Teach spiller to unfold instructions which modref spill slot when a scratch
register is available and when it's profitable.
e.g.
xorq %r12<kill>, %r13
addq %rax, -184(%rbp)
addq %r13, -184(%rbp)
==>
xorq %r12<kill>, %r13
movq -184(%rbp), %r12
addq %rax, %r12
addq %r13, %r12
movq %r12, -184(%rbp)
Two more instructions, but fewer memory accesses. It can also open up
opportunities for more optimizations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@69341 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/Spiller.h b/lib/CodeGen/Spiller.h
index 5a42a82..c0d0837 100644
--- a/lib/CodeGen/Spiller.h
+++ b/lib/CodeGen/Spiller.h
@@ -97,7 +97,7 @@
const TargetRegisterInfo *getRegInfo() const { return TRI; }
/// getSpillSlotOrReMatPhysReg - If the specified stack slot or remat is
- /// available in a physical register, return that PhysReg, otherwise
+ /// available in a physical register, return that PhysReg, otherwise
/// return 0.
unsigned getSpillSlotOrReMatPhysReg(int Slot) const {
std::map<int, unsigned>::const_iterator I =
@@ -284,6 +284,7 @@
MachineRegisterInfo *RegInfo;
const TargetRegisterInfo *TRI;
const TargetInstrInfo *TII;
+ BitVector AllocatableRegs;
DenseMap<MachineInstr*, unsigned> DistanceMap;
public:
bool runOnMachineFunction(MachineFunction &MF, VirtRegMap &VRM);
@@ -291,12 +292,22 @@
void TransferDeadness(MachineBasicBlock *MBB, unsigned CurDist,
unsigned Reg, BitVector &RegKills,
std::vector<MachineOperand*> &KillOps);
- bool PrepForUnfoldOpti(MachineBasicBlock &MBB,
- MachineBasicBlock::iterator &MII,
+
+ bool OptimizeByUnfold(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MII,
+ std::vector<MachineInstr*> &MaybeDeadStores,
+ AvailableSpills &Spills, BitVector &RegKills,
+ std::vector<MachineOperand*> &KillOps,
+ VirtRegMap &VRM);
+
+ bool OptimizeByUnfold2(unsigned VirtReg, int SS,
+ MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator &MII,
std::vector<MachineInstr*> &MaybeDeadStores,
AvailableSpills &Spills, BitVector &RegKills,
std::vector<MachineOperand*> &KillOps,
VirtRegMap &VRM);
+
bool CommuteToFoldReload(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MII,
unsigned VirtReg, unsigned SrcReg, int SS,
@@ -305,6 +316,7 @@
std::vector<MachineOperand*> &KillOps,
const TargetRegisterInfo *TRI,
VirtRegMap &VRM);
+
void SpillRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MII,
int Idx, unsigned PhysReg, int StackSlot,
@@ -315,6 +327,7 @@
BitVector &RegKills,
std::vector<MachineOperand*> &KillOps,
VirtRegMap &VRM);
+
void RewriteMBB(MachineBasicBlock &MBB, VirtRegMap &VRM,
AvailableSpills &Spills,
BitVector &RegKills, std::vector<MachineOperand*> &KillOps);