Pull the LiveRange and LiveInterval classes out of LiveIntervals.h (which

will soon be renamed) into their own file.  The new file should not emit
DEBUG output or have other side effects.  The LiveInterval class also now
doesn't know whether its working on registers or some other thing.

In the future we will want to use the LiveInterval class and friends to do
stack packing.  In addition to a code simplification, this will allow us to
do it more easily.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15134 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 25 insertions, 164 deletions

diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index d59c114808..0d6ea11ff4 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -250,6 +250,7 @@ std::vector<LiveInterval*> LiveIntervals::addIntervalsForSpills(
                         // the spill weight is now infinity as it
                         // cannot be spilled again
                         nI.weight = HUGE_VAL;
+                        DEBUG(std::cerr << " +" << LiveRange(start, end));
                         nI.addRange(LiveRange(start, end));
                         added.push_back(&nI);
                         // update live variables
@@ -309,7 +310,7 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock* mbb,
               assert(vi.AliveBlocks.empty() && 
                      "Shouldn't be alive across any blocks!");
               interval.addRange(LiveRange(defIndex, killIdx));
-              DEBUG(std::cerr << "\n");
+              DEBUG(std::cerr << " +" << LiveRange(defIndex, killIdx) << "\n");
               return;
            }
        }
@@ -318,9 +319,10 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock* mbb,
        // of the defining block, potentially live across some blocks, then is
        // live into some number of blocks, but gets killed.  Start by adding a
        // range that goes from this definition to the end of the defining block.
-       interval.addRange(LiveRange(defIndex, 
-                                   getInstructionIndex(&mbb->back()) +
-                                         InstrSlots::NUM));
+       LiveRange NewLR(defIndex, getInstructionIndex(&mbb->back()) +
+                                                   InstrSlots::NUM);
+       DEBUG(std::cerr << " +" << NewLR);
+       interval.addRange(NewLR);
 
        // Iterate over all of the blocks that the variable is completely
        // live in, adding [insrtIndex(begin), instrIndex(end)+4) to the
@@ -329,9 +331,10 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock* mbb,
            if (vi.AliveBlocks[i]) {
                MachineBasicBlock* mbb = mf_->getBlockNumbered(i);
                if (!mbb->empty()) {
-                   interval.addRange(LiveRange(
-                       getInstructionIndex(&mbb->front()),
-                       getInstructionIndex(&mbb->back()) + InstrSlots::NUM));
+                 LiveRange LR(getInstructionIndex(&mbb->front()),
+                             getInstructionIndex(&mbb->back())+InstrSlots::NUM);
+                 interval.addRange(LR);
+                 DEBUG(std::cerr << " +" << LR);
                }
            }
        }
@@ -340,9 +343,10 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock* mbb,
        // block to the 'use' slot of the killing instruction.
        for (unsigned i = 0, e = vi.Kills.size(); i != e; ++i) {
            MachineInstr *Kill = vi.Kills[i];
-           interval.addRange(LiveRange(
-                             getInstructionIndex(Kill->getParent()->begin()),
-                             getUseIndex(getInstructionIndex(Kill))+1));
+           LiveRange LR(getInstructionIndex(Kill->getParent()->begin()),
+                        getUseIndex(getInstructionIndex(Kill))+1);
+           interval.addRange(LR);
+           DEBUG(std::cerr << " +" << LR);
        }
 
     } else {
@@ -359,8 +363,10 @@ void LiveIntervals::handleVirtualRegisterDef(MachineBasicBlock* mbb,
          // the defined value will be live until the end of the basic block it
          // is defined in.
          unsigned defIndex = getDefIndex(getInstructionIndex(mi));
-         interval.addRange(LiveRange(defIndex, 
-                           getInstructionIndex(&mbb->back()) +InstrSlots::NUM));
+         LiveRange LR(defIndex, 
+                      getInstructionIndex(&mbb->back()) +InstrSlots::NUM);
+         interval.addRange(LR);
+         DEBUG(std::cerr << " +" << LR);
        }
        interval.isDefinedOnce = false;
     }
@@ -413,7 +419,7 @@ void LiveIntervals::handlePhysicalRegisterDef(MachineBasicBlock* mbb,
 exit:
     assert(start < end && "did not find end of interval?");
     interval.addRange(LiveRange(start, end));
-    DEBUG(std::cerr << '\n');
+    DEBUG(std::cerr << " +" << LiveRange(start, end) << '\n');
 }
 
 void LiveIntervals::handleRegisterDef(MachineBasicBlock* mbb,
@@ -547,10 +553,11 @@ void LiveIntervals::joinIntervalsInMachineBB(MachineBasicBlock *MBB) {
                     continue;
                 }
 
-                // if their intervals do not overlap we join them
-                if ((intA->isDefinedOnce && intB->isDefinedOnce) ||
+                // if their intervals do not overlap we join them.
+                if ((intA->containsOneValue() && intB->containsOneValue()) ||
                     !intB->overlaps(*intA)) {
                     intA->join(*intB);
+                    ++numJoins;
                     DEBUG(std::cerr << "Joined.  Result = " << *intA << "\n");
                     r2iB->second = r2iA->second;
                     r2rMap_.insert(std::make_pair(intB->reg, intA->reg));
@@ -582,6 +589,7 @@ void LiveIntervals::joinIntervalsInMachineBB(MachineBasicBlock *MBB) {
                 if (!intA->overlaps(*intB) &&
                     !overlapsAliases(*intA, *intB)) {
                     intA->join(*intB);
+                    ++numJoins;
                     DEBUG(std::cerr << "Joined.  Result = " << *intA << "\n");
                     r2iB->second = r2iA->second;
                     r2rMap_.insert(std::make_pair(intB->reg, intA->reg));
@@ -656,158 +664,11 @@ LiveInterval& LiveIntervals::getOrCreateInterval(unsigned reg)
 {
     Reg2IntervalMap::iterator r2iit = r2iMap_.lower_bound(reg);
     if (r2iit == r2iMap_.end() || r2iit->first != reg) {
-        intervals_.push_back(LiveInterval(reg));
+        float Weight = MRegisterInfo::isPhysicalRegister(reg) ?  HUGE_VAL :0.0F;
+        intervals_.push_back(LiveInterval(reg, Weight));
         r2iit = r2iMap_.insert(r2iit, std::make_pair(reg, --intervals_.end()));
     }
 
     return *r2iit->second;
 }
 
-LiveInterval::LiveInterval(unsigned r)
-    : reg(r),
-      weight((MRegisterInfo::isPhysicalRegister(r) ?  HUGE_VAL : 0.0F)),
-      isDefinedOnce(false) {
-}
-
-bool LiveInterval::spilled() const
-{
-    return (weight == HUGE_VAL &&
-            MRegisterInfo::isVirtualRegister(reg));
-}
-
-// 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 index) const
-{
-    LiveRange dummy(index, index+1);
-    Ranges::const_iterator r = std::upper_bound(ranges.begin(),
-                                                ranges.end(),
-                                                dummy);
-    if (r == ranges.begin())
-        return false;
-
-    --r;
-    return index >= r->start && index < r->end;
-}
-
-// An example for overlaps():
-//
-// 0: A = ...
-// 4: B = ...
-// 8: C = A + B ;; last use of A
-//
-// The live intervals should look like:
-//
-// A = [3, 11)
-// B = [7, x)
-// C = [11, y)
-//
-// A->overlaps(C) should return false since we want to be able to join
-// A and C.
-bool LiveInterval::overlaps(const LiveInterval& other) const
-{
-    Ranges::const_iterator i = ranges.begin();
-    Ranges::const_iterator ie = ranges.end();
-    Ranges::const_iterator j = other.ranges.begin();
-    Ranges::const_iterator je = other.ranges.end();
-    if (i->start < j->start) {
-        i = std::upper_bound(i, ie, *j);
-        if (i != ranges.begin()) --i;
-    }
-    else if (j->start < i->start) {
-        j = std::upper_bound(j, je, *i);
-        if (j != other.ranges.begin()) --j;
-    }
-
-    while (i != ie && j != je) {
-        if (i->start == j->start)
-            return true;
-
-        if (i->start > j->start) {
-            swap(i, j);
-            swap(ie, je);
-        }
-        assert(i->start < j->start);
-
-        if (i->end > j->start)
-            return true;
-        ++i;
-    }
-
-    return false;
-}
-
-void LiveInterval::addRange(LiveRange LR) {
-    DEBUG(std::cerr << " +" << LR);
-    Ranges::iterator it =
-        ranges.insert(std::upper_bound(ranges.begin(), ranges.end(), LR), LR);
-
-    mergeRangesBackward(mergeRangesForward(it));
-}
-
-void LiveInterval::join(const LiveInterval& other)
-{
-    Ranges::iterator cur = ranges.begin();
-    isDefinedOnce &= other.isDefinedOnce;
-
-    for (Ranges::const_iterator i = other.ranges.begin(),
-             e = other.ranges.end(); i != e; ++i) {
-        cur = ranges.insert(std::upper_bound(cur, ranges.end(), *i), *i);
-        cur = mergeRangesForward(cur);
-        cur = mergeRangesBackward(cur);
-    }
-    weight += other.weight;
-    ++numJoins;
-}
-
-LiveInterval::Ranges::iterator LiveInterval::
-mergeRangesForward(Ranges::iterator it)
-{
-    Ranges::iterator n;
-    while ((n = next(it)) != ranges.end()) {
-        if (n->start > it->end)
-            break;
-        it->end = std::max(it->end, n->end);
-        n = ranges.erase(n);
-    }
-    return it;
-}
-
-LiveInterval::Ranges::iterator LiveInterval::
-mergeRangesBackward(Ranges::iterator it)
-{
-    while (it != ranges.begin()) {
-        Ranges::iterator p = prior(it);
-        if (it->start > p->end)
-            break;
-
-        it->start = std::min(it->start, p->start);
-        it->end = std::max(it->end, p->end);
-        it = ranges.erase(p);
-    }
-
-    return it;
-}
-
-std::ostream& llvm::operator<<(std::ostream& os, const LiveRange &LR) {
-  return os << "[" << LR.start << "," << LR.end << ")";
-}
-
-
-std::ostream& llvm::operator<<(std::ostream& os, const LiveInterval& li)
-{
-    os << "%reg" << li.reg << ',' << li.weight;
-    if (li.empty())
-        return os << "EMPTY";
-
-    os << " = ";
-    for (LiveInterval::Ranges::const_iterator i = li.ranges.begin(),
-           e = li.ranges.end(); i != e; ++i)
-        os << *i;
-    return os;
-}