[ValueTracking] Move GlobalAlias handling to be after the max depth check in computeK...

[oota-llvm.git] / lib / CodeGen / PHIElimination.cpp

diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index b104eb4590877e8bf3238fc85215658495340871..def2e3d48ac0cfe01e1b90acbb90445533193dfb 100644 (file)
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -13,7 +13,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "phielim"
 #include "llvm/CodeGen/Passes.h"
 #include "PHIEliminationUtils.h"
 #include "llvm/ADT/STLExtras.h"
@@ -31,10 +30,12 @@
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Target/TargetInstrInfo.h"
-#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
 #include <algorithm>
 using namespace llvm;
 
+#define DEBUG_TYPE "phielim"
+
 static cl::opt<bool>
 DisableEdgeSplitting("disable-phi-elim-edge-splitting", cl::init(false),
                      cl::Hidden, cl::desc("Disable critical edge splitting "
@@ -57,8 +58,8 @@ namespace {
       initializePHIEliminationPass(*PassRegistry::getPassRegistry());
     }
 
-    virtual bool runOnMachineFunction(MachineFunction &Fn);
-    virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+    bool runOnMachineFunction(MachineFunction &Fn) override;
+    void getAnalysisUsage(AnalysisUsage &AU) const override;
 
   private:
     /// EliminatePHINodes - Eliminate phi nodes by inserting copy instructions
@@ -149,9 +150,7 @@ bool PHIElimination::runOnMachineFunction(MachineFunction &MF) {
     Changed |= EliminatePHINodes(MF, *I);
 
   // Remove dead IMPLICIT_DEF instructions.
-  for (SmallPtrSet<MachineInstr*, 4>::iterator I = ImpDefs.begin(),
-         E = ImpDefs.end(); I != E; ++I) {
-    MachineInstr *DefMI = *I;
+  for (MachineInstr *DefMI : ImpDefs) {
     unsigned DefReg = DefMI->getOperand(0).getReg();
     if (MRI->use_nodbg_empty(DefReg)) {
       if (LIS)
@@ -198,9 +197,8 @@ bool PHIElimination::EliminatePHINodes(MachineFunction &MF,
 /// This includes registers with no defs.
 static bool isImplicitlyDefined(unsigned VirtReg,
                                 const MachineRegisterInfo *MRI) {
-  for (MachineRegisterInfo::def_iterator DI = MRI->def_begin(VirtReg),
-       DE = MRI->def_end(); DI != DE; ++DI)
-    if (!DI->isImplicitDef())
+  for (MachineInstr &DI : MRI->def_instructions(VirtReg))
+    if (!DI.isImplicitDef())
       return false;
   return true;
 }
@@ -240,7 +238,7 @@ void PHIElimination::LowerPHINode(MachineBasicBlock &MBB,
   // Insert a register to register copy at the top of the current block (but
   // after any remaining phi nodes) which copies the new incoming register
   // into the phi node destination.
-  const TargetInstrInfo *TII = MF.getTarget().getInstrInfo();
+  const TargetInstrInfo *TII = MF.getSubtarget().getInstrInfo();
   if (isSourceDefinedByImplicitDef(MPhi, MRI))
     // If all sources of a PHI node are implicit_def, just emit an
     // implicit_def instead of a copy.
@@ -369,7 +367,7 @@ void PHIElimination::LowerPHINode(MachineBasicBlock &MBB,
     // Check to make sure we haven't already emitted the copy for this block.
     // This can happen because PHI nodes may have multiple entries for the same
     // basic block.
-    if (!MBBsInsertedInto.insert(&opBlock))
+    if (!MBBsInsertedInto.insert(&opBlock).second)
       continue;  // If the copy has already been emitted, we're done.
 
     // Find a safe location to insert the copy, this may be the first terminator
@@ -378,7 +376,7 @@ void PHIElimination::LowerPHINode(MachineBasicBlock &MBB,
       findPHICopyInsertPoint(&opBlock, &MBB, SrcReg);
 
     // Insert the copy.
-    MachineInstr *NewSrcInstr = 0;
+    MachineInstr *NewSrcInstr = nullptr;
     if (!reusedIncoming && IncomingReg) {
       if (SrcUndef) {
         // The source register is undefined, so there is no need for a real
@@ -532,13 +530,14 @@ void PHIElimination::LowerPHINode(MachineBasicBlock &MBB,
 /// used later to determine when the vreg is killed in the BB.
 ///
 void PHIElimination::analyzePHINodes(const MachineFunction& MF) {
-  for (MachineFunction::const_iterator I = MF.begin(), E = MF.end();
-       I != E; ++I)
-    for (MachineBasicBlock::const_iterator BBI = I->begin(), BBE = I->end();
-         BBI != BBE && BBI->isPHI(); ++BBI)
-      for (unsigned i = 1, e = BBI->getNumOperands(); i != e; i += 2)
-        ++VRegPHIUseCount[BBVRegPair(BBI->getOperand(i+1).getMBB()->getNumber(),
-                                     BBI->getOperand(i).getReg())];
+  for (const auto &MBB : MF)
+    for (const auto &BBI : MBB) {
+      if (!BBI.isPHI())
+        break;
+      for (unsigned i = 1, e = BBI.getNumOperands(); i != e; i += 2)
+        ++VRegPHIUseCount[BBVRegPair(BBI.getOperand(i+1).getMBB()->getNumber(),
+                                     BBI.getOperand(i).getReg())];
+    }
 }
 
 bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
@@ -547,7 +546,7 @@ bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
   if (MBB.empty() || !MBB.front().isPHI() || MBB.isLandingPad())
     return false;   // Quick exit for basic blocks without PHIs.
 
-  const MachineLoop *CurLoop = MLI ? MLI->getLoopFor(&MBB) : 0;
+  const MachineLoop *CurLoop = MLI ? MLI->getLoopFor(&MBB) : nullptr;
   bool IsLoopHeader = CurLoop && &MBB == CurLoop->getHeader();
 
   bool Changed = false;
@@ -564,7 +563,7 @@ bool PHIElimination::SplitPHIEdges(MachineFunction &MF,
       // out-of-line blocks into the loop which is very bad for code placement.
       if (PreMBB == &MBB && !SplitAllCriticalEdges)
         continue;
-      const MachineLoop *PreLoop = MLI ? MLI->getLoopFor(PreMBB) : 0;
+      const MachineLoop *PreLoop = MLI ? MLI->getLoopFor(PreMBB) : nullptr;
       if (IsLoopHeader && PreLoop == CurLoop && !SplitAllCriticalEdges)
         continue;