Import LLVM, at r72732.vendor/llvm/llvm-r72732

1 files changed, 372 insertions, 0 deletions

diff --git a/lib/CodeGen/MachineBasicBlock.cpp b/lib/CodeGen/MachineBasicBlock.cpp
new file mode 100644
index 000000000000..71e6b3e4d0f8
--- /dev/null
+++ b/lib/CodeGen/MachineBasicBlock.cpp
@@ -0,0 +1,372 @@
+//===-- llvm/CodeGen/MachineBasicBlock.cpp ----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Collect the sequence of machine instructions for a basic block.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/BasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetInstrDesc.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/LeakDetector.h"
+#include <algorithm>
+using namespace llvm;
+
+MachineBasicBlock::MachineBasicBlock(MachineFunction &mf, const BasicBlock *bb)
+  : BB(bb), Number(-1), xParent(&mf), Alignment(0), IsLandingPad(false) {
+  Insts.Parent = this;
+}
+
+MachineBasicBlock::~MachineBasicBlock() {
+  LeakDetector::removeGarbageObject(this);
+}
+
+std::ostream& llvm::operator<<(std::ostream &OS, const MachineBasicBlock &MBB) {
+  MBB.print(OS);
+  return OS;
+}
+
+/// addNodeToList (MBB) - When an MBB is added to an MF, we need to update the 
+/// parent pointer of the MBB, the MBB numbering, and any instructions in the
+/// MBB to be on the right operand list for registers.
+///
+/// MBBs start out as #-1. When a MBB is added to a MachineFunction, it
+/// gets the next available unique MBB number. If it is removed from a
+/// MachineFunction, it goes back to being #-1.
+void ilist_traits<MachineBasicBlock>::addNodeToList(MachineBasicBlock* N) {
+  MachineFunction &MF = *N->getParent();
+  N->Number = MF.addToMBBNumbering(N);
+
+  // Make sure the instructions have their operands in the reginfo lists.
+  MachineRegisterInfo &RegInfo = MF.getRegInfo();
+  for (MachineBasicBlock::iterator I = N->begin(), E = N->end(); I != E; ++I)
+    I->AddRegOperandsToUseLists(RegInfo);
+
+  LeakDetector::removeGarbageObject(N);
+}
+
+void ilist_traits<MachineBasicBlock>::removeNodeFromList(MachineBasicBlock* N) {
+  N->getParent()->removeFromMBBNumbering(N->Number);
+  N->Number = -1;
+  LeakDetector::addGarbageObject(N);
+}
+
+
+/// addNodeToList (MI) - When we add an instruction to a basic block
+/// list, we update its parent pointer and add its operands from reg use/def
+/// lists if appropriate.
+void ilist_traits<MachineInstr>::addNodeToList(MachineInstr* N) {
+  assert(N->getParent() == 0 && "machine instruction already in a basic block");
+  N->setParent(Parent);
+  
+  // Add the instruction's register operands to their corresponding
+  // use/def lists.
+  MachineFunction *MF = Parent->getParent();
+  N->AddRegOperandsToUseLists(MF->getRegInfo());
+
+  LeakDetector::removeGarbageObject(N);
+}
+
+/// removeNodeFromList (MI) - When we remove an instruction from a basic block
+/// list, we update its parent pointer and remove its operands from reg use/def
+/// lists if appropriate.
+void ilist_traits<MachineInstr>::removeNodeFromList(MachineInstr* N) {
+  assert(N->getParent() != 0 && "machine instruction not in a basic block");
+
+  // Remove from the use/def lists.
+  N->RemoveRegOperandsFromUseLists();
+  
+  N->setParent(0);
+
+  LeakDetector::addGarbageObject(N);
+}
+
+/// transferNodesFromList (MI) - When moving a range of instructions from one
+/// MBB list to another, we need to update the parent pointers and the use/def
+/// lists.
+void ilist_traits<MachineInstr>::transferNodesFromList(
+      ilist_traits<MachineInstr>& fromList,
+      MachineBasicBlock::iterator first,
+      MachineBasicBlock::iterator last) {
+  assert(Parent->getParent() == fromList.Parent->getParent() &&
+        "MachineInstr parent mismatch!");
+
+  // Splice within the same MBB -> no change.
+  if (Parent == fromList.Parent) return;
+
+  // If splicing between two blocks within the same function, just update the
+  // parent pointers.
+  for (; first != last; ++first)
+    first->setParent(Parent);
+}
+
+void ilist_traits<MachineInstr>::deleteNode(MachineInstr* MI) {
+  assert(!MI->getParent() && "MI is still in a block!");
+  Parent->getParent()->DeleteMachineInstr(MI);
+}
+
+MachineBasicBlock::iterator MachineBasicBlock::getFirstTerminator() {
+  iterator I = end();
+  while (I != begin() && (--I)->getDesc().isTerminator())
+    ; /*noop */
+  if (I != end() && !I->getDesc().isTerminator()) ++I;
+  return I;
+}
+
+bool
+MachineBasicBlock::isOnlyReachableByFallthrough() const {
+  return !isLandingPad() &&
+         !pred_empty() &&
+         next(pred_begin()) == pred_end() &&
+         (*pred_begin())->isLayoutSuccessor(this) &&
+         ((*pred_begin())->empty() ||
+          !(*pred_begin())->back().getDesc().isBarrier());
+}
+
+void MachineBasicBlock::dump() const {
+  print(*cerr.stream());
+}
+
+static inline void OutputReg(std::ostream &os, unsigned RegNo,
+                             const TargetRegisterInfo *TRI = 0) {
+  if (!RegNo || TargetRegisterInfo::isPhysicalRegister(RegNo)) {
+    if (TRI)
+      os << " %" << TRI->get(RegNo).Name;
+    else
+      os << " %mreg(" << RegNo << ")";
+  } else
+    os << " %reg" << RegNo;
+}
+
+void MachineBasicBlock::print(std::ostream &OS) const {
+  const MachineFunction *MF = getParent();
+  if(!MF) {
+    OS << "Can't print out MachineBasicBlock because parent MachineFunction"
+       << " is null\n";
+    return;
+  }
+
+  const BasicBlock *LBB = getBasicBlock();
+  OS << "\n";
+  if (LBB) OS << LBB->getName() << ": ";
+  OS << (const void*)this
+     << ", LLVM BB @" << (const void*) LBB << ", ID#" << getNumber();
+  if (Alignment) OS << ", Alignment " << Alignment;
+  if (isLandingPad()) OS << ", EH LANDING PAD";
+  OS << ":\n";
+
+  const TargetRegisterInfo *TRI = MF->getTarget().getRegisterInfo();  
+  if (!livein_empty()) {
+    OS << "Live Ins:";
+    for (const_livein_iterator I = livein_begin(),E = livein_end(); I != E; ++I)
+      OutputReg(OS, *I, TRI);
+    OS << "\n";
+  }
+  // Print the preds of this block according to the CFG.
+  if (!pred_empty()) {
+    OS << "    Predecessors according to CFG:";
+    for (const_pred_iterator PI = pred_begin(), E = pred_end(); PI != E; ++PI)
+      OS << " " << *PI << " (#" << (*PI)->getNumber() << ")";
+    OS << "\n";
+  }
+  
+  for (const_iterator I = begin(); I != end(); ++I) {
+    OS << "\t";
+    I->print(OS, &getParent()->getTarget());
+  }
+
+  // Print the successors of this block according to the CFG.
+  if (!succ_empty()) {
+    OS << "    Successors according to CFG:";
+    for (const_succ_iterator SI = succ_begin(), E = succ_end(); SI != E; ++SI)
+      OS << " " << *SI << " (#" << (*SI)->getNumber() << ")";
+    OS << "\n";
+  }
+}
+
+void MachineBasicBlock::removeLiveIn(unsigned Reg) {
+  livein_iterator I = std::find(livein_begin(), livein_end(), Reg);
+  assert(I != livein_end() && "Not a live in!");
+  LiveIns.erase(I);
+}
+
+bool MachineBasicBlock::isLiveIn(unsigned Reg) const {
+  const_livein_iterator I = std::find(livein_begin(), livein_end(), Reg);
+  return I != livein_end();
+}
+
+void MachineBasicBlock::moveBefore(MachineBasicBlock *NewAfter) {
+  getParent()->splice(NewAfter, this);
+}
+
+void MachineBasicBlock::moveAfter(MachineBasicBlock *NewBefore) {
+  MachineFunction::iterator BBI = NewBefore;
+  getParent()->splice(++BBI, this);
+}
+
+
+void MachineBasicBlock::addSuccessor(MachineBasicBlock *succ) {
+  Successors.push_back(succ);
+  succ->addPredecessor(this);
+}
+
+void MachineBasicBlock::removeSuccessor(MachineBasicBlock *succ) {
+  succ->removePredecessor(this);
+  succ_iterator I = std::find(Successors.begin(), Successors.end(), succ);
+  assert(I != Successors.end() && "Not a current successor!");
+  Successors.erase(I);
+}
+
+MachineBasicBlock::succ_iterator 
+MachineBasicBlock::removeSuccessor(succ_iterator I) {
+  assert(I != Successors.end() && "Not a current successor!");
+  (*I)->removePredecessor(this);
+  return Successors.erase(I);
+}
+
+void MachineBasicBlock::addPredecessor(MachineBasicBlock *pred) {
+  Predecessors.push_back(pred);
+}
+
+void MachineBasicBlock::removePredecessor(MachineBasicBlock *pred) {
+  std::vector<MachineBasicBlock *>::iterator I =
+    std::find(Predecessors.begin(), Predecessors.end(), pred);
+  assert(I != Predecessors.end() && "Pred is not a predecessor of this block!");
+  Predecessors.erase(I);
+}
+
+void MachineBasicBlock::transferSuccessors(MachineBasicBlock *fromMBB)
+{
+  if (this == fromMBB)
+    return;
+  
+  for(MachineBasicBlock::succ_iterator iter = fromMBB->succ_begin(), 
+      end = fromMBB->succ_end(); iter != end; ++iter) {
+      addSuccessor(*iter);
+  }
+  while(!fromMBB->succ_empty())
+    fromMBB->removeSuccessor(fromMBB->succ_begin());
+}
+
+bool MachineBasicBlock::isSuccessor(const MachineBasicBlock *MBB) const {
+  std::vector<MachineBasicBlock *>::const_iterator I =
+    std::find(Successors.begin(), Successors.end(), MBB);
+  return I != Successors.end();
+}
+
+bool MachineBasicBlock::isLayoutSuccessor(const MachineBasicBlock *MBB) const {
+  MachineFunction::const_iterator I(this);
+  return next(I) == MachineFunction::const_iterator(MBB);
+}
+
+/// removeFromParent - This method unlinks 'this' from the containing function,
+/// and returns it, but does not delete it.
+MachineBasicBlock *MachineBasicBlock::removeFromParent() {
+  assert(getParent() && "Not embedded in a function!");
+  getParent()->remove(this);
+  return this;
+}
+
+
+/// eraseFromParent - This method unlinks 'this' from the containing function,
+/// and deletes it.
+void MachineBasicBlock::eraseFromParent() {
+  assert(getParent() && "Not embedded in a function!");
+  getParent()->erase(this);
+}
+
+
+/// ReplaceUsesOfBlockWith - Given a machine basic block that branched to
+/// 'Old', change the code and CFG so that it branches to 'New' instead.
+void MachineBasicBlock::ReplaceUsesOfBlockWith(MachineBasicBlock *Old,
+                                               MachineBasicBlock *New) {
+  assert(Old != New && "Cannot replace self with self!");
+
+  MachineBasicBlock::iterator I = end();
+  while (I != begin()) {
+    --I;
+    if (!I->getDesc().isTerminator()) break;
+
+    // Scan the operands of this machine instruction, replacing any uses of Old
+    // with New.
+    for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i)
+      if (I->getOperand(i).isMBB() &&
+          I->getOperand(i).getMBB() == Old)
+        I->getOperand(i).setMBB(New);
+  }
+
+  // Update the successor information.
+  removeSuccessor(Old);
+  addSuccessor(New);
+}
+
+/// CorrectExtraCFGEdges - Various pieces of code can cause excess edges in the
+/// CFG to be inserted.  If we have proven that MBB can only branch to DestA and
+/// DestB, remove any other MBB successors from the CFG.  DestA and DestB can
+/// be null.
+/// Besides DestA and DestB, retain other edges leading to LandingPads
+/// (currently there can be only one; we don't check or require that here).
+/// Note it is possible that DestA and/or DestB are LandingPads.
+bool MachineBasicBlock::CorrectExtraCFGEdges(MachineBasicBlock *DestA,
+                                             MachineBasicBlock *DestB,
+                                             bool isCond) {
+  bool MadeChange = false;
+  bool AddedFallThrough = false;
+
+  MachineFunction::iterator FallThru = next(MachineFunction::iterator(this));
+  
+  // If this block ends with a conditional branch that falls through to its
+  // successor, set DestB as the successor.
+  if (isCond) {
+    if (DestB == 0 && FallThru != getParent()->end()) {
+      DestB = FallThru;
+      AddedFallThrough = true;
+    }
+  } else {
+    // If this is an unconditional branch with no explicit dest, it must just be
+    // a fallthrough into DestB.
+    if (DestA == 0 && FallThru != getParent()->end()) {
+      DestA = FallThru;
+      AddedFallThrough = true;
+    }
+  }
+  
+  MachineBasicBlock::succ_iterator SI = succ_begin();
+  MachineBasicBlock *OrigDestA = DestA, *OrigDestB = DestB;
+  while (SI != succ_end()) {
+    if (*SI == DestA && DestA == DestB) {
+      DestA = DestB = 0;
+      ++SI;
+    } else if (*SI == DestA) {
+      DestA = 0;
+      ++SI;
+    } else if (*SI == DestB) {
+      DestB = 0;
+      ++SI;
+    } else if ((*SI)->isLandingPad() && 
+               *SI!=OrigDestA && *SI!=OrigDestB) {
+      ++SI;
+    } else {
+      // Otherwise, this is a superfluous edge, remove it.
+      SI = removeSuccessor(SI);
+      MadeChange = true;
+    }
+  }
+  if (!AddedFallThrough) {
+    assert(DestA == 0 && DestB == 0 &&
+           "MachineCFG is missing edges!");
+  } else if (isCond) {
+    assert(DestA == 0 && "MachineCFG is missing edges!");
+  }
+  return MadeChange;
+}