RegisterPressureTracker: unify virtual registers and physical regunits.

Now that live register units are tracked individually, the code can be simplified.

llvm-svn: 169426
This commit is contained in:
Andrew Trick 2012-12-05 21:37:47 +00:00
parent 7f7cee39ab
commit 7bbcad7bcd
3 changed files with 226 additions and 261 deletions

View File

@ -347,6 +347,10 @@ namespace llvm {
return RegUnitIntervals[Unit];
}
const LiveInterval *getCachedRegUnit(unsigned Unit) const {
return RegUnitIntervals[Unit];
}
private:
/// computeIntervals - Compute live intervals.
void computeIntervals();

View File

@ -22,6 +22,7 @@
namespace llvm {
class LiveIntervals;
class LiveInterval;
class RegisterClassInfo;
class MachineInstr;
@ -37,17 +38,17 @@ struct RegisterPressure {
/// Increase register pressure for each pressure set impacted by this register
/// class. Normally called by RegPressureTracker, but may be called manually
/// to account for live through (global liveness).
void increase(const TargetRegisterClass *RC, const TargetRegisterInfo *TRI);
/// Increase pressure for each pressure set impacted by this register unit.
void increase(unsigned RU, const TargetRegisterInfo *TRI);
///
/// \param Reg is either a virtual register number or register unit number.
void increase(unsigned Reg, const TargetRegisterInfo *TRI,
const MachineRegisterInfo *MRI);
/// Decrease register pressure for each pressure set impacted by this register
/// class. This is only useful to account for spilling or rematerialization.
void decrease(const TargetRegisterClass *RC, const TargetRegisterInfo *TRI);
/// Decrease pressure for each pressure set impacted by this register unit.
void decrease(unsigned RU, const TargetRegisterInfo *TRI);
///
/// \param Reg is either a virtual register number or register unit number.
void decrease(unsigned Reg, const TargetRegisterInfo *TRI,
const MachineRegisterInfo *MRI);
void dump(const TargetRegisterInfo *TRI) const;
};
@ -122,6 +123,33 @@ struct RegPressureDelta {
RegPressureDelta() {}
};
/// \brief A set of live virtual registers and physical register units.
///
/// Virtual and physical register numbers require separate sparse sets, but most
/// of the RegisterPressureTracker handles them uniformly.
struct LiveRegSet {
SparseSet<unsigned> PhysRegs;
SparseSet<unsigned, VirtReg2IndexFunctor> VirtRegs;
bool contains(unsigned Reg) {
if (TargetRegisterInfo::isVirtualRegister(Reg))
return VirtRegs.count(Reg);
return PhysRegs.count(Reg);
}
bool insert(unsigned Reg) {
if (TargetRegisterInfo::isVirtualRegister(Reg))
return VirtRegs.insert(Reg).second;
return PhysRegs.insert(Reg).second;
}
bool erase(unsigned Reg) {
if (TargetRegisterInfo::isVirtualRegister(Reg))
return VirtRegs.erase(Reg);
return PhysRegs.erase(Reg);
}
};
/// Track the current register pressure at some position in the instruction
/// stream, and remember the high water mark within the region traversed. This
/// does not automatically consider live-through ranges. The client may
@ -163,9 +191,8 @@ class RegPressureTracker {
/// Pressure map indexed by pressure set ID, not class ID.
std::vector<unsigned> CurrSetPressure;
/// List of live registers.
SparseSet<unsigned> LivePhysRegs;
SparseSet<unsigned, VirtReg2IndexFunctor> LiveVirtRegs;
/// Set of live registers.
LiveRegSet LiveRegs;
public:
RegPressureTracker(IntervalPressure &rp) :
@ -215,11 +242,8 @@ public:
/// than the pressure across the traversed region.
std::vector<unsigned> &getRegSetPressureAtPos() { return CurrSetPressure; }
void discoverPhysLiveIn(unsigned Reg);
void discoverPhysLiveOut(unsigned Reg);
void discoverVirtLiveIn(unsigned Reg);
void discoverVirtLiveOut(unsigned Reg);
void discoverLiveOut(unsigned Reg);
void discoverLiveIn(unsigned Reg);
bool isTopClosed() const;
bool isBottomClosed() const;
@ -283,11 +307,10 @@ public:
void dump(const TargetRegisterInfo *TRI) const;
protected:
void increasePhysRegPressure(ArrayRef<unsigned> Regs);
void decreasePhysRegPressure(ArrayRef<unsigned> Regs);
const LiveInterval *getInterval(unsigned Reg) const;
void increaseVirtRegPressure(ArrayRef<unsigned> Regs);
void decreaseVirtRegPressure(ArrayRef<unsigned> Regs);
void increaseRegPressure(ArrayRef<unsigned> Regs);
void decreaseRegPressure(ArrayRef<unsigned> Regs);
void bumpUpwardPressure(const MachineInstr *MI);
void bumpDownwardPressure(const MachineInstr *MI);

View File

@ -46,31 +46,33 @@ static void decreaseSetPressure(std::vector<unsigned> &CurrSetPressure,
}
/// Directly increase pressure only within this RegisterPressure result.
void RegisterPressure::increase(const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) {
increaseSetPressure(MaxSetPressure, MaxSetPressure,
TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
}
/// Directly increase pressure only within this RegisterPressure result.
void RegisterPressure::increase(unsigned RU, const TargetRegisterInfo *TRI) {
increaseSetPressure(MaxSetPressure, MaxSetPressure,
TRI->getRegUnitPressureSets(RU),
TRI->getRegUnitWeight(RU));
void RegisterPressure::increase(unsigned Reg, const TargetRegisterInfo *TRI,
const MachineRegisterInfo *MRI) {
if (TargetRegisterInfo::isVirtualRegister(Reg)) {
const TargetRegisterClass *RC = MRI->getRegClass(Reg);
increaseSetPressure(MaxSetPressure, MaxSetPressure,
TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
}
else {
increaseSetPressure(MaxSetPressure, MaxSetPressure,
TRI->getRegUnitPressureSets(Reg),
TRI->getRegUnitWeight(Reg));
}
}
/// Directly decrease pressure only within this RegisterPressure result.
void RegisterPressure::decrease(const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) {
decreaseSetPressure(MaxSetPressure, TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
}
/// Directly decrease pressure only within this RegisterPressure result.
void RegisterPressure::decrease(unsigned RU, const TargetRegisterInfo *TRI) {
decreaseSetPressure(MaxSetPressure, TRI->getRegUnitPressureSets(RU),
TRI->getRegUnitWeight(RU));
void RegisterPressure::decrease(unsigned Reg, const TargetRegisterInfo *TRI,
const MachineRegisterInfo *MRI) {
if (TargetRegisterInfo::isVirtualRegister(Reg)) {
const TargetRegisterClass *RC = MRI->getRegClass(Reg);
decreaseSetPressure(MaxSetPressure, TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
}
else {
decreaseSetPressure(MaxSetPressure, TRI->getRegUnitPressureSets(Reg),
TRI->getRegUnitWeight(Reg));
}
}
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
@ -102,41 +104,37 @@ void RegPressureTracker::dump(const TargetRegisterInfo *TRI) const {
}
#endif
/// Increase the current pressure as impacted by these register units and bump
/// Increase the current pressure as impacted by these registers and bump
/// the high water mark if needed.
void RegPressureTracker::increasePhysRegPressure(ArrayRef<unsigned> Regs) {
for (unsigned I = 0, E = Regs.size(); I != E; ++I)
increaseSetPressure(CurrSetPressure, P.MaxSetPressure,
TRI->getRegUnitPressureSets(Regs[I]),
TRI->getRegUnitWeight(Regs[I]));
}
/// Simply decrease the current pressure as impacted by these physcial
/// registers.
void RegPressureTracker::decreasePhysRegPressure(ArrayRef<unsigned> Regs) {
for (unsigned I = 0, E = Regs.size(); I != E; ++I)
decreaseSetPressure(CurrSetPressure, TRI->getRegUnitPressureSets(Regs[I]),
TRI->getRegUnitWeight(Regs[I]));
}
/// Increase the current pressure as impacted by these virtual registers and
/// bump the high water mark if needed.
void RegPressureTracker::increaseVirtRegPressure(ArrayRef<unsigned> Regs) {
void RegPressureTracker::increaseRegPressure(ArrayRef<unsigned> Regs) {
for (unsigned I = 0, E = Regs.size(); I != E; ++I) {
const TargetRegisterClass *RC = MRI->getRegClass(Regs[I]);
increaseSetPressure(CurrSetPressure, P.MaxSetPressure,
TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
if (TargetRegisterInfo::isVirtualRegister(Regs[I])) {
const TargetRegisterClass *RC = MRI->getRegClass(Regs[I]);
increaseSetPressure(CurrSetPressure, P.MaxSetPressure,
TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
}
else {
increaseSetPressure(CurrSetPressure, P.MaxSetPressure,
TRI->getRegUnitPressureSets(Regs[I]),
TRI->getRegUnitWeight(Regs[I]));
}
}
}
/// Simply decrease the current pressure as impacted by these virtual registers.
void RegPressureTracker::decreaseVirtRegPressure(ArrayRef<unsigned> Regs) {
/// Simply decrease the current pressure as impacted by these registers.
void RegPressureTracker::decreaseRegPressure(ArrayRef<unsigned> Regs) {
for (unsigned I = 0, E = Regs.size(); I != E; ++I) {
const TargetRegisterClass *RC = MRI->getRegClass(Regs[I]);
decreaseSetPressure(CurrSetPressure,
TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
if (TargetRegisterInfo::isVirtualRegister(Regs[I])) {
const TargetRegisterClass *RC = MRI->getRegClass(Regs[I]);
decreaseSetPressure(CurrSetPressure,
TRI->getRegClassPressureSets(RC),
TRI->getRegClassWeight(RC).RegWeight);
}
else {
decreaseSetPressure(CurrSetPressure, TRI->getRegUnitPressureSets(Regs[I]),
TRI->getRegUnitWeight(Regs[I]));
}
}
}
@ -189,6 +187,12 @@ void RegionPressure::openBottom(MachineBasicBlock::const_iterator PrevBottom) {
LiveInRegs.clear();
}
const LiveInterval *RegPressureTracker::getInterval(unsigned Reg) const {
if (TargetRegisterInfo::isVirtualRegister(Reg))
return &LIS->getInterval(Reg);
return LIS->getCachedRegUnit(Reg);
}
/// Setup the RegPressureTracker.
///
/// TODO: Add support for pressure without LiveIntervals.
@ -218,10 +222,10 @@ void RegPressureTracker::init(const MachineFunction *mf,
static_cast<RegionPressure&>(P).reset();
P.MaxSetPressure = CurrSetPressure;
LivePhysRegs.clear();
LivePhysRegs.setUniverse(TRI->getNumRegs());
LiveVirtRegs.clear();
LiveVirtRegs.setUniverse(MRI->getNumVirtRegs());
LiveRegs.PhysRegs.clear();
LiveRegs.PhysRegs.setUniverse(TRI->getNumRegs());
LiveRegs.VirtRegs.clear();
LiveRegs.VirtRegs.setUniverse(MRI->getNumVirtRegs());
}
/// Does this pressure result have a valid top position and live ins.
@ -258,10 +262,10 @@ void RegPressureTracker::closeTop() {
static_cast<RegionPressure&>(P).TopPos = CurrPos;
assert(P.LiveInRegs.empty() && "inconsistent max pressure result");
P.LiveInRegs.reserve(LivePhysRegs.size() + LiveVirtRegs.size());
P.LiveInRegs.append(LivePhysRegs.begin(), LivePhysRegs.end());
P.LiveInRegs.reserve(LiveRegs.PhysRegs.size() + LiveRegs.VirtRegs.size());
P.LiveInRegs.append(LiveRegs.PhysRegs.begin(), LiveRegs.PhysRegs.end());
for (SparseSet<unsigned>::const_iterator I =
LiveVirtRegs.begin(), E = LiveVirtRegs.end(); I != E; ++I)
LiveRegs.VirtRegs.begin(), E = LiveRegs.VirtRegs.end(); I != E; ++I)
P.LiveInRegs.push_back(*I);
std::sort(P.LiveInRegs.begin(), P.LiveInRegs.end());
P.LiveInRegs.erase(std::unique(P.LiveInRegs.begin(), P.LiveInRegs.end()),
@ -276,10 +280,10 @@ void RegPressureTracker::closeBottom() {
static_cast<RegionPressure&>(P).BottomPos = CurrPos;
assert(P.LiveOutRegs.empty() && "inconsistent max pressure result");
P.LiveOutRegs.reserve(LivePhysRegs.size() + LiveVirtRegs.size());
P.LiveOutRegs.append(LivePhysRegs.begin(), LivePhysRegs.end());
P.LiveOutRegs.reserve(LiveRegs.PhysRegs.size() + LiveRegs.VirtRegs.size());
P.LiveOutRegs.append(LiveRegs.PhysRegs.begin(), LiveRegs.PhysRegs.end());
for (SparseSet<unsigned>::const_iterator I =
LiveVirtRegs.begin(), E = LiveVirtRegs.end(); I != E; ++I)
LiveRegs.VirtRegs.begin(), E = LiveRegs.VirtRegs.end(); I != E; ++I)
P.LiveOutRegs.push_back(*I);
std::sort(P.LiveOutRegs.begin(), P.LiveOutRegs.end());
P.LiveOutRegs.erase(std::unique(P.LiveOutRegs.begin(), P.LiveOutRegs.end()),
@ -289,7 +293,7 @@ void RegPressureTracker::closeBottom() {
/// Finalize the region boundaries and record live ins and live outs.
void RegPressureTracker::closeRegion() {
if (!isTopClosed() && !isBottomClosed()) {
assert(LivePhysRegs.empty() && LiveVirtRegs.empty() &&
assert(LiveRegs.PhysRegs.empty() && LiveRegs.VirtRegs.empty() &&
"no region boundary");
return;
}
@ -307,34 +311,40 @@ static bool containsReg(ArrayRef<unsigned> Regs, unsigned Reg) {
/// Collect this instruction's unique uses and defs into SmallVectors for
/// processing defs and uses in order.
template<bool isVReg>
class RegisterOperands {
const TargetRegisterInfo *TRI;
const MachineRegisterInfo *MRI;
public:
SmallVector<unsigned, 8> Uses;
SmallVector<unsigned, 8> Defs;
SmallVector<unsigned, 8> DeadDefs;
RegisterOperands(const TargetRegisterInfo *tri,
const MachineRegisterInfo *mri): TRI(tri), MRI(mri) {}
/// Push this operand's register onto the correct vector.
void collect(const MachineOperand &MO, const TargetRegisterInfo *TRI) {
void collect(const MachineOperand &MO) {
if (!MO.isReg() || !MO.getReg())
return;
if (MO.readsReg())
pushRegUnits(MO.getReg(), Uses, TRI);
pushRegUnits(MO.getReg(), Uses);
if (MO.isDef()) {
if (MO.isDead())
pushRegUnits(MO.getReg(), DeadDefs, TRI);
pushRegUnits(MO.getReg(), DeadDefs);
else
pushRegUnits(MO.getReg(), Defs, TRI);
pushRegUnits(MO.getReg(), Defs);
}
}
protected:
void pushRegUnits(unsigned Reg, SmallVectorImpl<unsigned> &Regs,
const TargetRegisterInfo *TRI) {
if (isVReg) {
void pushRegUnits(unsigned Reg, SmallVectorImpl<unsigned> &Regs) {
if (TargetRegisterInfo::isVirtualRegister(Reg)) {
if (containsReg(Regs, Reg))
return;
Regs.push_back(Reg);
}
else {
else if (MRI->isAllocatable(Reg)) {
for (MCRegUnitIterator Units(Reg, TRI); Units.isValid(); ++Units) {
if (containsReg(Regs, *Units))
continue;
@ -343,89 +353,49 @@ protected:
}
}
};
typedef RegisterOperands<false> PhysRegOperands;
typedef RegisterOperands<true> VirtRegOperands;
/// Collect physical and virtual register operands.
static void collectOperands(const MachineInstr *MI,
PhysRegOperands &PhysRegOpers,
VirtRegOperands &VirtRegOpers,
const TargetRegisterInfo *TRI,
const MachineRegisterInfo *MRI) {
for(ConstMIBundleOperands OperI(MI); OperI.isValid(); ++OperI) {
const MachineOperand &MO = *OperI;
if (!MO.isReg() || !MO.getReg())
continue;
RegisterOperands &RegOpers) {
for(ConstMIBundleOperands OperI(MI); OperI.isValid(); ++OperI)
RegOpers.collect(*OperI);
if (TargetRegisterInfo::isVirtualRegister(MO.getReg()))
VirtRegOpers.collect(MO, TRI);
else if (MRI->isAllocatable(MO.getReg()))
PhysRegOpers.collect(MO, TRI);
}
// Remove redundant physreg dead defs.
for (unsigned i = PhysRegOpers.DeadDefs.size(); i > 0; --i) {
unsigned Reg = PhysRegOpers.DeadDefs[i-1];
if (containsReg(PhysRegOpers.Defs, Reg))
PhysRegOpers.DeadDefs.erase(&PhysRegOpers.DeadDefs[i-1]);
for (unsigned i = RegOpers.DeadDefs.size(); i > 0; --i) {
unsigned Reg = RegOpers.DeadDefs[i-1];
if (containsReg(RegOpers.Defs, Reg))
RegOpers.DeadDefs.erase(&RegOpers.DeadDefs[i-1]);
}
}
/// Force liveness of registers.
void RegPressureTracker::addLiveRegs(ArrayRef<unsigned> Regs) {
for (unsigned i = 0, e = Regs.size(); i != e; ++i) {
if (TargetRegisterInfo::isVirtualRegister(Regs[i])) {
if (LiveVirtRegs.insert(Regs[i]).second)
increaseVirtRegPressure(Regs[i]);
}
else {
if (LivePhysRegs.insert(Regs[i]).second)
increasePhysRegPressure(Regs[i]);
}
if (LiveRegs.insert(Regs[i]))
increaseRegPressure(Regs[i]);
}
}
/// Add PhysReg to the live in set and increase max pressure.
void RegPressureTracker::discoverPhysLiveIn(unsigned Reg) {
assert(!LivePhysRegs.count(Reg) && "avoid bumping max pressure twice");
/// Add Reg to the live in set and increase max pressure.
void RegPressureTracker::discoverLiveIn(unsigned Reg) {
assert(!LiveRegs.contains(Reg) && "avoid bumping max pressure twice");
if (containsReg(P.LiveInRegs, Reg))
return;
// At live in discovery, unconditionally increase the high water mark.
P.LiveInRegs.push_back(Reg);
P.increase(Reg, TRI);
P.increase(Reg, TRI, MRI);
}
/// Add PhysReg to the live out set and increase max pressure.
void RegPressureTracker::discoverPhysLiveOut(unsigned Reg) {
assert(!LivePhysRegs.count(Reg) && "avoid bumping max pressure twice");
/// Add Reg to the live out set and increase max pressure.
void RegPressureTracker::discoverLiveOut(unsigned Reg) {
assert(!LiveRegs.contains(Reg) && "avoid bumping max pressure twice");
if (containsReg(P.LiveOutRegs, Reg))
return;
// At live out discovery, unconditionally increase the high water mark.
P.LiveOutRegs.push_back(Reg);
P.increase(Reg, TRI);
}
/// Add VirtReg to the live in set and increase max pressure.
void RegPressureTracker::discoverVirtLiveIn(unsigned Reg) {
assert(!LiveVirtRegs.count(Reg) && "avoid bumping max pressure twice");
if (containsReg(P.LiveInRegs, Reg))
return;
// At live in discovery, unconditionally increase the high water mark.
P.LiveInRegs.push_back(Reg);
P.increase(MRI->getRegClass(Reg), TRI);
}
/// Add VirtReg to the live out set and increase max pressure.
void RegPressureTracker::discoverVirtLiveOut(unsigned Reg) {
assert(!LiveVirtRegs.count(Reg) && "avoid bumping max pressure twice");
if (containsReg(P.LiveOutRegs, Reg))
return;
// At live out discovery, unconditionally increase the high water mark.
P.LiveOutRegs.push_back(Reg);
P.increase(MRI->getRegClass(Reg), TRI);
P.increase(Reg, TRI, MRI);
}
/// Recede across the previous instruction.
@ -459,50 +429,35 @@ bool RegPressureTracker::recede() {
if (RequireIntervals && isTopClosed())
static_cast<IntervalPressure&>(P).openTop(SlotIdx);
PhysRegOperands PhysRegOpers;
VirtRegOperands VirtRegOpers;
collectOperands(CurrPos, PhysRegOpers, VirtRegOpers, TRI, MRI);
RegisterOperands RegOpers(TRI, MRI);
collectOperands(CurrPos, RegOpers);
// Boost pressure for all dead defs together.
increasePhysRegPressure(PhysRegOpers.DeadDefs);
increaseVirtRegPressure(VirtRegOpers.DeadDefs);
decreasePhysRegPressure(PhysRegOpers.DeadDefs);
decreaseVirtRegPressure(VirtRegOpers.DeadDefs);
increaseRegPressure(RegOpers.DeadDefs);
decreaseRegPressure(RegOpers.DeadDefs);
// Kill liveness at live defs.
// TODO: consider earlyclobbers?
for (unsigned i = 0, e = PhysRegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Defs[i];
if (LivePhysRegs.erase(Reg))
decreasePhysRegPressure(Reg);
for (unsigned i = 0, e = RegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = RegOpers.Defs[i];
if (LiveRegs.erase(Reg))
decreaseRegPressure(Reg);
else
discoverPhysLiveOut(Reg);
}
for (unsigned i = 0, e = VirtRegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Defs[i];
if (LiveVirtRegs.erase(Reg))
decreaseVirtRegPressure(Reg);
else
discoverVirtLiveOut(Reg);
discoverLiveOut(Reg);
}
// Generate liveness for uses.
for (unsigned i = 0, e = PhysRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Uses[i];
if (LivePhysRegs.insert(Reg).second)
increasePhysRegPressure(Reg);
}
for (unsigned i = 0, e = VirtRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Uses[i];
if (!LiveVirtRegs.count(Reg)) {
for (unsigned i = 0, e = RegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = RegOpers.Uses[i];
if (!LiveRegs.contains(Reg)) {
// Adjust liveouts if LiveIntervals are available.
if (RequireIntervals) {
const LiveInterval *LI = &LIS->getInterval(Reg);
if (!LI->killedAt(SlotIdx))
discoverVirtLiveOut(Reg);
const LiveInterval *LI = getInterval(Reg);
if (LI && !LI->killedAt(SlotIdx))
discoverLiveOut(Reg);
}
increaseVirtRegPressure(Reg);
LiveVirtRegs.insert(Reg);
increaseRegPressure(Reg);
LiveRegs.insert(Reg);
}
}
return true;
@ -530,53 +485,43 @@ bool RegPressureTracker::advance() {
static_cast<RegionPressure&>(P).openBottom(CurrPos);
}
PhysRegOperands PhysRegOpers;
VirtRegOperands VirtRegOpers;
collectOperands(CurrPos, PhysRegOpers, VirtRegOpers, TRI, MRI);
RegisterOperands RegOpers(TRI, MRI);
collectOperands(CurrPos, RegOpers);
// Kill liveness at last uses.
for (unsigned i = 0, e = PhysRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Uses[i];
// Allocatable physregs are always single-use before register rewriting.
if (LivePhysRegs.erase(Reg))
decreasePhysRegPressure(Reg);
else
discoverPhysLiveIn(Reg);
}
for (unsigned i = 0, e = VirtRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Uses[i];
for (unsigned i = 0, e = RegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = RegOpers.Uses[i];
// Discover live-ins.
bool isLive = LiveRegs.contains(Reg);
if (!isLive)
discoverLiveIn(Reg);
// Kill liveness at last uses.
bool lastUse = false;
if (RequireIntervals) {
const LiveInterval *LI = &LIS->getInterval(Reg);
if (LI->killedAt(SlotIdx)) {
if (LiveVirtRegs.erase(Reg))
decreaseVirtRegPressure(Reg);
else
discoverVirtLiveIn(Reg);
}
const LiveInterval *LI = getInterval(Reg);
lastUse = LI && LI->killedAt(SlotIdx);
}
else if (!LiveVirtRegs.count(Reg)) {
discoverVirtLiveIn(Reg);
increaseVirtRegPressure(Reg);
else {
// Allocatable physregs are always single-use before register rewriting.
lastUse = !TargetRegisterInfo::isVirtualRegister(Reg);
}
if (lastUse && isLive) {
LiveRegs.erase(Reg);
decreaseRegPressure(Reg);
}
else if (!lastUse && !isLive)
increaseRegPressure(Reg);
}
// Generate liveness for defs.
for (unsigned i = 0, e = PhysRegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Defs[i];
if (LivePhysRegs.insert(Reg).second)
increasePhysRegPressure(Reg);
}
for (unsigned i = 0, e = VirtRegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Defs[i];
if (LiveVirtRegs.insert(Reg).second)
increaseVirtRegPressure(Reg);
for (unsigned i = 0, e = RegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = RegOpers.Defs[i];
if (LiveRegs.insert(Reg))
increaseRegPressure(Reg);
}
// Boost pressure for all dead defs together.
increasePhysRegPressure(PhysRegOpers.DeadDefs);
increaseVirtRegPressure(VirtRegOpers.DeadDefs);
decreasePhysRegPressure(PhysRegOpers.DeadDefs);
decreaseVirtRegPressure(VirtRegOpers.DeadDefs);
increaseRegPressure(RegOpers.DeadDefs);
decreaseRegPressure(RegOpers.DeadDefs);
// Find the next instruction.
do
@ -667,39 +612,28 @@ static void computeMaxPressureDelta(ArrayRef<unsigned> OldMaxPressureVec,
/// This is intended for speculative queries. It leaves pressure inconsistent
/// with the current position, so must be restored by the caller.
void RegPressureTracker::bumpUpwardPressure(const MachineInstr *MI) {
assert(!MI->isDebugValue() && "Expect a nondebug instruction.");
// Account for register pressure similar to RegPressureTracker::recede().
PhysRegOperands PhysRegOpers;
VirtRegOperands VirtRegOpers;
collectOperands(MI, PhysRegOpers, VirtRegOpers, TRI, MRI);
RegisterOperands RegOpers(TRI, MRI);
collectOperands(MI, RegOpers);
// Boost max pressure for all dead defs together.
// Since CurrSetPressure and MaxSetPressure
increasePhysRegPressure(PhysRegOpers.DeadDefs);
increaseVirtRegPressure(VirtRegOpers.DeadDefs);
decreasePhysRegPressure(PhysRegOpers.DeadDefs);
decreaseVirtRegPressure(VirtRegOpers.DeadDefs);
increaseRegPressure(RegOpers.DeadDefs);
decreaseRegPressure(RegOpers.DeadDefs);
// Kill liveness at live defs.
for (unsigned i = 0, e = PhysRegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Defs[i];
if (!containsReg(PhysRegOpers.Uses, Reg))
decreasePhysRegPressure(Reg);
}
for (unsigned i = 0, e = VirtRegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Defs[i];
if (!containsReg(VirtRegOpers.Uses, Reg))
decreaseVirtRegPressure(Reg);
for (unsigned i = 0, e = RegOpers.Defs.size(); i < e; ++i) {
unsigned Reg = RegOpers.Defs[i];
if (!containsReg(RegOpers.Uses, Reg))
decreaseRegPressure(Reg);
}
// Generate liveness for uses.
for (unsigned i = 0, e = PhysRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Uses[i];
if (!LivePhysRegs.count(Reg))
increasePhysRegPressure(Reg);
}
for (unsigned i = 0, e = VirtRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Uses[i];
if (!LiveVirtRegs.count(Reg))
increaseVirtRegPressure(Reg);
for (unsigned i = 0, e = RegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = RegOpers.Uses[i];
if (!LiveRegs.contains(Reg))
increaseRegPressure(Reg);
}
}
@ -760,38 +694,42 @@ static bool findUseBetween(unsigned Reg,
/// This is intended for speculative queries. It leaves pressure inconsistent
/// with the current position, so must be restored by the caller.
void RegPressureTracker::bumpDownwardPressure(const MachineInstr *MI) {
assert(!MI->isDebugValue() && "Expect a nondebug instruction.");
// Account for register pressure similar to RegPressureTracker::recede().
PhysRegOperands PhysRegOpers;
VirtRegOperands VirtRegOpers;
collectOperands(MI, PhysRegOpers, VirtRegOpers, TRI, MRI);
RegisterOperands RegOpers(TRI, MRI);
collectOperands(MI, RegOpers);
// Kill liveness at last uses. Assume allocatable physregs are single-use
// rather than checking LiveIntervals.
decreasePhysRegPressure(PhysRegOpers.Uses);
if (RequireIntervals) {
SlotIndex SlotIdx = LIS->getInstructionIndex(MI).getRegSlot();
for (unsigned i = 0, e = VirtRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Uses[i];
const LiveInterval *LI = &LIS->getInterval(Reg);
// FIXME: allow the caller to pass in the list of vreg uses that remain to
// be bottom-scheduled to avoid searching uses at each query.
SlotIndex SlotIdx;
if (RequireIntervals)
SlotIdx = LIS->getInstructionIndex(MI).getRegSlot();
for (unsigned i = 0, e = RegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = RegOpers.Uses[i];
if (RequireIntervals) {
// FIXME: allow the caller to pass in the list of vreg uses that remain
// to be bottom-scheduled to avoid searching uses at each query.
SlotIndex CurrIdx = getCurrSlot();
if (LI->killedAt(SlotIdx)
const LiveInterval *LI = getInterval(Reg);
if (LI && LI->killedAt(SlotIdx)
&& !findUseBetween(Reg, CurrIdx, SlotIdx, MRI, LIS)) {
decreaseVirtRegPressure(Reg);
decreaseRegPressure(Reg);
}
}
else if (!TargetRegisterInfo::isVirtualRegister(Reg)) {
// Allocatable physregs are always single-use before register rewriting.
decreaseRegPressure(Reg);
}
}
// Generate liveness for defs.
increasePhysRegPressure(PhysRegOpers.Defs);
increaseVirtRegPressure(VirtRegOpers.Defs);
increaseRegPressure(RegOpers.Defs);
// Boost pressure for all dead defs together.
increasePhysRegPressure(PhysRegOpers.DeadDefs);
increaseVirtRegPressure(VirtRegOpers.DeadDefs);
decreasePhysRegPressure(PhysRegOpers.DeadDefs);
decreaseVirtRegPressure(VirtRegOpers.DeadDefs);
increaseRegPressure(RegOpers.DeadDefs);
decreaseRegPressure(RegOpers.DeadDefs);
}
/// Consider the pressure increase caused by traversing this instruction