DelaySlotFiller.cpp revision f152fe8d487c46873bbdd4abab43200f783e978b
19f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson//===-- DelaySlotFiller.cpp - SPARC delay slot filler ---------------------===// 29f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// 39f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// The LLVM Compiler Infrastructure 49f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// 59f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// This file is distributed under the University of Illinois Open Source 69f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// License. See LICENSE.TXT for details. 79f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// 89f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson//===----------------------------------------------------------------------===// 99f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// 109f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// This is a simple local pass that attempts to fill delay slots with useful 119f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// instructions. If no instructions can be moved into the delay slot, then a 129f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson// NOP is placed. 139f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson//===----------------------------------------------------------------------===// 149f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 159f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#define DEBUG_TYPE "delay-slot-filler" 169f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "Sparc.h" 179f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/CodeGen/MachineFunctionPass.h" 189f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/CodeGen/MachineInstrBuilder.h" 199f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/Support/CommandLine.h" 209f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/Target/TargetMachine.h" 219f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/Target/TargetInstrInfo.h" 229f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/Target/TargetRegisterInfo.h" 239f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/ADT/SmallSet.h" 249f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson#include "llvm/ADT/Statistic.h" 259f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 269f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonusing namespace llvm; 279f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 289f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse WilsonSTATISTIC(FilledSlots, "Number of delay slots filled"); 299f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 309f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonstatic cl::opt<bool> DisableDelaySlotFiller( 319f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson "disable-sparc-delay-filler", 329f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson cl::init(false), 339f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson cl::desc("Disable the Sparc delay slot filler."), 349f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson cl::Hidden); 359f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 369f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonnamespace { 379f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson struct Filler : public MachineFunctionPass { 389f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson /// Target machine description which we query for reg. names, data 399f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson /// layout, etc. 409f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson /// 419f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson TargetMachine &TM; 429f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson const TargetInstrInfo *TII; 439f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 449f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson static char ID; 459f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson Filler(TargetMachine &tm) 469f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson : MachineFunctionPass(ID), TM(tm), TII(tm.getInstrInfo()) { } 479f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 489f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson virtual const char *getPassName() const { 499f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return "SPARC Delay Slot Filler"; 509f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 519f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 529f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool runOnMachineBasicBlock(MachineBasicBlock &MBB); 539f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool runOnMachineFunction(MachineFunction &F) { 549f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool Changed = false; 559f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson for (MachineFunction::iterator FI = F.begin(), FE = F.end(); 569f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson FI != FE; ++FI) 579f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson Changed |= runOnMachineBasicBlock(*FI); 589f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return Changed; 599f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 609f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 619f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool isDelayFiller(MachineBasicBlock &MBB, 629f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator candidate); 639f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 649f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson void insertCallUses(MachineBasicBlock::iterator MI, 659f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32>& RegUses); 669f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 679f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson void insertDefsUses(MachineBasicBlock::iterator MI, 689f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32>& RegDefs, 699f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32>& RegUses); 709f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 719f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool IsRegInSet(SmallSet<unsigned, 32>& RegSet, 729f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson unsigned Reg); 739f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 749f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool delayHasHazard(MachineBasicBlock::iterator candidate, 759f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool &sawLoad, bool &sawStore, 769f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32> &RegDefs, 779f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32> &RegUses); 789f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 799f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator 809f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson findDelayInstr(MachineBasicBlock &MBB, MachineBasicBlock::iterator slot); 819f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 829f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool needsUnimp(MachineBasicBlock::iterator I, unsigned &StructSize); 839f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 849f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson }; 859f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson char Filler::ID = 0; 869f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson} // end of anonymous namespace 879f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 889f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/// createSparcDelaySlotFillerPass - Returns a pass that fills in delay 899f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/// slots in Sparc MachineFunctions 909f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/// 919f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse WilsonFunctionPass *llvm::createSparcDelaySlotFillerPass(TargetMachine &tm) { 929f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return new Filler(tm); 939f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson} 949f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 959f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 969f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/// runOnMachineBasicBlock - Fill in delay slots for the given basic block. 979f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/// We assume there is only one delay slot per delayed instruction. 989f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson/// 999f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilsonbool Filler::runOnMachineBasicBlock(MachineBasicBlock &MBB) { 1009f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool Changed = false; 1019f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1029f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson for (MachineBasicBlock::iterator I = MBB.begin(); I != MBB.end(); ++I) 1039f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (I->hasDelaySlot()) { 1049f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator D = MBB.end(); 1059f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator J = I; 1069f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1079f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (!DisableDelaySlotFiller) 1089f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson D = findDelayInstr(MBB, I); 1099f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1109f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson ++FilledSlots; 1119f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson Changed = true; 1129f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1139f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (D == MBB.end()) 1149f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson BuildMI(MBB, ++J, I->getDebugLoc(), TII->get(SP::NOP)); 1159f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson else 1169f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MBB.splice(++J, &MBB, D); 1179f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson unsigned structSize = 0; 1189f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (needsUnimp(I, structSize)) { 1199f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator J = I; 1209f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson ++J; //skip the delay filler. 1219f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson BuildMI(MBB, ++J, I->getDebugLoc(), 1229f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson TII->get(SP::UNIMP)).addImm(structSize); 1239f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 1249f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 1259f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return Changed; 1269f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson} 1279f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1289f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse WilsonMachineBasicBlock::iterator 1299f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse WilsonFiller::findDelayInstr(MachineBasicBlock &MBB, 1309f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator slot) 1319f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson{ 1329f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32> RegDefs; 1339f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson SmallSet<unsigned, 32> RegUses; 1349f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool sawLoad = false; 1359f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool sawStore = false; 1369f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1379f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson MachineBasicBlock::iterator I = slot; 1389f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1399f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (slot->getOpcode() == SP::RET) 1409f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return MBB.end(); 1419f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1429f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (slot->getOpcode() == SP::RETL) { 1439f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson --I; 1449f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (I->getOpcode() != SP::RESTORErr) 1459f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return MBB.end(); 1469f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson //change retl to ret 1479f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson slot->setDesc(TII->get(SP::RET)); 1489f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson return I; 1499f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson } 1509f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1519f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson //Call's delay filler can def some of call's uses. 1529f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (slot->isCall()) 1539f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson insertCallUses(slot, RegUses); 1549f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson else 1559f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson insertDefsUses(slot, RegDefs, RegUses); 1569f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1579f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson bool done = false; 1589f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1599f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson while (!done) { 1609f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson done = (I == MBB.begin()); 1619f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1629f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (!done) 1639f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson --I; 1649f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1659f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson // skip debug value 1669f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (I->isDebugValue()) 1679f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson continue; 1689f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1699f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson 1709f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson if (I->hasUnmodeledSideEffects() 1719f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson || I->isInlineAsm() 1729f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson || I->isLabel() 1739f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson || I->hasDelaySlot() 1749f8118474e9513f7a5b7d2a05e4a0fb15d1a6569Jesse Wilson || isDelayFiller(MBB, I)) 175 break; 176 177 if (delayHasHazard(I, sawLoad, sawStore, RegDefs, RegUses)) { 178 insertDefsUses(I, RegDefs, RegUses); 179 continue; 180 } 181 182 return I; 183 } 184 return MBB.end(); 185} 186 187bool Filler::delayHasHazard(MachineBasicBlock::iterator candidate, 188 bool &sawLoad, 189 bool &sawStore, 190 SmallSet<unsigned, 32> &RegDefs, 191 SmallSet<unsigned, 32> &RegUses) 192{ 193 194 if (candidate->isImplicitDef() || candidate->isKill()) 195 return true; 196 197 if (candidate->mayLoad()) { 198 sawLoad = true; 199 if (sawStore) 200 return true; 201 } 202 203 if (candidate->mayStore()) { 204 if (sawStore) 205 return true; 206 sawStore = true; 207 if (sawLoad) 208 return true; 209 } 210 211 for (unsigned i = 0, e = candidate->getNumOperands(); i!= e; ++i) { 212 const MachineOperand &MO = candidate->getOperand(i); 213 if (!MO.isReg()) 214 continue; // skip 215 216 unsigned Reg = MO.getReg(); 217 218 if (MO.isDef()) { 219 //check whether Reg is defined or used before delay slot. 220 if (IsRegInSet(RegDefs, Reg) || IsRegInSet(RegUses, Reg)) 221 return true; 222 } 223 if (MO.isUse()) { 224 //check whether Reg is defined before delay slot. 225 if (IsRegInSet(RegDefs, Reg)) 226 return true; 227 } 228 } 229 return false; 230} 231 232 233void Filler::insertCallUses(MachineBasicBlock::iterator MI, 234 SmallSet<unsigned, 32>& RegUses) 235{ 236 237 switch(MI->getOpcode()) { 238 default: llvm_unreachable("Unknown opcode."); 239 case SP::CALL: break; 240 case SP::JMPLrr: 241 case SP::JMPLri: 242 assert(MI->getNumOperands() >= 2); 243 const MachineOperand &Reg = MI->getOperand(0); 244 assert(Reg.isReg() && "JMPL first operand is not a register."); 245 assert(Reg.isUse() && "JMPL first operand is not a use."); 246 RegUses.insert(Reg.getReg()); 247 248 const MachineOperand &RegOrImm = MI->getOperand(1); 249 if (RegOrImm.isImm()) 250 break; 251 assert(RegOrImm.isReg() && "JMPLrr second operand is not a register."); 252 assert(RegOrImm.isUse() && "JMPLrr second operand is not a use."); 253 RegUses.insert(RegOrImm.getReg()); 254 break; 255 } 256} 257 258//Insert Defs and Uses of MI into the sets RegDefs and RegUses. 259void Filler::insertDefsUses(MachineBasicBlock::iterator MI, 260 SmallSet<unsigned, 32>& RegDefs, 261 SmallSet<unsigned, 32>& RegUses) 262{ 263 for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { 264 const MachineOperand &MO = MI->getOperand(i); 265 if (!MO.isReg()) 266 continue; 267 268 unsigned Reg = MO.getReg(); 269 if (Reg == 0) 270 continue; 271 if (MO.isDef()) 272 RegDefs.insert(Reg); 273 if (MO.isUse()) 274 RegUses.insert(Reg); 275 276 } 277} 278 279//returns true if the Reg or its alias is in the RegSet. 280bool Filler::IsRegInSet(SmallSet<unsigned, 32>& RegSet, unsigned Reg) 281{ 282 // Check Reg and all aliased Registers. 283 for (MCRegAliasIterator AI(Reg, TM.getRegisterInfo(), true); 284 AI.isValid(); ++AI) 285 if (RegSet.count(*AI)) 286 return true; 287 return false; 288} 289 290// return true if the candidate is a delay filler. 291bool Filler::isDelayFiller(MachineBasicBlock &MBB, 292 MachineBasicBlock::iterator candidate) 293{ 294 if (candidate == MBB.begin()) 295 return false; 296 if (candidate->getOpcode() == SP::UNIMP) 297 return true; 298 --candidate; 299 return candidate->hasDelaySlot(); 300} 301 302bool Filler::needsUnimp(MachineBasicBlock::iterator I, unsigned &StructSize) 303{ 304 if (!I->isCall()) 305 return false; 306 307 unsigned structSizeOpNum = 0; 308 switch (I->getOpcode()) { 309 default: llvm_unreachable("Unknown call opcode."); 310 case SP::CALL: structSizeOpNum = 1; break; 311 case SP::JMPLrr: 312 case SP::JMPLri: structSizeOpNum = 2; break; 313 } 314 315 const MachineOperand &MO = I->getOperand(structSizeOpNum); 316 if (!MO.isImm()) 317 return false; 318 StructSize = MO.getImm(); 319 return true; 320} 321