106 class Chain;
137   bool colorChainSet(std::vector<Chain*> GV, MachineBasicBlock &MBB,
139   bool colorChain(Chain *G, Color C, MachineBasicBlock &MBB);
140   int scavengeRegister(Chain *G, Color C, MachineBasicBlock &MBB);
142                        std::map<unsigned, Chain*> &Active,
143                        std::vector<std::unique_ptr<Chain>> &AllChains);
145                       std::map<unsigned, Chain*> &RegChains);
147   Chain *getAndEraseNext(Color PreferredColor, std::vector<Chain*> &L);
159 /// A Chain is a sequence of instructions that are linked together by
167 /// do not belong to the chain. These other instructions must not use
168 /// the "chain" register at any point.
170 /// We currently only support chains where the "chain" operand is killed
171 /// at each link in the chain for simplicity.
172 /// A chain has three important instructions - Start, Last and Kill.
173 ///   * The start instruction is the first instruction in the chain.
174 ///   * Last is the final instruction in the chain.
184 class Chain {  class
191   /// All instructions in the chain.
197   /// The "color" of LastInst. This will be the preferred chain color,
202   Chain(MachineInstr *MI, unsigned Idx, Color C)  in Chain()  function in __anondfbe7f5c0211::Chain
209   /// Add a new instruction into the chain. The instruction's dest operand
216            "Chain: broken invariant. A Chain can only be killed after its last "  in add()
222   /// Return true if MI is a member of the chain.
225   /// Return the number of instructions in the chain.
230   /// Inform the chain that its last active register (the dest register of
237            "Chain: broken invariant. A Chain can only be killed after its last "  in setKill()
241   /// Return the first instruction in the chain.
243   /// Return the last instruction in the chain.
248   /// of the chain. This is the maximum of KillInst (if set) and LastInst.
257   /// Return the preferred color of this chain.
264   /// Return true if this chain (StartInst..KillInst) overlaps with Other.
265   bool rangeOverlapsWith(const Chain &Other) const {  in rangeOverlapsWith()
273   /// Return true if this chain starts before Other.
274   bool startsBefore(const Chain *Other) const {  in startsBefore()
283   /// Return a simple string representation of the chain.
338   // "link" register between each inst in the chain.  in runOnBasicBlock()
339   std::map<unsigned, Chain*> ActiveChains;  in runOnBasicBlock()
340   std::vector<std::unique_ptr<Chain>> AllChains;  in runOnBasicBlock()
355   EquivalenceClasses<Chain*> EC;  in runOnBasicBlock()
369   std::vector<std::vector<Chain*> > V;  in runOnBasicBlock()
371     std::vector<Chain*> Cs(EC.member_begin(I), EC.member_end());  in runOnBasicBlock()
379              [](const std::vector<Chain *> &A, const std::vector<Chain *> &B) {  in runOnBasicBlock()
402 Chain *AArch64A57FPLoadBalancing::getAndEraseNext(Color PreferredColor,  in getAndEraseNext()
403                                                   std::vector<Chain*> &L) {  in getAndEraseNext()
410   // but if we can't find a chain of the maximum length with the preferred color,  in getAndEraseNext()
412   // returning a chain that must be recolored.  in getAndEraseNext()
420       Chain *Ch = *--I;  in getAndEraseNext()
426       Chain *Ch = *I;  in getAndEraseNext()
433   Chain *Ch = L.front();  in getAndEraseNext()
438 bool AArch64A57FPLoadBalancing::colorChainSet(std::vector<Chain*> GV,  in colorChainSet()
453   llvm::sort(GV, [](const Chain *G1, const Chain *G2) {  in colorChainSet()
465   while (Chain *G = getAndEraseNext(PreferredColor, GV)) {  in colorChainSet()
469       // But if we really don't care, use the chain's preferred color.  in colorChainSet()
495 int AArch64A57FPLoadBalancing::scavengeRegister(Chain *G, Color C,  in scavengeRegister()
498   // of the chain? Simulate liveness backwards until the end of the chain.  in scavengeRegister()
508   // Check which register units are alive throughout the chain.  in scavengeRegister()
510   assert(ChainBegin != ChainEnd && "Chain should contain instructions");  in scavengeRegister()
529 bool AArch64A57FPLoadBalancing::colorChain(Chain *G, Color C,  in colorChain()
600     MachineInstr *MI, unsigned Idx, std::map<unsigned, Chain *> &ActiveChains,  in scanInstruction()
601     std::vector<std::unique_ptr<Chain>> &AllChains) {  in scanInstruction()
611     // Create a new chain. Multiplies don't require forwarding so can go on any  in scanInstruction()
615     LLVM_DEBUG(dbgs() << "New chain started for register "  in scanInstruction()
618     auto G = std::make_unique<Chain>(MI, Idx, getColor(DestReg));  in scanInstruction()
635       LLVM_DEBUG(dbgs() << "Chain found for accumulator register "  in scanInstruction()
638       // For simplicity we only chain together sequences of MULs/MLAs where the  in scanInstruction()
644         // Add to chain.  in scanInstruction()
645         LLVM_DEBUG(dbgs() << "Instruction was successfully added to chain.\n");  in scanInstruction()
656           dbgs() << "Cannot add to chain because accumulator operand wasn't "  in scanInstruction()
661     LLVM_DEBUG(dbgs() << "Creating new chain for dest register "  in scanInstruction()
663     auto G = std::make_unique<Chain>(MI, Idx, getColor(DestReg));  in scanInstruction()
669     // Non-MUL or MLA instruction. Invalidate any chain in the uses or defs  in scanInstruction()
681                std::map<unsigned, Chain*> &ActiveChains) {  in maybeKillChain()
683   // determine if a chain should be ended and remove from ActiveChains.  in maybeKillChain()
688     // If this is a KILL of a current chain, record it.  in maybeKillChain()
690       LLVM_DEBUG(dbgs() << "Kill seen for chain " << printReg(MO.getReg(), TRI)  in maybeKillChain()
701         LLVM_DEBUG(dbgs() << "Kill (regmask) seen for chain "  in maybeKillChain()