// This file implements the LiveRange and LiveInterval classes. Given some
// numbering of each the machine instructions an interval [i, j) is said to be a
// live interval for register v if there is no instruction with number j' > j
-// such that v is live at j' abd there is no instruction with number i' < i such
+// such that v is live at j' and there is no instruction with number i' < i such
// that v is live at i'. In this implementation intervals can have holes,
// i.e. an interval might look like [1,20), [50,65), [1000,1001). Each
// individual range is represented as an instance of LiveRange, and the whole
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/STLExtras.h"
-#include "llvm/Support/Streams.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include <algorithm>
-#include <ostream>
using namespace llvm;
-// An example for liveAt():
-//
-// this = [1,4), liveAt(0) will return false. The instruction defining this
-// spans slots [0,3]. The interval belongs to an spilled definition of the
-// variable it represents. This is because slot 1 is used (def slot) and spans
-// up to slot 3 (store slot).
-//
-bool LiveInterval::liveAt(unsigned I) const {
- Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I);
-
- if (r == ranges.begin())
- return false;
-
- --r;
- return r->contains(I);
+LiveInterval::iterator LiveInterval::find(SlotIndex Pos) {
+ // This algorithm is basically std::upper_bound.
+ // Unfortunately, std::upper_bound cannot be used with mixed types until we
+ // adopt C++0x. Many libraries can do it, but not all.
+ if (empty() || Pos >= endIndex())
+ return end();
+ iterator I = begin();
+ size_t Len = ranges.size();
+ do {
+ size_t Mid = Len >> 1;
+ if (Pos < I[Mid].end)
+ Len = Mid;
+ else
+ I += Mid + 1, Len -= Mid + 1;
+ } while (Len);
+ return I;
}
-// liveBeforeAndAt - Check if the interval is live at the index and the index
-// just before it. If index is liveAt, check if it starts a new live range.
-// If it does, then check if the previous live range ends at index-1.
-bool LiveInterval::liveBeforeAndAt(unsigned I) const {
- Ranges::const_iterator r = std::upper_bound(ranges.begin(), ranges.end(), I);
+/// killedInRange - Return true if the interval has kills in [Start,End).
+bool LiveInterval::killedInRange(SlotIndex Start, SlotIndex End) const {
+ Ranges::const_iterator r =
+ std::lower_bound(ranges.begin(), ranges.end(), End);
+ // Now r points to the first interval with start >= End, or ranges.end().
if (r == ranges.begin())
return false;
--r;
- if (!r->contains(I))
- return false;
- if (I != r->start)
- return true;
- // I is the start of a live range. Check if the previous live range ends
- // at I-1.
- if (r == ranges.begin())
- return false;
- return r->end == I;
+ // Now r points to the last interval with end <= End.
+ // r->end is the kill point.
+ return r->end >= Start && r->end < End;
}
// overlaps - Return true if the intersection of the two live intervals is
//
bool LiveInterval::overlapsFrom(const LiveInterval& other,
const_iterator StartPos) const {
+ assert(!empty() && "empty interval");
const_iterator i = begin();
const_iterator ie = end();
const_iterator j = StartPos;
/// overlaps - Return true if the live interval overlaps a range specified
/// by [Start, End).
-bool LiveInterval::overlaps(unsigned Start, unsigned End) const {
+bool LiveInterval::overlaps(SlotIndex Start, SlotIndex End) const {
assert(Start < End && "Invalid range");
- const_iterator I = begin();
- const_iterator E = end();
- const_iterator si = std::upper_bound(I, E, Start);
- const_iterator ei = std::upper_bound(I, E, End);
- if (si != ei)
- return true;
- if (si == I)
- return false;
- --si;
- return si->contains(Start);
+ const_iterator I = std::lower_bound(begin(), end(), End);
+ return I != begin() && (--I)->end > Start;
+}
+
+
+/// ValNo is dead, remove it. If it is the largest value number, just nuke it
+/// (and any other deleted values neighboring it), otherwise mark it as ~1U so
+/// it can be nuked later.
+void LiveInterval::markValNoForDeletion(VNInfo *ValNo) {
+ if (ValNo->id == getNumValNums()-1) {
+ do {
+ valnos.pop_back();
+ } while (!valnos.empty() && valnos.back()->isUnused());
+ } else {
+ ValNo->setIsUnused(true);
+ }
+}
+
+/// RenumberValues - Renumber all values in order of appearance and delete the
+/// remaining unused values.
+void LiveInterval::RenumberValues(LiveIntervals &lis) {
+ SmallPtrSet<VNInfo*, 8> Seen;
+ valnos.clear();
+ for (const_iterator I = begin(), E = end(); I != E; ++I) {
+ VNInfo *VNI = I->valno;
+ if (!Seen.insert(VNI))
+ continue;
+ assert(!VNI->isUnused() && "Unused valno used by live range");
+ VNI->id = (unsigned)valnos.size();
+ valnos.push_back(VNI);
+ }
}
/// extendIntervalEndTo - This method is used when we want to extend the range
/// specified by I to end at the specified endpoint. To do this, we should
/// merge and eliminate all ranges that this will overlap with. The iterator is
/// not invalidated.
-void LiveInterval::extendIntervalEndTo(Ranges::iterator I, unsigned NewEnd) {
+void LiveInterval::extendIntervalEndTo(Ranges::iterator I, SlotIndex NewEnd) {
assert(I != ranges.end() && "Not a valid interval!");
VNInfo *ValNo = I->valno;
- unsigned OldEnd = I->end;
// Search for the first interval that we can't merge with.
- Ranges::iterator MergeTo = next(I);
+ Ranges::iterator MergeTo = llvm::next(I);
for (; MergeTo != ranges.end() && NewEnd >= MergeTo->end; ++MergeTo) {
assert(MergeTo->valno == ValNo && "Cannot merge with differing values!");
}
I->end = std::max(NewEnd, prior(MergeTo)->end);
// Erase any dead ranges.
- ranges.erase(next(I), MergeTo);
-
- // Update kill info.
- removeKills(ValNo, OldEnd, I->end-1);
+ ranges.erase(llvm::next(I), MergeTo);
// If the newly formed range now touches the range after it and if they have
// the same value number, merge the two ranges into one range.
- Ranges::iterator Next = next(I);
+ Ranges::iterator Next = llvm::next(I);
if (Next != ranges.end() && Next->start <= I->end && Next->valno == ValNo) {
I->end = Next->end;
ranges.erase(Next);
/// specified by I to start at the specified endpoint. To do this, we should
/// merge and eliminate all ranges that this will overlap with.
LiveInterval::Ranges::iterator
-LiveInterval::extendIntervalStartTo(Ranges::iterator I, unsigned NewStart) {
+LiveInterval::extendIntervalStartTo(Ranges::iterator I, SlotIndex NewStart) {
assert(I != ranges.end() && "Not a valid interval!");
VNInfo *ValNo = I->valno;
MergeTo->end = I->end;
}
- ranges.erase(next(MergeTo), next(I));
+ ranges.erase(llvm::next(MergeTo), llvm::next(I));
return MergeTo;
}
LiveInterval::iterator
LiveInterval::addRangeFrom(LiveRange LR, iterator From) {
- unsigned Start = LR.start, End = LR.end;
+ SlotIndex Start = LR.start, End = LR.end;
iterator it = std::upper_bound(From, ranges.end(), Start);
// If the inserted interval starts in the middle or right at the end of
// endpoint as well.
if (End > it->end)
extendIntervalEndTo(it, End);
- else if (End < it->end)
- // Overlapping intervals, there might have been a kill here.
- removeKill(it->valno, End);
return it;
}
} else {
return ranges.insert(it, LR);
}
-/// isInOneLiveRange - Return true if the range specified is entirely in the
-/// a single LiveRange of the live interval.
-bool LiveInterval::isInOneLiveRange(unsigned Start, unsigned End) {
- Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start);
- if (I == ranges.begin())
- return false;
+/// extendInBlock - If this interval is live before Kill in the basic
+/// block that starts at StartIdx, extend it to be live up to Kill and return
+/// the value. If there is no live range before Kill, return NULL.
+VNInfo *LiveInterval::extendInBlock(SlotIndex StartIdx, SlotIndex Kill) {
+ if (empty())
+ return 0;
+ iterator I = std::upper_bound(begin(), end(), Kill.getPrevSlot());
+ if (I == begin())
+ return 0;
--I;
- return I->contains(Start) && I->contains(End-1);
+ if (I->end <= StartIdx)
+ return 0;
+ if (I->end < Kill)
+ extendIntervalEndTo(I, Kill);
+ return I->valno;
}
-
/// removeRange - Remove the specified range from this interval. Note that
/// the range must be in a single LiveRange in its entirety.
-void LiveInterval::removeRange(unsigned Start, unsigned End,
+void LiveInterval::removeRange(SlotIndex Start, SlotIndex End,
bool RemoveDeadValNo) {
// Find the LiveRange containing this span.
- Ranges::iterator I = std::upper_bound(ranges.begin(), ranges.end(), Start);
- assert(I != ranges.begin() && "Range is not in interval!");
- --I;
- assert(I->contains(Start) && I->contains(End-1) &&
- "Range is not entirely in interval!");
+ Ranges::iterator I = find(Start);
+ assert(I != ranges.end() && "Range is not in interval!");
+ assert(I->containsRange(Start, End) && "Range is not entirely in interval!");
// If the span we are removing is at the start of the LiveRange, adjust it.
VNInfo *ValNo = I->valno;
if (I->start == Start) {
if (I->end == End) {
- removeKills(I->valno, Start, End);
if (RemoveDeadValNo) {
// Check if val# is dead.
bool isDead = true;
if (II != I && II->valno == ValNo) {
isDead = false;
break;
- }
- if (isDead) {
- // Now that ValNo is dead, remove it. If it is the largest value
- // number, just nuke it (and any other deleted values neighboring it),
- // otherwise mark it as ~1U so it can be nuked later.
- if (ValNo->id == getNumValNums()-1) {
- do {
- VNInfo *VNI = valnos.back();
- valnos.pop_back();
- VNI->~VNInfo();
- } while (!valnos.empty() && valnos.back()->isUnused());
- } else {
- ValNo->setIsUnused(true);
}
+ if (isDead) {
+ // Now that ValNo is dead, remove it.
+ markValNoForDeletion(ValNo);
}
}
// Otherwise if the span we are removing is at the end of the LiveRange,
// adjust the other way.
if (I->end == End) {
- removeKills(ValNo, Start, End);
I->end = Start;
return;
}
// Otherwise, we are splitting the LiveRange into two pieces.
- unsigned OldEnd = I->end;
+ SlotIndex OldEnd = I->end;
I->end = Start; // Trim the old interval.
// Insert the new one.
- ranges.insert(next(I), LiveRange(End, OldEnd, ValNo));
+ ranges.insert(llvm::next(I), LiveRange(End, OldEnd, ValNo));
}
/// removeValNo - Remove all the ranges defined by the specified value#.
if (I->valno == ValNo)
ranges.erase(I);
} while (I != E);
- // Now that ValNo is dead, remove it. If it is the largest value
- // number, just nuke it (and any other deleted values neighboring it),
- // otherwise mark it as ~1U so it can be nuked later.
- if (ValNo->id == getNumValNums()-1) {
- do {
- VNInfo *VNI = valnos.back();
- valnos.pop_back();
- VNI->~VNInfo();
- } while (!valnos.empty() && valnos.back()->isUnused());
- } else {
- ValNo->setIsUnused(true);
- }
-}
-
-/// scaleNumbering - Renumber VNI and ranges to provide gaps for new
-/// instructions.
-void LiveInterval::scaleNumbering(unsigned factor) {
- // Scale ranges.
- for (iterator RI = begin(), RE = end(); RI != RE; ++RI) {
- RI->start = InstrSlots::scale(RI->start, factor);
- RI->end = InstrSlots::scale(RI->end, factor);
- }
-
- // Scale VNI info.
- for (vni_iterator VNI = vni_begin(), VNIE = vni_end(); VNI != VNIE; ++VNI) {
- VNInfo *vni = *VNI;
-
- if (vni->isDefAccurate())
- vni->def = InstrSlots::scale(vni->def, factor);
-
- for (unsigned i = 0; i < vni->kills.size(); ++i) {
- if (vni->kills[i] != 0)
- vni->kills[i] = InstrSlots::scale(vni->kills[i], factor);
- }
- }
+ // Now that ValNo is dead, remove it.
+ markValNoForDeletion(ValNo);
}
-/// getLiveRangeContaining - Return the live range that contains the
-/// specified index, or null if there is none.
-LiveInterval::const_iterator
-LiveInterval::FindLiveRangeContaining(unsigned Idx) const {
- const_iterator It = std::upper_bound(begin(), end(), Idx);
- if (It != ranges.begin()) {
- --It;
- if (It->contains(Idx))
- return It;
- }
-
- return end();
-}
-
-LiveInterval::iterator
-LiveInterval::FindLiveRangeContaining(unsigned Idx) {
- iterator It = std::upper_bound(begin(), end(), Idx);
- if (It != begin()) {
- --It;
- if (It->contains(Idx))
- return It;
+/// findDefinedVNInfo - Find the VNInfo defined by the specified
+/// index (register interval).
+VNInfo *LiveInterval::findDefinedVNInfoForRegInt(SlotIndex Idx) const {
+ for (LiveInterval::const_vni_iterator i = vni_begin(), e = vni_end();
+ i != e; ++i) {
+ if ((*i)->def == Idx)
+ return *i;
}
-
- return end();
-}
-/// findDefinedVNInfo - Find the VNInfo that's defined at the specified index
-/// (register interval) or defined by the specified register (stack inteval).
-VNInfo *LiveInterval::findDefinedVNInfo(unsigned DefIdxOrReg) const {
- VNInfo *VNI = NULL;
- for (LiveInterval::const_vni_iterator i = vni_begin(), e = vni_end();
- i != e; ++i)
- if ((*i)->def == DefIdxOrReg) {
- VNI = *i;
- break;
- }
- return VNI;
+ return 0;
}
/// join - Join two live intervals (this, and other) together. This applies
/// mappings to the value numbers in the LHS/RHS intervals as specified. If
/// the intervals are not joinable, this aborts.
-void LiveInterval::join(LiveInterval &Other, const int *LHSValNoAssignments,
- const int *RHSValNoAssignments,
+void LiveInterval::join(LiveInterval &Other,
+ const int *LHSValNoAssignments,
+ const int *RHSValNoAssignments,
SmallVector<VNInfo*, 16> &NewVNInfo,
MachineRegisterInfo *MRI) {
// Determine if any of our live range values are mapped. This is uncommon, so
- // we want to avoid the interval scan if not.
+ // we want to avoid the interval scan if not.
bool MustMapCurValNos = false;
unsigned NumVals = getNumValNums();
unsigned NumNewVals = NewVNInfo.size();
++OutIt;
for (iterator I = OutIt, E = end(); I != E; ++I) {
OutIt->valno = NewVNInfo[LHSValNoAssignments[I->valno->id]];
-
+
// If this live range has the same value # as its immediate predecessor,
// and if they are neighbors, remove one LiveRange. This happens when we
// have [0,3:0)[4,7:1) and map 0/1 onto the same value #.
OutIt->start = I->start;
OutIt->end = I->end;
}
-
+
// Didn't merge, on to the next one.
++OutIt;
}
}
-
+
// If we merge some live ranges, chop off the end.
ranges.erase(OutIt, end());
}
if (VNI) {
if (NumValNos >= NumVals)
valnos.push_back(VNI);
- else
+ else
valnos[NumValNos] = VNI;
VNI->id = NumValNos++; // Renumber val#.
}
InsertPos = addRangeFrom(*I, InsertPos);
}
- weight += Other.weight;
-
- // Update regalloc hint if currently there isn't one.
- if (TargetRegisterInfo::isVirtualRegister(reg) &&
- TargetRegisterInfo::isVirtualRegister(Other.reg)) {
- std::pair<unsigned, unsigned> Hint = MRI->getRegAllocationHint(reg);
- if (Hint.first == 0 && Hint.second == 0) {
- std::pair<unsigned, unsigned> OtherHint =
- MRI->getRegAllocationHint(Other.reg);
- if (OtherHint.first || OtherHint.second)
- MRI->setRegAllocationHint(reg, OtherHint.first, OtherHint.second);
- }
- }
+ ComputeJoinedWeight(Other);
}
/// MergeRangesInAsValue - Merge all of the intervals in RHS into this live
/// interval as the specified value number. The LiveRanges in RHS are
/// allowed to overlap with LiveRanges in the current interval, but only if
/// the overlapping LiveRanges have the specified value number.
-void LiveInterval::MergeRangesInAsValue(const LiveInterval &RHS,
+void LiveInterval::MergeRangesInAsValue(const LiveInterval &RHS,
VNInfo *LHSValNo) {
// TODO: Make this more efficient.
iterator InsertPos = begin();
/// The LiveRanges in RHS are allowed to overlap with LiveRanges in the
/// current interval, it will replace the value numbers of the overlaped
/// live ranges with the specified value number.
-void LiveInterval::MergeValueInAsValue(const LiveInterval &RHS,
- const VNInfo *RHSValNo, VNInfo *LHSValNo) {
- SmallVector<VNInfo*, 4> ReplacedValNos;
- iterator IP = begin();
+void LiveInterval::MergeValueInAsValue(
+ const LiveInterval &RHS,
+ const VNInfo *RHSValNo, VNInfo *LHSValNo) {
+ // TODO: Make this more efficient.
+ iterator InsertPos = begin();
for (const_iterator I = RHS.begin(), E = RHS.end(); I != E; ++I) {
if (I->valno != RHSValNo)
continue;
- unsigned Start = I->start, End = I->end;
- IP = std::upper_bound(IP, end(), Start);
- // If the start of this range overlaps with an existing liverange, trim it.
- if (IP != begin() && IP[-1].end > Start) {
- if (IP[-1].valno != LHSValNo) {
- ReplacedValNos.push_back(IP[-1].valno);
- IP[-1].valno = LHSValNo; // Update val#.
- }
- Start = IP[-1].end;
- // Trimmed away the whole range?
- if (Start >= End) continue;
- }
- // If the end of this range overlaps with an existing liverange, trim it.
- if (IP != end() && End > IP->start) {
- if (IP->valno != LHSValNo) {
- ReplacedValNos.push_back(IP->valno);
- IP->valno = LHSValNo; // Update val#.
- }
- End = IP->start;
- // If this trimmed away the whole range, ignore it.
- if (Start == End) continue;
- }
-
// Map the valno in the other live range to the current live range.
- IP = addRangeFrom(LiveRange(Start, End, LHSValNo), IP);
- }
-
-
- SmallSet<VNInfo*, 4> Seen;
- for (unsigned i = 0, e = ReplacedValNos.size(); i != e; ++i) {
- VNInfo *V1 = ReplacedValNos[i];
- if (Seen.insert(V1)) {
- bool isDead = true;
- for (const_iterator I = begin(), E = end(); I != E; ++I)
- if (I->valno == V1) {
- isDead = false;
- break;
- }
- if (isDead) {
- // Now that V1 is dead, remove it. If it is the largest value number,
- // just nuke it (and any other deleted values neighboring it), otherwise
- // mark it as ~1U so it can be nuked later.
- if (V1->id == getNumValNums()-1) {
- do {
- VNInfo *VNI = valnos.back();
- valnos.pop_back();
- VNI->~VNInfo();
- } while (!valnos.empty() && valnos.back()->isUnused());
- } else {
- V1->setIsUnused(true);
- }
- }
- }
- }
-}
-
-
-/// MergeInClobberRanges - For any live ranges that are not defined in the
-/// current interval, but are defined in the Clobbers interval, mark them
-/// used with an unknown definition value.
-void LiveInterval::MergeInClobberRanges(const LiveInterval &Clobbers,
- BumpPtrAllocator &VNInfoAllocator) {
- if (Clobbers.empty()) return;
-
- DenseMap<VNInfo*, VNInfo*> ValNoMaps;
- VNInfo *UnusedValNo = 0;
- iterator IP = begin();
- for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) {
- // For every val# in the Clobbers interval, create a new "unknown" val#.
- VNInfo *ClobberValNo = 0;
- DenseMap<VNInfo*, VNInfo*>::iterator VI = ValNoMaps.find(I->valno);
- if (VI != ValNoMaps.end())
- ClobberValNo = VI->second;
- else if (UnusedValNo)
- ClobberValNo = UnusedValNo;
- else {
- UnusedValNo = ClobberValNo = getNextValue(0, 0, false, VNInfoAllocator);
- ValNoMaps.insert(std::make_pair(I->valno, ClobberValNo));
- }
-
- bool Done = false;
- unsigned Start = I->start, End = I->end;
- // If a clobber range starts before an existing range and ends after
- // it, the clobber range will need to be split into multiple ranges.
- // Loop until the entire clobber range is handled.
- while (!Done) {
- Done = true;
- IP = std::upper_bound(IP, end(), Start);
- unsigned SubRangeStart = Start;
- unsigned SubRangeEnd = End;
-
- // If the start of this range overlaps with an existing liverange, trim it.
- if (IP != begin() && IP[-1].end > SubRangeStart) {
- SubRangeStart = IP[-1].end;
- // Trimmed away the whole range?
- if (SubRangeStart >= SubRangeEnd) continue;
- }
- // If the end of this range overlaps with an existing liverange, trim it.
- if (IP != end() && SubRangeEnd > IP->start) {
- // If the clobber live range extends beyond the existing live range,
- // it'll need at least another live range, so set the flag to keep
- // iterating.
- if (SubRangeEnd > IP->end) {
- Start = IP->end;
- Done = false;
- }
- SubRangeEnd = IP->start;
- // If this trimmed away the whole range, ignore it.
- if (SubRangeStart == SubRangeEnd) continue;
- }
-
- // Insert the clobber interval.
- IP = addRangeFrom(LiveRange(SubRangeStart, SubRangeEnd, ClobberValNo),
- IP);
- UnusedValNo = 0;
- }
- }
-
- if (UnusedValNo) {
- // Delete the last unused val#.
- valnos.pop_back();
- UnusedValNo->~VNInfo();
+ LiveRange Tmp = *I;
+ Tmp.valno = LHSValNo;
+ InsertPos = addRangeFrom(Tmp, InsertPos);
}
}
-void LiveInterval::MergeInClobberRange(unsigned Start, unsigned End,
- BumpPtrAllocator &VNInfoAllocator) {
- // Find a value # to use for the clobber ranges. If there is already a value#
- // for unknown values, use it.
- VNInfo *ClobberValNo = getNextValue(0, 0, false, VNInfoAllocator);
-
- iterator IP = begin();
- IP = std::upper_bound(IP, end(), Start);
-
- // If the start of this range overlaps with an existing liverange, trim it.
- if (IP != begin() && IP[-1].end > Start) {
- Start = IP[-1].end;
- // Trimmed away the whole range?
- if (Start >= End) return;
- }
- // If the end of this range overlaps with an existing liverange, trim it.
- if (IP != end() && End > IP->start) {
- End = IP->start;
- // If this trimmed away the whole range, ignore it.
- if (Start == End) return;
- }
-
- // Insert the clobber interval.
- addRangeFrom(LiveRange(Start, End, ClobberValNo), IP);
-}
/// MergeValueNumberInto - This method is called when two value nubmers
/// are found to be equivalent. This eliminates V1, replacing all
// Make sure V2 is smaller than V1.
if (V1->id < V2->id) {
- copyValNumInfo(V1, V2);
+ V1->copyFrom(*V2);
std::swap(V1, V2);
}
for (iterator I = begin(); I != end(); ) {
iterator LR = I++;
if (LR->valno != V1) continue; // Not a V1 LiveRange.
-
+
// Okay, we found a V1 live range. If it had a previous, touching, V2 live
// range, extend it.
if (LR != begin()) {
LR = Prev;
}
}
-
+
// Okay, now we have a V1 or V2 live range that is maximally merged forward.
// Ensure that it is a V2 live-range.
LR->valno = V2;
-
+
// If we can merge it into later V2 live ranges, do so now. We ignore any
// following V1 live ranges, as they will be merged in subsequent iterations
// of the loop.
}
}
}
-
- // Now that V1 is dead, remove it. If it is the largest value number, just
- // nuke it (and any other deleted values neighboring it), otherwise mark it as
- // ~1U so it can be nuked later.
- if (V1->id == getNumValNums()-1) {
- do {
- VNInfo *VNI = valnos.back();
- valnos.pop_back();
- VNI->~VNInfo();
- } while (valnos.back()->isUnused());
- } else {
- V1->setIsUnused(true);
- }
-
+
+ // Merge the relevant flags.
+ V2->mergeFlags(V1);
+
+ // Now that V1 is dead, remove it.
+ markValNoForDeletion(V1);
+
return V2;
}
void LiveInterval::Copy(const LiveInterval &RHS,
MachineRegisterInfo *MRI,
- BumpPtrAllocator &VNInfoAllocator) {
+ VNInfo::Allocator &VNInfoAllocator) {
ranges.clear();
valnos.clear();
std::pair<unsigned, unsigned> Hint = MRI->getRegAllocationHint(RHS.reg);
unsigned LiveInterval::getSize() const {
unsigned Sum = 0;
for (const_iterator I = begin(), E = end(); I != E; ++I)
- Sum += I->end - I->start;
+ Sum += I->start.distance(I->end);
return Sum;
}
-std::ostream& llvm::operator<<(std::ostream& os, const LiveRange &LR) {
+/// ComputeJoinedWeight - Set the weight of a live interval Joined
+/// after Other has been merged into it.
+void LiveInterval::ComputeJoinedWeight(const LiveInterval &Other) {
+ // If either of these intervals was spilled, the weight is the
+ // weight of the non-spilled interval. This can only happen with
+ // iterative coalescers.
+
+ if (Other.weight != HUGE_VALF) {
+ weight += Other.weight;
+ }
+ else if (weight == HUGE_VALF &&
+ !TargetRegisterInfo::isPhysicalRegister(reg)) {
+ // Remove this assert if you have an iterative coalescer
+ assert(0 && "Joining to spilled interval");
+ weight = Other.weight;
+ }
+ else {
+ // Otherwise the weight stays the same
+ // Remove this assert if you have an iterative coalescer
+ assert(0 && "Joining from spilled interval");
+ }
+}
+
+raw_ostream& llvm::operator<<(raw_ostream& os, const LiveRange &LR) {
return os << '[' << LR.start << ',' << LR.end << ':' << LR.valno->id << ")";
}
void LiveRange::dump() const {
- cerr << *this << "\n";
+ dbgs() << *this << "\n";
}
-void LiveInterval::print(std::ostream &OS,
- const TargetRegisterInfo *TRI) const {
- if (isStackSlot())
- OS << "SS#" << getStackSlotIndex();
- else if (TRI && TargetRegisterInfo::isPhysicalRegister(reg))
- OS << TRI->getName(reg);
- else
- OS << "%reg" << reg;
-
- OS << ',' << weight;
+void LiveInterval::print(raw_ostream &OS, const TargetRegisterInfo *TRI) const {
+ OS << PrintReg(reg, TRI);
+ if (weight != 0)
+ OS << ',' << weight;
if (empty())
OS << " EMPTY";
else {
OS << " = ";
for (LiveInterval::Ranges::const_iterator I = ranges.begin(),
- E = ranges.end(); I != E; ++I)
- OS << *I;
+ E = ranges.end(); I != E; ++I) {
+ OS << *I;
+ assert(I->valno == getValNumInfo(I->valno->id) && "Bad VNInfo");
+ }
}
-
+
// Print value number info.
if (getNumValNums()) {
OS << " ";
if (vni->isUnused()) {
OS << "x";
} else {
- if (!vni->isDefAccurate())
- OS << "?";
- else
- OS << vni->def;
- unsigned ee = vni->kills.size();
- if (ee || vni->hasPHIKill()) {
- OS << "-(";
- for (unsigned j = 0; j != ee; ++j) {
- OS << vni->kills[j];
- if (j != ee-1)
- OS << " ";
- }
- if (vni->hasPHIKill()) {
- if (ee)
- OS << " ";
- OS << "phi";
- }
- OS << ")";
- }
+ OS << vni->def;
+ if (vni->isPHIDef())
+ OS << "-phidef";
+ if (vni->hasPHIKill())
+ OS << "-phikill";
+ if (vni->hasRedefByEC())
+ OS << "-ec";
}
}
}
}
void LiveInterval::dump() const {
- cerr << *this << "\n";
+ dbgs() << *this << "\n";
}
-void LiveRange::print(std::ostream &os) const {
+void LiveRange::print(raw_ostream &os) const {
os << *this;
}
+
+unsigned ConnectedVNInfoEqClasses::Classify(const LiveInterval *LI) {
+ // Create initial equivalence classes.
+ EqClass.clear();
+ EqClass.grow(LI->getNumValNums());
+
+ const VNInfo *used = 0, *unused = 0;
+
+ // Determine connections.
+ for (LiveInterval::const_vni_iterator I = LI->vni_begin(), E = LI->vni_end();
+ I != E; ++I) {
+ const VNInfo *VNI = *I;
+ // Group all unused values into one class.
+ if (VNI->isUnused()) {
+ if (unused)
+ EqClass.join(unused->id, VNI->id);
+ unused = VNI;
+ continue;
+ }
+ used = VNI;
+ if (VNI->isPHIDef()) {
+ const MachineBasicBlock *MBB = LIS.getMBBFromIndex(VNI->def);
+ assert(MBB && "Phi-def has no defining MBB");
+ // Connect to values live out of predecessors.
+ for (MachineBasicBlock::const_pred_iterator PI = MBB->pred_begin(),
+ PE = MBB->pred_end(); PI != PE; ++PI)
+ if (const VNInfo *PVNI =
+ LI->getVNInfoAt(LIS.getMBBEndIdx(*PI).getPrevSlot()))
+ EqClass.join(VNI->id, PVNI->id);
+ } else {
+ // Normal value defined by an instruction. Check for two-addr redef.
+ // FIXME: This could be coincidental. Should we really check for a tied
+ // operand constraint?
+ // Note that VNI->def may be a use slot for an early clobber def.
+ if (const VNInfo *UVNI = LI->getVNInfoAt(VNI->def.getPrevSlot()))
+ EqClass.join(VNI->id, UVNI->id);
+ }
+ }
+
+ // Lump all the unused values in with the last used value.
+ if (used && unused)
+ EqClass.join(used->id, unused->id);
+
+ EqClass.compress();
+ return EqClass.getNumClasses();
+}
+
+void ConnectedVNInfoEqClasses::Distribute(LiveInterval *LIV[],
+ MachineRegisterInfo &MRI) {
+ assert(LIV[0] && "LIV[0] must be set");
+ LiveInterval &LI = *LIV[0];
+
+ // Rewrite instructions.
+ for (MachineRegisterInfo::reg_iterator RI = MRI.reg_begin(LI.reg),
+ RE = MRI.reg_end(); RI != RE;) {
+ MachineOperand &MO = RI.getOperand();
+ MachineInstr *MI = MO.getParent();
+ ++RI;
+ if (MO.isUse() && MO.isUndef())
+ continue;
+ // DBG_VALUE instructions should have been eliminated earlier.
+ SlotIndex Idx = LIS.getInstructionIndex(MI);
+ Idx = MO.isUse() ? Idx.getUseIndex() : Idx.getDefIndex();
+ const VNInfo *VNI = LI.getVNInfoAt(Idx);
+ assert(VNI && "Interval not live at use.");
+ MO.setReg(LIV[getEqClass(VNI)]->reg);
+ }
+
+ // Move runs to new intervals.
+ LiveInterval::iterator J = LI.begin(), E = LI.end();
+ while (J != E && EqClass[J->valno->id] == 0)
+ ++J;
+ for (LiveInterval::iterator I = J; I != E; ++I) {
+ if (unsigned eq = EqClass[I->valno->id]) {
+ assert((LIV[eq]->empty() || LIV[eq]->expiredAt(I->start)) &&
+ "New intervals should be empty");
+ LIV[eq]->ranges.push_back(*I);
+ } else
+ *J++ = *I;
+ }
+ LI.ranges.erase(J, E);
+
+ // Transfer VNInfos to their new owners and renumber them.
+ unsigned j = 0, e = LI.getNumValNums();
+ while (j != e && EqClass[j] == 0)
+ ++j;
+ for (unsigned i = j; i != e; ++i) {
+ VNInfo *VNI = LI.getValNumInfo(i);
+ if (unsigned eq = EqClass[i]) {
+ VNI->id = LIV[eq]->getNumValNums();
+ LIV[eq]->valnos.push_back(VNI);
+ } else {
+ VNI->id = j;
+ LI.valnos[j++] = VNI;
+ }
+ }
+ LI.valnos.resize(j);
+}
projects / oota-llvm.git / blobdiff