Remove use of reverse iterators in repairIntervalsInRange(). While they were
arguably better than forward iterators for this use case, they are confusing and
there are some implementation problems with reverse iterators and MI bundles.
llvm-svn: 175393
diff --git a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
index e09ac4b..0978d73 100644
--- a/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/llvm/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -1035,19 +1035,24 @@
void
LiveIntervals::repairIntervalsInRange(MachineBasicBlock *MBB,
- MachineBasicBlock::reverse_iterator RBegin,
- MachineBasicBlock::reverse_iterator REnd,
+ MachineBasicBlock::iterator Begin,
+ MachineBasicBlock::iterator End,
ArrayRef<unsigned> OrigRegs) {
+ SlotIndex startIdx;
+ if (Begin == MBB->begin())
+ startIdx = getMBBStartIdx(MBB);
+ else
+ startIdx = getInstructionIndex(prior(Begin)).getRegSlot();
+
for (unsigned i = 0, e = OrigRegs.size(); i != e; ++i) {
unsigned Reg = OrigRegs[i];
if (!TargetRegisterInfo::isVirtualRegister(Reg))
continue;
LiveInterval &LI = getInterval(Reg);
- SlotIndex startIdx = (REnd == MBB->rend()) ? getMBBStartIdx(MBB)
- : getInstructionIndex(&*REnd);
- for (MachineBasicBlock::reverse_iterator I = RBegin; I != REnd; ++I) {
- MachineInstr *MI = &*I;
+ for (MachineBasicBlock::iterator I = End; I != Begin;) {
+ --I;
+ MachineInstr *MI = I;
SlotIndex instrIdx = getInstructionIndex(MI);
for (MachineInstr::mop_iterator OI = MI->operands_begin(),
@@ -1059,7 +1064,7 @@
assert(MO.isUse() && "Register defs are not yet supported.");
if (!LI.liveAt(instrIdx)) {
- LiveRange *LR = LI.getLiveRangeContaining(startIdx.getRegSlot());
+ LiveRange *LR = LI.getLiveRangeContaining(startIdx);
assert(LR && "Used registers must be live-in.");
LR->end = instrIdx.getRegSlot();
break;