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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@175393 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Cameron Zwarich 2013-02-17 11:09:00 +00:00
parent 7324d4e593
commit 680c98f632
3 changed files with 18 additions and 21 deletions

View File

@ -282,9 +282,9 @@ namespace llvm {
bool UpdateFlags = false);
/// repairIntervalsInRange - Update live intervals for instructions in a
/// small range of reverse iterators. It is intended for use after target
/// hooks that may insert or remove instructions, and is only efficient for
/// a small number of instructions.
/// range of iterators. It is intended for use after target hooks that may
/// insert or remove instructions, and is only efficient for a small number
/// of instructions.
///
/// OrigRegs is a vector of registers that were originally used by the
/// instructions in the range between the two iterators.
@ -292,8 +292,8 @@ namespace llvm {
/// Currently, the only only changes that are supported are simple removal
/// and addition of uses.
void repairIntervalsInRange(MachineBasicBlock *MBB,
MachineBasicBlock::reverse_iterator RBegin,
MachineBasicBlock::reverse_iterator REnd,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
ArrayRef<unsigned> OrigRegs);
// Register mask functions.

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@ -1035,19 +1035,24 @@ void LiveIntervals::handleMoveIntoBundle(MachineInstr* MI,
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 @@ LiveIntervals::repairIntervalsInRange(MachineBasicBlock *MBB,
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;

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@ -851,15 +851,7 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
// Update all intervals for registers whose uses may have been modified by
// updateTerminator().
iterator FirstTerminator = getFirstTerminator();
reverse_iterator PreTerminators;
if (FirstTerminator == begin())
PreTerminators = rend();
else if (FirstTerminator == end())
PreTerminators = rbegin();
else
PreTerminators = reverse_iterator(FirstTerminator);
LIS->repairIntervalsInRange(this, rbegin(), PreTerminators, UsedRegs);
LIS->repairIntervalsInRange(this, getFirstTerminator(), end(), UsedRegs);
}
if (MachineDominatorTree *MDT =