1 //===-- lib/CodeGen/MachineInstrBundle.cpp --------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "llvm/CodeGen/MachineInstrBundle.h"
11 #include "llvm/CodeGen/MachineInstrBuilder.h"
12 #include "llvm/CodeGen/Passes.h"
13 #include "llvm/CodeGen/MachineFunctionPass.h"
14 #include "llvm/Target/TargetInstrInfo.h"
15 #include "llvm/Target/TargetMachine.h"
16 #include "llvm/Target/TargetRegisterInfo.h"
17 #include "llvm/ADT/SmallSet.h"
18 #include "llvm/ADT/SmallVector.h"
22 class UnpackMachineBundles : public MachineFunctionPass {
24 static char ID; // Pass identification
25 UnpackMachineBundles() : MachineFunctionPass(ID) {
26 initializeUnpackMachineBundlesPass(*PassRegistry::getPassRegistry());
29 virtual bool runOnMachineFunction(MachineFunction &MF);
31 } // end anonymous namespace
33 char UnpackMachineBundles::ID = 0;
34 char &llvm::UnpackMachineBundlesID = UnpackMachineBundles::ID;
35 INITIALIZE_PASS(UnpackMachineBundles, "unpack-mi-bundles",
36 "Unpack machine instruction bundles", false, false)
38 bool UnpackMachineBundles::runOnMachineFunction(MachineFunction &MF) {
40 for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) {
41 MachineBasicBlock *MBB = &*I;
43 for (MachineBasicBlock::instr_iterator MII = MBB->instr_begin(),
44 MIE = MBB->instr_end(); MII != MIE; ) {
45 MachineInstr *MI = &*MII;
47 // Remove BUNDLE instruction and the InsideBundle flags from bundled
50 while (++MII != MIE && MII->isInsideBundle()) {
51 MII->setIsInsideBundle(false);
52 for (unsigned i = 0, e = MII->getNumOperands(); i != e; ++i) {
53 MachineOperand &MO = MII->getOperand(i);
54 if (MO.isReg() && MO.isInternalRead())
55 MO.setIsInternalRead(false);
58 MI->eraseFromParent();
73 class FinalizeMachineBundles : public MachineFunctionPass {
75 static char ID; // Pass identification
76 FinalizeMachineBundles() : MachineFunctionPass(ID) {
77 initializeFinalizeMachineBundlesPass(*PassRegistry::getPassRegistry());
80 virtual bool runOnMachineFunction(MachineFunction &MF);
82 } // end anonymous namespace
84 char FinalizeMachineBundles::ID = 0;
85 char &llvm::FinalizeMachineBundlesID = FinalizeMachineBundles::ID;
86 INITIALIZE_PASS(FinalizeMachineBundles, "finalize-mi-bundles",
87 "Finalize machine instruction bundles", false, false)
89 bool FinalizeMachineBundles::runOnMachineFunction(MachineFunction &MF) {
90 return llvm::finalizeBundles(MF);
94 /// finalizeBundle - Finalize a machine instruction bundle which includes
95 /// a sequence of instructions starting from FirstMI to LastMI (exclusive).
96 /// This routine adds a BUNDLE instruction to represent the bundle, it adds
97 /// IsInternalRead markers to MachineOperands which are defined inside the
98 /// bundle, and it copies externally visible defs and uses to the BUNDLE
100 void llvm::finalizeBundle(MachineBasicBlock &MBB,
101 MachineBasicBlock::instr_iterator FirstMI,
102 MachineBasicBlock::instr_iterator LastMI) {
103 assert(FirstMI != LastMI && "Empty bundle?");
105 const TargetMachine &TM = MBB.getParent()->getTarget();
106 const TargetInstrInfo *TII = TM.getInstrInfo();
107 const TargetRegisterInfo *TRI = TM.getRegisterInfo();
109 MachineInstrBuilder MIB = BuildMI(MBB, FirstMI, FirstMI->getDebugLoc(),
110 TII->get(TargetOpcode::BUNDLE));
112 SmallVector<unsigned, 8> LocalDefs;
113 SmallSet<unsigned, 8> LocalDefSet;
114 SmallSet<unsigned, 8> DeadDefSet;
115 SmallSet<unsigned, 8> KilledDefSet;
116 SmallVector<unsigned, 8> ExternUses;
117 SmallSet<unsigned, 8> ExternUseSet;
118 SmallSet<unsigned, 8> KilledUseSet;
119 SmallSet<unsigned, 8> UndefUseSet;
120 SmallVector<MachineOperand*, 4> Defs;
121 for (; FirstMI != LastMI; ++FirstMI) {
122 for (unsigned i = 0, e = FirstMI->getNumOperands(); i != e; ++i) {
123 MachineOperand &MO = FirstMI->getOperand(i);
131 unsigned Reg = MO.getReg();
134 assert(TargetRegisterInfo::isPhysicalRegister(Reg));
135 if (LocalDefSet.count(Reg)) {
136 MO.setIsInternalRead();
138 // Internal def is now killed.
139 KilledDefSet.insert(Reg);
141 if (ExternUseSet.insert(Reg)) {
142 ExternUses.push_back(Reg);
144 UndefUseSet.insert(Reg);
147 // External def is now killed.
148 KilledUseSet.insert(Reg);
152 for (unsigned i = 0, e = Defs.size(); i != e; ++i) {
153 MachineOperand &MO = *Defs[i];
154 unsigned Reg = MO.getReg();
158 if (LocalDefSet.insert(Reg)) {
159 LocalDefs.push_back(Reg);
161 DeadDefSet.insert(Reg);
164 // Re-defined inside the bundle, it's no longer killed.
165 KilledDefSet.erase(Reg);
167 // Previously defined but dead.
168 DeadDefSet.erase(Reg);
172 for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs) {
173 unsigned SubReg = *SubRegs;
174 if (LocalDefSet.insert(SubReg))
175 LocalDefs.push_back(SubReg);
180 FirstMI->setIsInsideBundle();
184 SmallSet<unsigned, 8> Added;
185 for (unsigned i = 0, e = LocalDefs.size(); i != e; ++i) {
186 unsigned Reg = LocalDefs[i];
187 if (Added.insert(Reg)) {
188 // If it's not live beyond end of the bundle, mark it dead.
189 bool isDead = DeadDefSet.count(Reg) || KilledDefSet.count(Reg);
190 MIB.addReg(Reg, getDefRegState(true) | getDeadRegState(isDead) |
191 getImplRegState(true));
195 for (unsigned i = 0, e = ExternUses.size(); i != e; ++i) {
196 unsigned Reg = ExternUses[i];
197 bool isKill = KilledUseSet.count(Reg);
198 bool isUndef = UndefUseSet.count(Reg);
199 MIB.addReg(Reg, getKillRegState(isKill) | getUndefRegState(isUndef) |
200 getImplRegState(true));
204 /// finalizeBundle - Same functionality as the previous finalizeBundle except
205 /// the last instruction in the bundle is not provided as an input. This is
206 /// used in cases where bundles are pre-determined by marking instructions
207 /// with 'InsideBundle' marker. It returns the MBB instruction iterator that
208 /// points to the end of the bundle.
209 MachineBasicBlock::instr_iterator
210 llvm::finalizeBundle(MachineBasicBlock &MBB,
211 MachineBasicBlock::instr_iterator FirstMI) {
212 MachineBasicBlock::instr_iterator E = MBB.instr_end();
213 MachineBasicBlock::instr_iterator LastMI = llvm::next(FirstMI);
214 while (LastMI != E && LastMI->isInsideBundle())
216 finalizeBundle(MBB, FirstMI, LastMI);
220 /// finalizeBundles - Finalize instruction bundles in the specified
221 /// MachineFunction. Return true if any bundles are finalized.
222 bool llvm::finalizeBundles(MachineFunction &MF) {
223 bool Changed = false;
224 for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) {
225 MachineBasicBlock &MBB = *I;
227 MachineBasicBlock::instr_iterator MII = MBB.instr_begin();
228 assert(!MII->isInsideBundle() &&
229 "First instr cannot be inside bundle before finalization!");
231 MachineBasicBlock::instr_iterator MIE = MBB.instr_end();
234 for (++MII; MII != MIE; ) {
235 if (!MII->isInsideBundle())
238 MII = finalizeBundle(MBB, llvm::prior(MII));
247 //===----------------------------------------------------------------------===//
248 // MachineOperand iterator
249 //===----------------------------------------------------------------------===//
251 MachineOperandIteratorBase::RegInfo
252 MachineOperandIteratorBase::analyzeVirtReg(unsigned Reg,
253 SmallVectorImpl<std::pair<MachineInstr*, unsigned> > *Ops) {
254 RegInfo RI = { false, false, false };
255 for(; isValid(); ++*this) {
256 MachineOperand &MO = deref();
257 if (!MO.isReg() || MO.getReg() != Reg)
260 // Remember each (MI, OpNo) that refers to Reg.
262 Ops->push_back(std::make_pair(MO.getParent(), getOperandNo()));
264 // Both defs and uses can read virtual registers.
271 // Only defs can write.
274 else if (!RI.Tied && MO.getParent()->isRegTiedToDefOperand(getOperandNo()))