diff options
Diffstat (limited to 'lib/CodeGen')
| -rw-r--r-- | lib/CodeGen/MachineScheduler.cpp | 2 | ||||
| -rw-r--r-- | lib/CodeGen/RegisterPressure.cpp | 2 | ||||
| -rw-r--r-- | lib/CodeGen/RegisterPressure.h | 255 | ||||
| -rw-r--r-- | lib/CodeGen/ScheduleDAGInstrs.cpp | 2 |
4 files changed, 3 insertions, 258 deletions
diff --git a/lib/CodeGen/MachineScheduler.cpp b/lib/CodeGen/MachineScheduler.cpp index aa591779ba..f3f95d86df 100644 --- a/lib/CodeGen/MachineScheduler.cpp +++ b/lib/CodeGen/MachineScheduler.cpp @@ -15,10 +15,10 @@ #define DEBUG_TYPE "misched" #include "RegisterClassInfo.h" -#include "RegisterPressure.h" #include "llvm/CodeGen/LiveIntervalAnalysis.h" #include "llvm/CodeGen/MachineScheduler.h" #include "llvm/CodeGen/Passes.h" +#include "llvm/CodeGen/RegisterPressure.h" #include "llvm/CodeGen/ScheduleDAGInstrs.h" #include "llvm/CodeGen/ScheduleHazardRecognizer.h" #include "llvm/Target/TargetInstrInfo.h" diff --git a/lib/CodeGen/RegisterPressure.cpp b/lib/CodeGen/RegisterPressure.cpp index ea2bb6b266..d39ef722a3 100644 --- a/lib/CodeGen/RegisterPressure.cpp +++ b/lib/CodeGen/RegisterPressure.cpp @@ -13,10 +13,10 @@ //===----------------------------------------------------------------------===// #include "RegisterClassInfo.h" -#include "RegisterPressure.h" #include "llvm/CodeGen/LiveInterval.h" #include "llvm/CodeGen/LiveIntervalAnalysis.h" #include "llvm/CodeGen/MachineRegisterInfo.h" +#include "llvm/CodeGen/RegisterPressure.h" #include "llvm/Target/TargetMachine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" diff --git a/lib/CodeGen/RegisterPressure.h b/lib/CodeGen/RegisterPressure.h deleted file mode 100644 index dd7ba86d19..0000000000 --- a/lib/CodeGen/RegisterPressure.h +++ /dev/null @@ -1,255 +0,0 @@ -//===-- RegisterPressure.h - Dynamic Register Pressure -*- C++ -*-------===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// -// This file defines the RegisterPressure class which can be used to track -// MachineInstr level register pressure. -// -//===----------------------------------------------------------------------===// - -#ifndef LLVM_CODEGEN_REGISTERPRESSURE_H -#define LLVM_CODEGEN_REGISTERPRESSURE_H - -#include "llvm/CodeGen/SlotIndexes.h" -#include "llvm/Target/TargetRegisterInfo.h" -#include "llvm/ADT/SparseSet.h" - -namespace llvm { - -class LiveIntervals; -class RegisterClassInfo; -class MachineInstr; - -/// Base class for register pressure results. -struct RegisterPressure { - /// Map of max reg pressure indexed by pressure set ID, not class ID. - std::vector<unsigned> MaxSetPressure; - - /// List of live in registers. - SmallVector<unsigned,8> LiveInRegs; - SmallVector<unsigned,8> LiveOutRegs; - - /// 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); - - /// 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); - - void dump(const TargetRegisterInfo *TRI); -}; - -/// RegisterPressure computed within a region of instructions delimited by -/// TopIdx and BottomIdx. During pressure computation, the maximum pressure per -/// register pressure set is increased. Once pressure within a region is fully -/// computed, the live-in and live-out sets are recorded. -/// -/// This is preferable to RegionPressure when LiveIntervals are available, -/// because delimiting regions by SlotIndex is more robust and convenient than -/// holding block iterators. The block contents can change without invalidating -/// the pressure result. -struct IntervalPressure : RegisterPressure { - /// Record the boundary of the region being tracked. - SlotIndex TopIdx; - SlotIndex BottomIdx; - - void reset(); - - void openTop(SlotIndex NextTop); - - void openBottom(SlotIndex PrevBottom); -}; - -/// RegisterPressure computed within a region of instructions delimited by -/// TopPos and BottomPos. This is a less precise version of IntervalPressure for -/// use when LiveIntervals are unavailable. -struct RegionPressure : RegisterPressure { - /// Record the boundary of the region being tracked. - MachineBasicBlock::const_iterator TopPos; - MachineBasicBlock::const_iterator BottomPos; - - void reset(); - - void openTop(MachineBasicBlock::const_iterator PrevTop); - - void openBottom(MachineBasicBlock::const_iterator PrevBottom); -}; - -/// An element of pressure difference that identifies the pressure set and -/// amount of increase or decrease in units of pressure. -struct PressureElement { - unsigned PSetID; - int UnitIncrease; - - PressureElement(): PSetID(~0U), UnitIncrease(0) {} - PressureElement(unsigned id, int inc): PSetID(id), UnitIncrease(inc) {} - - bool isValid() const { return PSetID != ~0U; } -}; - -/// Store the effects of a change in pressure on things that MI scheduler cares -/// about. -/// -/// Excess records the value of the largest difference in register units beyond -/// the target's pressure limits across the affected pressure sets, where -/// largest is defined as the absolute value of the difference. Negative -/// ExcessUnits indicates a reduction in pressure that had already exceeded the -/// target's limits. -/// -/// CriticalMax records the largest increase in the tracker's max pressure that -/// exceeds the critical limit for some pressure set determined by the client. -/// -/// CurrentMax records the largest increase in the tracker's max pressure that -/// exceeds the current limit for some pressure set determined by the client. -struct RegPressureDelta { - PressureElement Excess; - PressureElement CriticalMax; - PressureElement CurrentMax; - - RegPressureDelta() {} -}; - -/// 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 -/// independently adjust for global liveness. -/// -/// Each RegPressureTracker only works within a MachineBasicBlock. Pressure can -/// be tracked across a larger region by storing a RegisterPressure result at -/// each block boundary and explicitly adjusting pressure to account for block -/// live-in and live-out register sets. -/// -/// RegPressureTracker holds a reference to a RegisterPressure result that it -/// computes incrementally. During downward tracking, P.BottomIdx or P.BottomPos -/// is invalid until it reaches the end of the block or closeRegion() is -/// explicitly called. Similarly, P.TopIdx is invalid during upward -/// tracking. Changing direction has the side effect of closing region, and -/// traversing past TopIdx or BottomIdx reopens it. -class RegPressureTracker { - const MachineFunction *MF; - const TargetRegisterInfo *TRI; - const RegisterClassInfo *RCI; - const MachineRegisterInfo *MRI; - const LiveIntervals *LIS; - - /// We currently only allow pressure tracking within a block. - const MachineBasicBlock *MBB; - - /// Track the max pressure within the region traversed so far. - RegisterPressure &P; - - /// Run in two modes dependending on whether constructed with IntervalPressure - /// or RegisterPressure. If requireIntervals is false, LIS are ignored. - bool RequireIntervals; - - /// Register pressure corresponds to liveness before this instruction - /// iterator. It may point to the end of the block rather than an instruction. - MachineBasicBlock::const_iterator CurrPos; - - /// 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; - -public: - RegPressureTracker(IntervalPressure &rp) : - MF(0), TRI(0), RCI(0), LIS(0), MBB(0), P(rp), RequireIntervals(true) {} - - RegPressureTracker(RegionPressure &rp) : - MF(0), TRI(0), RCI(0), LIS(0), MBB(0), P(rp), RequireIntervals(false) {} - - void init(const MachineFunction *mf, const RegisterClassInfo *rci, - const LiveIntervals *lis, const MachineBasicBlock *mbb, - MachineBasicBlock::const_iterator pos); - - /// Force liveness of registers. Particularly useful to initialize the - /// livein/out state of the tracker before the first call to advance/recede. - void addLiveRegs(ArrayRef<unsigned> Regs); - - /// Get the MI position corresponding to this register pressure. - MachineBasicBlock::const_iterator getPos() const { return CurrPos; } - - // Reset the MI position corresponding to the register pressure. This allows - // schedulers to move instructions above the RegPressureTracker's - // CurrPos. Since the pressure is computed before CurrPos, the iterator - // position changes while pressure does not. - void setPos(MachineBasicBlock::const_iterator Pos) { CurrPos = Pos; } - - /// Recede across the previous instruction. - bool recede(); - - /// Advance across the current instruction. - bool advance(); - - /// Finalize the region boundaries and recored live ins and live outs. - void closeRegion(); - - /// Get the resulting register pressure over the traversed region. - /// This result is complete if either advance() or recede() has returned true, - /// or if closeRegion() was explicitly invoked. - RegisterPressure &getPressure() { return P; } - - void discoverPhysLiveIn(unsigned Reg); - void discoverPhysLiveOut(unsigned Reg); - - void discoverVirtLiveIn(unsigned Reg); - void discoverVirtLiveOut(unsigned Reg); - - bool isTopClosed() const; - bool isBottomClosed() const; - - void closeTop(); - void closeBottom(); - - /// 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 record the number of - /// excess register units of that pressure set introduced by this instruction. - void getMaxUpwardPressureDelta(const MachineInstr *MI, - RegPressureDelta &Delta, - ArrayRef<PressureElement> CriticalPSets, - ArrayRef<unsigned> MaxPressureLimit); - - /// Consider the pressure increase caused by traversing this instruction - /// top-down. Find the pressure set with the most change beyond its pressure - /// limit based on the tracker's current pressure, and record the number of - /// excess register units of that pressure set introduced by this instruction. - void getMaxDownwardPressureDelta(const MachineInstr *MI, - RegPressureDelta &Delta, - ArrayRef<PressureElement> CriticalPSets, - ArrayRef<unsigned> MaxPressureLimit); - - /// Find the pressure set with the most change beyond its pressure limit after - /// traversing this instruction either upward or downward depending on the - /// closed end of the current region. - void getMaxPressureDelta(const MachineInstr *MI, RegPressureDelta &Delta, - ArrayRef<PressureElement> CriticalPSets, - ArrayRef<unsigned> MaxPressureLimit) { - if (isTopClosed()) - return getMaxDownwardPressureDelta(MI, Delta, CriticalPSets, - MaxPressureLimit); - - assert(isBottomClosed() && "Uninitialized pressure tracker"); - return getMaxUpwardPressureDelta(MI, Delta, CriticalPSets, - MaxPressureLimit); - } - -protected: - void increasePhysRegPressure(ArrayRef<unsigned> Regs); - void decreasePhysRegPressure(ArrayRef<unsigned> Regs); - - void increaseVirtRegPressure(ArrayRef<unsigned> Regs); - void decreaseVirtRegPressure(ArrayRef<unsigned> Regs); -}; -} // end namespace llvm - -#endif diff --git a/lib/CodeGen/ScheduleDAGInstrs.cpp b/lib/CodeGen/ScheduleDAGInstrs.cpp index e78f5c92b4..6e80335f4b 100644 --- a/lib/CodeGen/ScheduleDAGInstrs.cpp +++ b/lib/CodeGen/ScheduleDAGInstrs.cpp @@ -13,7 +13,6 @@ //===----------------------------------------------------------------------===// #define DEBUG_TYPE "sched-instrs" -#include "RegisterPressure.h" #include "llvm/Operator.h" #include "llvm/Analysis/AliasAnalysis.h" #include "llvm/Analysis/ValueTracking.h" @@ -22,6 +21,7 @@ #include "llvm/CodeGen/MachineMemOperand.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/PseudoSourceValue.h" +#include "llvm/CodeGen/RegisterPressure.h" #include "llvm/CodeGen/ScheduleDAGInstrs.h" #include "llvm/MC/MCInstrItineraries.h" #include "llvm/Target/TargetMachine.h" |