Move register class name strings to a single array in MCRegisterInfo to reduce static table size and number of relocation entries.

Indices into the table are stored in each MCRegisterClass instead of a pointer. A new method, getRegClassName, is added to MCRegisterInfo and TargetRegisterInfo to lookup the string in the table.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@222118 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/MC/MCRegisterInfo.h

@@ -32,9 +32,9 @@ public:
   typedef const MCPhysReg* iterator;
   typedef const MCPhysReg* const_iterator;
 
-  const char *Name;
   const iterator RegsBegin;
   const uint8_t *const RegSet;
+  const uint32_t NameIdx;
   const uint16_t RegsSize;
   const uint16_t RegSetSize;
   const uint16_t ID;
@@ -46,10 +46,6 @@ public:
   ///
   unsigned getID() const { return ID; }
 
-  /// getName() - Return the register class name for debugging.
-  ///
-  const char *getName() const { return Name; }
-
   /// begin/end - Return all of the registers in this class.
   ///
   iterator       begin() const { return RegsBegin; }
@@ -162,6 +158,7 @@ private:
   const MCPhysReg (*RegUnitRoots)[2];         // Pointer to regunit root table.
   const MCPhysReg *DiffLists;                 // Pointer to the difflists array
   const char *RegStrings;                     // Pointer to the string table.
+  const char *RegClassStrings;                // Pointer to the class strings.
   const uint16_t *SubRegIndices;              // Pointer to the subreg lookup
                                               // array.
   const SubRegCoveredBits *SubRegIdxRanges;   // Pointer to the subreg covered
@@ -243,6 +240,7 @@ public:
                           unsigned NRU,
                           const MCPhysReg *DL,
                           const char *Strings,
+                          const char *ClassStrings,
                           const uint16_t *SubIndices,
                           unsigned NumIndices,
                           const SubRegCoveredBits *SubIdxRanges,
@@ -254,6 +252,7 @@ public:
     Classes = C;
     DiffLists = DL;
     RegStrings = Strings;
+    RegClassStrings = ClassStrings;
     NumClasses = NC;
     RegUnitRoots = RURoots;
     NumRegUnits = NRU;
@@ -401,6 +400,10 @@ public:
     return Classes[i];
   }
 
+  const char *getRegClassName(const MCRegisterClass *Class) const {
+    return RegClassStrings + Class->NameIdx;
+  }
+
    /// \brief Returns the encoding for RegNo
   uint16_t getEncodingValue(unsigned RegNo) const {
     assert(RegNo < NumRegs &&

include/llvm/Target/TargetRegisterInfo.h

@@ -52,10 +52,6 @@ public:
   ///
   unsigned getID() const { return MC->getID(); }
 
-  /// getName() - Return the register class name for debugging.
-  ///
-  const char *getName() const { return MC->getName(); }
-
   /// begin/end - Return all of the registers in this class.
   ///
   iterator       begin() const { return MC->begin(); }
@@ -561,6 +557,11 @@ public:
     return RegClassBegin[i];
   }
 
+  /// getRegClassName - Returns the name of the register class.
+  const char *getRegClassName(const TargetRegisterClass *Class) const {
+    return MCRegisterInfo::getRegClassName(Class->MC);
+  }
+
   /// getCommonSubClass - find the largest common subclass of A and B. Return
   /// NULL if there is no common subclass.
   const TargetRegisterClass *

lib/CodeGen/AggressiveAntiDepBreaker.cpp

@@ -518,7 +518,7 @@ BitVector AggressiveAntiDepBreaker::GetRenameRegisters(unsigned Reg) {
       BV &= RCBV;
     }
 
-    DEBUG(dbgs() << " " << RC->getName());
+    DEBUG(dbgs() << " " << TRI->getRegClassName(RC));
   }
 
   return BV;

lib/CodeGen/ExecutionDepsFix.cpp

@@ -720,7 +720,7 @@ bool ExeDepsFix::runOnMachineFunction(MachineFunction &mf) {
   assert(NumRegs == RC->getNumRegs() && "Bad regclass");
 
   DEBUG(dbgs() << "********** FIX EXECUTION DEPENDENCIES: "
-               << RC->getName() << " **********\n");
+               << TRI->getRegClassName(RC) << " **********\n");
 
   // If no relevant registers are used in the function, we can skip it
   // completely.

lib/CodeGen/InlineSpiller.cpp

@@ -1377,7 +1377,7 @@ void InlineSpiller::spill(LiveRangeEdit &edit) {
   StackInt = nullptr;
 
   DEBUG(dbgs() << "Inline spilling "
-               << MRI.getRegClass(edit.getReg())->getName()
+               << TRI.getRegClassName(MRI.getRegClass(edit.getReg()))
                << ':' << edit.getParent()
                << "\nFrom original " << PrintReg(Original) << '\n');
   assert(edit.getParent().isSpillable() &&

lib/CodeGen/LiveRangeEdit.cpp

@@ -411,8 +411,11 @@ LiveRangeEdit::calculateRegClassAndHint(MachineFunction &MF,
   for (unsigned I = 0, Size = size(); I < Size; ++I) {
     LiveInterval &LI = LIS.getInterval(get(I));
     if (MRI.recomputeRegClass(LI.reg, MF.getTarget()))
-      DEBUG(dbgs() << "Inflated " << PrintReg(LI.reg) << " to "
-                   << MRI.getRegClass(LI.reg)->getName() << '\n');
+      DEBUG({
+        const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
+        dbgs() << "Inflated " << PrintReg(LI.reg) << " to "
+               << TRI->getRegClassName(MRI.getRegClass(LI.reg)) << '\n'
+      });
     VRAI.calculateSpillWeightAndHint(LI);
   }
 }

lib/CodeGen/LiveStackAnalysis.cpp

@@ -81,7 +81,7 @@ void LiveStacks::print(raw_ostream &OS, const Module*) const {
     int Slot = I->first;
     const TargetRegisterClass *RC = getIntervalRegClass(Slot);
     if (RC)
-      OS << " [" << RC->getName() << "]\n";
+      OS << " [" << TRI->getRegClassName(RC) << "]\n";
     else
       OS << " [Unknown]\n";
   }

lib/CodeGen/MachineInstr.cpp

@@ -1607,18 +1607,17 @@ void MachineInstr::print(raw_ostream &OS, const TargetMachine *TM,
     // call instructions much less noisy on targets where calls clobber lots
     // of registers. Don't rely on MO.isDead() because we may be called before
     // LiveVariables is run, or we may be looking at a non-allocatable reg.
-    if (MF && isCall() &&
+    if (MRI && isCall() &&
         MO.isReg() && MO.isImplicit() && MO.isDef()) {
       unsigned Reg = MO.getReg();
       if (TargetRegisterInfo::isPhysicalRegister(Reg)) {
-        const MachineRegisterInfo &MRI = MF->getRegInfo();
-        if (MRI.use_empty(Reg)) {
+        if (MRI->use_empty(Reg)) {
           bool HasAliasLive = false;
           for (MCRegAliasIterator AI(
                    Reg, TM->getSubtargetImpl()->getRegisterInfo(), true);
                AI.isValid(); ++AI) {
             unsigned AliasReg = *AI;
-            if (!MRI.use_empty(AliasReg)) {
+            if (!MRI->use_empty(AliasReg)) {
               HasAliasLive = true;
               break;
             }
@@ -1669,13 +1668,12 @@ void MachineInstr::print(raw_ostream &OS, const TargetMachine *TM,
 
       unsigned RCID = 0;
       if (InlineAsm::hasRegClassConstraint(Flag, RCID)) {
-        if (TM)
+        if (TM) {
+          const TargetRegisterInfo *TRI =
+            TM->getSubtargetImpl()->getRegisterInfo();
           OS << ':'
-             << TM->getSubtargetImpl()
-                    ->getRegisterInfo()
-                    ->getRegClass(RCID)
-                    ->getName();
-        else
+             << TRI->getRegClassName(TRI->getRegClass(RCID));
+        } else
           OS << ":RC" << RCID;
       }
 
@@ -1724,7 +1722,8 @@ void MachineInstr::print(raw_ostream &OS, const TargetMachine *TM,
     if (!HaveSemi) OS << ";"; HaveSemi = true;
     for (unsigned i = 0; i != VirtRegs.size(); ++i) {
       const TargetRegisterClass *RC = MRI->getRegClass(VirtRegs[i]);
-      OS << " " << RC->getName() << ':' << PrintReg(VirtRegs[i]);
+      OS << " " << MRI->getTargetRegisterInfo()->getRegClassName(RC)
+         << ':' << PrintReg(VirtRegs[i]);
       for (unsigned j = i+1; j != VirtRegs.size();) {
         if (MRI->getRegClass(VirtRegs[j]) != RC) {
           ++j;

lib/CodeGen/MachineVerifier.cpp

@@ -907,7 +907,7 @@ MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
           if (!DRC->contains(Reg)) {
             report("Illegal physical register for instruction", MO, MONum);
             *OS << TRI->getName(Reg) << " is not a "
-                << DRC->getName() << " register.\n";
+                << TRI->getRegClassName(DRC) << " register.\n";
           }
         }
       } else {
@@ -918,13 +918,13 @@ MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
             TRI->getSubClassWithSubReg(RC, SubIdx);
           if (!SRC) {
             report("Invalid subregister index for virtual register", MO, MONum);
-            *OS << "Register class " << RC->getName()
+            *OS << "Register class " << TRI->getRegClassName(RC)
                 << " does not support subreg index " << SubIdx << "\n";
             return;
           }
           if (RC != SRC) {
             report("Invalid register class for subregister index", MO, MONum);
-            *OS << "Register class " << RC->getName()
+            *OS << "Register class " << TRI->getRegClassName(RC)
                 << " does not fully support subreg index " << SubIdx << "\n";
             return;
           }
@@ -946,8 +946,9 @@ MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
           }
           if (!RC->hasSuperClassEq(DRC)) {
             report("Illegal virtual register for instruction", MO, MONum);
-            *OS << "Expected a " << DRC->getName() << " register, but got a "
-                << RC->getName() << " register\n";
+            *OS << "Expected a " << TRI->getRegClassName(DRC)
+                << " register, but got a " << TRI->getRegClassName(RC)
+                << " register\n";
           }
         }
       }

lib/CodeGen/RegAllocBase.cpp

@@ -101,7 +101,7 @@ void RegAllocBase::allocatePhysRegs() {
     // register if possible and populate a list of new live intervals that
     // result from splitting.
     DEBUG(dbgs() << "\nselectOrSplit "
-          << MRI->getRegClass(VirtReg->reg)->getName()
+          << TRI->getRegClassName(MRI->getRegClass(VirtReg->reg))
           << ':' << *VirtReg << " w=" << VirtReg->weight << '\n');
     typedef SmallVector<unsigned, 4> VirtRegVec;
     VirtRegVec SplitVRegs;

lib/CodeGen/RegAllocFast.cpp

@@ -548,7 +548,7 @@ RAFast::LiveRegMap::iterator RAFast::allocVirtReg(MachineInstr *MI,
   }
 
   DEBUG(dbgs() << "Allocating " << PrintReg(VirtReg) << " from "
-               << RC->getName() << "\n");
+               << TRI->getRegClassName(RC) << "\n");
 
   unsigned BestReg = 0, BestCost = spillImpossible;
   for (ArrayRef<MCPhysReg>::iterator I = AO.begin(), E = AO.end(); I != E; ++I){

lib/CodeGen/RegAllocGreedy.cpp

@@ -817,7 +817,7 @@ unsigned RAGreedy::tryEvict(LiveInterval &VirtReg,
     const TargetRegisterClass *RC = MRI->getRegClass(VirtReg.reg);
     unsigned MinCost = RegClassInfo.getMinCost(RC);
     if (MinCost >= CostPerUseLimit) {
-      DEBUG(dbgs() << RC->getName() << " minimum cost = " << MinCost
+      DEBUG(dbgs() << TRI->getRegClassName(RC) << " minimum cost = " << MinCost
                    << ", no cheaper registers to be found.\n");
       return 0;
     }

lib/CodeGen/RegisterClassInfo.cpp

@@ -137,7 +137,7 @@ void RegisterClassInfo::compute(const TargetRegisterClass *RC) const {
   RCI.LastCostChange = LastCostChange;
 
   DEBUG({
-    dbgs() << "AllocationOrder(" << RC->getName() << ") = [";
+    dbgs() << "AllocationOrder(" << TRI->getRegClassName(RC) << ") = [";
     for (unsigned I = 0; I != RCI.NumRegs; ++I)
       dbgs() << ' ' << PrintReg(RCI.Order[I], TRI);
     dbgs() << (RCI.ProperSubClass ? " ] (sub-class)\n" : " ]\n");

lib/CodeGen/RegisterCoalescer.cpp

@@ -1106,8 +1106,8 @@ bool RegisterCoalescer::joinCopy(MachineInstr *CopyMI, bool &Again) {
     }
   } else {
     DEBUG({
-      dbgs() << "\tConsidering merging to " << CP.getNewRC()->getName()
-             << " with ";
+      dbgs() << "\tConsidering merging to "
+             << TRI->getRegClassName(CP.getNewRC()) << " with ";
       if (CP.getDstIdx() && CP.getSrcIdx())
         dbgs() << PrintReg(CP.getDstReg()) << " in "
                << TRI->getSubRegIndexName(CP.getDstIdx()) << " and "
@@ -2264,7 +2264,7 @@ bool RegisterCoalescer::runOnMachineFunction(MachineFunction &fn) {
       continue;
     if (MRI->recomputeRegClass(Reg, *TM)) {
       DEBUG(dbgs() << PrintReg(Reg) << " inflated to "
-                   << MRI->getRegClass(Reg)->getName() << '\n');
+                   << TRI->getRegClassName(MRI->getRegClass(Reg)) << '\n');
       ++NumInflated;
     }
   }

lib/CodeGen/SelectionDAG/ScheduleDAGRRList.cpp

@@ -1935,8 +1935,8 @@ void RegReductionPQBase::dumpRegPressure() const {
     unsigned Id = RC->getID();
     unsigned RP = RegPressure[Id];
     if (!RP) continue;
-    DEBUG(dbgs() << RC->getName() << ": " << RP << " / " << RegLimit[Id]
-          << '\n');
+    DEBUG(dbgs() << TRI->getRegClassName(RC) << ": " << RP << " / "
+          << RegLimit[Id] << '\n');
   }
 #endif
 }

lib/CodeGen/VirtRegMap.cpp

@@ -124,7 +124,7 @@ void VirtRegMap::print(raw_ostream &OS, const Module*) const {
     if (Virt2PhysMap[Reg] != (unsigned)VirtRegMap::NO_PHYS_REG) {
       OS << '[' << PrintReg(Reg, TRI) << " -> "
          << PrintReg(Virt2PhysMap[Reg], TRI) << "] "
-         << MRI->getRegClass(Reg)->getName() << "\n";
+         << TRI->getRegClassName(MRI->getRegClass(Reg)) << "\n";
     }
   }
 
@@ -132,7 +132,7 @@ void VirtRegMap::print(raw_ostream &OS, const Module*) const {
     unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
     if (Virt2StackSlotMap[Reg] != VirtRegMap::NO_STACK_SLOT) {
       OS << '[' << PrintReg(Reg, TRI) << " -> fi#" << Virt2StackSlotMap[Reg]
-         << "] " << MRI->getRegClass(Reg)->getName() << "\n";
+         << "] " << TRI->getRegClassName(MRI->getRegClass(Reg)) << "\n";
     }
   }
   OS << '\n';

utils/TableGen/RegisterInfoEmitter.cpp

@@ -848,6 +848,8 @@ RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
   // Loop over all of the register classes... emitting each one.
   OS << "namespace {     // Register classes...\n";
 
+  SequenceToOffsetTable<std::string> RegClassStrings;
+
   // Emit the register enum value arrays for each RegisterClass
   for (unsigned rc = 0, e = RegisterClasses.size(); rc != e; ++rc) {
     const CodeGenRegisterClass &RC = *RegisterClasses[rc];
@@ -856,6 +858,8 @@ RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
     // Give the register class a legal C name if it's anonymous.
     std::string Name = RC.getName();
 
+    RegClassStrings.add(Name);
+
     // Emit the register list now.
     OS << "  // " << Name << " Register Class...\n"
        << "  const MCPhysReg " << Name
@@ -880,6 +884,11 @@ RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
   }
   OS << "}\n\n";
 
+  RegClassStrings.layout();
+  OS << "extern const char " << TargetName << "RegClassStrings[] = {\n";
+  RegClassStrings.emit(OS, printChar);
+  OS << "};\n\n";
+
   OS << "extern const MCRegisterClass " << TargetName
      << "MCRegisterClasses[] = {\n";
 
@@ -892,8 +901,8 @@ RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
     assert((RC.SpillAlignment/8) <= 0xffff && "SpillAlignment too large.");
     assert(RC.CopyCost >= -128 && RC.CopyCost <= 127 && "Copy cost too large.");
 
-    OS << "  { " << '\"' << RC.getName() << "\", "
-       << RC.getName() << ", " << RC.getName() << "Bits, "
+    OS << "  { " << RC.getName() << ", " << RC.getName() << "Bits, "
+       << RegClassStrings.get(RC.getName()) << ", "
        << RC.getOrder().size() << ", sizeof(" << RC.getName() << "Bits), "
        << RC.getQualifiedName() + "RegClassID" << ", "
        << RC.SpillSize/8 << ", "
@@ -934,6 +943,7 @@ RegisterInfoEmitter::runMCDesc(raw_ostream &OS, CodeGenTarget &Target,
      << RegBank.getNumNativeRegUnits() << ", "
      << TargetName << "RegDiffLists, "
      << TargetName << "RegStrings, "
+     << TargetName << "RegClassStrings, "
      << TargetName << "SubRegIdxLists, "
      << (SubRegIndices.size() + 1) << ",\n"
      << TargetName << "SubRegIdxRanges, "
@@ -1267,6 +1277,7 @@ RegisterInfoEmitter::runTargetDesc(raw_ostream &OS, CodeGenTarget &Target,
   OS << "extern const MCRegisterDesc " << TargetName << "RegDesc[];\n";
   OS << "extern const MCPhysReg " << TargetName << "RegDiffLists[];\n";
   OS << "extern const char " << TargetName << "RegStrings[];\n";
+  OS << "extern const char " << TargetName << "RegClassStrings[];\n";
   OS << "extern const MCPhysReg " << TargetName << "RegUnitRoots[][2];\n";
   OS << "extern const uint16_t " << TargetName << "SubRegIdxLists[];\n";
   OS << "extern const MCRegisterInfo::SubRegCoveredBits "
@@ -1289,6 +1300,7 @@ RegisterInfoEmitter::runTargetDesc(raw_ostream &OS, CodeGenTarget &Target,
      << "                     " << RegBank.getNumNativeRegUnits() << ",\n"
      << "                     " << TargetName << "RegDiffLists,\n"
      << "                     " << TargetName << "RegStrings,\n"
+     << "                     " << TargetName << "RegClassStrings,\n"
      << "                     " << TargetName << "SubRegIdxLists,\n"
      << "                     " << SubRegIndices.size() + 1 << ",\n"
      << "                     " << TargetName << "SubRegIdxRanges,\n"