Create a new LiveRangeEdit class to keep track of the new registers created when

splitting or spillling, and to help with rematerialization.

Use LiveRangeEdit in InlineSpiller and SplitKit. This will eventually make it
possible to share remat code between InlineSpiller and SplitKit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116543 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 21 insertions, 32 deletions

diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 2ab7fa83e5..ea551bb623 100644
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -14,6 +14,7 @@
 
 #define DEBUG_TYPE "splitter"
 #include "SplitKit.h"
+#include "LiveRangeEdit.h"
 #include "VirtRegMap.h"
 #include "llvm/CodeGen/CalcSpillWeights.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
@@ -580,15 +581,14 @@ VNInfo *LiveIntervalMap::defByCopyFrom(unsigned Reg,
 
 /// Create a new SplitEditor for editing the LiveInterval analyzed by SA.
 SplitEditor::SplitEditor(SplitAnalysis &sa, LiveIntervals &lis, VirtRegMap &vrm,
-                         SmallVectorImpl<LiveInterval*> &intervals)
+                         LiveRangeEdit &edit)
   : sa_(sa), lis_(lis), vrm_(vrm),
     mri_(vrm.getMachineFunction().getRegInfo()),
     tii_(*vrm.getMachineFunction().getTarget().getInstrInfo()),
+    edit_(edit),
     curli_(sa_.getCurLI()),
     dupli_(lis_, *curli_),
-    openli_(lis_, *curli_),
-    intervals_(intervals),
-    firstInterval(intervals_.size())
+    openli_(lis_, *curli_)
 {
   assert(curli_ && "SplitEditor created from empty SplitAnalysis");
 
@@ -599,17 +599,9 @@ SplitEditor::SplitEditor(SplitAnalysis &sa, LiveIntervals &lis, VirtRegMap &vrm,
 
 }
 
-LiveInterval *SplitEditor::createInterval() {
-  unsigned Reg = mri_.createVirtualRegister(mri_.getRegClass(curli_->reg));
-  LiveInterval &Intv = lis_.getOrCreateInterval(Reg);
-  vrm_.grow();
-  vrm_.assignVirt2StackSlot(Reg, vrm_.getStackSlot(curli_->reg));
-  return &Intv;
-}
-
 bool SplitEditor::intervalsLiveAt(SlotIndex Idx) const {
-  for (int i = firstInterval, e = intervals_.size(); i != e; ++i)
-    if (intervals_[i]->liveAt(Idx))
+  for (LiveRangeEdit::iterator I = edit_.begin(), E = edit_.end(); I != E; ++I)
+    if (*I != dupli_.getLI() && (*I)->liveAt(Idx))
       return true;
   return false;
 }
@@ -619,10 +611,9 @@ void SplitEditor::openIntv() {
   assert(!openli_.getLI() && "Previous LI not closed before openIntv");
 
   if (!dupli_.getLI())
-    dupli_.reset(createInterval());
+    dupli_.reset(&edit_.create(mri_, lis_, vrm_));
 
-  openli_.reset(createInterval());
-  intervals_.push_back(openli_.getLI());
+  openli_.reset(&edit_.create(mri_, lis_, vrm_));
 }
 
 /// enterIntvBefore - Enter openli before the instruction at Idx. If curli is
@@ -749,8 +740,9 @@ void SplitEditor::rewrite(unsigned reg) {
     SlotIndex Idx = lis_.getInstructionIndex(MI);
     Idx = MO.isUse() ? Idx.getUseIndex() : Idx.getDefIndex();
     LiveInterval *LI = 0;
-    for (unsigned i = firstInterval, e = intervals_.size(); i != e; ++i) {
-      LiveInterval *testli = intervals_[i];
+    for (LiveRangeEdit::iterator I = edit_.begin(), E = edit_.end(); I != E;
+         ++I) {
+      LiveInterval *testli = *I;
       if (testli->liveAt(Idx)) {
         LI = testli;
         break;
@@ -769,9 +761,10 @@ SplitEditor::addTruncSimpleRange(SlotIndex Start, SlotIndex End, VNInfo *VNI) {
   typedef std::pair<LiveInterval::const_iterator,
                     LiveInterval::const_iterator> IIPair;
   SmallVector<IIPair, 8> Iters;
-  for (int i = firstInterval, e = intervals_.size(); i != e; ++i) {
-    LiveInterval::const_iterator I = intervals_[i]->find(Start);
-    LiveInterval::const_iterator E = intervals_[i]->end();
+  for (LiveRangeEdit::iterator LI = edit_.begin(), LE = edit_.end(); LI != LE;
+       ++LI) {
+    LiveInterval::const_iterator I = (*LI)->find(Start);
+    LiveInterval::const_iterator E = (*LI)->end();
     if (I != E)
       Iters.push_back(std::make_pair(I, E));
   }
@@ -868,20 +861,16 @@ void SplitEditor::finish() {
   if (unsigned NumComp = ConEQ.Classify(dupli_.getLI())) {
     DEBUG(dbgs() << "  Remainder has " << NumComp << " connected components: "
                  << *dupli_.getLI() << '\n');
-    unsigned firstComp = intervals_.size();
-    intervals_.push_back(dupli_.getLI());
     // Did the remainder break up? Create intervals for all the components.
     if (NumComp > 1) {
+      SmallVector<LiveInterval*, 8> dups;
+      dups.push_back(dupli_.getLI());
       for (unsigned i = 1; i != NumComp; ++i)
-        intervals_.push_back(createInterval());
-      ConEQ.Distribute(&intervals_[firstComp]);
+        dups.push_back(&edit_.create(mri_, lis_, vrm_));
+      ConEQ.Distribute(&dups[0]);
       // Rewrite uses to the new regs.
       rewrite(dupli_.getLI()->reg);
     }
-  } else {
-    DEBUG(dbgs() << "  dupli became empty?\n");
-    lis_.removeInterval(dupli_.getLI()->reg);
-    dupli_.reset(0);
   }
 
   // Rewrite instructions.
@@ -889,8 +878,8 @@ void SplitEditor::finish() {
 
   // Calculate spill weight and allocation hints for new intervals.
   VirtRegAuxInfo vrai(vrm_.getMachineFunction(), lis_, sa_.loops_);
-  for (unsigned i = firstInterval, e = intervals_.size(); i != e; ++i) {
-    LiveInterval &li = *intervals_[i];
+  for (LiveRangeEdit::iterator I = edit_.begin(), E = edit_.end(); I != E; ++I){
+    LiveInterval &li = **I;
     vrai.CalculateRegClass(li.reg);
     vrai.CalculateWeightAndHint(li);
     DEBUG(dbgs() << "  new interval " << mri_.getRegClass(li.reg)->getName()