//
//===----------------------------------------------------------------------===//
-#define DEBUG_TYPE "slotindexes"
-
#include "llvm/CodeGen/SlotIndexes.h"
+#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
-#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Target/TargetInstrInfo.h"
using namespace llvm;
-
-// Yep - these are thread safe. See the header for details.
-namespace {
-
-
- class EmptyIndexListEntry : public IndexListEntry {
- public:
- EmptyIndexListEntry() : IndexListEntry(EMPTY_KEY) {}
- };
-
- class TombstoneIndexListEntry : public IndexListEntry {
- public:
- TombstoneIndexListEntry() : IndexListEntry(TOMBSTONE_KEY) {}
- };
-
- // The following statics are thread safe. They're read only, and you
- // can't step from them to any other list entries.
- ManagedStatic<EmptyIndexListEntry> IndexListEntryEmptyKey;
- ManagedStatic<TombstoneIndexListEntry> IndexListEntryTombstoneKey;
-}
+#define DEBUG_TYPE "slotindexes"
char SlotIndexes::ID = 0;
-static RegisterPass<SlotIndexes> X("slotindexes", "Slot index numbering");
-
-IndexListEntry* IndexListEntry::getEmptyKeyEntry() {
- return &*IndexListEntryEmptyKey;
-}
-
-IndexListEntry* IndexListEntry::getTombstoneKeyEntry() {
- return &*IndexListEntryTombstoneKey;
-}
+INITIALIZE_PASS(SlotIndexes, "slotindexes",
+ "Slot index numbering", false, false)
+STATISTIC(NumLocalRenum, "Number of local renumberings");
+STATISTIC(NumGlobalRenum, "Number of global renumberings");
void SlotIndexes::getAnalysisUsage(AnalysisUsage &au) const {
au.setPreservesAll();
void SlotIndexes::releaseMemory() {
mi2iMap.clear();
- mbb2IdxMap.clear();
+ MBBRanges.clear();
idx2MBBMap.clear();
- terminatorGaps.clear();
- clearList();
+ indexList.clear();
+ ileAllocator.Reset();
}
bool SlotIndexes::runOnMachineFunction(MachineFunction &fn) {
// iterator in lock-step (though skipping it over indexes which have
// null pointers in the instruction field).
// At each iteration assert that the instruction pointed to in the index
- // is the same one pointed to by the MI iterator. This
+ // is the same one pointed to by the MI iterator. This
// FIXME: This can be simplified. The mi2iMap_, Idx2MBBMap, etc. should
// only need to be set up once after the first numbering is computed.
mf = &fn;
- initList();
// Check that the list contains only the sentinal.
- assert(indexListHead->getNext() == 0 &&
- "Index list non-empty at initial numbering?");
+ assert(indexList.empty() && "Index list non-empty at initial numbering?");
assert(idx2MBBMap.empty() &&
"Index -> MBB mapping non-empty at initial numbering?");
- assert(mbb2IdxMap.empty() &&
+ assert(MBBRanges.empty() &&
"MBB -> Index mapping non-empty at initial numbering?");
assert(mi2iMap.empty() &&
"MachineInstr -> Index mapping non-empty at initial numbering?");
- functionSize = 0;
unsigned index = 0;
+ MBBRanges.resize(mf->getNumBlockIDs());
+ idx2MBBMap.reserve(mf->size());
- push_back(createEntry(0, index));
+ indexList.push_back(createEntry(nullptr, index));
- // Iterate over the the function.
+ // Iterate over the function.
for (MachineFunction::iterator mbbItr = mf->begin(), mbbEnd = mf->end();
mbbItr != mbbEnd; ++mbbItr) {
MachineBasicBlock *mbb = &*mbbItr;
// Insert an index for the MBB start.
- SlotIndex blockStartIndex(back(), SlotIndex::LOAD);
-
- index += SlotIndex::NUM;
+ SlotIndex blockStartIndex(&indexList.back(), SlotIndex::Slot_Block);
for (MachineBasicBlock::iterator miItr = mbb->begin(), miEnd = mbb->end();
miItr != miEnd; ++miItr) {
- MachineInstr *mi = &*miItr;
-
- if (miItr == mbb->getFirstTerminator()) {
- push_back(createEntry(0, index));
- terminatorGaps.insert(
- std::make_pair(mbb, SlotIndex(back(), SlotIndex::PHI_BIT)));
- index += SlotIndex::NUM;
- }
+ MachineInstr *mi = miItr;
+ if (mi->isDebugValue())
+ continue;
// Insert a store index for the instr.
- push_back(createEntry(mi, index));
+ indexList.push_back(createEntry(mi, index += SlotIndex::InstrDist));
// Save this base index in the maps.
- mi2iMap.insert(
- std::make_pair(mi, SlotIndex(back(), SlotIndex::LOAD)));
-
- ++functionSize;
-
- unsigned Slots = mi->getDesc().getNumDefs();
- if (Slots == 0)
- Slots = 1;
-
- index += (Slots + 1) * SlotIndex::NUM;
+ mi2iMap.insert(std::make_pair(mi, SlotIndex(&indexList.back(),
+ SlotIndex::Slot_Block)));
}
- if (mbb->getFirstTerminator() == mbb->end()) {
- push_back(createEntry(0, index));
- terminatorGaps.insert(
- std::make_pair(mbb, SlotIndex(back(), SlotIndex::PHI_BIT)));
- index += SlotIndex::NUM;
- }
-
- // One blank instruction at the end.
- push_back(createEntry(0, index));
-
- SlotIndex blockEndIndex(back(), SlotIndex::LOAD);
- mbb2IdxMap.insert(
- std::make_pair(mbb, std::make_pair(blockStartIndex, blockEndIndex)));
+ // We insert one blank instructions between basic blocks.
+ indexList.push_back(createEntry(nullptr, index += SlotIndex::InstrDist));
+ MBBRanges[mbb->getNumber()].first = blockStartIndex;
+ MBBRanges[mbb->getNumber()].second = SlotIndex(&indexList.back(),
+ SlotIndex::Slot_Block);
idx2MBBMap.push_back(IdxMBBPair(blockStartIndex, mbb));
}
// Sort the Idx2MBBMap
std::sort(idx2MBBMap.begin(), idx2MBBMap.end(), Idx2MBBCompare());
- DEBUG(dump());
+ DEBUG(mf->print(dbgs(), this));
// And we're done!
return false;
}
void SlotIndexes::renumberIndexes() {
-
// Renumber updates the index of every element of the index list.
- // If all instrs in the function have been allocated an index (which has been
- // placed in the index list in the order of instruction iteration) then the
- // resulting numbering will match what would have been generated by the
- // pass during the initial numbering of the function if the new instructions
- // had been present.
+ DEBUG(dbgs() << "\n*** Renumbering SlotIndexes ***\n");
+ ++NumGlobalRenum;
- functionSize = 0;
unsigned index = 0;
- for (IndexListEntry *curEntry = front(); curEntry != getTail();
- curEntry = curEntry->getNext()) {
+ for (IndexList::iterator I = indexList.begin(), E = indexList.end();
+ I != E; ++I) {
+ I->setIndex(index);
+ index += SlotIndex::InstrDist;
+ }
+}
- curEntry->setIndex(index);
+// Renumber indexes locally after curItr was inserted, but failed to get a new
+// index.
+void SlotIndexes::renumberIndexes(IndexList::iterator curItr) {
+ // Number indexes with half the default spacing so we can catch up quickly.
+ const unsigned Space = SlotIndex::InstrDist/2;
+ static_assert((Space & 3) == 0, "InstrDist must be a multiple of 2*NUM");
+
+ IndexList::iterator startItr = std::prev(curItr);
+ unsigned index = startItr->getIndex();
+ do {
+ curItr->setIndex(index += Space);
+ ++curItr;
+ // If the next index is bigger, we have caught up.
+ } while (curItr != indexList.end() && curItr->getIndex() <= index);
+
+ DEBUG(dbgs() << "\n*** Renumbered SlotIndexes " << startItr->getIndex() << '-'
+ << index << " ***\n");
+ ++NumLocalRenum;
+}
- if (curEntry->getInstr() == 0) {
- // MBB start entry or terminator gap. Just step index by 1.
- index += SlotIndex::NUM;
+// Repair indexes after adding and removing instructions.
+void SlotIndexes::repairIndexesInRange(MachineBasicBlock *MBB,
+ MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End) {
+ // FIXME: Is this really necessary? The only caller repairIntervalsForRange()
+ // does the same thing.
+ // Find anchor points, which are at the beginning/end of blocks or at
+ // instructions that already have indexes.
+ while (Begin != MBB->begin() && !hasIndex(Begin))
+ --Begin;
+ while (End != MBB->end() && !hasIndex(End))
+ ++End;
+
+ bool includeStart = (Begin == MBB->begin());
+ SlotIndex startIdx;
+ if (includeStart)
+ startIdx = getMBBStartIdx(MBB);
+ else
+ startIdx = getInstructionIndex(Begin);
+
+ SlotIndex endIdx;
+ if (End == MBB->end())
+ endIdx = getMBBEndIdx(MBB);
+ else
+ endIdx = getInstructionIndex(End);
+
+ // FIXME: Conceptually, this code is implementing an iterator on MBB that
+ // optionally includes an additional position prior to MBB->begin(), indicated
+ // by the includeStart flag. This is done so that we can iterate MIs in a MBB
+ // in parallel with SlotIndexes, but there should be a better way to do this.
+ IndexList::iterator ListB = startIdx.listEntry();
+ IndexList::iterator ListI = endIdx.listEntry();
+ MachineBasicBlock::iterator MBBI = End;
+ bool pastStart = false;
+ while (ListI != ListB || MBBI != Begin || (includeStart && !pastStart)) {
+ assert(ListI->getIndex() >= startIdx.getIndex() &&
+ (includeStart || !pastStart) &&
+ "Decremented past the beginning of region to repair.");
+
+ MachineInstr *SlotMI = ListI->getInstr();
+ MachineInstr *MI = (MBBI != MBB->end() && !pastStart) ? MBBI : nullptr;
+ bool MBBIAtBegin = MBBI == Begin && (!includeStart || pastStart);
+
+ if (SlotMI == MI && !MBBIAtBegin) {
+ --ListI;
+ if (MBBI != Begin)
+ --MBBI;
+ else
+ pastStart = true;
+ } else if (MI && mi2iMap.find(MI) == mi2iMap.end()) {
+ if (MBBI != Begin)
+ --MBBI;
+ else
+ pastStart = true;
+ } else {
+ --ListI;
+ if (SlotMI)
+ removeMachineInstrFromMaps(SlotMI);
}
- else {
- ++functionSize;
- unsigned Slots = curEntry->getInstr()->getDesc().getNumDefs();
- if (Slots == 0)
- Slots = 1;
+ }
- index += (Slots + 1) * SlotIndex::NUM;
- }
+ // In theory this could be combined with the previous loop, but it is tricky
+ // to update the IndexList while we are iterating it.
+ for (MachineBasicBlock::iterator I = End; I != Begin;) {
+ --I;
+ MachineInstr *MI = I;
+ if (!MI->isDebugValue() && mi2iMap.find(MI) == mi2iMap.end())
+ insertMachineInstrInMaps(MI);
}
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
void SlotIndexes::dump() const {
- for (const IndexListEntry *itr = front(); itr != getTail();
- itr = itr->getNext()) {
+ for (IndexList::const_iterator itr = indexList.begin();
+ itr != indexList.end(); ++itr) {
dbgs() << itr->getIndex() << " ";
- if (itr->getInstr() != 0) {
+ if (itr->getInstr()) {
dbgs() << *itr->getInstr();
} else {
dbgs() << "\n";
}
}
- for (MBB2IdxMap::const_iterator itr = mbb2IdxMap.begin();
- itr != mbb2IdxMap.end(); ++itr) {
- dbgs() << "MBB " << itr->first->getNumber() << " (" << itr->first << ") - ["
- << itr->second.first << ", " << itr->second.second << "]\n";
- }
+ for (unsigned i = 0, e = MBBRanges.size(); i != e; ++i)
+ dbgs() << "BB#" << i << "\t[" << MBBRanges[i].first << ';'
+ << MBBRanges[i].second << ")\n";
}
+#endif
// Print a SlotIndex to a raw_ostream.
void SlotIndex::print(raw_ostream &os) const {
- os << getIndex();
- if (isPHI())
- os << "*";
+ if (isValid())
+ os << listEntry()->getIndex() << "Berd"[getSlot()];
+ else
+ os << "invalid";
}
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
// Dump a SlotIndex to stderr.
void SlotIndex::dump() const {
print(dbgs());
dbgs() << "\n";
}
+#endif