From 6c5badba143ad8bb581bd787b5b6e1844aaa65da Mon Sep 17 00:00:00 2001
From: Sanjay Patel <spatel@rotateright.com>
Date: Wed, 6 Jan 2016 00:45:42 +0000
Subject: [PATCH] rangify; NFCI

llvm-svn: 256891
---
 lib/CodeGen/MachineCSE.cpp | 38 ++++++++++++++------------------------
 1 file changed, 14 insertions(+), 24 deletions(-)

diff --git a/lib/CodeGen/MachineCSE.cpp b/lib/CodeGen/MachineCSE.cpp
index 021707b7c3c..aad376c4702 100644
--- a/lib/CodeGen/MachineCSE.cpp
+++ b/lib/CodeGen/MachineCSE.cpp
@@ -122,8 +122,7 @@ INITIALIZE_PASS_END(MachineCSE, "machine-cse",
 bool MachineCSE::PerformTrivialCopyPropagation(MachineInstr *MI,
                                                MachineBasicBlock *MBB) {
   bool Changed = false;
-  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-    MachineOperand &MO = MI->getOperand(i);
+  for (MachineOperand &MO : MI->operands()) {
     if (!MO.isReg() || !MO.isUse())
       continue;
     unsigned Reg = MO.getReg();
@@ -186,8 +185,7 @@ MachineCSE::isPhysDefTriviallyDead(unsigned Reg,
       return true;
 
     bool SeenDef = false;
-    for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
-      const MachineOperand &MO = I->getOperand(i);
+    for (const MachineOperand &MO : I->operands()) {
       if (MO.isRegMask() && MO.clobbersPhysReg(Reg))
         SeenDef = true;
       if (!MO.isReg() || !MO.getReg())
@@ -220,8 +218,7 @@ bool MachineCSE::hasLivePhysRegDefUses(const MachineInstr *MI,
                                        SmallVectorImpl<unsigned> &PhysDefs,
                                        bool &PhysUseDef) const{
   // First, add all uses to PhysRefs.
-  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-    const MachineOperand &MO = MI->getOperand(i);
+  for (const MachineOperand &MO : MI->operands()) {
     if (!MO.isReg() || MO.isDef())
       continue;
     unsigned Reg = MO.getReg();
@@ -239,8 +236,7 @@ bool MachineCSE::hasLivePhysRegDefUses(const MachineInstr *MI,
   // (which currently contains only uses), set the PhysUseDef flag.
   PhysUseDef = false;
   MachineBasicBlock::const_iterator I = MI; I = std::next(I);
-  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-    const MachineOperand &MO = MI->getOperand(i);
+  for (const MachineOperand &MO : MI->operands()) {
     if (!MO.isReg() || !MO.isDef())
       continue;
     unsigned Reg = MO.getReg();
@@ -311,8 +307,7 @@ bool MachineCSE::PhysRegDefsReach(MachineInstr *CSMI, MachineInstr *MI,
     if (I == E)
       return true;
 
-    for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
-      const MachineOperand &MO = I->getOperand(i);
+    for (const MachineOperand &MO : I->operands()) {
       // RegMasks go on instructions like calls that clobber lots of physregs.
       // Don't attempt to CSE across such an instruction.
       if (MO.isRegMask())
@@ -398,8 +393,7 @@ bool MachineCSE::isProfitableToCSE(unsigned CSReg, unsigned Reg,
   // Heuristics #2: If the expression doesn't not use a vr and the only use
   // of the redundant computation are copies, do not cse.
   bool HasVRegUse = false;
-  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
-    const MachineOperand &MO = MI->getOperand(i);
+  for (const MachineOperand &MO : MI->operands()) {
     if (MO.isReg() && MO.isUse() &&
         TargetRegisterInfo::isVirtualRegister(MO.getReg())) {
       HasVRegUse = true;
@@ -580,9 +574,9 @@ bool MachineCSE::ProcessBlock(MachineBasicBlock *MBB) {
 
     // Actually perform the elimination.
     if (DoCSE) {
-      for (unsigned i = 0, e = CSEPairs.size(); i != e; ++i) {
-        unsigned OldReg = CSEPairs[i].first;
-        unsigned NewReg = CSEPairs[i].second;
+      for (std::pair<unsigned, unsigned> &CSEPair : CSEPairs) {
+        unsigned OldReg = CSEPair.first;
+        unsigned NewReg = CSEPair.second;
         // OldReg may have been unused but is used now, clear the Dead flag
         MachineInstr *Def = MRI->getUniqueVRegDef(NewReg);
         assert(Def != nullptr && "CSEd register has no unique definition?");
@@ -594,8 +588,8 @@ bool MachineCSE::ProcessBlock(MachineBasicBlock *MBB) {
 
       // Go through implicit defs of CSMI and MI, if a def is not dead at MI,
       // we should make sure it is not dead at CSMI.
-      for (unsigned i = 0, e = ImplicitDefsToUpdate.size(); i != e; ++i)
-        CSMI->getOperand(ImplicitDefsToUpdate[i]).setIsDead(false);
+      for (unsigned ImplicitDefToUpdate : ImplicitDefsToUpdate)
+        CSMI->getOperand(ImplicitDefToUpdate).setIsDead(false);
 
       // Go through implicit defs of CSMI and MI, and clear the kill flags on
       // their uses in all the instructions between CSMI and MI.
@@ -685,18 +679,14 @@ bool MachineCSE::PerformCSE(MachineDomTreeNode *Node) {
     Node = WorkList.pop_back_val();
     Scopes.push_back(Node);
     const std::vector<MachineDomTreeNode*> &Children = Node->getChildren();
-    unsigned NumChildren = Children.size();
-    OpenChildren[Node] = NumChildren;
-    for (unsigned i = 0; i != NumChildren; ++i) {
-      MachineDomTreeNode *Child = Children[i];
+    OpenChildren[Node] = Children.size();
+    for (MachineDomTreeNode *Child : Children)
       WorkList.push_back(Child);
-    }
   } while (!WorkList.empty());
 
   // Now perform CSE.
   bool Changed = false;
-  for (unsigned i = 0, e = Scopes.size(); i != e; ++i) {
-    MachineDomTreeNode *Node = Scopes[i];
+  for (MachineDomTreeNode *Node : Scopes) {
     MachineBasicBlock *MBB = Node->getBlock();
     EnterScope(MBB);
     Changed |= ProcessBlock(MBB);