//
//===----------------------------------------------------------------------===//
-#include "RegisterClassInfo.h"
-#include "RegisterPressure.h"
#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/RegisterClassInfo.h"
+#include "llvm/CodeGen/RegisterPressure.h"
#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
using namespace llvm;
decreaseSetPressure(MaxSetPressure, RC, TRI);
}
+void RegisterPressure::dump(const TargetRegisterInfo *TRI) {
+ dbgs() << "Live In: ";
+ for (unsigned i = 0, e = LiveInRegs.size(); i < e; ++i)
+ dbgs() << PrintReg(LiveInRegs[i], TRI) << " ";
+ dbgs() << '\n';
+ dbgs() << "Live Out: ";
+ for (unsigned i = 0, e = LiveOutRegs.size(); i < e; ++i)
+ dbgs() << PrintReg(LiveOutRegs[i], TRI) << " ";
+ dbgs() << '\n';
+ for (unsigned i = 0, e = MaxSetPressure.size(); i < e; ++i) {
+ if (MaxSetPressure[i] != 0)
+ dbgs() << TRI->getRegPressureSetName(i) << "=" << MaxSetPressure[i]
+ << '\n';
+ }
+}
+
/// Increase the current pressure as impacted by these physical registers and
/// bump the high water mark if needed.
void RegPressureTracker::increasePhysRegPressure(ArrayRef<unsigned> Regs) {
static bool hasRegAlias(unsigned Reg, SparseSet<unsigned> &Regs,
const TargetRegisterInfo *TRI) {
assert(!TargetRegisterInfo::isVirtualRegister(Reg) && "only for physregs");
- for (const uint16_t *Alias = TRI->getOverlaps(Reg); *Alias; ++Alias) {
- if (Regs.count(*Alias))
+ for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI)
+ if (Regs.count(*AI))
return true;
- }
return false;
}
static SmallVectorImpl<unsigned>::iterator
findRegAlias(unsigned Reg, SmallVectorImpl<unsigned> &Regs,
const TargetRegisterInfo *TRI) {
- for (const uint16_t *Alias = TRI->getOverlaps(Reg); *Alias; ++Alias) {
+ for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI) {
SmallVectorImpl<unsigned>::iterator I =
- std::find(Regs.begin(), Regs.end(), *Alias);
+ std::find(Regs.begin(), Regs.end(), *AI);
if (I != Regs.end())
return 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");
- if (findRegAlias(Reg, P.LiveInRegs, TRI) == P.LiveInRegs.end())
+ if (findRegAlias(Reg, P.LiveInRegs, TRI) != P.LiveInRegs.end())
return;
// At live in discovery, unconditionally increase the high water mark.
/// 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");
- if (findRegAlias(Reg, P.LiveOutRegs, TRI) == P.LiveOutRegs.end())
+ if (findRegAlias(Reg, P.LiveOutRegs, TRI) != P.LiveOutRegs.end())
return;
// At live out discovery, unconditionally increase the high water mark.
}
}
-/// Consider the pressure increase caused by traversing this instruction
-/// bottom-up. Find the pressure set with the most change beyond its pressure
-/// limit based on the tracker's current pressure, and return the change in
-/// number of register units of that pressure set introduced by this
-/// instruction.
-///
-/// This assumes that the current LiveOut set is sufficient.
+/// Record the upward impact of a single instruction on current register
+/// pressure. Unlike the advance/recede pressure tracking interface, this does
+/// not discover live in/outs.
///
-/// FIXME: This is expensive for an on-the-fly query. We need to cache the
-/// result per-SUnit with enough information to adjust for the current
-/// scheduling position. But this works as a proof of concept.
-void RegPressureTracker::
-getMaxUpwardPressureDelta(const MachineInstr *MI, RegPressureDelta &Delta,
- ArrayRef<PressureElement> CriticalPSets,
- ArrayRef<unsigned> MaxPressureLimit) {
+/// 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) {
// Account for register pressure similar to RegPressureTracker::recede().
PhysRegOperands PhysRegOpers;
VirtRegOperands VirtRegOpers;
collectOperands(MI, PhysRegOpers, VirtRegOpers, TRI, RCI);
- // Snapshot Pressure.
- // FIXME: The snapshot heap space should persist. But I'm planning to
- // summarize the pressure effect so we don't need to snapshot at all.
- std::vector<unsigned> SavedPressure = CurrSetPressure;
- std::vector<unsigned> SavedMaxPressure = P.MaxSetPressure;
-
// Boost max pressure for all dead defs together.
// Since CurrSetPressure and MaxSetPressure
increasePhysRegPressure(PhysRegOpers.DeadDefs);
// Generate liveness for uses.
for (unsigned i = 0, e = PhysRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = PhysRegOpers.Uses[i];
- if (!hasRegAlias(Reg, LivePhysRegs, TRI)
- && (findRegAlias(Reg, PhysRegOpers.Defs, TRI)
- == PhysRegOpers.Defs.end())) {
+ if (!hasRegAlias(Reg, LivePhysRegs, TRI))
increasePhysRegPressure(Reg);
- }
}
for (unsigned i = 0, e = VirtRegOpers.Uses.size(); i < e; ++i) {
unsigned Reg = VirtRegOpers.Uses[i];
- if (!LiveVirtRegs.count(Reg)
- && (std::find(VirtRegOpers.Defs.begin(), VirtRegOpers.Defs.end(), Reg)
- != VirtRegOpers.Defs.end())) {
+ if (!LiveVirtRegs.count(Reg))
increaseVirtRegPressure(Reg);
- }
}
+}
+
+/// Consider the pressure increase caused by traversing this instruction
+/// bottom-up. Find the pressure set with the most change beyond its pressure
+/// limit based on the tracker's current pressure, and return the change in
+/// number of register units of that pressure set introduced by this
+/// instruction.
+///
+/// This assumes that the current LiveOut set is sufficient.
+///
+/// FIXME: This is expensive for an on-the-fly query. We need to cache the
+/// result per-SUnit with enough information to adjust for the current
+/// scheduling position. But this works as a proof of concept.
+void RegPressureTracker::
+getMaxUpwardPressureDelta(const MachineInstr *MI, RegPressureDelta &Delta,
+ ArrayRef<PressureElement> CriticalPSets,
+ ArrayRef<unsigned> MaxPressureLimit) {
+ // Snapshot Pressure.
+ // FIXME: The snapshot heap space should persist. But I'm planning to
+ // summarize the pressure effect so we don't need to snapshot at all.
+ std::vector<unsigned> SavedPressure = CurrSetPressure;
+ std::vector<unsigned> SavedMaxPressure = P.MaxSetPressure;
+
+ bumpUpwardPressure(MI);
+
computeExcessPressureDelta(SavedPressure, CurrSetPressure, Delta, TRI);
computeMaxPressureDelta(SavedMaxPressure, P.MaxSetPressure, CriticalPSets,
MaxPressureLimit, Delta);
return false;
}
-/// Consider the pressure increase caused by traversing this instruction
-/// top-down. Find the register class with the most change in its pressure limit
-/// based on the tracker's current pressure, and return the number of excess
-/// register units of that pressure set introduced by this instruction.
+/// Record the downward impact of a single instruction on current register
+/// pressure. Unlike the advance/recede pressure tracking interface, this does
+/// not discover live in/outs.
///
-/// This assumes that the current LiveIn set is sufficient.
-void RegPressureTracker::
-getMaxDownwardPressureDelta(const MachineInstr *MI, RegPressureDelta &Delta,
- ArrayRef<PressureElement> CriticalPSets,
- ArrayRef<unsigned> MaxPressureLimit) {
+/// 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) {
// Account for register pressure similar to RegPressureTracker::recede().
PhysRegOperands PhysRegOpers;
VirtRegOperands VirtRegOpers;
collectOperands(MI, PhysRegOpers, VirtRegOpers, TRI, RCI);
- // Snapshot Pressure.
- std::vector<unsigned> SavedPressure = CurrSetPressure;
- std::vector<unsigned> SavedMaxPressure = P.MaxSetPressure;
-
// Kill liveness at last uses. Assume allocatable physregs are single-use
// rather than checking LiveIntervals.
decreasePhysRegPressure(PhysRegOpers.Uses);
increaseVirtRegPressure(VirtRegOpers.DeadDefs);
decreasePhysRegPressure(PhysRegOpers.DeadDefs);
decreaseVirtRegPressure(VirtRegOpers.DeadDefs);
+}
+
+/// Consider the pressure increase caused by traversing this instruction
+/// top-down. Find the register class with the most change in its pressure limit
+/// based on the tracker's current pressure, and return the number of excess
+/// register units of that pressure set introduced by this instruction.
+///
+/// This assumes that the current LiveIn set is sufficient.
+void RegPressureTracker::
+getMaxDownwardPressureDelta(const MachineInstr *MI, RegPressureDelta &Delta,
+ ArrayRef<PressureElement> CriticalPSets,
+ ArrayRef<unsigned> MaxPressureLimit) {
+ // Snapshot Pressure.
+ std::vector<unsigned> SavedPressure = CurrSetPressure;
+ std::vector<unsigned> SavedMaxPressure = P.MaxSetPressure;
+
+ bumpDownwardPressure(MI);
computeExcessPressureDelta(SavedPressure, CurrSetPressure, Delta, TRI);
computeMaxPressureDelta(SavedMaxPressure, P.MaxSetPressure, CriticalPSets,
P.MaxSetPressure.swap(SavedMaxPressure);
CurrSetPressure.swap(SavedPressure);
}
+
+/// Get the pressure of each PSet after traversing this instruction bottom-up.
+void RegPressureTracker::
+getUpwardPressure(const MachineInstr *MI,
+ std::vector<unsigned> &PressureResult,
+ std::vector<unsigned> &MaxPressureResult) {
+ // Snapshot pressure.
+ PressureResult = CurrSetPressure;
+ MaxPressureResult = P.MaxSetPressure;
+
+ bumpUpwardPressure(MI);
+
+ // Current pressure becomes the result. Restore current pressure.
+ P.MaxSetPressure.swap(MaxPressureResult);
+ CurrSetPressure.swap(PressureResult);
+}
+
+/// Get the pressure of each PSet after traversing this instruction top-down.
+void RegPressureTracker::
+getDownwardPressure(const MachineInstr *MI,
+ std::vector<unsigned> &PressureResult,
+ std::vector<unsigned> &MaxPressureResult) {
+ // Snapshot pressure.
+ PressureResult = CurrSetPressure;
+ MaxPressureResult = P.MaxSetPressure;
+
+ bumpDownwardPressure(MI);
+
+ // Current pressure becomes the result. Restore current pressure.
+ P.MaxSetPressure.swap(MaxPressureResult);
+ CurrSetPressure.swap(PressureResult);
+}
projects / oota-llvm.git / blobdiff