CodeGen: Use MachineInstr& in SlotIndexes.cpp, NFC

Avoid implicit conversions from iterator to pointer by preferring
MachineInstr& and using range-based for loops.

llvm-svn: 274354

1 files changed, 13 insertions, 18 deletions

diff --git a/llvm/lib/CodeGen/SlotIndexes.cpp b/llvm/lib/CodeGen/SlotIndexes.cpp
index f0713ef..dba103e 100644
--- a/llvm/lib/CodeGen/SlotIndexes.cpp
+++ b/llvm/lib/CodeGen/SlotIndexes.cpp
@@ -69,34 +69,29 @@ bool SlotIndexes::runOnMachineFunction(MachineFunction &fn) {
   indexList.push_back(createEntry(nullptr, index));
 
   // Iterate over the function.
-  for (MachineFunction::iterator mbbItr = mf->begin(), mbbEnd = mf->end();
-       mbbItr != mbbEnd; ++mbbItr) {
-    MachineBasicBlock *mbb = &*mbbItr;
-
+  for (MachineBasicBlock &MBB : *mf) {
     // Insert an index for the MBB start.
     SlotIndex blockStartIndex(&indexList.back(), SlotIndex::Slot_Block);
 
-    for (MachineBasicBlock::iterator miItr = mbb->begin(), miEnd = mbb->end();
-         miItr != miEnd; ++miItr) {
-      MachineInstr *mi = miItr;
-      if (mi->isDebugValue())
+    for (MachineInstr &MI : MBB) {
+      if (MI.isDebugValue())
         continue;
 
       // Insert a store index for the instr.
-      indexList.push_back(createEntry(mi, index += SlotIndex::InstrDist));
+      indexList.push_back(createEntry(&MI, index += SlotIndex::InstrDist));
 
       // Save this base index in the maps.
-      mi2iMap.insert(std::make_pair(mi, SlotIndex(&indexList.back(),
-                                                  SlotIndex::Slot_Block)));
+      mi2iMap.insert(std::make_pair(
+          &MI, SlotIndex(&indexList.back(), SlotIndex::Slot_Block)));
     }
 
     // We insert one blank instructions between basic blocks.
     indexList.push_back(createEntry(nullptr, index += SlotIndex::InstrDist));
 
-    MBBRanges[mbb->getNumber()].first = blockStartIndex;
-    MBBRanges[mbb->getNumber()].second = SlotIndex(&indexList.back(),
+    MBBRanges[MBB.getNumber()].first = blockStartIndex;
+    MBBRanges[MBB.getNumber()].second = SlotIndex(&indexList.back(),
                                                    SlotIndex::Slot_Block);
-    idx2MBBMap.push_back(IdxMBBPair(blockStartIndex, mbb));
+    idx2MBBMap.push_back(IdxMBBPair(blockStartIndex, &MBB));
   }
 
   // Sort the Idx2MBBMap
@@ -182,7 +177,7 @@ void SlotIndexes::repairIndexesInRange(MachineBasicBlock *MBB,
            "Decremented past the beginning of region to repair.");
 
     MachineInstr *SlotMI = ListI->getInstr();
-    MachineInstr *MI = (MBBI != MBB->end() && !pastStart) ? MBBI : nullptr;
+    MachineInstr *MI = (MBBI != MBB->end() && !pastStart) ? &*MBBI : nullptr;
     bool MBBIAtBegin = MBBI == Begin && (!includeStart || pastStart);
 
     if (SlotMI == MI && !MBBIAtBegin) {
@@ -207,9 +202,9 @@ void SlotIndexes::repairIndexesInRange(MachineBasicBlock *MBB,
   // to update the IndexList while we are iterating it.
   for (MachineBasicBlock::iterator I = End; I != Begin;) {
     --I;
-    MachineInstr *MI = I;
-    if (!MI->isDebugValue() && mi2iMap.find(MI) == mi2iMap.end())
-      insertMachineInstrInMaps(*MI);
+    MachineInstr &MI = *I;
+    if (!MI.isDebugValue() && mi2iMap.find(&MI) == mi2iMap.end())
+      insertMachineInstrInMaps(MI);
   }
 }