RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-01 16:33:37 +01:00
Code Issues Projects Releases Wiki Activity
fc3e4d63e1
llvm-mirror/include/llvm/CodeGen/SlotIndexes.h
Jakob Stoklund Olesen 8b66caf12a Renumber slot indexes locally when possible. 
Initially, slot indexes are quad-spaced. There is room for inserting up to 3
new instructions between the original instructions.

When we run out of indexes between two instructions, renumber locally using
double-spaced indexes. The original quad-spacing means that we catch up quickly,
and we only have to renumber a handful of instructions to get a monotonic
sequence. This is much faster than renumbering the whole function as we did
before.

llvm-svn: 127023
2011-03-04 19:43:38 +00:00

729 lines
23 KiB
C++
Raw Blame History

//===- llvm/CodeGen/SlotIndexes.h - Slot indexes representation -*- 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 SlotIndex and related classes. The purpuse of SlotIndex
// is to describe a position at which a register can become live, or cease to
// be live.
//
// SlotIndex is mostly a proxy for entries of the SlotIndexList, a class which
// is held is LiveIntervals and provides the real numbering. This allows
// LiveIntervals to perform largely transparent renumbering.
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_SLOTINDEXES_H
#define LLVM_CODEGEN_SLOTINDEXES_H
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/ADT/PointerIntPair.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/Support/Allocator.h"
namespace llvm {
/// This class represents an entry in the slot index list held in the
/// SlotIndexes pass. It should not be used directly. See the
/// SlotIndex & SlotIndexes classes for the public interface to this
/// information.
class IndexListEntry {
IndexListEntry *next, *prev;
MachineInstr *mi;
unsigned index;
public:
IndexListEntry(MachineInstr *mi, unsigned index) : mi(mi), index(index) {}
MachineInstr* getInstr() const { return mi; }
void setInstr(MachineInstr *mi) {
this->mi = mi;
}
unsigned getIndex() const { return index; }
void setIndex(unsigned index) {
this->index = index;
}
IndexListEntry* getNext() { return next; }
const IndexListEntry* getNext() const { return next; }
void setNext(IndexListEntry *next) {
this->next = next;
}
IndexListEntry* getPrev() { return prev; }
const IndexListEntry* getPrev() const { return prev; }
void setPrev(IndexListEntry *prev) {
this->prev = prev;
}
};
// Specialize PointerLikeTypeTraits for IndexListEntry.
template <>
class PointerLikeTypeTraits<IndexListEntry*> {
public:
static inline void* getAsVoidPointer(IndexListEntry *p) {
return p;
}
static inline IndexListEntry* getFromVoidPointer(void *p) {
return static_cast<IndexListEntry*>(p);
}
enum { NumLowBitsAvailable = 3 };
};
/// SlotIndex - An opaque wrapper around machine indexes.
class SlotIndex {
friend class SlotIndexes;
friend struct DenseMapInfo<SlotIndex>;
enum Slot { LOAD, USE, DEF, STORE, NUM };
PointerIntPair<IndexListEntry*, 2, unsigned> lie;
SlotIndex(IndexListEntry *entry, unsigned slot)
: lie(entry, slot) {}
IndexListEntry& entry() const {
assert(isValid() && "Attempt to compare reserved index.");
return *lie.getPointer();
}
int getIndex() const {
return entry().getIndex() | getSlot();
}
/// Returns the slot for this SlotIndex.
Slot getSlot() const {
return static_cast<Slot>(lie.getInt());
}
static inline unsigned getHashValue(const SlotIndex &v) {
void *ptrVal = v.lie.getOpaqueValue();
return (unsigned((intptr_t)ptrVal)) ^ (unsigned((intptr_t)ptrVal) >> 9);
}
public:
enum {
/// The default distance between instructions as returned by distance().
/// This may vary as instructions are inserted and removed.
InstrDist = 4*NUM
};
static inline SlotIndex getEmptyKey() {
return SlotIndex(0, 1);
}
static inline SlotIndex getTombstoneKey() {
return SlotIndex(0, 2);
}
/// Construct an invalid index.
SlotIndex() : lie(0, 0) {}
// Construct a new slot index from the given one, and set the slot.
SlotIndex(const SlotIndex &li, Slot s)
: lie(&li.entry(), unsigned(s)) {
assert(lie.getPointer() != 0 &&
"Attempt to construct index with 0 pointer.");
}
/// Returns true if this is a valid index. Invalid indicies do
/// not point into an index table, and cannot be compared.
bool isValid() const {
return lie.getPointer();
}
/// Print this index to the given raw_ostream.
void print(raw_ostream &os) const;
/// Dump this index to stderr.
void dump() const;
/// Compare two SlotIndex objects for equality.
bool operator==(SlotIndex other) const {
return lie == other.lie;
}
/// Compare two SlotIndex objects for inequality.
bool operator!=(SlotIndex other) const {
return lie != other.lie;
}
/// Compare two SlotIndex objects. Return true if the first index
/// is strictly lower than the second.
bool operator<(SlotIndex other) const {
return getIndex() < other.getIndex();
}
/// Compare two SlotIndex objects. Return true if the first index
/// is lower than, or equal to, the second.
bool operator<=(SlotIndex other) const {
return getIndex() <= other.getIndex();
}
/// Compare two SlotIndex objects. Return true if the first index
/// is greater than the second.
bool operator>(SlotIndex other) const {
return getIndex() > other.getIndex();
}
/// Compare two SlotIndex objects. Return true if the first index
/// is greater than, or equal to, the second.
bool operator>=(SlotIndex other) const {
return getIndex() >= other.getIndex();
}
/// Return the distance from this index to the given one.
int distance(SlotIndex other) const {
return other.getIndex() - getIndex();
}
/// isLoad - Return true if this is a LOAD slot.
bool isLoad() const {
return getSlot() == LOAD;
}
/// isDef - Return true if this is a DEF slot.
bool isDef() const {
return getSlot() == DEF;
}
/// isUse - Return true if this is a USE slot.
bool isUse() const {
return getSlot() == USE;
}
/// isStore - Return true if this is a STORE slot.
bool isStore() const {
return getSlot() == STORE;
}
/// Returns the base index for associated with this index. The base index
/// is the one associated with the LOAD slot for the instruction pointed to
/// by this index.
SlotIndex getBaseIndex() const {
return getLoadIndex();
}
/// Returns the boundary index for associated with this index. The boundary
/// index is the one associated with the LOAD slot for the instruction
/// pointed to by this index.
SlotIndex getBoundaryIndex() const {
return getStoreIndex();
}
/// Returns the index of the LOAD slot for the instruction pointed to by
/// this index.
SlotIndex getLoadIndex() const {
return SlotIndex(&entry(), SlotIndex::LOAD);
}
/// Returns the index of the USE slot for the instruction pointed to by
/// this index.
SlotIndex getUseIndex() const {
return SlotIndex(&entry(), SlotIndex::USE);
}
/// Returns the index of the DEF slot for the instruction pointed to by
/// this index.
SlotIndex getDefIndex() const {
return SlotIndex(&entry(), SlotIndex::DEF);
}
/// Returns the index of the STORE slot for the instruction pointed to by
/// this index.
SlotIndex getStoreIndex() const {
return SlotIndex(&entry(), SlotIndex::STORE);
}
/// Returns the next slot in the index list. This could be either the
/// next slot for the instruction pointed to by this index or, if this
/// index is a STORE, the first slot for the next instruction.
/// WARNING: This method is considerably more expensive than the methods
/// that return specific slots (getUseIndex(), etc). If you can - please
/// use one of those methods.
SlotIndex getNextSlot() const {
Slot s = getSlot();
if (s == SlotIndex::STORE) {
return SlotIndex(entry().getNext(), SlotIndex::LOAD);
}
return SlotIndex(&entry(), s + 1);
}
/// Returns the next index. This is the index corresponding to the this
/// index's slot, but for the next instruction.
SlotIndex getNextIndex() const {
return SlotIndex(entry().getNext(), getSlot());
}
/// Returns the previous slot in the index list. This could be either the
/// previous slot for the instruction pointed to by this index or, if this
/// index is a LOAD, the last slot for the previous instruction.
/// WARNING: This method is considerably more expensive than the methods
/// that return specific slots (getUseIndex(), etc). If you can - please
/// use one of those methods.
SlotIndex getPrevSlot() const {
Slot s = getSlot();
if (s == SlotIndex::LOAD) {
return SlotIndex(entry().getPrev(), SlotIndex::STORE);
}
return SlotIndex(&entry(), s - 1);
}
/// Returns the previous index. This is the index corresponding to this
/// index's slot, but for the previous instruction.
SlotIndex getPrevIndex() const {
return SlotIndex(entry().getPrev(), getSlot());
}
};
/// DenseMapInfo specialization for SlotIndex.
template <>
struct DenseMapInfo<SlotIndex> {
static inline SlotIndex getEmptyKey() {
return SlotIndex::getEmptyKey();
}
static inline SlotIndex getTombstoneKey() {
return SlotIndex::getTombstoneKey();
}
static inline unsigned getHashValue(const SlotIndex &v) {
return SlotIndex::getHashValue(v);
}
static inline bool isEqual(const SlotIndex &LHS, const SlotIndex &RHS) {
return (LHS == RHS);
}
};
template <> struct isPodLike<SlotIndex> { static const bool value = true; };
inline raw_ostream& operator<<(raw_ostream &os, SlotIndex li) {
li.print(os);
return os;
}
typedef std::pair<SlotIndex, MachineBasicBlock*> IdxMBBPair;
inline bool operator<(SlotIndex V, const IdxMBBPair &IM) {
return V < IM.first;
}
inline bool operator<(const IdxMBBPair &IM, SlotIndex V) {
return IM.first < V;
}
struct Idx2MBBCompare {
bool operator()(const IdxMBBPair &LHS, const IdxMBBPair &RHS) const {
return LHS.first < RHS.first;
}
};
/// SlotIndexes pass.
///
/// This pass assigns indexes to each instruction.
class SlotIndexes : public MachineFunctionPass {
private:
MachineFunction *mf;
IndexListEntry *indexListHead;
unsigned functionSize;
typedef DenseMap<const MachineInstr*, SlotIndex> Mi2IndexMap;
Mi2IndexMap mi2iMap;
/// MBB2IdxMap - The indexes of the first and last instructions in the
/// specified basic block.
typedef DenseMap<const MachineBasicBlock*,
std::pair<SlotIndex, SlotIndex> > MBB2IdxMap;
MBB2IdxMap mbb2IdxMap;
/// Idx2MBBMap - Sorted list of pairs of index of first instruction
/// and MBB id.
std::vector<IdxMBBPair> idx2MBBMap;
// IndexListEntry allocator.
BumpPtrAllocator ileAllocator;
IndexListEntry* createEntry(MachineInstr *mi, unsigned index) {
IndexListEntry *entry =
static_cast<IndexListEntry*>(
ileAllocator.Allocate(sizeof(IndexListEntry),
alignOf<IndexListEntry>()));
new (entry) IndexListEntry(mi, index);
return entry;
}
void initList() {
assert(indexListHead == 0 && "Zero entry non-null at initialisation.");
indexListHead = createEntry(0, ~0U);
indexListHead->setNext(0);
indexListHead->setPrev(indexListHead);
}
void clearList() {
indexListHead = 0;
ileAllocator.Reset();
}
IndexListEntry* getTail() {
assert(indexListHead != 0 && "Call to getTail on uninitialized list.");
return indexListHead->getPrev();
}
const IndexListEntry* getTail() const {
assert(indexListHead != 0 && "Call to getTail on uninitialized list.");
return indexListHead->getPrev();
}
// Returns true if the index list is empty.
bool empty() const { return (indexListHead == getTail()); }
IndexListEntry* front() {
assert(!empty() && "front() called on empty index list.");
return indexListHead;
}
const IndexListEntry* front() const {
assert(!empty() && "front() called on empty index list.");
return indexListHead;
}
IndexListEntry* back() {
assert(!empty() && "back() called on empty index list.");
return getTail()->getPrev();
}
const IndexListEntry* back() const {
assert(!empty() && "back() called on empty index list.");
return getTail()->getPrev();
}
/// Insert a new entry before itr.
void insert(IndexListEntry *itr, IndexListEntry *val) {
assert(itr != 0 && "itr should not be null.");
IndexListEntry *prev = itr->getPrev();
val->setNext(itr);
val->setPrev(prev);
if (itr != indexListHead) {
prev->setNext(val);
}
else {
indexListHead = val;
}
itr->setPrev(val);
}
/// Push a new entry on to the end of the list.
void push_back(IndexListEntry *val) {
insert(getTail(), val);
}
/// Renumber locally after inserting newEntry.
void renumberIndexes(IndexListEntry *newEntry);
public:
static char ID;
SlotIndexes() : MachineFunctionPass(ID), indexListHead(0) {
initializeSlotIndexesPass(*PassRegistry::getPassRegistry());
}
virtual void getAnalysisUsage(AnalysisUsage &au) const;
virtual void releaseMemory();
virtual bool runOnMachineFunction(MachineFunction &fn);
/// Dump the indexes.
void dump() const;
/// Renumber the index list, providing space for new instructions.
void renumberIndexes();
/// Returns the zero index for this analysis.
SlotIndex getZeroIndex() {
assert(front()->getIndex() == 0 && "First index is not 0?");
return SlotIndex(front(), 0);
}
/// Returns the base index of the last slot in this analysis.
SlotIndex getLastIndex() {
return SlotIndex(back(), 0);
}
/// Returns the invalid index marker for this analysis.
SlotIndex getInvalidIndex() {
return getZeroIndex();
}
/// Returns the distance between the highest and lowest indexes allocated
/// so far.
unsigned getIndexesLength() const {
assert(front()->getIndex() == 0 &&
"Initial index isn't zero?");
return back()->getIndex();
}
/// Returns the number of instructions in the function.
unsigned getFunctionSize() const {
return functionSize;
}
/// Returns true if the given machine instr is mapped to an index,
/// otherwise returns false.
bool hasIndex(const MachineInstr *instr) const {
return (mi2iMap.find(instr) != mi2iMap.end());
}
/// Returns the base index for the given instruction.
SlotIndex getInstructionIndex(const MachineInstr *instr) const {
Mi2IndexMap::const_iterator itr = mi2iMap.find(instr);
assert(itr != mi2iMap.end() && "Instruction not found in maps.");
return itr->second;
}
/// Returns the instruction for the given index, or null if the given
/// index has no instruction associated with it.
MachineInstr* getInstructionFromIndex(SlotIndex index) const {
return index.isValid() ? index.entry().getInstr() : 0;
}
/// Returns the next non-null index.
SlotIndex getNextNonNullIndex(SlotIndex index) {
SlotIndex nextNonNull = index.getNextIndex();
while (&nextNonNull.entry() != getTail() &&
getInstructionFromIndex(nextNonNull) == 0) {
nextNonNull = nextNonNull.getNextIndex();
}
return nextNonNull;
}
/// Return the (start,end) range of the given basic block.
const std::pair<SlotIndex, SlotIndex> &
getMBBRange(const MachineBasicBlock *mbb) const {
MBB2IdxMap::const_iterator itr = mbb2IdxMap.find(mbb);
assert(itr != mbb2IdxMap.end() && "MBB not found in maps.");
return itr->second;
}
/// Returns the first index in the given basic block.
SlotIndex getMBBStartIdx(const MachineBasicBlock *mbb) const {
return getMBBRange(mbb).first;
}
/// Returns the last index in the given basic block.
SlotIndex getMBBEndIdx(const MachineBasicBlock *mbb) const {
return getMBBRange(mbb).second;
}
/// Returns the basic block which the given index falls in.
MachineBasicBlock* getMBBFromIndex(SlotIndex index) const {
std::vector<IdxMBBPair>::const_iterator I =
std::lower_bound(idx2MBBMap.begin(), idx2MBBMap.end(), index);
// Take the pair containing the index
std::vector<IdxMBBPair>::const_iterator J =
((I != idx2MBBMap.end() && I->first > index) ||
(I == idx2MBBMap.end() && idx2MBBMap.size()>0)) ? (I-1): I;
assert(J != idx2MBBMap.end() && J->first <= index &&
index < getMBBEndIdx(J->second) &&
"index does not correspond to an MBB");
return J->second;
}
bool findLiveInMBBs(SlotIndex start, SlotIndex end,
SmallVectorImpl<MachineBasicBlock*> &mbbs) const {
std::vector<IdxMBBPair>::const_iterator itr =
std::lower_bound(idx2MBBMap.begin(), idx2MBBMap.end(), start);
bool resVal = false;
while (itr != idx2MBBMap.end()) {
if (itr->first >= end)
break;
mbbs.push_back(itr->second);
resVal = true;
++itr;
}
return resVal;
}
/// Returns the MBB covering the given range, or null if the range covers
/// more than one basic block.
MachineBasicBlock* getMBBCoveringRange(SlotIndex start, SlotIndex end) const {
assert(start < end && "Backwards ranges not allowed.");
std::vector<IdxMBBPair>::const_iterator itr =
std::lower_bound(idx2MBBMap.begin(), idx2MBBMap.end(), start);
if (itr == idx2MBBMap.end()) {
itr = prior(itr);
return itr->second;
}
// Check that we don't cross the boundary into this block.
if (itr->first < end)
return 0;
itr = prior(itr);
if (itr->first <= start)
return itr->second;
return 0;
}
/// Insert the given machine instruction into the mapping. Returns the
/// assigned index.
SlotIndex insertMachineInstrInMaps(MachineInstr *mi) {
assert(mi2iMap.find(mi) == mi2iMap.end() && "Instr already indexed.");
// Numbering DBG_VALUE instructions could cause code generation to be
// affected by debug information.
assert(!mi->isDebugValue() && "Cannot number DBG_VALUE instructions.");
MachineBasicBlock *mbb = mi->getParent();
assert(mbb != 0 && "Instr must be added to function.");
MBB2IdxMap::iterator mbbRangeItr = mbb2IdxMap.find(mbb);
assert(mbbRangeItr != mbb2IdxMap.end() &&
"Instruction's parent MBB has not been added to SlotIndexes.");
MachineBasicBlock::iterator miItr(mi);
IndexListEntry *newEntry;
// Get previous index, considering that not all instructions are indexed.
IndexListEntry *prevEntry;
for (;;) {
// If mi is at the mbb beginning, get the prev index from the mbb.
if (miItr == mbb->begin()) {
prevEntry = &mbbRangeItr->second.first.entry();
break;
}
// Otherwise rewind until we find a mapped instruction.
Mi2IndexMap::const_iterator itr = mi2iMap.find(--miItr);
if (itr != mi2iMap.end()) {
prevEntry = &itr->second.entry();
break;
}
}
// Get next entry from previous entry.
IndexListEntry *nextEntry = prevEntry->getNext();
// Get a number for the new instr, or 0 if there's no room currently.
// In the latter case we'll force a renumber later.
unsigned dist = ((nextEntry->getIndex() - prevEntry->getIndex())/2) & ~3u;
unsigned newNumber = prevEntry->getIndex() + dist;
// Insert a new list entry for mi.
newEntry = createEntry(mi, newNumber);
insert(nextEntry, newEntry);
// Renumber locally if we need to.
if (dist == 0)
renumberIndexes(newEntry);
SlotIndex newIndex(newEntry, SlotIndex::LOAD);
mi2iMap.insert(std::make_pair(mi, newIndex));
return newIndex;
}
/// Remove the given machine instruction from the mapping.
void removeMachineInstrFromMaps(MachineInstr *mi) {
// remove index -> MachineInstr and
// MachineInstr -> index mappings
Mi2IndexMap::iterator mi2iItr = mi2iMap.find(mi);
if (mi2iItr != mi2iMap.end()) {
IndexListEntry *miEntry(&mi2iItr->second.entry());
assert(miEntry->getInstr() == mi && "Instruction indexes broken.");
// FIXME: Eventually we want to actually delete these indexes.
miEntry->setInstr(0);
mi2iMap.erase(mi2iItr);
}
}
/// ReplaceMachineInstrInMaps - Replacing a machine instr with a new one in
/// maps used by register allocator.
void replaceMachineInstrInMaps(MachineInstr *mi, MachineInstr *newMI) {
Mi2IndexMap::iterator mi2iItr = mi2iMap.find(mi);
if (mi2iItr == mi2iMap.end())
return;
SlotIndex replaceBaseIndex = mi2iItr->second;
IndexListEntry *miEntry(&replaceBaseIndex.entry());
assert(miEntry->getInstr() == mi &&
"Mismatched instruction in index tables.");
miEntry->setInstr(newMI);
mi2iMap.erase(mi2iItr);
mi2iMap.insert(std::make_pair(newMI, replaceBaseIndex));
}
/// Add the given MachineBasicBlock into the maps.
void insertMBBInMaps(MachineBasicBlock *mbb) {
MachineFunction::iterator nextMBB =
llvm::next(MachineFunction::iterator(mbb));
IndexListEntry *startEntry = createEntry(0, 0);
IndexListEntry *stopEntry = createEntry(0, 0);
IndexListEntry *nextEntry = 0;
if (nextMBB == mbb->getParent()->end()) {
nextEntry = getTail();
} else {
nextEntry = &getMBBStartIdx(nextMBB).entry();
}
insert(nextEntry, startEntry);
insert(nextEntry, stopEntry);
SlotIndex startIdx(startEntry, SlotIndex::LOAD);
SlotIndex endIdx(nextEntry, SlotIndex::LOAD);
mbb2IdxMap.insert(
std::make_pair(mbb, std::make_pair(startIdx, endIdx)));
idx2MBBMap.push_back(IdxMBBPair(startIdx, mbb));
if (MachineFunction::iterator(mbb) != mbb->getParent()->begin()) {
// Have to update the end index of the previous block.
MachineBasicBlock *priorMBB =
llvm::prior(MachineFunction::iterator(mbb));
mbb2IdxMap[priorMBB].second = startIdx;
}
renumberIndexes();
std::sort(idx2MBBMap.begin(), idx2MBBMap.end(), Idx2MBBCompare());
}
};
// Specialize IntervalMapInfo for half-open slot index intervals.
template <typename> struct IntervalMapInfo;
template <> struct IntervalMapInfo<SlotIndex> {
static inline bool startLess(const SlotIndex &x, const SlotIndex &a) {
return x < a;
}
static inline bool stopLess(const SlotIndex &b, const SlotIndex &x) {
return b <= x;
}
static inline bool adjacent(const SlotIndex &a, const SlotIndex &b) {
return a == b;
}
};
}
#endif // LLVM_CODEGEN_LIVEINDEX_H
Reference in New Issue View Git Blame Copy Permalink