mirror of
https://github.com/RPCSX/llvm.git
synced 2024-11-26 21:20:37 +00:00
Add SplitEditor to SplitKit. This class will be used to edit live intervals and
rewrite instructions for live range splitting. Still work in progress. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109469 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen
parent
3eca15bdb5
commit
f0179004e9
@ -110,8 +110,8 @@ bool InlineSpiller::split() {
|
||||
splitAnalysis_.analyze(li_);
|
||||
|
||||
if (const MachineLoop *loop = splitAnalysis_.getBestSplitLoop()) {
|
||||
if (splitAroundLoop(splitAnalysis_, loop))
|
||||
return true;
|
||||
SplitEditor(splitAnalysis_, lis_, vrm_).splitAroundLoop(loop);
|
||||
return true;
|
||||
}
|
||||
return false;
|
||||
}
|
||||
|
||||
@ -14,8 +14,10 @@
|
||||
|
||||
#define DEBUG_TYPE "splitter"
|
||||
#include "SplitKit.h"
|
||||
#include "VirtRegMap.h"
|
||||
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
|
||||
#include "llvm/CodeGen/MachineFunctionPass.h"
|
||||
#include "llvm/CodeGen/MachineInstrBuilder.h"
|
||||
#include "llvm/CodeGen/MachineLoopInfo.h"
|
||||
#include "llvm/CodeGen/MachineRegisterInfo.h"
|
||||
#include "llvm/Support/CommandLine.h"
|
||||
@ -47,6 +49,7 @@ void SplitAnalysis::clear() {
|
||||
usingInstrs_.clear();
|
||||
usingBlocks_.clear();
|
||||
usingLoops_.clear();
|
||||
curli_ = 0;
|
||||
}
|
||||
|
||||
bool SplitAnalysis::canAnalyzeBranch(const MachineBasicBlock *MBB) {
|
||||
@ -268,11 +271,216 @@ const MachineLoop *SplitAnalysis::getBestSplitLoop() {
|
||||
return Best;
|
||||
}
|
||||
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
// Split Editor
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
/// Create a new SplitEditor for editing the LiveInterval analyzed by SA.
|
||||
SplitEditor::SplitEditor(SplitAnalysis &sa, LiveIntervals &lis, VirtRegMap &vrm)
|
||||
: sa_(sa), lis_(lis), vrm_(vrm),
|
||||
mri_(vrm.getMachineFunction().getRegInfo()),
|
||||
tii_(*vrm.getMachineFunction().getTarget().getInstrInfo()),
|
||||
dupli_(0), openli_(0)
|
||||
{
|
||||
const LiveInterval *curli = sa_.getCurLI();
|
||||
assert(curli && "SplitEditor created from empty SplitAnalysis");
|
||||
|
||||
// Make sure curli is assigned a stack slot, so all our intervals get the
|
||||
// same slot as curli.
|
||||
if (vrm_.getStackSlot(curli->reg) == VirtRegMap::NO_STACK_SLOT)
|
||||
vrm_.assignVirt2StackSlot(curli->reg);
|
||||
|
||||
// Create an interval for dupli that is a copy of curli.
|
||||
dupli_ = createInterval();
|
||||
dupli_->Copy(*curli, &mri_, lis_.getVNInfoAllocator());
|
||||
DEBUG(dbgs() << "SplitEditor DupLI: " << *dupli_ << '\n');
|
||||
}
|
||||
|
||||
LiveInterval *SplitEditor::createInterval() {
|
||||
unsigned curli = sa_.getCurLI()->reg;
|
||||
unsigned Reg = mri_.createVirtualRegister(mri_.getRegClass(curli));
|
||||
LiveInterval &Intv = lis_.getOrCreateInterval(Reg);
|
||||
vrm_.grow();
|
||||
vrm_.assignVirt2StackSlot(Reg, vrm_.getStackSlot(curli));
|
||||
return &Intv;
|
||||
}
|
||||
|
||||
VNInfo *SplitEditor::mapValue(VNInfo *dupliVNI) {
|
||||
VNInfo *&VNI = valueMap_[dupliVNI];
|
||||
if (!VNI)
|
||||
VNI = openli_->createValueCopy(dupliVNI, lis_.getVNInfoAllocator());
|
||||
return VNI;
|
||||
}
|
||||
|
||||
/// Create a new virtual register and live interval to be used by following
|
||||
/// use* and copy* calls.
|
||||
void SplitEditor::openLI() {
|
||||
assert(!openli_ && "Previous LI not closed before openLI");
|
||||
openli_ = createInterval();
|
||||
}
|
||||
|
||||
/// copyToPHI - Insert a copy to openli at the end of A, and catch it with a
|
||||
/// PHI def at the beginning of the successor B. This call is ignored if dupli
|
||||
/// is not live out of A.
|
||||
void SplitEditor::copyToPHI(MachineBasicBlock &A, MachineBasicBlock &B) {
|
||||
assert(openli_ && "openLI not called before copyToPHI");
|
||||
|
||||
SlotIndex EndA = lis_.getMBBEndIdx(&A);
|
||||
VNInfo *DupVNIA = dupli_->getVNInfoAt(EndA.getPrevIndex());
|
||||
if (!DupVNIA) {
|
||||
DEBUG(dbgs() << " ignoring copyToPHI, dupli not live out of BB#"
|
||||
<< A.getNumber() << ".\n");
|
||||
return;
|
||||
}
|
||||
|
||||
// Insert the COPY instruction at the end of A.
|
||||
MachineInstr *MI = BuildMI(A, A.getFirstTerminator(), DebugLoc(),
|
||||
tii_.get(TargetOpcode::COPY), dupli_->reg)
|
||||
.addReg(openli_->reg);
|
||||
SlotIndex DefIdx = lis_.InsertMachineInstrInMaps(MI).getDefIndex();
|
||||
|
||||
// Add a phi kill value and live range out of A.
|
||||
VNInfo *VNIA = openli_->getNextValue(DefIdx, MI, true,
|
||||
lis_.getVNInfoAllocator());
|
||||
openli_->addRange(LiveRange(DefIdx, EndA, VNIA));
|
||||
|
||||
// Now look at the start of B.
|
||||
SlotIndex StartB = lis_.getMBBStartIdx(&B);
|
||||
SlotIndex EndB = lis_.getMBBEndIdx(&B);
|
||||
LiveRange *DupB = dupli_->getLiveRangeContaining(StartB);
|
||||
if (!DupB) {
|
||||
DEBUG(dbgs() << " copyToPHI:, dupli not live in to BB#"
|
||||
<< B.getNumber() << ".\n");
|
||||
return;
|
||||
}
|
||||
|
||||
VNInfo *VNIB = openli_->getVNInfoAt(StartB);
|
||||
if (!VNIB) {
|
||||
// Create a phi value.
|
||||
VNIB = openli_->getNextValue(SlotIndex(StartB, true), 0, false,
|
||||
lis_.getVNInfoAllocator());
|
||||
VNIB->setIsPHIDef(true);
|
||||
// Add a minimal range for the new value.
|
||||
openli_->addRange(LiveRange(VNIB->def, std::min(EndB, DupB->end), VNIB));
|
||||
|
||||
VNInfo *&mapVNI = valueMap_[DupB->valno];
|
||||
if (mapVNI) {
|
||||
// Multiple copies - must create PHI value.
|
||||
abort();
|
||||
} else {
|
||||
// This is the first copy of dupLR. Mark the mapping.
|
||||
mapVNI = VNIB;
|
||||
}
|
||||
|
||||
}
|
||||
|
||||
DEBUG(dbgs() << " copyToPHI at " << DefIdx << ": " << *openli_ << '\n');
|
||||
}
|
||||
|
||||
/// useLI - indicate that all instructions in MBB should use openli.
|
||||
void SplitEditor::useLI(const MachineBasicBlock &MBB) {
|
||||
useLI(lis_.getMBBStartIdx(&MBB), lis_.getMBBEndIdx(&MBB));
|
||||
}
|
||||
|
||||
void SplitEditor::useLI(SlotIndex Start, SlotIndex End) {
|
||||
assert(openli_ && "openLI not called before useLI");
|
||||
|
||||
// Map the dupli values from the interval into openli_
|
||||
LiveInterval::const_iterator B = dupli_->begin(), E = dupli_->end();
|
||||
LiveInterval::const_iterator I = std::lower_bound(B, E, Start);
|
||||
|
||||
if (I != B) {
|
||||
--I;
|
||||
// I begins before Start, but overlaps. openli may already have a value from
|
||||
// copyToLI.
|
||||
if (I->end > Start && !openli_->liveAt(Start))
|
||||
openli_->addRange(LiveRange(Start, std::min(End, I->end),
|
||||
mapValue(I->valno)));
|
||||
++I;
|
||||
}
|
||||
|
||||
// The remaining ranges begin after Start.
|
||||
for (;I != E && I->start < End; ++I)
|
||||
openli_->addRange(LiveRange(I->start, std::min(End, I->end),
|
||||
mapValue(I->valno)));
|
||||
DEBUG(dbgs() << " added range [" << Start << ';' << End << "): " << *openli_
|
||||
<< '\n');
|
||||
}
|
||||
|
||||
/// copyFromLI - Insert a copy back to dupli from openli at position I.
|
||||
SlotIndex SplitEditor::copyFromLI(MachineBasicBlock &MBB, MachineBasicBlock::iterator I) {
|
||||
assert(openli_ && "openLI not called before copyFromLI");
|
||||
|
||||
// Insert the COPY instruction.
|
||||
MachineInstr *MI =
|
||||
BuildMI(MBB, I, DebugLoc(), tii_.get(TargetOpcode::COPY), openli_->reg)
|
||||
.addReg(dupli_->reg);
|
||||
SlotIndex Idx = lis_.InsertMachineInstrInMaps(MI);
|
||||
|
||||
DEBUG(dbgs() << " copyFromLI at " << Idx << ": " << *openli_ << '\n');
|
||||
return Idx;
|
||||
}
|
||||
|
||||
/// closeLI - Indicate that we are done editing the currently open
|
||||
/// LiveInterval, and ranges can be trimmed.
|
||||
void SplitEditor::closeLI() {
|
||||
assert(openli_ && "openLI not called before closeLI");
|
||||
openli_ = 0;
|
||||
}
|
||||
|
||||
/// rewrite - after all the new live ranges have been created, rewrite
|
||||
/// instructions using curli to use the new intervals.
|
||||
void SplitEditor::rewrite() {
|
||||
assert(!openli_ && "Previous LI not closed before rewrite");
|
||||
}
|
||||
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
// Loop Splitting
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
bool llvm::splitAroundLoop(SplitAnalysis &sa, const MachineLoop *loop) {
|
||||
return false;
|
||||
void SplitEditor::splitAroundLoop(const MachineLoop *Loop) {
|
||||
SplitAnalysis::LoopBlocks Blocks;
|
||||
sa_.getLoopBlocks(Loop, Blocks);
|
||||
|
||||
// Break critical edges as needed.
|
||||
SplitAnalysis::BlockPtrSet CriticalExits;
|
||||
sa_.getCriticalExits(Blocks, CriticalExits);
|
||||
assert(CriticalExits.empty() && "Cannot break critical exits yet");
|
||||
|
||||
// Create new live interval for the loop.
|
||||
openLI();
|
||||
|
||||
// Insert copies in the predecessors.
|
||||
for (SplitAnalysis::BlockPtrSet::iterator I = Blocks.Preds.begin(),
|
||||
E = Blocks.Preds.end(); I != E; ++I) {
|
||||
MachineBasicBlock &MBB = const_cast<MachineBasicBlock&>(**I);
|
||||
copyToPHI(MBB, *Loop->getHeader());
|
||||
}
|
||||
|
||||
// Switch all loop blocks.
|
||||
for (SplitAnalysis::BlockPtrSet::iterator I = Blocks.Loop.begin(),
|
||||
E = Blocks.Loop.end(); I != E; ++I)
|
||||
useLI(**I);
|
||||
|
||||
// Insert back copies in the exit blocks.
|
||||
for (SplitAnalysis::BlockPtrSet::iterator I = Blocks.Exits.begin(),
|
||||
E = Blocks.Exits.end(); I != E; ++I) {
|
||||
MachineBasicBlock &MBB = const_cast<MachineBasicBlock&>(**I);
|
||||
SlotIndex Start = lis_.getMBBStartIdx(&MBB);
|
||||
VNInfo *VNI = sa_.getCurLI()->getVNInfoAt(Start);
|
||||
// Only insert a back copy if curli is live and is either a phi or a value
|
||||
// defined inside the loop.
|
||||
if (!VNI) continue;
|
||||
if (openli_->liveAt(VNI->def) ||
|
||||
(VNI->isPHIDef() && VNI->def.getBaseIndex() == Start))
|
||||
copyFromLI(MBB, MBB.begin());
|
||||
}
|
||||
|
||||
// Done.
|
||||
closeLI();
|
||||
rewrite();
|
||||
abort();
|
||||
}
|
||||
|
||||
|
||||
@ -14,19 +14,22 @@
|
||||
|
||||
#include "llvm/ADT/SmallPtrSet.h"
|
||||
#include "llvm/ADT/DenseMap.h"
|
||||
#include "llvm/CodeGen/SlotIndexes.h"
|
||||
|
||||
namespace llvm {
|
||||
|
||||
class LiveInterval;
|
||||
class LiveIntervals;
|
||||
class MachineBasicBlock;
|
||||
class MachineInstr;
|
||||
class MachineFunction;
|
||||
class MachineFunctionPass;
|
||||
class MachineLoop;
|
||||
class MachineLoopInfo;
|
||||
class MachineRegisterInfo;
|
||||
class TargetInstrInfo;
|
||||
class VirtRegMap;
|
||||
class VNInfo;
|
||||
|
||||
/// SplitAnalysis - Analyze a LiveInterval, looking for live range splitting
|
||||
/// opportunities.
|
||||
class SplitAnalysis {
|
||||
const MachineFunction &mf_;
|
||||
const LiveIntervals &lis_;
|
||||
@ -63,6 +66,8 @@ public:
|
||||
/// split.
|
||||
void analyze(const LiveInterval *li);
|
||||
|
||||
const LiveInterval *getCurLI() { return curli_; }
|
||||
|
||||
/// clear - clear all data structures so SplitAnalysis is ready to analyze a
|
||||
/// new interval.
|
||||
void clear();
|
||||
@ -113,8 +118,85 @@ public:
|
||||
const MachineLoop *getBestSplitLoop();
|
||||
};
|
||||
|
||||
/// splitAroundLoop - Try to split curli into a separate live interval inside
|
||||
/// the loop. Retun true on success.
|
||||
bool splitAroundLoop(SplitAnalysis&, const MachineLoop*);
|
||||
/// SplitEditor - Edit machine code and LiveIntervals for live range
|
||||
/// splitting.
|
||||
///
|
||||
/// 1. Create a SplitEditor from a SplitAnalysis. This will create a new
|
||||
/// LiveInterval, dupli, that is identical to SA.curli.
|
||||
/// 2. Start a new live interval with openLI.
|
||||
/// 3. Insert copies to the new interval with copyTo* and mark the ranges where
|
||||
/// it should be used with use*.
|
||||
/// 4. Insert back-copies with copyFromLI.
|
||||
/// 5. Finish the current LI with closeLI and repeat from 2.
|
||||
/// 6. Rewrite instructions with rewrite().
|
||||
///
|
||||
class SplitEditor {
|
||||
SplitAnalysis &sa_;
|
||||
LiveIntervals &lis_;
|
||||
VirtRegMap &vrm_;
|
||||
MachineRegisterInfo &mri_;
|
||||
const TargetInstrInfo &tii_;
|
||||
|
||||
/// dupli_ - Created as a copy of sa_.curli_, ranges are carved out as new
|
||||
/// intervals get added through openLI / closeLI.
|
||||
LiveInterval *dupli_;
|
||||
|
||||
/// Currently open LiveInterval.
|
||||
LiveInterval *openli_;
|
||||
|
||||
/// createInterval - Create a new virtual register and LiveInterval with same
|
||||
/// register class and spill slot as curli.
|
||||
LiveInterval *createInterval();
|
||||
|
||||
/// valueMap_ - Map values in dupli to values in openli. These are direct 1-1
|
||||
/// mappings, and do not include values created by inserted copies.
|
||||
DenseMap<VNInfo*,VNInfo*> valueMap_;
|
||||
|
||||
/// mapValue - Return the openli value that corresponds to the given dupli
|
||||
/// value.
|
||||
VNInfo *mapValue(VNInfo *dupliVNI);
|
||||
|
||||
public:
|
||||
/// Create a new SplitEditor for editing the LiveInterval analyzed by SA.
|
||||
SplitEditor(SplitAnalysis&, LiveIntervals&, VirtRegMap&);
|
||||
|
||||
/// getAnalysis - Get the corresponding analysis.
|
||||
SplitAnalysis &getAnalysis() { return sa_; }
|
||||
|
||||
/// Create a new virtual register and live interval to be used by following
|
||||
/// use* and copy* calls.
|
||||
void openLI();
|
||||
|
||||
/// copyToPHI - Insert a copy to openli at the end of A, and catch it with a
|
||||
/// PHI def at the beginning of the successor B. This call is ignored if dupli
|
||||
/// is not live out of A.
|
||||
void copyToPHI(MachineBasicBlock &A, MachineBasicBlock &B);
|
||||
|
||||
/// useLI - indicate that all instructions in MBB should use openli.
|
||||
void useLI(const MachineBasicBlock &MBB);
|
||||
|
||||
/// useLI - indicate that all instructions in range should use openli.
|
||||
void useLI(SlotIndex Start, SlotIndex End);
|
||||
|
||||
/// copyFromLI - Insert a copy back to dupli from openli at position I.
|
||||
/// This also marks the remainder of MBB as not used by openli.
|
||||
SlotIndex copyFromLI(MachineBasicBlock &MBB, MachineBasicBlock::iterator I);
|
||||
|
||||
/// closeLI - Indicate that we are done editing the currently open
|
||||
/// LiveInterval, and ranges can be trimmed.
|
||||
void closeLI();
|
||||
|
||||
/// rewrite - after all the new live ranges have been created, rewrite
|
||||
/// instructions using curli to use the new intervals.
|
||||
void rewrite();
|
||||
|
||||
// ===--- High level methods ---===
|
||||
|
||||
/// splitAroundLoop - Split curli into a separate live interval inside
|
||||
/// the loop.
|
||||
void splitAroundLoop(const MachineLoop*);
|
||||
|
||||
};
|
||||
|
||||
|
||||
}
|
||||
|
||||
@ -152,6 +152,11 @@ namespace llvm {
|
||||
MachineFunctionPass::getAnalysisUsage(AU);
|
||||
}
|
||||
|
||||
MachineFunction &getMachineFunction() const {
|
||||
assert(MF && "getMachineFunction called before runOnMAchineFunction");
|
||||
return *MF;
|
||||
}
|
||||
|
||||
void grow();
|
||||
|
||||
/// @brief returns true if the specified virtual register is
|
||||
|
||||
Loading…
Reference in New Issue
Block a user