constant chains for node: " << Node << '\n'); 1003286425Sdim // Collect all used nodes together with the uses from loads and stores, 1004286425Sdim // where the GEP node could be folded into the load/store instruction. 1005286425Sdim NodeToUsesMap FNs; // Foldable nodes. 1006286425Sdim for (NodeSet::iterator I = Ns.begin(), E = Ns.end(); I != E; ++I) { 1007286425Sdim GepNode *N = *I; 1008286425Sdim if (!(N->Flags & GepNode::Used)) 1009286425Sdim continue; 1010286425Sdim NodeToUsesMap::iterator UF = Uses.find(N); 1011286425Sdim assert(UF != Uses.end()); 1012286425Sdim UseSet &Us = UF->second; 1013286425Sdim // Loads/stores that use the node N. 1014286425Sdim UseSet LSs; 1015286425Sdim for (UseSet::iterator J = Us.begin(), F = Us.end(); J != F; ++J) { 1016286425Sdim Use *U = *J; 1017286425Sdim User *R = U->getUser(); 1018286425Sdim // We're interested in uses that provide the address. It can happen 1019286425Sdim // that the value may also be provided via GEP, but we won't handle 1020286425Sdim // those cases here for now. 1021286425Sdim if (LoadInst *Ld = dyn_cast<LoadInst>(R)) { 1022286425Sdim unsigned PtrX = LoadInst::getPointerOperandIndex(); 1023286425Sdim if (&Ld->getOperandUse(PtrX) == U) 1024286425Sdim LSs.insert(U); 1025286425Sdim } else if (StoreInst *St = dyn_cast<StoreInst>(R)) { 1026286425Sdim unsigned PtrX = StoreInst::getPointerOperandIndex(); 1027286425Sdim if (&St->getOperandUse(PtrX) == U) 1028286425Sdim LSs.insert(U); 1029286425Sdim } 1030286425Sdim } 1031286425Sdim // Even if the total use count is 1, separating the chain may still be 1032286425Sdim // beneficial, since the constant chain may be longer than the GEP alone 1033286425Sdim // would be (e.g. if the parent node has a constant index and also has 1034286425Sdim // other children). 1035286425Sdim if (!LSs.empty()) 1036286425Sdim FNs.insert(std::make_pair(N, LSs)); 1037286425Sdim } 1038286425Sdim 1039286425Sdim DEBUG(dbgs() << "Nodes with foldable users:\n" << FNs); 1040286425Sdim 1041286425Sdim for (NodeToUsesMap::iterator I = FNs.begin(), E = FNs.end(); I != E; ++I) { 1042286425Sdim GepNode *N = I->first; 1043286425Sdim UseSet &Us = I->second; 1044286425Sdim for (UseSet::iterator J = Us.begin(), F = Us.end(); J != F; ++J) 1045286425Sdim separateChainForNode(N, *J, Loc); 1046286425Sdim } 1047286425Sdim} 1048286425Sdim 1049286425Sdim 1050286425Sdimvoid HexagonCommonGEP::computeNodePlacement(NodeToValueMap &Loc) { 1051286425Sdim // Compute the inverse of the Node.Parent links. Also, collect the set 1052286425Sdim // of root nodes. 1053286425Sdim NodeChildrenMap NCM; 1054286425Sdim NodeVect Roots; 1055286425Sdim invert_find_roots(Nodes, NCM, Roots); 1056286425Sdim 1057286425Sdim // Compute the initial placement determined by the users' locations, and 1058286425Sdim // the locations of the child nodes. 1059286425Sdim for (NodeVect::iterator I = Roots.begin(), E = Roots.end(); I != E; ++I) 1060286425Sdim recalculatePlacementRec(*I, NCM, Loc); 1061286425Sdim 1062286425Sdim DEBUG(dbgs() << "Initial node placement:\n" << LocationAsBlock(Loc)); 1063286425Sdim 1064286425Sdim if (OptEnableInv) { 1065286425Sdim for (NodeVect::iterator I = Roots.begin(), E = Roots.end(); I != E; ++I) 1066286425Sdim adjustForInvariance(*I, NCM, Loc); 1067286425Sdim 1068286425Sdim DEBUG(dbgs() << "Node placement after adjustment for invariance:\n" 1069286425Sdim << LocationAsBlock(Loc)); 1070286425Sdim } 1071286425Sdim if (OptEnableConst) { 1072286425Sdim for (NodeVect::iterator I = Roots.begin(), E = Roots.end(); I != E; ++I) 1073286425Sdim separateConstantChains(*I, NCM, Loc); 1074286425Sdim } 1075286425Sdim DEBUG(dbgs() << "Node use information:\n" << Uses); 1076286425Sdim 1077286425Sdim // At the moment, there is no further refinement of the initial placement. 1078286425Sdim // Such a refinement could include splitting the nodes if they are placed 1079286425Sdim // too far from some of its users. 1080286425Sdim 1081286425Sdim DEBUG(dbgs() << "Final node placement:\n" << LocationAsBlock(Loc)); 1082286425Sdim} 1083286425Sdim 1084286425Sdim 1085286425SdimValue *HexagonCommonGEP::fabricateGEP(NodeVect &NA, BasicBlock::iterator At, 1086286425Sdim BasicBlock *LocB) { 1087286425Sdim DEBUG(dbgs() << "Fabricating GEP in " << LocB->getName() 1088286425Sdim << " for nodes:\n" << NA); 1089286425Sdim unsigned Num = NA.size(); 1090286425Sdim GepNode *RN = NA[0]; 1091286425Sdim assert((RN->Flags & GepNode::Root) && "Creating GEP for non-root"); 1092286425Sdim 1093286425Sdim Value *NewInst = 0; 1094286425Sdim Value *Input = RN->BaseVal; 1095286425Sdim Value **IdxList = new Value*[Num+1]; 1096286425Sdim unsigned nax = 0; 1097286425Sdim do { 1098286425Sdim unsigned IdxC = 0; 1099286425Sdim // If the type of the input of the first node is not a pointer, 1100286425Sdim // we need to add an artificial i32 0 to the indices (because the 1101286425Sdim // actual input in the IR will be a pointer). 1102286425Sdim if (!NA[nax]->PTy->isPointerTy()) { 1103286425Sdim Type *Int32Ty = Type::getInt32Ty(*Ctx); 1104286425Sdim IdxList[IdxC++] = ConstantInt::get(Int32Ty, 0); 1105286425Sdim } 1106286425Sdim 1107286425Sdim // Keep adding indices from NA until we have to stop and generate 1108286425Sdim // an "intermediate" GEP. 1109286425Sdim while (++nax <= Num) { 1110286425Sdim GepNode *N = NA[nax-1]; 1111286425Sdim IdxList[IdxC++] = N->Idx; 1112286425Sdim if (nax < Num) { 1113286425Sdim // We have to stop, if the expected type of the output of this node 1114286425Sdim // is not the same as the input type of the next node. 1115286425Sdim Type *NextTy = next_type(N->PTy, N->Idx); 1116286425Sdim if (NextTy != NA[nax]->PTy) 1117286425Sdim break; 1118286425Sdim } 1119286425Sdim } 1120286425Sdim ArrayRef<Value*> A(IdxList, IdxC); 1121286425Sdim Type *InpTy = Input->getType(); 1122286425Sdim Type *ElTy = cast<PointerType>(InpTy->getScalarType())->getElementType(); 1123296417Sdim NewInst = GetElementPtrInst::Create(ElTy, Input, A, "cgep", &*At); 1124286425Sdim DEBUG(dbgs() << "new GEP: " << *NewInst << '\n'); 1125286425Sdim Input = NewInst; 1126286425Sdim } while (nax <= Num); 1127286425Sdim 1128286425Sdim delete[] IdxList; 1129286425Sdim return NewInst; 1130286425Sdim} 1131286425Sdim 1132286425Sdim 1133286425Sdimvoid HexagonCommonGEP::getAllUsersForNode(GepNode *Node, ValueVect &Values, 1134286425Sdim NodeChildrenMap &NCM) { 1135286425Sdim NodeVect Work; 1136286425Sdim Work.push_back(Node); 1137286425Sdim 1138286425Sdim while (!Work.empty()) { 1139286425Sdim NodeVect::iterator First = Work.begin(); 1140286425Sdim GepNode *N = *First; 1141286425Sdim Work.erase(First); 1142286425Sdim if (N->Flags & GepNode::Used) { 1143286425Sdim NodeToUsesMap::iterator UF = Uses.find(N); 1144286425Sdim assert(UF != Uses.end() && "No use information for used node"); 1145286425Sdim UseSet &Us = UF->second; 1146286425Sdim for (UseSet::iterator I = Us.begin(), E = Us.end(); I != E; ++I) 1147286425Sdim Values.push_back((*I)->getUser()); 1148286425Sdim } 1149286425Sdim NodeChildrenMap::iterator CF = NCM.find(N); 1150286425Sdim if (CF != NCM.end()) { 1151286425Sdim NodeVect &Cs = CF->second; 1152286425Sdim Work.insert(Work.end(), Cs.begin(), Cs.end()); 1153286425Sdim } 1154286425Sdim } 1155286425Sdim} 1156286425Sdim 1157286425Sdim 1158286425Sdimvoid HexagonCommonGEP::materialize(NodeToValueMap &Loc) { 1159286425Sdim DEBUG(dbgs() << "Nodes before materialization:\n" << Nodes << '\n'); 1160286425Sdim NodeChildrenMap NCM; 1161286425Sdim NodeVect Roots; 1162286425Sdim // Compute the inversion again, since computing placement could alter 1163286425Sdim // "parent" relation between nodes. 1164286425Sdim invert_find_roots(Nodes, NCM, Roots); 1165286425Sdim 1166286425Sdim while (!Roots.empty()) { 1167286425Sdim NodeVect::iterator First = Roots.begin(); 1168286425Sdim GepNode *Root = *First, *Last = *First; 1169286425Sdim Roots.erase(First); 1170286425Sdim 1171286425Sdim NodeVect NA; // Nodes to assemble. 1172286425Sdim // Append to NA all child nodes up to (and including) the first child 1173286425Sdim // that: 1174286425Sdim // (1) has more than 1 child, or 1175286425Sdim // (2) is used, or 1176286425Sdim // (3) has a child located in a different block. 1177286425Sdim bool LastUsed = false; 1178286425Sdim unsigned LastCN = 0; 1179286425Sdim // The location may be null if the computation failed (it can legitimately 1180286425Sdim // happen for nodes created from dead GEPs). 1181286425Sdim Value *LocV = Loc[Last]; 1182286425Sdim if (!LocV) 1183286425Sdim continue; 1184286425Sdim BasicBlock *LastB = cast<BasicBlock>(LocV); 1185286425Sdim do { 1186286425Sdim NA.push_back(Last); 1187286425Sdim LastUsed = (Last->Flags & GepNode::Used); 1188286425Sdim if (LastUsed) 1189286425Sdim break; 1190286425Sdim NodeChildrenMap::iterator CF = NCM.find(Last); 1191286425Sdim LastCN = (CF != NCM.end()) ? CF->second.size() : 0; 1192286425Sdim if (LastCN != 1) 1193286425Sdim break; 1194286425Sdim GepNode *Child = CF->second.front(); 1195286425Sdim BasicBlock *ChildB = cast_or_null<BasicBlock>(Loc[Child]); 1196286425Sdim if (ChildB != 0 && LastB != ChildB) 1197286425Sdim break; 1198286425Sdim Last = Child; 1199286425Sdim } while (true); 1200286425Sdim 1201296417Sdim BasicBlock::iterator InsertAt = LastB->getTerminator()->getIterator(); 1202286425Sdim if (LastUsed || LastCN > 0) { 1203286425Sdim ValueVect Urs; 1204286425Sdim getAllUsersForNode(Root, Urs, NCM); 1205286425Sdim BasicBlock::iterator FirstUse = first_use_of_in_block(Urs, LastB); 1206286425Sdim if (FirstUse != LastB->end()) 1207286425Sdim InsertAt = FirstUse; 1208286425Sdim } 1209286425Sdim 1210286425Sdim // Generate a new instruction for NA. 1211286425Sdim Value *NewInst = fabricateGEP(NA, InsertAt, LastB); 1212286425Sdim 1213286425Sdim // Convert all the children of Last node into roots, and append them 1214286425Sdim // to the Roots list. 1215286425Sdim if (LastCN > 0) { 1216286425Sdim NodeVect &Cs = NCM[Last]; 1217286425Sdim for (NodeVect::iterator I = Cs.begin(), E = Cs.end(); I != E; ++I) { 1218286425Sdim GepNode *CN = *I; 1219286425Sdim CN->Flags &= ~GepNode::Internal; 1220286425Sdim CN->Flags |= GepNode::Root; 1221286425Sdim CN->BaseVal = NewInst; 1222286425Sdim Roots.push_back(CN); 1223286425Sdim } 1224286425Sdim } 1225286425Sdim 1226286425Sdim // Lastly, if the Last node was used, replace all uses with the new GEP. 1227286425Sdim // The uses reference the original GEP values. 1228286425Sdim if (LastUsed) { 1229286425Sdim NodeToUsesMap::iterator UF = Uses.find(Last); 1230286425Sdim assert(UF != Uses.end() && "No use information found"); 1231286425Sdim UseSet &Us = UF->second; 1232286425Sdim for (UseSet::iterator I = Us.begin(), E = Us.end(); I != E; ++I) { 1233286425Sdim Use *U = *I; 1234286425Sdim U->set(NewInst); 1235286425Sdim } 1236286425Sdim } 1237286425Sdim } 1238286425Sdim} 1239286425Sdim 1240286425Sdim 1241286425Sdimvoid HexagonCommonGEP::removeDeadCode() { 1242286425Sdim ValueVect BO; 1243286425Sdim BO.push_back(&Fn->front()); 1244286425Sdim 1245286425Sdim for (unsigned i = 0; i < BO.size(); ++i) { 1246286425Sdim BasicBlock *B = cast<BasicBlock>(BO[i]); 1247286425Sdim DomTreeNode *N = DT->getNode(B); 1248286425Sdim typedef GraphTraits<DomTreeNode*> GTN; 1249286425Sdim typedef GTN::ChildIteratorType Iter; 1250286425Sdim for (Iter I = GTN::child_begin(N), E = GTN::child_end(N); I != E; ++I) 1251286425Sdim BO.push_back((*I)->getBlock()); 1252286425Sdim } 1253286425Sdim 1254286425Sdim for (unsigned i = BO.size(); i > 0; --i) { 1255286425Sdim BasicBlock *B = cast<BasicBlock>(BO[i-1]); 1256286425Sdim BasicBlock::InstListType &IL = B->getInstList(); 1257286425Sdim typedef BasicBlock::InstListType::reverse_iterator reverse_iterator; 1258286425Sdim ValueVect Ins; 1259286425Sdim for (reverse_iterator I = IL.rbegin(), E = IL.rend(); I != E; ++I) 1260286425Sdim Ins.push_back(&*I); 1261286425Sdim for (ValueVect::iterator I = Ins.begin(), E = Ins.end(); I != E; ++I) { 1262286425Sdim Instruction *In = cast<Instruction>(*I); 1263286425Sdim if (isInstructionTriviallyDead(In)) 1264286425Sdim In->eraseFromParent(); 1265286425Sdim } 1266286425Sdim } 1267286425Sdim} 1268286425Sdim 1269286425Sdim 1270286425Sdimbool HexagonCommonGEP::runOnFunction(Function &F) { 1271286425Sdim // For now bail out on C++ exception handling. 1272286425Sdim for (Function::iterator A = F.begin(), Z = F.end(); A != Z; ++A) 1273286425Sdim for (BasicBlock::iterator I = A->begin(), E = A->end(); I != E; ++I) 1274286425Sdim if (isa<InvokeInst>(I) || isa<LandingPadInst>(I)) 1275286425Sdim return false; 1276286425Sdim 1277286425Sdim Fn = &F; 1278286425Sdim DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree(); 1279286425Sdim PDT = &getAnalysis<PostDominatorTree>(); 1280286425Sdim LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo(); 1281286425Sdim Ctx = &F.getContext(); 1282286425Sdim 1283286425Sdim Nodes.clear(); 1284286425Sdim Uses.clear(); 1285286425Sdim NodeOrder.clear(); 1286286425Sdim 1287286425Sdim SpecificBumpPtrAllocator<GepNode> Allocator; 1288286425Sdim Mem = &Allocator; 1289286425Sdim 1290286425Sdim collect(); 1291286425Sdim common(); 1292286425Sdim 1293286425Sdim NodeToValueMap Loc; 1294286425Sdim computeNodePlacement(Loc); 1295286425Sdim materialize(Loc); 1296286425Sdim removeDeadCode(); 1297286425Sdim 1298286425Sdim#ifdef XDEBUG 1299286425Sdim // Run this only when expensive checks are enabled. 1300286425Sdim verifyFunction(F); 1301286425Sdim#endif 1302286425Sdim return true; 1303286425Sdim} 1304286425Sdim 1305286425Sdim 1306286425Sdimnamespace llvm { 1307286425Sdim FunctionPass *createHexagonCommonGEP() { 1308286425Sdim return new HexagonCommonGEP(); 1309286425Sdim } 1310286425Sdim} 1311