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diff --git a/lib/Target/NVPTX/NVPTXPrologEpilogPass.cpp b/lib/Target/NVPTX/NVPTXPrologEpilogPass.cpp
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+++ b/lib/Target/NVPTX/NVPTXPrologEpilogPass.cpp
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+//===-- NVPTXPrologEpilogPass.cpp - NVPTX prolog/epilog inserter ----------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a copy of the generic LLVM PrologEpilogInserter pass, modified
+// to remove unneeded functionality and to handle virtual registers. Most code
+// here is a copy of PrologEpilogInserter.cpp.
+//
+//===----------------------------------------------------------------------===//
+
+#include "NVPTX.h"
+#include "llvm/Pass.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/Target/TargetFrameLowering.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Support/Debug.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+namespace {
+class NVPTXPrologEpilogPass : public MachineFunctionPass {
+public:
+  static char ID;
+  NVPTXPrologEpilogPass() : MachineFunctionPass(ID) {}
+
+  virtual bool runOnMachineFunction(MachineFunction &MF);
+
+private:
+  void calculateFrameObjectOffsets(MachineFunction &Fn);
+};
+}
+
+MachineFunctionPass *llvm::createNVPTXPrologEpilogPass() {
+  return new NVPTXPrologEpilogPass();
+}
+
+char NVPTXPrologEpilogPass::ID = 0;
+
+bool NVPTXPrologEpilogPass::runOnMachineFunction(MachineFunction &MF) {
+  const TargetMachine &TM = MF.getTarget();
+  const TargetFrameLowering &TFI = *TM.getFrameLowering();
+  const TargetRegisterInfo &TRI = *TM.getRegisterInfo();
+  bool Modified = false;
+
+  calculateFrameObjectOffsets(MF);
+
+  for (MachineFunction::iterator BB = MF.begin(), E = MF.end(); BB != E; ++BB) {
+    for (MachineBasicBlock::iterator I = BB->begin(); I != BB->end(); ++I) {
+      MachineInstr *MI = I;
+      for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
+        if (!MI->getOperand(i).isFI())
+          continue;
+        TRI.eliminateFrameIndex(MI, 0, i, NULL);
+        Modified = true;
+      }
+    }
+  }
+
+  // Add function prolog/epilog
+  TFI.emitPrologue(MF);
+
+  for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) {
+    // If last instruction is a return instruction, add an epilogue
+    if (!I->empty() && I->back().isReturn())
+      TFI.emitEpilogue(MF, *I);
+  }
+
+  return Modified;
+}
+
+/// AdjustStackOffset - Helper function used to adjust the stack frame offset.
+static inline void
+AdjustStackOffset(MachineFrameInfo *MFI, int FrameIdx,
+                  bool StackGrowsDown, int64_t &Offset,
+                  unsigned &MaxAlign) {
+  // If the stack grows down, add the object size to find the lowest address.
+  if (StackGrowsDown)
+    Offset += MFI->getObjectSize(FrameIdx);
+
+  unsigned Align = MFI->getObjectAlignment(FrameIdx);
+
+  // If the alignment of this object is greater than that of the stack, then
+  // increase the stack alignment to match.
+  MaxAlign = std::max(MaxAlign, Align);
+
+  // Adjust to alignment boundary.
+  Offset = (Offset + Align - 1) / Align * Align;
+
+  if (StackGrowsDown) {
+    DEBUG(dbgs() << "alloc FI(" << FrameIdx << ") at SP[" << -Offset << "]\n");
+    MFI->setObjectOffset(FrameIdx, -Offset); // Set the computed offset
+  } else {
+    DEBUG(dbgs() << "alloc FI(" << FrameIdx << ") at SP[" << Offset << "]\n");
+    MFI->setObjectOffset(FrameIdx, Offset);
+    Offset += MFI->getObjectSize(FrameIdx);
+  }
+}
+
+void
+NVPTXPrologEpilogPass::calculateFrameObjectOffsets(MachineFunction &Fn) {
+  const TargetFrameLowering &TFI = *Fn.getTarget().getFrameLowering();
+  const TargetRegisterInfo *RegInfo = Fn.getTarget().getRegisterInfo();
+
+  bool StackGrowsDown =
+    TFI.getStackGrowthDirection() == TargetFrameLowering::StackGrowsDown;
+
+  // Loop over all of the stack objects, assigning sequential addresses...
+  MachineFrameInfo *MFI = Fn.getFrameInfo();
+
+  // Start at the beginning of the local area.
+  // The Offset is the distance from the stack top in the direction
+  // of stack growth -- so it's always nonnegative.
+  int LocalAreaOffset = TFI.getOffsetOfLocalArea();
+  if (StackGrowsDown)
+    LocalAreaOffset = -LocalAreaOffset;
+  assert(LocalAreaOffset >= 0
+         && "Local area offset should be in direction of stack growth");
+  int64_t Offset = LocalAreaOffset;
+
+  // If there are fixed sized objects that are preallocated in the local area,
+  // non-fixed objects can't be allocated right at the start of local area.
+  // We currently don't support filling in holes in between fixed sized
+  // objects, so we adjust 'Offset' to point to the end of last fixed sized
+  // preallocated object.
+  for (int i = MFI->getObjectIndexBegin(); i != 0; ++i) {
+    int64_t FixedOff;
+    if (StackGrowsDown) {
+      // The maximum distance from the stack pointer is at lower address of
+      // the object -- which is given by offset. For down growing stack
+      // the offset is negative, so we negate the offset to get the distance.
+      FixedOff = -MFI->getObjectOffset(i);
+    } else {
+      // The maximum distance from the start pointer is at the upper
+      // address of the object.
+      FixedOff = MFI->getObjectOffset(i) + MFI->getObjectSize(i);
+    }
+    if (FixedOff > Offset) Offset = FixedOff;
+  }
+
+  // NOTE: We do not have a call stack
+
+  unsigned MaxAlign = MFI->getMaxAlignment();
+
+  // No scavenger
+
+  // FIXME: Once this is working, then enable flag will change to a target
+  // check for whether the frame is large enough to want to use virtual
+  // frame index registers. Functions which don't want/need this optimization
+  // will continue to use the existing code path.
+  if (MFI->getUseLocalStackAllocationBlock()) {
+    unsigned Align = MFI->getLocalFrameMaxAlign();
+
+    // Adjust to alignment boundary.
+    Offset = (Offset + Align - 1) / Align * Align;
+
+    DEBUG(dbgs() << "Local frame base offset: " << Offset << "\n");
+
+    // Resolve offsets for objects in the local block.
+    for (unsigned i = 0, e = MFI->getLocalFrameObjectCount(); i != e; ++i) {
+      std::pair<int, int64_t> Entry = MFI->getLocalFrameObjectMap(i);
+      int64_t FIOffset = (StackGrowsDown ? -Offset : Offset) + Entry.second;
+      DEBUG(dbgs() << "alloc FI(" << Entry.first << ") at SP[" <<
+            FIOffset << "]\n");
+      MFI->setObjectOffset(Entry.first, FIOffset);
+    }
+    // Allocate the local block
+    Offset += MFI->getLocalFrameSize();
+
+    MaxAlign = std::max(Align, MaxAlign);
+  }
+
+  // No stack protector
+
+  // Then assign frame offsets to stack objects that are not used to spill
+  // callee saved registers.
+  for (unsigned i = 0, e = MFI->getObjectIndexEnd(); i != e; ++i) {
+    if (MFI->isObjectPreAllocated(i) &&
+        MFI->getUseLocalStackAllocationBlock())
+      continue;
+    if (MFI->isDeadObjectIndex(i))
+      continue;
+
+    AdjustStackOffset(MFI, i, StackGrowsDown, Offset, MaxAlign);
+  }
+
+  // No scavenger
+
+  if (!TFI.targetHandlesStackFrameRounding()) {
+    // If we have reserved argument space for call sites in the function
+    // immediately on entry to the current function, count it as part of the
+    // overall stack size.
+    if (MFI->adjustsStack() && TFI.hasReservedCallFrame(Fn))
+      Offset += MFI->getMaxCallFrameSize();
+
+    // Round up the size to a multiple of the alignment.  If the function has
+    // any calls or alloca's, align to the target's StackAlignment value to
+    // ensure that the callee's frame or the alloca data is suitably aligned;
+    // otherwise, for leaf functions, align to the TransientStackAlignment
+    // value.
+    unsigned StackAlign;
+    if (MFI->adjustsStack() || MFI->hasVarSizedObjects() ||
+        (RegInfo->needsStackRealignment(Fn) && MFI->getObjectIndexEnd() != 0))
+      StackAlign = TFI.getStackAlignment();
+    else
+      StackAlign = TFI.getTransientStackAlignment();
+
+    // If the frame pointer is eliminated, all frame offsets will be relative to
+    // SP not FP. Align to MaxAlign so this works.
+    StackAlign = std::max(StackAlign, MaxAlign);
+    unsigned AlignMask = StackAlign - 1;
+    Offset = (Offset + AlignMask) & ~uint64_t(AlignMask);
+  }
+
+  // Update frame info to pretend that this is part of the stack...
+  int64_t StackSize = Offset - LocalAreaOffset;
+  MFI->setStackSize(StackSize);
+}