class LiveInterval;
class LiveIntervalAnalysis;
-class MachineRegisterInfo;
class TargetRegisterInfo;
class VirtRegMap;
class LiveRegMatrix : public MachineFunctionPass {
const TargetRegisterInfo *TRI;
- MachineRegisterInfo *MRI;
LiveIntervals *LIS;
VirtRegMap *VRM;
return MO->Contents.Reg.Next;
}
- /// UsedRegUnits - This is a bit vector that is computed and set by the
- /// register allocator, and must be kept up to date by passes that run after
- /// register allocation (though most don't modify this). This is used
- /// so that the code generator knows which callee save registers to save and
- /// for other target specific uses.
- /// This vector has bits set for register units that are modified in the
- /// current function. It doesn't include registers clobbered by function
- /// calls with register mask operands.
- BitVector UsedRegUnits;
-
/// UsedPhysRegMask - Additional used physregs including aliases.
/// This bit vector represents all the registers clobbered by function calls.
- /// It can model things that UsedRegUnits can't, such as function calls that
- /// clobber ymm7 but preserve the low half in xmm7.
BitVector UsedPhysRegMask;
/// ReservedRegs - This is a bit vector of reserved registers. The target
/// ignored.
bool isPhysRegModified(unsigned PhysReg) const;
- //===--------------------------------------------------------------------===//
- // Physical Register Use Info
- //===--------------------------------------------------------------------===//
-
- /// isPhysRegUsed - Return true if the specified register is used in this
- /// function. Also check for clobbered aliases and registers clobbered by
- /// function calls with register mask operands.
- ///
- /// This only works after register allocation.
- bool isPhysRegUsed(unsigned Reg) const {
- if (UsedPhysRegMask.test(Reg))
- return true;
- for (MCRegUnitIterator Units(Reg, getTargetRegisterInfo());
- Units.isValid(); ++Units)
- if (UsedRegUnits.test(*Units))
- return true;
- return false;
- }
-
- /// Mark the specified register unit as used in this function.
- /// This should only be called during and after register allocation.
- void setRegUnitUsed(unsigned RegUnit) {
- UsedRegUnits.set(RegUnit);
- }
-
- /// setPhysRegUsed - Mark the specified register used in this function.
- /// This should only be called during and after register allocation.
- void setPhysRegUsed(unsigned Reg) {
- for (MCRegUnitIterator Units(Reg, getTargetRegisterInfo());
- Units.isValid(); ++Units)
- UsedRegUnits.set(*Units);
- }
-
/// addPhysRegsUsedFromRegMask - Mark any registers not in RegMask as used.
/// This corresponds to the bit mask attached to register mask operands.
void addPhysRegsUsedFromRegMask(const uint32_t *RegMask) {
UsedPhysRegMask.setBitsNotInMask(RegMask);
}
- /// setPhysRegUnused - Mark the specified register unused in this function.
- /// This should only be called during and after register allocation.
- void setPhysRegUnused(unsigned Reg) {
- UsedPhysRegMask.reset(Reg);
- for (MCRegUnitIterator Units(Reg, getTargetRegisterInfo());
- Units.isValid(); ++Units)
- UsedRegUnits.reset(*Units);
- }
-
-
//===--------------------------------------------------------------------===//
// Reserved Register Info
//===--------------------------------------------------------------------===//
// If no relevant registers are used in the function, we can skip it
// completely.
bool anyregs = false;
+ const MachineRegisterInfo &MRI = mf.getRegInfo();
for (TargetRegisterClass::const_iterator I = RC->begin(), E = RC->end();
- I != E; ++I)
- if (MF->getRegInfo().isPhysRegUsed(*I)) {
- anyregs = true;
- break;
- }
+ I != E && !anyregs; ++I)
+ for (MCRegAliasIterator AI(*I, TRI, true); AI.isValid(); ++AI)
+ if (!MRI.reg_nodbg_empty(*AI)) {
+ anyregs = true;
+ break;
+ }
if (!anyregs) return false;
// Initialize the AliasMap on the first use.
#include "RegisterCoalescer.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
-#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/VirtRegMap.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;
bool LiveRegMatrix::runOnMachineFunction(MachineFunction &MF) {
TRI = MF.getSubtarget().getRegisterInfo();
- MRI = &MF.getRegInfo();
LIS = &getAnalysis<LiveIntervals>();
VRM = &getAnalysis<VirtRegMap>();
<< " to " << PrintReg(PhysReg, TRI) << ':');
assert(!VRM->hasPhys(VirtReg.reg) && "Duplicate VirtReg assignment");
VRM->assignVirt2Phys(VirtReg.reg, PhysReg);
- MRI->setPhysRegUsed(PhysReg);
foreachUnit(TRI, VirtReg, PhysReg, [&](unsigned Unit,
const LiveRange &Range) {
TracksSubRegLiveness(false) {
VRegInfo.reserve(256);
RegAllocHints.reserve(256);
- UsedRegUnits.resize(getTargetRegisterInfo()->getNumRegUnits());
UsedPhysRegMask.resize(getTargetRegisterInfo()->getNumRegs());
// Create the physreg use/def lists.
// Replace this reference to the virtual register with the
// scratch register.
assert (ScratchReg && "Missing scratch register!");
- MachineRegisterInfo &MRI = Fn.getRegInfo();
Fn.getRegInfo().replaceRegWith(Reg, ScratchReg);
- // Make sure MRI now accounts this register as used.
- MRI.setPhysRegUsed(ScratchReg);
-
// Because this instruction was processed by the RS before this
// register was allocated, make sure that the RS now records the
// register as being used.
}
}
- for (UsedInInstrSet::iterator
- I = UsedInInstr.begin(), E = UsedInInstr.end(); I != E; ++I)
- MRI->setRegUnitUsed(*I);
-
// Track registers defined by instruction - early clobbers and tied uses at
// this point.
UsedInInstr.clear();
killVirtReg(VirtDead[i]);
VirtDead.clear();
- for (UsedInInstrSet::iterator
- I = UsedInInstr.begin(), E = UsedInInstr.end(); I != E; ++I)
- MRI->setRegUnitUsed(*I);
-
if (CopyDst && CopyDst == CopySrc && CopyDstSub == CopySrcSub) {
DEBUG(dbgs() << "-- coalescing: " << *MI);
Coalesced.push_back(MI);
AllocateBasicBlock();
}
- // Add the clobber lists for all the instructions we skipped earlier.
- for (const MCInstrDesc *Desc : SkippedInstrs)
- if (const uint16_t *Defs = Desc->getImplicitDefs())
- while (*Defs)
- MRI->setPhysRegUsed(*Defs++);
-
// All machine operands and other references to virtual registers have been
// replaced. Remove the virtual registers.
MRI->clearVirtRegs();
SlotIndexes *Indexes;
LiveIntervals *LIS;
VirtRegMap *VRM;
- SparseSet<unsigned> PhysRegs;
void rewrite();
void addMBBLiveIns();
SmallVector<unsigned, 8> SuperDeads;
SmallVector<unsigned, 8> SuperDefs;
SmallVector<unsigned, 8> SuperKills;
- SmallPtrSet<const MachineInstr *, 4> NoReturnInsts;
-
- // Here we have a SparseSet to hold which PhysRegs are actually encountered
- // in the MF we are about to iterate over so that later when we call
- // setPhysRegUsed, we are only doing it for physRegs that were actually found
- // in the program and not for all of the possible physRegs for the given
- // target architecture. If the target has a lot of physRegs, then for a small
- // program there will be a significant compile time reduction here.
- PhysRegs.clear();
- PhysRegs.setUniverse(TRI->getNumRegs());
-
- // The function with uwtable should guarantee that the stack unwinder
- // can unwind the stack to the previous frame. Thus, we can't apply the
- // noreturn optimization if the caller function has uwtable attribute.
- bool HasUWTable = MF->getFunction()->hasFnAttribute(Attribute::UWTable);
for (MachineFunction::iterator MBBI = MF->begin(), MBBE = MF->end();
MBBI != MBBE; ++MBBI) {
DEBUG(MBBI->print(dbgs(), Indexes));
- bool IsExitBB = MBBI->succ_empty();
for (MachineBasicBlock::instr_iterator
MII = MBBI->instr_begin(), MIE = MBBI->instr_end(); MII != MIE;) {
MachineInstr *MI = MII;
++MII;
- // Check if this instruction is a call to a noreturn function. If this
- // is a call to noreturn function and we don't need the stack unwinding
- // functionality (i.e. this function does not have uwtable attribute and
- // the callee function has the nounwind attribute), then we can ignore
- // the definitions set by this instruction.
- if (!HasUWTable && IsExitBB && MI->isCall()) {
- for (MachineInstr::mop_iterator MOI = MI->operands_begin(),
- MOE = MI->operands_end(); MOI != MOE; ++MOI) {
- MachineOperand &MO = *MOI;
- if (!MO.isGlobal())
- continue;
- const Function *Func = dyn_cast<Function>(MO.getGlobal());
- if (!Func || !Func->hasFnAttribute(Attribute::NoReturn) ||
- // We need to keep correct unwind information
- // even if the function will not return, since the
- // runtime may need it.
- !Func->hasFnAttribute(Attribute::NoUnwind))
- continue;
- NoReturnInsts.insert(MI);
- break;
- }
- }
-
for (MachineInstr::mop_iterator MOI = MI->operands_begin(),
MOE = MI->operands_end(); MOI != MOE; ++MOI) {
MachineOperand &MO = *MOI;
if (MO.isRegMask())
MRI->addPhysRegsUsedFromRegMask(MO.getRegMask());
- // If we encounter a VirtReg or PhysReg then get at the PhysReg and add
- // it to the physreg bitset. Later we use only the PhysRegs that were
- // actually encountered in the MF to populate the MRI's used physregs.
- if (MO.isReg() && MO.getReg())
- PhysRegs.insert(
- TargetRegisterInfo::isVirtualRegister(MO.getReg()) ?
- VRM->getPhys(MO.getReg()) :
- MO.getReg());
-
if (!MO.isReg() || !TargetRegisterInfo::isVirtualRegister(MO.getReg()))
continue;
unsigned VirtReg = MO.getReg();
}
}
}
-
- // Tell MRI about physical registers in use.
- if (NoReturnInsts.empty()) {
- for (SparseSet<unsigned>::iterator
- RegI = PhysRegs.begin(), E = PhysRegs.end(); RegI != E; ++RegI)
- if (!MRI->reg_nodbg_empty(*RegI))
- MRI->setPhysRegUsed(*RegI);
- } else {
- for (SparseSet<unsigned>::iterator
- I = PhysRegs.begin(), E = PhysRegs.end(); I != E; ++I) {
- unsigned Reg = *I;
- if (MRI->reg_nodbg_empty(Reg))
- continue;
- // Check if this register has a use that will impact the rest of the
- // code. Uses in debug and noreturn instructions do not impact the
- // generated code.
- for (MachineInstr &It : MRI->reg_nodbg_instructions(Reg)) {
- if (!NoReturnInsts.count(&It)) {
- MRI->setPhysRegUsed(Reg);
- break;
- }
- }
- }
- }
}
if (Change) {
Substs[MO.getReg()] = Reg;
MO.setReg(Reg);
- MRI->setPhysRegUsed(Reg);
Changed = true;
}
if (NumBytes && NeedsRealignment) {
// Use the first callee-saved register as a scratch register.
scratchSPReg = AArch64::X9;
- MF.getRegInfo().setPhysRegUsed(scratchSPReg);
}
// If we're a leaf function, try using the red zone.
if (!LaneVGPRs.count(LaneVGPRIdx)) {
unsigned LaneVGPR = TRI->findUnusedRegister(MRI, &AMDGPU::VGPR_32RegClass);
LaneVGPRs[LaneVGPRIdx] = LaneVGPR;
- MRI.setPhysRegUsed(LaneVGPR);
// Add this register as live-in to all blocks to avoid machine verifer
// complaining about use of an undefined physical register.
if (ScratchOffsetReg != AMDGPU::NoRegister) {
// Found an SGPR to use
- MRI.setPhysRegUsed(ScratchOffsetReg);
BuildMI(*Entry, I, DL, TII->get(AMDGPU::S_MOV_B32), ScratchOffsetReg)
.addReg(ScratchOffsetPreloadReg);
} else {
for (TargetRegisterClass::iterator I = RC->begin(), E = RC->end();
I != E; ++I) {
- if (!MRI.isPhysRegUsed(*I))
+ if (MRI.reg_nodbg_empty(*I))
return *I;
}
return AMDGPU::NoRegister;
// Check for an unused caller-saved register.
for ( ; *CallerSavedRegs; ++CallerSavedRegs) {
MCPhysReg FreeReg = *CallerSavedRegs;
- if (MRI.isPhysRegUsed(FreeReg))
+ if (!MRI.reg_nodbg_empty(FreeReg))
continue;
// Check aliased register usage.
bool IsCurrentRegUsed = false;
for (MCRegAliasIterator AI(FreeReg, &HRI, false); AI.isValid(); ++AI)
- if (MRI.isPhysRegUsed(*AI)) {
+ if (!MRI.reg_nodbg_empty(*AI)) {
IsCurrentRegUsed = true;
break;
}
const TargetRegisterInfo *TRI = MF->getSubtarget().getRegisterInfo();
DebugLoc dl = MI->getDebugLoc();
+ const MachineRegisterInfo &MRI = MF->getRegInfo();
unsigned UsedRegMask = 0;
for (unsigned i = 0; i != 32; ++i)
- if (MF->getRegInfo().isPhysRegUsed(VRRegNo[i]))
+ if (MRI.isPhysRegModified(VRRegNo[i]))
UsedRegMask |= 1 << (31-i);
// Live in and live out values already must be in the mask, so don't bother
{
for (unsigned reg = SP::I0; reg <= SP::I7; ++reg)
- if (MRI->isPhysRegUsed(reg))
+ if (!MRI->reg_nodbg_empty(reg))
return false;
for (unsigned reg = SP::L0; reg <= SP::L7; ++reg)
- if (MRI->isPhysRegUsed(reg))
+ if (!MRI->reg_nodbg_empty(reg))
return false;
return true;
MachineRegisterInfo &MRI = MF.getRegInfo();
MachineFrameInfo *MFI = MF.getFrameInfo();
- return !(MFI->hasCalls() // has calls
- || MRI.isPhysRegUsed(SP::L0) // Too many registers needed
- || MRI.isPhysRegUsed(SP::O6) // %SP is used
- || hasFP(MF)); // need %FP
+ return !(MFI->hasCalls() // has calls
+ || !MRI.reg_nodbg_empty(SP::L0) // Too many registers needed
+ || !MRI.reg_nodbg_empty(SP::O6) // %SP is used
+ || hasFP(MF)); // need %FP
}
void SparcFrameLowering::remapRegsForLeafProc(MachineFunction &MF) const {
// Remap %i[0-7] to %o[0-7].
for (unsigned reg = SP::I0; reg <= SP::I7; ++reg) {
- if (!MRI.isPhysRegUsed(reg))
+ if (MRI.reg_nodbg_empty(reg))
continue;
unsigned mapped_reg = (reg - SP::I0 + SP::O0);
- assert(!MRI.isPhysRegUsed(mapped_reg));
+ assert(MRI.reg_nodbg_empty(mapped_reg));
// Replace I register with O register.
MRI.replaceRegWith(reg, mapped_reg);
-
- // Mark the reg unused.
- MRI.setPhysRegUnused(reg);
}
// Rewrite MBB's Live-ins.
bool FPIsUsed = false;
static_assert(X86::FP6 == X86::FP0+6, "Register enums aren't sorted right!");
+ const MachineRegisterInfo &MRI = MF.getRegInfo();
for (unsigned i = 0; i <= 6; ++i)
- if (MF.getRegInfo().isPhysRegUsed(X86::FP0+i)) {
+ if (!MRI.reg_nodbg_empty(X86::FP0 + i)) {
FPIsUsed = true;
break;
}
.addImm(StackSize);
BuildMI(allocMBB, DL, TII.get(MOVri), Reg11)
.addImm(X86FI->getArgumentStackSize());
- MF.getRegInfo().setPhysRegUsed(Reg10);
- MF.getRegInfo().setPhysRegUsed(Reg11);
} else {
BuildMI(allocMBB, DL, TII.get(X86::PUSHi32))
.addImm(X86FI->getArgumentStackSize());