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-rw-r--r--lib/CodeGen/RegAllocFast.cpp68
1 files changed, 48 insertions, 20 deletions
diff --git a/lib/CodeGen/RegAllocFast.cpp b/lib/CodeGen/RegAllocFast.cpp
index fc150d55e226..15036e38b893 100644
--- a/lib/CodeGen/RegAllocFast.cpp
+++ b/lib/CodeGen/RegAllocFast.cpp
@@ -48,7 +48,10 @@ namespace {
public:
static char ID;
RAFast() : MachineFunctionPass(ID), StackSlotForVirtReg(-1),
- isBulkSpilling(false) {}
+ isBulkSpilling(false) {
+ initializePHIEliminationPass(*PassRegistry::getPassRegistry());
+ initializeTwoAddressInstructionPassPass(*PassRegistry::getPassRegistry());
+ }
private:
const TargetMachine *TM;
MachineFunction *MF;
@@ -259,8 +262,8 @@ void RAFast::spillVirtReg(MachineBasicBlock::iterator MI,
// instruction, not on the spill.
bool SpillKill = LR.LastUse != MI;
LR.Dirty = false;
- DEBUG(dbgs() << "Spilling %reg" << LRI->first
- << " in " << TRI->getName(LR.PhysReg));
+ DEBUG(dbgs() << "Spilling " << PrintReg(LRI->first, TRI)
+ << " in " << PrintReg(LR.PhysReg, TRI));
const TargetRegisterClass *RC = MRI->getRegClass(LRI->first);
int FI = getStackSpaceFor(LRI->first, RC);
DEBUG(dbgs() << " to stack slot #" << FI << "\n");
@@ -331,7 +334,7 @@ void RAFast::usePhysReg(MachineOperand &MO) {
MO.setIsKill();
return;
default:
- // The physreg was allocated to a virtual register. That means to value we
+ // The physreg was allocated to a virtual register. That means the value we
// wanted has been clobbered.
llvm_unreachable("Instruction uses an allocated register");
}
@@ -458,8 +461,8 @@ unsigned RAFast::calcSpillCost(unsigned PhysReg) const {
/// register must not be used for anything else when this is called.
///
void RAFast::assignVirtToPhysReg(LiveRegEntry &LRE, unsigned PhysReg) {
- DEBUG(dbgs() << "Assigning %reg" << LRE.first << " to "
- << TRI->getName(PhysReg) << "\n");
+ DEBUG(dbgs() << "Assigning " << PrintReg(LRE.first, TRI) << " to "
+ << PrintReg(PhysReg, TRI) << "\n");
PhysRegState[PhysReg] = LRE.first;
assert(!LRE.second.PhysReg && "Already assigned a physreg");
LRE.second.PhysReg = PhysReg;
@@ -503,8 +506,8 @@ void RAFast::allocVirtReg(MachineInstr *MI, LiveRegEntry &LRE, unsigned Hint) {
return assignVirtToPhysReg(LRE, PhysReg);
}
- DEBUG(dbgs() << "Allocating %reg" << VirtReg << " from " << RC->getName()
- << "\n");
+ DEBUG(dbgs() << "Allocating " << PrintReg(VirtReg) << " from "
+ << RC->getName() << "\n");
unsigned BestReg = 0, BestCost = spillImpossible;
for (TargetRegisterClass::iterator I = AOB; I != AOE; ++I) {
@@ -584,8 +587,8 @@ RAFast::reloadVirtReg(MachineInstr *MI, unsigned OpNum,
allocVirtReg(MI, *LRI, Hint);
const TargetRegisterClass *RC = MRI->getRegClass(VirtReg);
int FrameIndex = getStackSpaceFor(VirtReg, RC);
- DEBUG(dbgs() << "Reloading %reg" << VirtReg << " into "
- << TRI->getName(LR.PhysReg) << "\n");
+ DEBUG(dbgs() << "Reloading " << PrintReg(VirtReg, TRI) << " into "
+ << PrintReg(LR.PhysReg, TRI) << "\n");
TII->loadRegFromStackSlot(*MBB, MI, LR.PhysReg, FrameIndex, RC, TRI);
++NumLoads;
} else if (LR.Dirty) {
@@ -653,11 +656,12 @@ void RAFast::handleThroughOperands(MachineInstr *MI,
MachineOperand &MO = MI->getOperand(i);
if (!MO.isReg()) continue;
unsigned Reg = MO.getReg();
- if (!Reg || TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
+ if (!TargetRegisterInfo::isVirtualRegister(Reg))
+ continue;
if (MO.isEarlyClobber() || MI->isRegTiedToDefOperand(i) ||
(MO.getSubReg() && MI->readsVirtualRegister(Reg))) {
if (ThroughRegs.insert(Reg))
- DEBUG(dbgs() << " %reg" << Reg);
+ DEBUG(dbgs() << ' ' << PrintReg(Reg));
}
}
@@ -685,7 +689,7 @@ void RAFast::handleThroughOperands(MachineInstr *MI,
MachineOperand &MO = MI->getOperand(i);
if (!MO.isReg()) continue;
unsigned Reg = MO.getReg();
- if (!Reg || TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
+ if (!TargetRegisterInfo::isVirtualRegister(Reg)) continue;
if (MO.isUse()) {
unsigned DefIdx = 0;
if (!MI->isRegTiedToDefOperand(i, &DefIdx)) continue;
@@ -731,6 +735,27 @@ void RAFast::handleThroughOperands(MachineInstr *MI,
void RAFast::AllocateBasicBlock() {
DEBUG(dbgs() << "\nAllocating " << *MBB);
+ // FIXME: This should probably be added by instruction selection instead?
+ // If the last instruction in the block is a return, make sure to mark it as
+ // using all of the live-out values in the function. Things marked both call
+ // and return are tail calls; do not do this for them. The tail callee need
+ // not take the same registers as input that it produces as output, and there
+ // are dependencies for its input registers elsewhere.
+ if (!MBB->empty() && MBB->back().getDesc().isReturn() &&
+ !MBB->back().getDesc().isCall()) {
+ MachineInstr *Ret = &MBB->back();
+
+ for (MachineRegisterInfo::liveout_iterator
+ I = MF->getRegInfo().liveout_begin(),
+ E = MF->getRegInfo().liveout_end(); I != E; ++I) {
+ assert(TargetRegisterInfo::isPhysicalRegister(*I) &&
+ "Cannot have a live-out virtual register.");
+
+ // Add live-out registers as implicit uses.
+ Ret->addRegisterKilled(*I, TRI, true);
+ }
+ }
+
PhysRegState.assign(TRI->getNumRegs(), regDisabled);
assert(LiveVirtRegs.empty() && "Mapping not cleared form last block?");
@@ -761,7 +786,7 @@ void RAFast::AllocateBasicBlock() {
dbgs() << "*";
break;
default:
- dbgs() << "=%reg" << PhysRegState[Reg];
+ dbgs() << '=' << PrintReg(PhysRegState[Reg]);
if (LiveVirtRegs[PhysRegState[Reg]].Dirty)
dbgs() << "*";
assert(LiveVirtRegs[PhysRegState[Reg]].PhysReg == Reg &&
@@ -791,16 +816,18 @@ void RAFast::AllocateBasicBlock() {
MachineOperand &MO = MI->getOperand(i);
if (!MO.isReg()) continue;
unsigned Reg = MO.getReg();
- if (!Reg || TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
+ if (!TargetRegisterInfo::isVirtualRegister(Reg)) continue;
LiveDbgValueMap[Reg] = MI;
LiveRegMap::iterator LRI = LiveVirtRegs.find(Reg);
if (LRI != LiveVirtRegs.end())
setPhysReg(MI, i, LRI->second.PhysReg);
else {
int SS = StackSlotForVirtReg[Reg];
- if (SS == -1)
+ if (SS == -1) {
// We can't allocate a physreg for a DebugValue, sorry!
+ DEBUG(dbgs() << "Unable to allocate vreg used by DBG_VALUE");
MO.setReg(0);
+ }
else {
// Modify DBG_VALUE now that the value is in a spill slot.
int64_t Offset = MI->getOperand(1).getImm();
@@ -817,9 +844,11 @@ void RAFast::AllocateBasicBlock() {
MI = NewDV;
ScanDbgValue = true;
break;
- } else
+ } else {
// We can't allocate a physreg for a DebugValue; sorry!
+ DEBUG(dbgs() << "Unable to allocate vreg used by DBG_VALUE");
MO.setReg(0);
+ }
}
}
}
@@ -902,7 +931,7 @@ void RAFast::AllocateBasicBlock() {
MachineOperand &MO = MI->getOperand(i);
if (!MO.isReg()) continue;
unsigned Reg = MO.getReg();
- if (!Reg || TargetRegisterInfo::isPhysicalRegister(Reg)) continue;
+ if (!TargetRegisterInfo::isVirtualRegister(Reg)) continue;
if (MO.isUse()) {
LiveRegMap::iterator LRI = reloadVirtReg(MI, i, Reg, CopyDst);
unsigned PhysReg = LRI->second.PhysReg;
@@ -1017,8 +1046,7 @@ bool RAFast::runOnMachineFunction(MachineFunction &Fn) {
// initialize the virtual->physical register map to have a 'null'
// mapping for all virtual registers
- unsigned LastVirtReg = MRI->getLastVirtReg();
- StackSlotForVirtReg.grow(LastVirtReg);
+ StackSlotForVirtReg.resize(MRI->getNumVirtRegs());
// Loop over all of the basic blocks, eliminating virtual register references
for (MachineFunction::iterator MBBi = Fn.begin(), MBBe = Fn.end();
generated by cgit v1.2.3 (git 2.25.1) at 2024-10-27 01:37:36 +0000