//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 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.
+// 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/MachineFunction.h"
-#include "llvm/CodeGen/SSARegMap.h"
-#include <climits>
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/ADT/IndexedMap.h"
namespace llvm {
-
- class VirtRegMap {
- public:
- typedef std::vector<unsigned> Virt2PhysMap;
- typedef std::vector<int> Virt2StackSlotMap;
-
- enum {
- NO_PHYS_REG = 0,
- NO_STACK_SLOT = INT_MAX
- };
-
- private:
- MachineFunction* mf_;
- Virt2PhysMap v2pMap_;
- Virt2StackSlotMap v2ssMap_;
-
- // do not implement
- VirtRegMap(const VirtRegMap& rhs);
- const VirtRegMap& operator=(const VirtRegMap& rhs);
-
- static unsigned toIndex(unsigned virtReg) {
- return virtReg - MRegisterInfo::FirstVirtualRegister;
- }
- static unsigned fromIndex(unsigned index) {
- return index + MRegisterInfo::FirstVirtualRegister;
- }
-
- public:
- VirtRegMap(MachineFunction& mf)
- : mf_(&mf),
- v2pMap_(mf.getSSARegMap()->getNumVirtualRegs(), NO_PHYS_REG),
- v2ssMap_(mf.getSSARegMap()->getNumVirtualRegs(), NO_STACK_SLOT) {
- }
-
- unsigned getPhys(unsigned virtReg) const {
- assert(MRegisterInfo::isVirtualRegister(virtReg));
- return v2pMap_[toIndex(virtReg)];
- }
-
- void assignVirt2Phys(unsigned virtReg, unsigned physReg) {
- assert(MRegisterInfo::isVirtualRegister(virtReg) &&
- MRegisterInfo::isPhysicalRegister(physReg));
- assert(v2pMap_[toIndex(virtReg)] == NO_PHYS_REG &&
- "attempt to assign physical register to already mapped "
- "virtual register");
- v2pMap_[toIndex(virtReg)] = physReg;
- }
-
- void clearVirtReg(unsigned virtReg) {
- assert(MRegisterInfo::isVirtualRegister(virtReg));
- assert(v2pMap_[toIndex(virtReg)] != NO_PHYS_REG &&
- "attempt to clear a not assigned virtual register");
- v2pMap_[toIndex(virtReg)] = NO_PHYS_REG;
- }
-
- int getStackSlot(unsigned virtReg) const {
- assert(MRegisterInfo::isVirtualRegister(virtReg));
- return v2ssMap_[toIndex(virtReg)];
- }
-
- int assignVirt2StackSlot(unsigned virtReg);
-
- friend std::ostream& operator<<(std::ostream& os, const VirtRegMap& li);
+ class MachineInstr;
+ class MachineFunction;
+ class MachineRegisterInfo;
+ class TargetInstrInfo;
+ class raw_ostream;
+ class SlotIndexes;
+
+ class VirtRegMap : public MachineFunctionPass {
+ public:
+ enum {
+ NO_PHYS_REG = 0,
+ NO_STACK_SLOT = (1L << 30)-1,
+ MAX_STACK_SLOT = (1L << 18)-1
};
- std::ostream& operator<<(std::ostream& os, const VirtRegMap& li);
-
+ private:
+ MachineRegisterInfo *MRI;
+ const TargetInstrInfo *TII;
+ const TargetRegisterInfo *TRI;
+ 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;
+
+ /// Virt2SplitMap - This is virtual register to splitted virtual register
+ /// mapping.
+ IndexedMap<unsigned, VirtReg2IndexFunctor> Virt2SplitMap;
+
+ /// createSpillSlot - Allocate a spill slot for RC from MFI.
+ unsigned createSpillSlot(const TargetRegisterClass *RC);
+
+ 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), Virt2SplitMap(0) { }
+ virtual bool runOnMachineFunction(MachineFunction &MF);
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesAll();
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
+
+ MachineFunction &getMachineFunction() const {
+ assert(MF && "getMachineFunction called before runOnMachineFunction");
+ return *MF;
+ }
+
+ MachineRegisterInfo &getRegInfo() const { return *MRI; }
+ const TargetRegisterInfo &getTargetRegInfo() const { return *TRI; }
+
+ 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 returns the register allocation preference.
+ unsigned getRegAllocPref(unsigned virtReg);
+
+ /// @brief returns true if VirtReg is assigned to its preferred physreg.
+ bool hasPreferredPhys(unsigned VirtReg) {
+ return getPhys(VirtReg) == getRegAllocPref(VirtReg);
+ }
+
+ /// @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) const {
+ return Virt2SplitMap[virtReg];
+ }
+
+ /// getOriginal - Return the original virtual register that VirtReg descends
+ /// from through splitting.
+ /// A register that was not created by splitting is its own original.
+ /// This operation is idempotent.
+ unsigned getOriginal(unsigned VirtReg) const {
+ unsigned Orig = getPreSplitReg(VirtReg);
+ return Orig ? Orig : 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)
+ 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 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);
+
+ void print(raw_ostream &OS, const Module* M = 0) const;
+ void dump() const;
+ };
+
+ inline raw_ostream &operator<<(raw_ostream &OS, const VirtRegMap &VRM) {
+ VRM.print(OS);
+ return OS;
+ }
} // End llvm namespace
#endif