CodeGen: MachineInstr::getIterator() => getInstrIterator(), NFC

Delete MachineInstr::getIterator(), since the term "iterator" is
overloaded when talking about MachineInstr.

- Downcast to ilist_node in iplist::getNextNode() and getPrevNode() so
  that ilist_node::getIterator() is still available.
- Add it back as MachineInstr::getInstrIterator().  This matches the
  naming in MachineBasicBlock.
- Add MachineInstr::getBundleIterator().  This is explicitly called
  "bundle" (not matching MachineBasicBlock) to disintinguish it clearly
  from ilist_node::getIterator().
- Update all calls.  Some of these I switched to `auto` to remove
  boiler-plate, since the new name is clear about the type.

There was one call I updated that looked fishy, but it wasn't clear what
the right answer was.  This was in X86FrameLowering::inlineStackProbe(),
added in r252578 in lib/Target/X86/X86FrameLowering.cpp.  I opted to
leave the behaviour unchanged, but I'll reply to the original commit on
the list in a moment.

llvm-svn: 261504

1 files changed, 10 insertions, 14 deletions

diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp
index 4103253133e..86dbf7a3070 100644
--- a/llvm/lib/CodeGen/MachineInstr.cpp
+++ b/llvm/lib/CodeGen/MachineInstr.cpp
@@ -934,7 +934,7 @@ MachineInstr::mergeMemRefsWith(const MachineInstr& Other) {
 
 bool MachineInstr::hasPropertyInBundle(unsigned Mask, QueryType Type) const {
   assert(!isBundledWithPred() && "Must be called on bundle header");
-  for (MachineBasicBlock::const_instr_iterator MII = getIterator();; ++MII) {
+  for (auto MII = getInstrIterator();; ++MII) {
     if (MII->getDesc().getFlags() & Mask) {
       if (Type == AnyInBundle)
         return true;
@@ -958,10 +958,10 @@ bool MachineInstr::isIdenticalTo(const MachineInstr *Other,
 
   if (isBundle()) {
     // Both instructions are bundles, compare MIs inside the bundle.
-    MachineBasicBlock::const_instr_iterator I1 = getIterator();
-    MachineBasicBlock::const_instr_iterator E1 = getParent()->instr_end();
-    MachineBasicBlock::const_instr_iterator I2 = Other->getIterator();
-    MachineBasicBlock::const_instr_iterator E2= Other->getParent()->instr_end();
+    auto I1 = getInstrIterator();
+    auto E1 = getParent()->instr_end();
+    auto I2 = Other->getInstrIterator();
+    auto E2 = Other->getParent()->instr_end();
     while (++I1 != E1 && I1->isInsideBundle()) {
       ++I2;
       if (I2 == E2 || !I2->isInsideBundle() || !I1->isIdenticalTo(&*I2, Check))
@@ -1069,8 +1069,7 @@ unsigned MachineInstr::getNumExplicitOperands() const {
 void MachineInstr::bundleWithPred() {
   assert(!isBundledWithPred() && "MI is already bundled with its predecessor");
   setFlag(BundledPred);
-  MachineBasicBlock::instr_iterator Pred = getIterator();
-  --Pred;
+  auto Pred = --getInstrIterator();
   assert(!Pred->isBundledWithSucc() && "Inconsistent bundle flags");
   Pred->setFlag(BundledSucc);
 }
@@ -1078,8 +1077,7 @@ void MachineInstr::bundleWithPred() {
 void MachineInstr::bundleWithSucc() {
   assert(!isBundledWithSucc() && "MI is already bundled with its successor");
   setFlag(BundledSucc);
-  MachineBasicBlock::instr_iterator Succ = getIterator();
-  ++Succ;
+  auto Succ = ++getInstrIterator();
   assert(!Succ->isBundledWithPred() && "Inconsistent bundle flags");
   Succ->setFlag(BundledPred);
 }
@@ -1087,8 +1085,7 @@ void MachineInstr::bundleWithSucc() {
 void MachineInstr::unbundleFromPred() {
   assert(isBundledWithPred() && "MI isn't bundled with its predecessor");
   clearFlag(BundledPred);
-  MachineBasicBlock::instr_iterator Pred = getIterator();
-  --Pred;
+  auto Pred = --getInstrIterator();
   assert(Pred->isBundledWithSucc() && "Inconsistent bundle flags");
   Pred->clearFlag(BundledSucc);
 }
@@ -1096,8 +1093,7 @@ void MachineInstr::unbundleFromPred() {
 void MachineInstr::unbundleFromSucc() {
   assert(isBundledWithSucc() && "MI isn't bundled with its successor");
   clearFlag(BundledSucc);
-  MachineBasicBlock::instr_iterator Succ = getIterator();
-  ++Succ;
+  auto Succ = ++getInstrIterator();
   assert(Succ->isBundledWithPred() && "Inconsistent bundle flags");
   Succ->clearFlag(BundledPred);
 }
@@ -1232,7 +1228,7 @@ const TargetRegisterClass *MachineInstr::getRegClassConstraintEffect(
 /// Return the number of instructions inside the MI bundle, not counting the
 /// header instruction.
 unsigned MachineInstr::getBundleSize() const {
-  MachineBasicBlock::const_instr_iterator I = getIterator();
+  auto I = getInstrIterator();
   unsigned Size = 0;
   while (I->isBundledWithSucc()) {
     ++Size;