X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FMachineBasicBlock.cpp;h=888c20e3a7c77cb0286bb9838e067bda65199ca1;hb=fabe5ce5661e096114b6a4cc978d312a1f7a8e7f;hp=df1c7c2a66da24cd28190fc0900f1328dfa3f469;hpb=dd58fa4869f9bff909720aaa428487a20fab1391;p=oota-llvm.git

diff --git a/lib/CodeGen/MachineBasicBlock.cpp b/lib/CodeGen/MachineBasicBlock.cpp
index df1c7c2a66d..888c20e3a7c 100644
--- a/lib/CodeGen/MachineBasicBlock.cpp
+++ b/lib/CodeGen/MachineBasicBlock.cpp
@@ -14,20 +14,20 @@
 #include "llvm/CodeGen/MachineBasicBlock.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallString.h"
-#include "llvm/Assembly/Writer.h"
 #include "llvm/CodeGen/LiveIntervalAnalysis.h"
 #include "llvm/CodeGen/LiveVariables.h"
 #include "llvm/CodeGen/MachineDominators.h"
 #include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineLoopInfo.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/CodeGen/SlotIndexes.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/DataLayout.h"
+#include "llvm/IR/LeakDetector.h"
 #include "llvm/MC/MCAsmInfo.h"
 #include "llvm/MC/MCContext.h"
 #include "llvm/Support/Debug.h"
-#include "llvm/Support/LeakDetector.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Target/TargetInstrInfo.h"
 #include "llvm/Target/TargetMachine.h"
@@ -37,7 +37,7 @@ using namespace llvm;
 
 MachineBasicBlock::MachineBasicBlock(MachineFunction &mf, const BasicBlock *bb)
   : BB(bb), Number(-1), xParent(&mf), Alignment(0), IsLandingPad(false),
-    AddressTaken(false) {
+    AddressTaken(false), CachedMCSymbol(NULL) {
   Insts.Parent = this;
 }
 
@@ -48,12 +48,17 @@ MachineBasicBlock::~MachineBasicBlock() {
 /// getSymbol - Return the MCSymbol for this basic block.
 ///
 MCSymbol *MachineBasicBlock::getSymbol() const {
-  const MachineFunction *MF = getParent();
-  MCContext &Ctx = MF->getContext();
-  const char *Prefix = Ctx.getAsmInfo().getPrivateGlobalPrefix();
-  return Ctx.GetOrCreateSymbol(Twine(Prefix) + "BB" +
-                               Twine(MF->getFunctionNumber()) + "_" +
-                               Twine(getNumber()));
+  if (!CachedMCSymbol) {
+    const MachineFunction *MF = getParent();
+    MCContext &Ctx = MF->getContext();
+    const TargetMachine &TM = MF->getTarget();
+    const char *Prefix = TM.getDataLayout()->getPrivateGlobalPrefix();
+    CachedMCSymbol = Ctx.GetOrCreateSymbol(Twine(Prefix) + "BB" +
+                                           Twine(MF->getFunctionNumber()) +
+                                           "_" + Twine(getNumber()));
+  }
+
+  return CachedMCSymbol;
 }
 
 
@@ -155,7 +160,7 @@ MachineBasicBlock::iterator MachineBasicBlock::getFirstNonPHI() {
 MachineBasicBlock::iterator
 MachineBasicBlock::SkipPHIsAndLabels(MachineBasicBlock::iterator I) {
   iterator E = end();
-  while (I != E && (I->isPHI() || I->isLabel() || I->isDebugValue()))
+  while (I != E && (I->isPHI() || I->isPosition() || I->isDebugValue()))
     ++I;
   // FIXME: This needs to change if we wish to bundle labels / dbg_values
   // inside the bundle.
@@ -272,7 +277,7 @@ void MachineBasicBlock::print(raw_ostream &OS, SlotIndexes *Indexes) const {
   const char *Comma = "";
   if (const BasicBlock *LBB = getBasicBlock()) {
     OS << Comma << "derived from LLVM BB ";
-    WriteAsOperand(OS, LBB, /*PrintType=*/false);
+    LBB->printAsOperand(OS, /*PrintType=*/false);
     Comma = ", ";
   }
   if (isLandingPad()) { OS << Comma << "EH LANDING PAD"; Comma = ", "; }
@@ -325,6 +330,10 @@ void MachineBasicBlock::print(raw_ostream &OS, SlotIndexes *Indexes) const {
   }
 }
 
+void MachineBasicBlock::printAsOperand(raw_ostream &OS, bool /*PrintType*/) {
+  OS << "BB#" << getNumber();
+}
+
 void MachineBasicBlock::removeLiveIn(unsigned Reg) {
   std::vector<unsigned>::iterator I =
     std::find(LiveIns.begin(), LiveIns.end(), Reg);
@@ -337,6 +346,38 @@ bool MachineBasicBlock::isLiveIn(unsigned Reg) const {
   return I != livein_end();
 }
 
+unsigned
+MachineBasicBlock::addLiveIn(unsigned PhysReg, const TargetRegisterClass *RC) {
+  assert(getParent() && "MBB must be inserted in function");
+  assert(TargetRegisterInfo::isPhysicalRegister(PhysReg) && "Expected physreg");
+  assert(RC && "Register class is required");
+  assert((isLandingPad() || this == &getParent()->front()) &&
+         "Only the entry block and landing pads can have physreg live ins");
+
+  bool LiveIn = isLiveIn(PhysReg);
+  iterator I = SkipPHIsAndLabels(begin()), E = end();
+  MachineRegisterInfo &MRI = getParent()->getRegInfo();
+  const TargetInstrInfo &TII = *getParent()->getTarget().getInstrInfo();
+
+  // Look for an existing copy.
+  if (LiveIn)
+    for (;I != E && I->isCopy(); ++I)
+      if (I->getOperand(1).getReg() == PhysReg) {
+        unsigned VirtReg = I->getOperand(0).getReg();
+        if (!MRI.constrainRegClass(VirtReg, RC))
+          llvm_unreachable("Incompatible live-in register class.");
+        return VirtReg;
+      }
+
+  // No luck, create a virtual register.
+  unsigned VirtReg = MRI.createVirtualRegister(RC);
+  BuildMI(*this, I, DebugLoc(), TII.get(TargetOpcode::COPY), VirtReg)
+    .addReg(PhysReg, RegState::Kill);
+  if (!LiveIn)
+    addLiveIn(PhysReg);
+  return VirtReg;
+}
+
 void MachineBasicBlock::moveBefore(MachineBasicBlock *NewAfter) {
   getParent()->splice(NewAfter, this);
 }
@@ -585,7 +626,7 @@ bool MachineBasicBlock::isSuccessor(const MachineBasicBlock *MBB) const {
 
 bool MachineBasicBlock::isLayoutSuccessor(const MachineBasicBlock *MBB) const {
   MachineFunction::const_iterator I(this);
-  return llvm::next(I) == MachineFunction::const_iterator(MBB);
+  return std::next(I) == MachineFunction::const_iterator(MBB);
 }
 
 bool MachineBasicBlock::canFallThrough() {
@@ -640,6 +681,11 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
   MachineFunction *MF = getParent();
   DebugLoc dl;  // FIXME: this is nowhere
 
+  // Performance might be harmed on HW that implements branching using exec mask
+  // where both sides of the branches are always executed.
+  if (MF->getTarget().requiresStructuredCFG())
+    return NULL;
+
   // We may need to update this's terminator, but we can't do that if
   // AnalyzeBranch fails. If this uses a jump table, we won't touch it.
   const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
@@ -659,7 +705,7 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
   }
 
   MachineBasicBlock *NMBB = MF->CreateMachineBasicBlock();
-  MF->insert(llvm::next(MachineFunction::iterator(this)), NMBB);
+  MF->insert(std::next(MachineFunction::iterator(this)), NMBB);
   DEBUG(dbgs() << "Splitting critical edge:"
         " BB#" << getNumber()
         << " -- BB#" << NMBB->getNumber()
@@ -698,6 +744,24 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
       }
     }
 
+  SmallVector<unsigned, 4> UsedRegs;
+  if (LIS) {
+    for (instr_iterator I = getFirstInstrTerminator(), E = instr_end();
+         I != E; ++I) {
+      MachineInstr *MI = I;
+
+      for (MachineInstr::mop_iterator OI = MI->operands_begin(),
+           OE = MI->operands_end(); OI != OE; ++OI) {
+        if (!OI->isReg() || OI->getReg() == 0)
+          continue;
+
+        unsigned Reg = OI->getReg();
+        if (std::find(UsedRegs.begin(), UsedRegs.end(), Reg) == UsedRegs.end())
+          UsedRegs.push_back(Reg);
+      }
+    }
+  }
+
   ReplaceUsesOfBlockWith(Succ, NMBB);
 
   // If updateTerminator() removes instructions, we need to remove them from
@@ -784,7 +848,7 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
     // extend to the end of the new split block.
 
     bool isLastMBB =
-      llvm::next(MachineFunction::iterator(NMBB)) == getParent()->end();
+      std::next(MachineFunction::iterator(NMBB)) == getParent()->end();
 
     SlotIndex StartIndex = Indexes->getMBBEndIdx(this);
     SlotIndex PrevIndex = StartIndex.getPrevSlot();
@@ -806,7 +870,7 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
           LiveInterval &LI = LIS->getInterval(Reg);
           VNInfo *VNI = LI.getVNInfoAt(PrevIndex);
           assert(VNI && "PHI sources should be live out of their predecessors.");
-          LI.addRange(LiveRange(StartIndex, EndIndex, VNI));
+          LI.addSegment(LiveInterval::Segment(StartIndex, EndIndex, VNI));
         }
       }
     }
@@ -825,11 +889,15 @@ MachineBasicBlock::SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P) {
       if (isLiveOut && isLastMBB) {
         VNInfo *VNI = LI.getVNInfoAt(PrevIndex);
         assert(VNI && "LiveInterval should have VNInfo where it is live.");
-        LI.addRange(LiveRange(StartIndex, EndIndex, VNI));
+        LI.addSegment(LiveInterval::Segment(StartIndex, EndIndex, VNI));
       } else if (!isLiveOut && !isLastMBB) {
-        LI.removeRange(StartIndex, EndIndex);
+        LI.removeSegment(StartIndex, EndIndex);
       }
     }
+
+    // Update all intervals for registers whose uses may have been modified by
+    // updateTerminator().
+    LIS->repairIntervalsInRange(this, getFirstTerminator(), end(), UsedRegs);
   }
 
   if (MachineDominatorTree *MDT =
@@ -995,7 +1063,7 @@ bool MachineBasicBlock::CorrectExtraCFGEdges(MachineBasicBlock *DestA,
   bool Changed = false;
 
   MachineFunction::iterator FallThru =
-    llvm::next(MachineFunction::iterator(this));
+    std::next(MachineFunction::iterator(this));
 
   if (DestA == 0 && DestB == 0) {
     // Block falls through to successor.
@@ -1055,6 +1123,13 @@ uint32_t MachineBasicBlock::getSuccWeight(const_succ_iterator Succ) const {
   return *getWeightIterator(Succ);
 }
 
+/// Set successor weight of a given iterator.
+void MachineBasicBlock::setSuccWeight(succ_iterator I, uint32_t weight) {
+  if (Weights.empty())
+    return;
+  *getWeightIterator(I) = weight;
+}
+
 /// getWeightIterator - Return wight iterator corresonding to the I successor
 /// iterator
 MachineBasicBlock::weight_iterator MachineBasicBlock::
@@ -1151,9 +1226,3 @@ MachineBasicBlock::computeRegisterLiveness(const TargetRegisterInfo *TRI,
   // At this point we have no idea of the liveness of the register.
   return LQR_Unknown;
 }
-
-void llvm::WriteAsOperand(raw_ostream &OS, const MachineBasicBlock *MBB,
-                          bool t) {
-  OS << "BB#" << MBB->getNumber();
-}
-