Have MachineFunction cache a pointer to the subtarget to make lookups

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

diff --git a/lib/CodeGen/TailDuplication.cpp b/lib/CodeGen/TailDuplication.cpp
index df28c3938ad778af6d749a5d44ffc81432f184ec..4377236323a709fad4190910c504fa031b2615d3 100644 (file)
--- a/lib/CodeGen/TailDuplication.cpp
+++ b/lib/CodeGen/TailDuplication.cpp
@@ -12,7 +12,6 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "tailduplication"
 #include "llvm/CodeGen/Passes.h"
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/SetVector.h"
@@ -32,8 +31,11 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
 using namespace llvm;
 
+#define DEBUG_TYPE "tailduplication"
+
 STATISTIC(NumTails     , "Number of tails duplicated");
 STATISTIC(NumTailDups  , "Number of tail duplicated blocks");
 STATISTIC(NumInstrDups , "Additional instructions due to tail duplication");
@@ -131,8 +133,11 @@ INITIALIZE_PASS(TailDuplicatePass, "tailduplication", "Tail Duplication",
                 false, false)
 
 bool TailDuplicatePass::runOnMachineFunction(MachineFunction &MF) {
-  TII = MF.getTarget().getInstrInfo();
-  TRI = MF.getTarget().getRegisterInfo();
+  if (skipOptnoneFunction(*MF.getFunction()))
+    return false;
+
+  TII = MF.getSubtarget().getInstrInfo();
+  TRI = MF.getSubtarget().getRegisterInfo();
   MRI = &MF.getRegInfo();
   MMI = getAnalysisIfAvailable<MachineModuleInfo>();
   MBPI = &getAnalysis<MachineBranchProbabilityInfo>();
@@ -178,7 +183,7 @@ static void VerifyPHIs(MachineFunction &MF, bool CheckExtra) {
           dbgs() << "Malformed PHI in BB#" << MBB->getNumber() << ": " << *MI;
           dbgs() << "  missing input from predecessor BB#"
                  << PredBB->getNumber() << '\n';
-          llvm_unreachable(0);
+          llvm_unreachable(nullptr);
         }
       }
 
@@ -189,12 +194,12 @@ static void VerifyPHIs(MachineFunction &MF, bool CheckExtra) {
                  << ": " << *MI;
           dbgs() << "  extra input from predecessor BB#"
                  << PHIBB->getNumber() << '\n';
-          llvm_unreachable(0);
+          llvm_unreachable(nullptr);
         }
         if (PHIBB->getNumber() < 0) {
           dbgs() << "Malformed PHI in BB#" << MBB->getNumber() << ": " << *MI;
           dbgs() << "  non-existing BB#" << PHIBB->getNumber() << '\n';
-          llvm_unreachable(0);
+          llvm_unreachable(nullptr);
         }
       }
       ++MI;
@@ -244,7 +249,7 @@ TailDuplicatePass::TailDuplicateAndUpdate(MachineBasicBlock *MBB,
       // If the original definition is still around, add it as an available
       // value.
       MachineInstr *DefMI = MRI->getVRegDef(VReg);
-      MachineBasicBlock *DefBB = 0;
+      MachineBasicBlock *DefBB = nullptr;
       if (DefMI) {
         DefBB = DefMI->getParent();
         SSAUpdate.AddAvailableValue(DefBB, VReg);
@@ -338,12 +343,10 @@ bool TailDuplicatePass::TailDuplicateBlocks(MachineFunction &MF) {
 
 static bool isDefLiveOut(unsigned Reg, MachineBasicBlock *BB,
                          const MachineRegisterInfo *MRI) {
-  for (MachineRegisterInfo::use_instr_iterator UI = MRI->use_instr_begin(Reg),
-         UE = MRI->use_instr_end(); UI != UE; ++UI) {
-    MachineInstr *UseMI = &*UI;
-    if (UseMI->isDebugValue())
+  for (MachineInstr &UseMI : MRI->use_instructions(Reg)) {
+    if (UseMI.isDebugValue())
       continue;
-    if (UseMI->getParent() != BB)
+    if (UseMI.getParent() != BB)
       return true;
   }
   return false;
@@ -362,9 +365,7 @@ static unsigned getPHISrcRegOpIdx(MachineInstr *MI, MachineBasicBlock *SrcBB) {
 // block (which is why we need to copy the information).
 static void getRegsUsedByPHIs(const MachineBasicBlock &BB,
                               DenseSet<unsigned> *UsedByPhi) {
-  for(MachineBasicBlock::const_iterator I = BB.begin(), E = BB.end();
-      I != E; ++I) {
-    const MachineInstr &MI = *I;
+  for (const auto &MI : BB) {
     if (!MI.isPHI())
       break;
     for (unsigned i = 1, e = MI.getNumOperands(); i != e; i += 2) {
@@ -655,7 +656,7 @@ TailDuplicatePass::canCompletelyDuplicateBB(MachineBasicBlock &BB) {
     if (PredBB->succ_size() > 1)
       return false;
 
-    MachineBasicBlock *PredTBB = NULL, *PredFBB = NULL;
+    MachineBasicBlock *PredTBB = nullptr, *PredFBB = nullptr;
     SmallVector<MachineOperand, 4> PredCond;
     if (TII->AnalyzeBranch(*PredBB, PredTBB, PredFBB, PredCond, true))
       return false;
@@ -686,7 +687,7 @@ TailDuplicatePass::duplicateSimpleBB(MachineBasicBlock *TailBB,
     if (bothUsedInPHI(*PredBB, Succs))
       continue;
 
-    MachineBasicBlock *PredTBB = NULL, *PredFBB = NULL;
+    MachineBasicBlock *PredTBB = nullptr, *PredFBB = nullptr;
     SmallVector<MachineOperand, 4> PredCond;
     if (TII->AnalyzeBranch(*PredBB, PredTBB, PredFBB, PredCond, true))
       continue;
@@ -717,14 +718,14 @@ TailDuplicatePass::duplicateSimpleBB(MachineBasicBlock *TailBB,
     // Make the branch unconditional if possible
     if (PredTBB == PredFBB) {
       PredCond.clear();
-      PredFBB = NULL;
+      PredFBB = nullptr;
     }
 
     // Avoid adding fall through branches.
     if (PredFBB == NextBB)
-      PredFBB = NULL;
-    if (PredTBB == NextBB && PredFBB == NULL)
-      PredTBB = NULL;
+      PredFBB = nullptr;
+    if (PredTBB == NextBB && PredFBB == nullptr)
+      PredTBB = nullptr;
 
     TII->RemoveBranch(*PredBB);
 
@@ -798,11 +799,9 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB,
       RS->enterBasicBlock(PredBB);
       if (!PredBB->empty())
         RS->forward(std::prev(PredBB->end()));
-      BitVector RegsLiveAtExit(TRI->getNumRegs());
-      RS->getRegsUsed(RegsLiveAtExit, false);
       for (MachineBasicBlock::livein_iterator I = TailBB->livein_begin(),
              E = TailBB->livein_end(); I != E; ++I) {
-        if (!RegsLiveAtExit[*I])
+        if (!RS->isRegUsed(*I, false))
           // If a register is previously livein to the tail but it's not live
           // at the end of predecessor BB, then it should be added to its
           // livein list.
@@ -857,7 +856,7 @@ TailDuplicatePass::TailDuplicate(MachineBasicBlock *TailBB,
   // block, which falls through unconditionally, move the contents of this
   // block into the prior block.
   MachineBasicBlock *PrevBB = std::prev(MachineFunction::iterator(TailBB));
-  MachineBasicBlock *PriorTBB = 0, *PriorFBB = 0;
+  MachineBasicBlock *PriorTBB = nullptr, *PriorFBB = nullptr;
   SmallVector<MachineOperand, 4> PriorCond;
   // This has to check PrevBB->succ_size() because EH edges are ignored by
   // AnalyzeBranch.