mirror of
https://github.com/RPCSX/llvm.git
synced 2024-11-29 22:50:47 +00:00
49c8aa0d8b
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66870 91177308-0d34-0410-b5e6-96231b3b80d8
449 lines
17 KiB
C++
449 lines
17 KiB
C++
//===-- llvm/CodeGen/VirtRegMap.h - Virtual Register Map -*- C++ -*--------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file implements a virtual register map. This maps virtual registers to
|
|
// physical registers and virtual registers to stack slots. It is created and
|
|
// updated by a register allocator and then used by a machine code rewriter that
|
|
// adds spill code and rewrites virtual into physical register references.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_CODEGEN_VIRTREGMAP_H
|
|
#define LLVM_CODEGEN_VIRTREGMAP_H
|
|
|
|
#include "llvm/CodeGen/MachineFunctionPass.h"
|
|
#include "llvm/Target/TargetRegisterInfo.h"
|
|
#include "llvm/ADT/BitVector.h"
|
|
#include "llvm/ADT/IndexedMap.h"
|
|
#include "llvm/ADT/SmallPtrSet.h"
|
|
#include "llvm/ADT/SmallVector.h"
|
|
#include "llvm/Support/Streams.h"
|
|
#include <map>
|
|
|
|
namespace llvm {
|
|
class MachineInstr;
|
|
class MachineFunction;
|
|
class TargetInstrInfo;
|
|
|
|
class VirtRegMap : public MachineFunctionPass {
|
|
public:
|
|
enum {
|
|
NO_PHYS_REG = 0,
|
|
NO_STACK_SLOT = (1L << 30)-1,
|
|
MAX_STACK_SLOT = (1L << 18)-1
|
|
};
|
|
|
|
enum ModRef { isRef = 1, isMod = 2, isModRef = 3 };
|
|
typedef std::multimap<MachineInstr*,
|
|
std::pair<unsigned, ModRef> > MI2VirtMapTy;
|
|
|
|
private:
|
|
const TargetInstrInfo *TII;
|
|
|
|
MachineFunction *MF;
|
|
/// Virt2PhysMap - This is a virtual to physical register
|
|
/// mapping. Each virtual register is required to have an entry in
|
|
/// it; even spilled virtual registers (the register mapped to a
|
|
/// spilled register is the temporary used to load it from the
|
|
/// stack).
|
|
IndexedMap<unsigned, VirtReg2IndexFunctor> Virt2PhysMap;
|
|
|
|
/// Virt2StackSlotMap - This is virtual register to stack slot
|
|
/// mapping. Each spilled virtual register has an entry in it
|
|
/// which corresponds to the stack slot this register is spilled
|
|
/// at.
|
|
IndexedMap<int, VirtReg2IndexFunctor> Virt2StackSlotMap;
|
|
|
|
/// Virt2ReMatIdMap - This is virtual register to rematerialization id
|
|
/// mapping. Each spilled virtual register that should be remat'd has an
|
|
/// entry in it which corresponds to the remat id.
|
|
IndexedMap<int, VirtReg2IndexFunctor> Virt2ReMatIdMap;
|
|
|
|
/// Virt2SplitMap - This is virtual register to splitted virtual register
|
|
/// mapping.
|
|
IndexedMap<unsigned, VirtReg2IndexFunctor> Virt2SplitMap;
|
|
|
|
/// Virt2SplitKillMap - This is splitted virtual register to its last use
|
|
/// (kill) index mapping.
|
|
IndexedMap<unsigned> Virt2SplitKillMap;
|
|
|
|
/// ReMatMap - This is virtual register to re-materialized instruction
|
|
/// mapping. Each virtual register whose definition is going to be
|
|
/// re-materialized has an entry in it.
|
|
IndexedMap<MachineInstr*, VirtReg2IndexFunctor> ReMatMap;
|
|
|
|
/// MI2VirtMap - This is MachineInstr to virtual register
|
|
/// mapping. In the case of memory spill code being folded into
|
|
/// instructions, we need to know which virtual register was
|
|
/// read/written by this instruction.
|
|
MI2VirtMapTy MI2VirtMap;
|
|
|
|
/// SpillPt2VirtMap - This records the virtual registers which should
|
|
/// be spilled right after the MachineInstr due to live interval
|
|
/// splitting.
|
|
std::map<MachineInstr*, std::vector<std::pair<unsigned,bool> > >
|
|
SpillPt2VirtMap;
|
|
|
|
/// RestorePt2VirtMap - This records the virtual registers which should
|
|
/// be restored right before the MachineInstr due to live interval
|
|
/// splitting.
|
|
std::map<MachineInstr*, std::vector<unsigned> > RestorePt2VirtMap;
|
|
|
|
/// EmergencySpillMap - This records the physical registers that should
|
|
/// be spilled / restored around the MachineInstr since the register
|
|
/// allocator has run out of registers.
|
|
std::map<MachineInstr*, std::vector<unsigned> > EmergencySpillMap;
|
|
|
|
/// EmergencySpillSlots - This records emergency spill slots used to
|
|
/// spill physical registers when the register allocator runs out of
|
|
/// registers. Ideally only one stack slot is used per function per
|
|
/// register class.
|
|
std::map<const TargetRegisterClass*, int> EmergencySpillSlots;
|
|
|
|
/// ReMatId - Instead of assigning a stack slot to a to be rematerialized
|
|
/// virtual register, an unique id is being assigned. This keeps track of
|
|
/// the highest id used so far. Note, this starts at (1<<18) to avoid
|
|
/// conflicts with stack slot numbers.
|
|
int ReMatId;
|
|
|
|
/// LowSpillSlot, HighSpillSlot - Lowest and highest spill slot indexes.
|
|
int LowSpillSlot, HighSpillSlot;
|
|
|
|
/// SpillSlotToUsesMap - Records uses for each register spill slot.
|
|
SmallVector<SmallPtrSet<MachineInstr*, 4>, 8> SpillSlotToUsesMap;
|
|
|
|
/// ImplicitDefed - One bit for each virtual register. If set it indicates
|
|
/// the register is implicitly defined.
|
|
BitVector ImplicitDefed;
|
|
|
|
VirtRegMap(const VirtRegMap&); // DO NOT IMPLEMENT
|
|
void operator=(const VirtRegMap&); // DO NOT IMPLEMENT
|
|
|
|
public:
|
|
static char ID;
|
|
VirtRegMap() : MachineFunctionPass(&ID), Virt2PhysMap(NO_PHYS_REG),
|
|
Virt2StackSlotMap(NO_STACK_SLOT),
|
|
Virt2ReMatIdMap(NO_STACK_SLOT), Virt2SplitMap(0),
|
|
Virt2SplitKillMap(0), ReMatMap(NULL),
|
|
ReMatId(MAX_STACK_SLOT+1),
|
|
LowSpillSlot(NO_STACK_SLOT), HighSpillSlot(NO_STACK_SLOT) { }
|
|
virtual bool runOnMachineFunction(MachineFunction &MF);
|
|
|
|
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
|
|
AU.setPreservesAll();
|
|
MachineFunctionPass::getAnalysisUsage(AU);
|
|
}
|
|
|
|
void grow();
|
|
|
|
/// @brief returns true if the specified virtual register is
|
|
/// mapped to a physical register
|
|
bool hasPhys(unsigned virtReg) const {
|
|
return getPhys(virtReg) != NO_PHYS_REG;
|
|
}
|
|
|
|
/// @brief returns the physical register mapped to the specified
|
|
/// virtual register
|
|
unsigned getPhys(unsigned virtReg) const {
|
|
assert(TargetRegisterInfo::isVirtualRegister(virtReg));
|
|
return Virt2PhysMap[virtReg];
|
|
}
|
|
|
|
/// @brief creates a mapping for the specified virtual register to
|
|
/// the specified physical register
|
|
void assignVirt2Phys(unsigned virtReg, unsigned physReg) {
|
|
assert(TargetRegisterInfo::isVirtualRegister(virtReg) &&
|
|
TargetRegisterInfo::isPhysicalRegister(physReg));
|
|
assert(Virt2PhysMap[virtReg] == NO_PHYS_REG &&
|
|
"attempt to assign physical register to already mapped "
|
|
"virtual register");
|
|
Virt2PhysMap[virtReg] = physReg;
|
|
}
|
|
|
|
/// @brief clears the specified virtual register's, physical
|
|
/// register mapping
|
|
void clearVirt(unsigned virtReg) {
|
|
assert(TargetRegisterInfo::isVirtualRegister(virtReg));
|
|
assert(Virt2PhysMap[virtReg] != NO_PHYS_REG &&
|
|
"attempt to clear a not assigned virtual register");
|
|
Virt2PhysMap[virtReg] = NO_PHYS_REG;
|
|
}
|
|
|
|
/// @brief clears all virtual to physical register mappings
|
|
void clearAllVirt() {
|
|
Virt2PhysMap.clear();
|
|
grow();
|
|
}
|
|
|
|
/// @brief records virtReg is a split live interval from SReg.
|
|
void setIsSplitFromReg(unsigned virtReg, unsigned SReg) {
|
|
Virt2SplitMap[virtReg] = SReg;
|
|
}
|
|
|
|
/// @brief returns the live interval virtReg is split from.
|
|
unsigned getPreSplitReg(unsigned virtReg) {
|
|
return Virt2SplitMap[virtReg];
|
|
}
|
|
|
|
/// @brief returns true if the specified virtual register is not
|
|
/// mapped to a stack slot or rematerialized.
|
|
bool isAssignedReg(unsigned virtReg) const {
|
|
if (getStackSlot(virtReg) == NO_STACK_SLOT &&
|
|
getReMatId(virtReg) == NO_STACK_SLOT)
|
|
return true;
|
|
// Split register can be assigned a physical register as well as a
|
|
// stack slot or remat id.
|
|
return (Virt2SplitMap[virtReg] && Virt2PhysMap[virtReg] != NO_PHYS_REG);
|
|
}
|
|
|
|
/// @brief returns the stack slot mapped to the specified virtual
|
|
/// register
|
|
int getStackSlot(unsigned virtReg) const {
|
|
assert(TargetRegisterInfo::isVirtualRegister(virtReg));
|
|
return Virt2StackSlotMap[virtReg];
|
|
}
|
|
|
|
/// @brief returns the rematerialization id mapped to the specified virtual
|
|
/// register
|
|
int getReMatId(unsigned virtReg) const {
|
|
assert(TargetRegisterInfo::isVirtualRegister(virtReg));
|
|
return Virt2ReMatIdMap[virtReg];
|
|
}
|
|
|
|
/// @brief create a mapping for the specifed virtual register to
|
|
/// the next available stack slot
|
|
int assignVirt2StackSlot(unsigned virtReg);
|
|
/// @brief create a mapping for the specified virtual register to
|
|
/// the specified stack slot
|
|
void assignVirt2StackSlot(unsigned virtReg, int frameIndex);
|
|
|
|
/// @brief assign an unique re-materialization id to the specified
|
|
/// virtual register.
|
|
int assignVirtReMatId(unsigned virtReg);
|
|
/// @brief assign an unique re-materialization id to the specified
|
|
/// virtual register.
|
|
void assignVirtReMatId(unsigned virtReg, int id);
|
|
|
|
/// @brief returns true if the specified virtual register is being
|
|
/// re-materialized.
|
|
bool isReMaterialized(unsigned virtReg) const {
|
|
return ReMatMap[virtReg] != NULL;
|
|
}
|
|
|
|
/// @brief returns the original machine instruction being re-issued
|
|
/// to re-materialize the specified virtual register.
|
|
MachineInstr *getReMaterializedMI(unsigned virtReg) const {
|
|
return ReMatMap[virtReg];
|
|
}
|
|
|
|
/// @brief records the specified virtual register will be
|
|
/// re-materialized and the original instruction which will be re-issed
|
|
/// for this purpose. If parameter all is true, then all uses of the
|
|
/// registers are rematerialized and it's safe to delete the definition.
|
|
void setVirtIsReMaterialized(unsigned virtReg, MachineInstr *def) {
|
|
ReMatMap[virtReg] = def;
|
|
}
|
|
|
|
/// @brief record the last use (kill) of a split virtual register.
|
|
void addKillPoint(unsigned virtReg, unsigned index) {
|
|
Virt2SplitKillMap[virtReg] = index;
|
|
}
|
|
|
|
unsigned getKillPoint(unsigned virtReg) const {
|
|
return Virt2SplitKillMap[virtReg];
|
|
}
|
|
|
|
/// @brief remove the last use (kill) of a split virtual register.
|
|
void removeKillPoint(unsigned virtReg) {
|
|
Virt2SplitKillMap[virtReg] = 0;
|
|
}
|
|
|
|
/// @brief returns true if the specified MachineInstr is a spill point.
|
|
bool isSpillPt(MachineInstr *Pt) const {
|
|
return SpillPt2VirtMap.find(Pt) != SpillPt2VirtMap.end();
|
|
}
|
|
|
|
/// @brief returns the virtual registers that should be spilled due to
|
|
/// splitting right after the specified MachineInstr.
|
|
std::vector<std::pair<unsigned,bool> > &getSpillPtSpills(MachineInstr *Pt) {
|
|
return SpillPt2VirtMap[Pt];
|
|
}
|
|
|
|
/// @brief records the specified MachineInstr as a spill point for virtReg.
|
|
void addSpillPoint(unsigned virtReg, bool isKill, MachineInstr *Pt) {
|
|
if (SpillPt2VirtMap.find(Pt) != SpillPt2VirtMap.end())
|
|
SpillPt2VirtMap[Pt].push_back(std::make_pair(virtReg, isKill));
|
|
else {
|
|
std::vector<std::pair<unsigned,bool> > Virts;
|
|
Virts.push_back(std::make_pair(virtReg, isKill));
|
|
SpillPt2VirtMap.insert(std::make_pair(Pt, Virts));
|
|
}
|
|
}
|
|
|
|
/// @brief - transfer spill point information from one instruction to
|
|
/// another.
|
|
void transferSpillPts(MachineInstr *Old, MachineInstr *New) {
|
|
std::map<MachineInstr*,std::vector<std::pair<unsigned,bool> > >::iterator
|
|
I = SpillPt2VirtMap.find(Old);
|
|
if (I == SpillPt2VirtMap.end())
|
|
return;
|
|
while (!I->second.empty()) {
|
|
unsigned virtReg = I->second.back().first;
|
|
bool isKill = I->second.back().second;
|
|
I->second.pop_back();
|
|
addSpillPoint(virtReg, isKill, New);
|
|
}
|
|
SpillPt2VirtMap.erase(I);
|
|
}
|
|
|
|
/// @brief returns true if the specified MachineInstr is a restore point.
|
|
bool isRestorePt(MachineInstr *Pt) const {
|
|
return RestorePt2VirtMap.find(Pt) != RestorePt2VirtMap.end();
|
|
}
|
|
|
|
/// @brief returns the virtual registers that should be restoreed due to
|
|
/// splitting right after the specified MachineInstr.
|
|
std::vector<unsigned> &getRestorePtRestores(MachineInstr *Pt) {
|
|
return RestorePt2VirtMap[Pt];
|
|
}
|
|
|
|
/// @brief records the specified MachineInstr as a restore point for virtReg.
|
|
void addRestorePoint(unsigned virtReg, MachineInstr *Pt) {
|
|
if (RestorePt2VirtMap.find(Pt) != RestorePt2VirtMap.end())
|
|
RestorePt2VirtMap[Pt].push_back(virtReg);
|
|
else {
|
|
std::vector<unsigned> Virts;
|
|
Virts.push_back(virtReg);
|
|
RestorePt2VirtMap.insert(std::make_pair(Pt, Virts));
|
|
}
|
|
}
|
|
|
|
/// @brief - transfer restore point information from one instruction to
|
|
/// another.
|
|
void transferRestorePts(MachineInstr *Old, MachineInstr *New) {
|
|
std::map<MachineInstr*,std::vector<unsigned> >::iterator I =
|
|
RestorePt2VirtMap.find(Old);
|
|
if (I == RestorePt2VirtMap.end())
|
|
return;
|
|
while (!I->second.empty()) {
|
|
unsigned virtReg = I->second.back();
|
|
I->second.pop_back();
|
|
addRestorePoint(virtReg, New);
|
|
}
|
|
RestorePt2VirtMap.erase(I);
|
|
}
|
|
|
|
/// @brief records that the specified physical register must be spilled
|
|
/// around the specified machine instr.
|
|
void addEmergencySpill(unsigned PhysReg, MachineInstr *MI) {
|
|
if (EmergencySpillMap.find(MI) != EmergencySpillMap.end())
|
|
EmergencySpillMap[MI].push_back(PhysReg);
|
|
else {
|
|
std::vector<unsigned> PhysRegs;
|
|
PhysRegs.push_back(PhysReg);
|
|
EmergencySpillMap.insert(std::make_pair(MI, PhysRegs));
|
|
}
|
|
}
|
|
|
|
/// @brief returns true if one or more physical registers must be spilled
|
|
/// around the specified instruction.
|
|
bool hasEmergencySpills(MachineInstr *MI) const {
|
|
return EmergencySpillMap.find(MI) != EmergencySpillMap.end();
|
|
}
|
|
|
|
/// @brief returns the physical registers to be spilled and restored around
|
|
/// the instruction.
|
|
std::vector<unsigned> &getEmergencySpills(MachineInstr *MI) {
|
|
return EmergencySpillMap[MI];
|
|
}
|
|
|
|
/// @brief - transfer emergency spill information from one instruction to
|
|
/// another.
|
|
void transferEmergencySpills(MachineInstr *Old, MachineInstr *New) {
|
|
std::map<MachineInstr*,std::vector<unsigned> >::iterator I =
|
|
EmergencySpillMap.find(Old);
|
|
if (I == EmergencySpillMap.end())
|
|
return;
|
|
while (!I->second.empty()) {
|
|
unsigned virtReg = I->second.back();
|
|
I->second.pop_back();
|
|
addEmergencySpill(virtReg, New);
|
|
}
|
|
EmergencySpillMap.erase(I);
|
|
}
|
|
|
|
/// @brief return or get a emergency spill slot for the register class.
|
|
int getEmergencySpillSlot(const TargetRegisterClass *RC);
|
|
|
|
/// @brief Return lowest spill slot index.
|
|
int getLowSpillSlot() const {
|
|
return LowSpillSlot;
|
|
}
|
|
|
|
/// @brief Return highest spill slot index.
|
|
int getHighSpillSlot() const {
|
|
return HighSpillSlot;
|
|
}
|
|
|
|
/// @brief Records a spill slot use.
|
|
void addSpillSlotUse(int FrameIndex, MachineInstr *MI);
|
|
|
|
/// @brief Returns true if spill slot has been used.
|
|
bool isSpillSlotUsed(int FrameIndex) const {
|
|
assert(FrameIndex >= 0 && "Spill slot index should not be negative!");
|
|
return !SpillSlotToUsesMap[FrameIndex-LowSpillSlot].empty();
|
|
}
|
|
|
|
/// @brief Mark the specified register as being implicitly defined.
|
|
void setIsImplicitlyDefined(unsigned VirtReg) {
|
|
ImplicitDefed.set(VirtReg-TargetRegisterInfo::FirstVirtualRegister);
|
|
}
|
|
|
|
/// @brief Returns true if the virtual register is implicitly defined.
|
|
bool isImplicitlyDefined(unsigned VirtReg) const {
|
|
return ImplicitDefed[VirtReg-TargetRegisterInfo::FirstVirtualRegister];
|
|
}
|
|
|
|
/// @brief Updates information about the specified virtual register's value
|
|
/// folded into newMI machine instruction.
|
|
void virtFolded(unsigned VirtReg, MachineInstr *OldMI, MachineInstr *NewMI,
|
|
ModRef MRInfo);
|
|
|
|
/// @brief Updates information about the specified virtual register's value
|
|
/// folded into the specified machine instruction.
|
|
void virtFolded(unsigned VirtReg, MachineInstr *MI, ModRef MRInfo);
|
|
|
|
/// @brief returns the virtual registers' values folded in memory
|
|
/// operands of this instruction
|
|
std::pair<MI2VirtMapTy::const_iterator, MI2VirtMapTy::const_iterator>
|
|
getFoldedVirts(MachineInstr* MI) const {
|
|
return MI2VirtMap.equal_range(MI);
|
|
}
|
|
|
|
/// RemoveMachineInstrFromMaps - MI is being erased, remove it from the
|
|
/// the folded instruction map and spill point map.
|
|
void RemoveMachineInstrFromMaps(MachineInstr *MI);
|
|
|
|
void print(std::ostream &OS, const Module* M = 0) const;
|
|
void print(std::ostream *OS) const { if (OS) print(*OS); }
|
|
void dump() const;
|
|
};
|
|
|
|
inline std::ostream *operator<<(std::ostream *OS, const VirtRegMap &VRM) {
|
|
VRM.print(OS);
|
|
return OS;
|
|
}
|
|
inline std::ostream &operator<<(std::ostream &OS, const VirtRegMap &VRM) {
|
|
VRM.print(OS);
|
|
return OS;
|
|
}
|
|
} // End llvm namespace
|
|
|
|
#endif
|