Discard split intervals made empty due to folding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44565 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index 2d34a17..7a97624 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -1234,6 +1234,7 @@
for (unsigned i = 0, e = spills.size(); i != e; ++i) {
int index = spills[i].index;
unsigned VReg = spills[i].vreg;
+ LiveInterval &nI = getOrCreateInterval(VReg);
bool isReMat = vrm.isReMaterialized(VReg);
MachineInstr *MI = getInstructionFromIndex(index);
bool CanFold = false;
@@ -1269,6 +1270,7 @@
if (FoundUse > 0)
// Also folded uses, do not issue a load.
eraseRestoreInfo(Id, index, VReg, RestoreMBBs, RestoreIdxes);
+ nI.removeRange(getDefIndex(index), getStoreIndex(index));
}
}
@@ -1288,6 +1290,7 @@
if (index == -1)
continue;
unsigned VReg = restores[i].vreg;
+ LiveInterval &nI = getOrCreateInterval(VReg);
MachineInstr *MI = getInstructionFromIndex(index);
bool CanFold = false;
Ops.clear();
@@ -1326,15 +1329,23 @@
}
// If folding is not possible / failed, then tell the spiller to issue a
// load / rematerialization for us.
- if (!Folded)
+ if (Folded)
+ nI.removeRange(getLoadIndex(index), getUseIndex(index)+1);
+ else
vrm.addRestorePoint(VReg, MI);
}
Id = RestoreMBBs.find_next(Id);
}
- // Finalize spill weights.
- for (unsigned i = 0, e = NewLIs.size(); i != e; ++i)
- NewLIs[i]->weight /= NewLIs[i]->getSize();
+ // Finalize spill weights and filter out dead intervals.
+ std::vector<LiveInterval*> RetNewLIs;
+ for (unsigned i = 0, e = NewLIs.size(); i != e; ++i) {
+ LiveInterval *LI = NewLIs[i];
+ if (!LI->empty()) {
+ LI->weight /= LI->getSize();
+ RetNewLIs.push_back(LI);
+ }
+ }
- return NewLIs;
+ return RetNewLIs;
}