//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "stackcoloring"
-#include "VirtRegMap.h"
-#include "llvm/Function.h"
-#include "llvm/Module.h"
#include "llvm/CodeGen/Passes.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/LiveStackAnalysis.h"
+#include "llvm/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
-#include "llvm/CodeGen/MachineLoopInfo.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
+#include "llvm/IR/Module.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Target/TargetMachine.h"
-#include "llvm/ADT/BitVector.h"
-#include "llvm/ADT/SmallSet.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/Statistic.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
#include <vector>
using namespace llvm;
+#define DEBUG_TYPE "stackslotcoloring"
+
static cl::opt<bool>
DisableSharing("no-stack-slot-sharing",
cl::init(false), cl::Hidden,
namespace {
class StackSlotColoring : public MachineFunctionPass {
- bool ColorWithRegs;
LiveStacks* LS;
MachineFrameInfo *MFI;
const TargetInstrInfo *TII;
- const MachineLoopInfo *loopInfo;
+ const MachineBlockFrequencyInfo *MBFI;
// SSIntervals - Spill slot intervals.
std::vector<LiveInterval*> SSIntervals;
- // SSRefs - Keep a list of frame index references for each spill slot.
- SmallVector<SmallVector<MachineInstr*, 8>, 16> SSRefs;
+ // SSRefs - Keep a list of MachineMemOperands for each spill slot.
+ // MachineMemOperands can be shared between instructions, so we need
+ // to be careful that renames like [FI0, FI1] -> [FI1, FI2] do not
+ // become FI0 -> FI1 -> FI2.
+ SmallVector<SmallVector<MachineMemOperand *, 8>, 16> SSRefs;
// OrigAlignments - Alignments of stack objects before coloring.
SmallVector<unsigned, 16> OrigAlignments;
public:
static char ID; // Pass identification
StackSlotColoring() :
- MachineFunctionPass(ID), ColorWithRegs(false), NextColor(-1) {
+ MachineFunctionPass(ID), NextColor(-1) {
initializeStackSlotColoringPass(*PassRegistry::getPassRegistry());
}
- StackSlotColoring(bool RegColor) :
- MachineFunctionPass(ID), ColorWithRegs(RegColor), NextColor(-1) {
- initializeStackSlotColoringPass(*PassRegistry::getPassRegistry());
- }
-
- virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.setPreservesCFG();
AU.addRequired<SlotIndexes>();
AU.addPreserved<SlotIndexes>();
AU.addRequired<LiveStacks>();
- AU.addRequired<VirtRegMap>();
- AU.addPreserved<VirtRegMap>();
- AU.addRequired<MachineLoopInfo>();
- AU.addPreserved<MachineLoopInfo>();
+ AU.addRequired<MachineBlockFrequencyInfo>();
+ AU.addPreserved<MachineBlockFrequencyInfo>();
AU.addPreservedID(MachineDominatorsID);
MachineFunctionPass::getAnalysisUsage(AU);
}
- virtual bool runOnMachineFunction(MachineFunction &MF);
- virtual const char* getPassName() const {
- return "Stack Slot Coloring";
- }
+ bool runOnMachineFunction(MachineFunction &MF) override;
private:
void InitializeSlots();
bool OverlapWithAssignments(LiveInterval *li, int Color) const;
int ColorSlot(LiveInterval *li);
bool ColorSlots(MachineFunction &MF);
- void RewriteInstruction(MachineInstr *MI, int OldFI, int NewFI,
+ void RewriteInstruction(MachineInstr *MI, SmallVectorImpl<int> &SlotMapping,
MachineFunction &MF);
bool RemoveDeadStores(MachineBasicBlock* MBB);
};
} // end anonymous namespace
char StackSlotColoring::ID = 0;
+char &llvm::StackSlotColoringID = StackSlotColoring::ID;
INITIALIZE_PASS_BEGIN(StackSlotColoring, "stack-slot-coloring",
"Stack Slot Coloring", false, false)
INITIALIZE_PASS_DEPENDENCY(SlotIndexes)
INITIALIZE_PASS_DEPENDENCY(LiveStacks)
-INITIALIZE_PASS_DEPENDENCY(VirtRegMap)
INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
INITIALIZE_PASS_END(StackSlotColoring, "stack-slot-coloring",
"Stack Slot Coloring", false, false)
-FunctionPass *llvm::createStackSlotColoringPass(bool RegColor) {
- return new StackSlotColoring(RegColor);
-}
-
namespace {
// IntervalSorter - Comparison predicate that sort live intervals by
// their weight.
for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end();
MBBI != E; ++MBBI) {
MachineBasicBlock *MBB = &*MBBI;
- unsigned loopDepth = loopInfo->getLoopDepth(MBB);
for (MachineBasicBlock::iterator MII = MBB->begin(), EE = MBB->end();
MII != EE; ++MII) {
MachineInstr *MI = &*MII;
continue;
LiveInterval &li = LS->getInterval(FI);
if (!MI->isDebugValue())
- li.weight += LiveIntervals::getSpillWeight(false, true, loopDepth);
- SSRefs[FI].push_back(MI);
+ li.weight += LiveIntervals::getSpillWeight(false, true, MBFI, MI);
+ }
+ for (MachineInstr::mmo_iterator MMOI = MI->memoperands_begin(),
+ EE = MI->memoperands_end(); MMOI != EE; ++MMOI) {
+ MachineMemOperand *MMO = *MMOI;
+ if (const FixedStackPseudoSourceValue *FSV =
+ dyn_cast_or_null<FixedStackPseudoSourceValue>(
+ MMO->getPseudoValue())) {
+ int FI = FSV->getFrameIndex();
+ if (FI >= 0)
+ SSRefs[FI].push_back(MMO);
+ }
}
}
}
/// LiveIntervals that have already been assigned to the specified color.
bool
StackSlotColoring::OverlapWithAssignments(LiveInterval *li, int Color) const {
- const SmallVector<LiveInterval*,4> &OtherLIs = Assignments[Color];
+ const SmallVectorImpl<LiveInterval *> &OtherLIs = Assignments[Color];
for (unsigned i = 0, e = OtherLIs.size(); i != e; ++i) {
LiveInterval *OtherLI = OtherLIs[i];
if (OtherLI->overlaps(*li))
if (!Changed)
return false;
- // Rewrite all MO_FrameIndex operands.
- SmallVector<SmallSet<unsigned, 4>, 4> NewDefs(MF.getNumBlockIDs());
+ // Rewrite all MachineMemOperands.
for (unsigned SS = 0, SE = SSRefs.size(); SS != SE; ++SS) {
int NewFI = SlotMapping[SS];
if (NewFI == -1 || (NewFI == (int)SS))
continue;
- SmallVector<MachineInstr*, 8> &RefMIs = SSRefs[SS];
- for (unsigned i = 0, e = RefMIs.size(); i != e; ++i)
- RewriteInstruction(RefMIs[i], SS, NewFI, MF);
+ const PseudoSourceValue *NewSV = PseudoSourceValue::getFixedStack(NewFI);
+ SmallVectorImpl<MachineMemOperand *> &RefMMOs = SSRefs[SS];
+ for (unsigned i = 0, e = RefMMOs.size(); i != e; ++i)
+ RefMMOs[i]->setValue(NewSV);
+ }
+
+ // Rewrite all MO_FrameIndex operands. Look for dead stores.
+ for (MachineFunction::iterator MBBI = MF.begin(), E = MF.end();
+ MBBI != E; ++MBBI) {
+ MachineBasicBlock *MBB = &*MBBI;
+ for (MachineBasicBlock::iterator MII = MBB->begin(), EE = MBB->end();
+ MII != EE; ++MII)
+ RewriteInstruction(MII, SlotMapping, MF);
+ RemoveDeadStores(MBB);
}
// Delete unused stack slots.
/// RewriteInstruction - Rewrite specified instruction by replacing references
/// to old frame index with new one.
-void StackSlotColoring::RewriteInstruction(MachineInstr *MI, int OldFI,
- int NewFI, MachineFunction &MF) {
+void StackSlotColoring::RewriteInstruction(MachineInstr *MI,
+ SmallVectorImpl<int> &SlotMapping,
+ MachineFunction &MF) {
// Update the operands.
for (unsigned i = 0, ee = MI->getNumOperands(); i != ee; ++i) {
MachineOperand &MO = MI->getOperand(i);
if (!MO.isFI())
continue;
- int FI = MO.getIndex();
- if (FI != OldFI)
+ int OldFI = MO.getIndex();
+ if (OldFI < 0)
+ continue;
+ int NewFI = SlotMapping[OldFI];
+ if (NewFI == -1 || NewFI == OldFI)
continue;
MO.setIndex(NewFI);
}
- // Update the memory references. This changes the MachineMemOperands
- // directly. They may be in use by multiple instructions, however all
- // instructions using OldFI are being rewritten to use NewFI.
- const Value *OldSV = PseudoSourceValue::getFixedStack(OldFI);
- const Value *NewSV = PseudoSourceValue::getFixedStack(NewFI);
- for (MachineInstr::mmo_iterator I = MI->memoperands_begin(),
- E = MI->memoperands_end(); I != E; ++I)
- if ((*I)->getValue() == OldSV)
- (*I)->setValue(NewSV);
+ // The MachineMemOperands have already been updated.
}
I != E; ++I) {
if (DCELimit != -1 && (int)NumDead >= DCELimit)
break;
-
- MachineBasicBlock::iterator NextMI = llvm::next(I);
- if (NextMI == MBB->end()) continue;
-
+
int FirstSS, SecondSS;
+ if (TII->isStackSlotCopy(I, FirstSS, SecondSS) &&
+ FirstSS == SecondSS &&
+ FirstSS != -1) {
+ ++NumDead;
+ changed = true;
+ toErase.push_back(I);
+ continue;
+ }
+
+ MachineBasicBlock::iterator NextMI = std::next(I);
+ if (NextMI == MBB->end()) continue;
+
unsigned LoadReg = 0;
unsigned StoreReg = 0;
if (!(LoadReg = TII->isLoadFromStackSlot(I, FirstSS))) continue;
if (!(StoreReg = TII->isStoreToStackSlot(NextMI, SecondSS))) continue;
if (FirstSS != SecondSS || LoadReg != StoreReg || FirstSS == -1) continue;
-
+
++NumDead;
changed = true;
-
- if (NextMI->findRegisterUseOperandIdx(LoadReg, true, 0) != -1) {
+
+ if (NextMI->findRegisterUseOperandIdx(LoadReg, true, nullptr) != -1) {
++NumDead;
toErase.push_back(I);
}
-
+
toErase.push_back(NextMI);
++I;
}
-
- for (SmallVector<MachineInstr*, 4>::iterator I = toErase.begin(),
+
+ for (SmallVectorImpl<MachineInstr *>::iterator I = toErase.begin(),
E = toErase.end(); I != E; ++I)
(*I)->eraseFromParent();
-
+
return changed;
}
bool StackSlotColoring::runOnMachineFunction(MachineFunction &MF) {
DEBUG({
dbgs() << "********** Stack Slot Coloring **********\n"
- << "********** Function: "
- << MF.getFunction()->getName() << '\n';
+ << "********** Function: " << MF.getName() << '\n';
});
MFI = MF.getFrameInfo();
- TII = MF.getTarget().getInstrInfo();
+ TII = MF.getSubtarget().getInstrInfo();
LS = &getAnalysis<LiveStacks>();
- loopInfo = &getAnalysis<MachineLoopInfo>();
+ MBFI = &getAnalysis<MachineBlockFrequencyInfo>();
bool Changed = false;
// coloring. The stack could be modified before the longjmp is executed,
// resulting in the wrong value being used afterwards. (See
// <rdar://problem/8007500>.)
- if (MF.callsSetJmp())
+ if (MF.exposesReturnsTwice())
return false;
// Gather spill slot references
Assignments[i].clear();
Assignments.clear();
- if (Changed) {
- for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I)
- Changed |= RemoveDeadStores(I);
- }
-
return Changed;
}