1 files changed, 60 insertions, 20 deletions

diff --git a/contrib/llvm/lib/Target/ARM/ARMFrameLowering.cpp b/contrib/llvm/lib/Target/ARM/ARMFrameLowering.cpp
index e2e95d47b37b..381b404519e2 100644
--- a/contrib/llvm/lib/Target/ARM/ARMFrameLowering.cpp
+++ b/contrib/llvm/lib/Target/ARM/ARMFrameLowering.cpp
@@ -268,14 +268,14 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
       // bic r4, r4, MaxAlign
       // mov sp, r4
       // FIXME: It will be better just to find spare register here.
-      BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2tgpr), ARM::R4)
-        .addReg(ARM::SP, RegState::Kill);
+      AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), ARM::R4)
+        .addReg(ARM::SP, RegState::Kill));
       AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl,
                                           TII.get(ARM::t2BICri), ARM::R4)
                                   .addReg(ARM::R4, RegState::Kill)
                                   .addImm(MaxAlign-1)));
-      BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVtgpr2gpr), ARM::SP)
-        .addReg(ARM::R4, RegState::Kill);
+      AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), ARM::SP)
+        .addReg(ARM::R4, RegState::Kill));
     }
 
     AFI->setShouldRestoreSPFromFP(true);
@@ -293,9 +293,9 @@ void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
         .addReg(ARM::SP)
         .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
     else
-      BuildMI(MBB, MBBI, dl,
-              TII.get(ARM::tMOVgpr2gpr), RegInfo->getBaseRegister())
-        .addReg(ARM::SP);
+      AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr),
+                             RegInfo->getBaseRegister())
+        .addReg(ARM::SP));
   }
 
   // If the frame has variable sized objects then the epilogue must restore
@@ -364,8 +364,9 @@ void ARMFrameLowering::emitEpilogue(MachineFunction &MF,
                  "No scratch register to restore SP from FP!");
           emitT2RegPlusImmediate(MBB, MBBI, dl, ARM::R4, FramePtr, -NumBytes,
                                  ARMCC::AL, 0, TII);
-          BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr), ARM::SP)
-            .addReg(ARM::R4);
+          AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr),
+                                 ARM::SP)
+            .addReg(ARM::R4));
         }
       } else {
         // Thumb2 or ARM.
@@ -373,8 +374,9 @@ void ARMFrameLowering::emitEpilogue(MachineFunction &MF,
           BuildMI(MBB, MBBI, dl, TII.get(ARM::MOVr), ARM::SP)
             .addReg(FramePtr).addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
         else
-          BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr), ARM::SP)
-            .addReg(FramePtr);
+          AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr),
+                                 ARM::SP)
+            .addReg(FramePtr));
       }
     } else if (NumBytes)
       emitSPUpdate(isARM, MBB, MBBI, dl, TII, NumBytes);
@@ -427,6 +429,7 @@ void ARMFrameLowering::emitEpilogue(MachineFunction &MF,
 
     // Delete the pseudo instruction TCRETURN.
     MBB.erase(MBBI);
+    MBBI = NewMI;
   }
 
   if (VARegSaveSize)
@@ -736,20 +739,52 @@ static unsigned GetFunctionSizeInBytes(const MachineFunction &MF,
 /// estimateStackSize - Estimate and return the size of the frame.
 /// FIXME: Make generic?
 static unsigned estimateStackSize(MachineFunction &MF) {
-  const MachineFrameInfo *FFI = MF.getFrameInfo();
+  const MachineFrameInfo *MFI = MF.getFrameInfo();
+  const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering();
+  const TargetRegisterInfo *RegInfo = MF.getTarget().getRegisterInfo();
+  unsigned MaxAlign = MFI->getMaxAlignment();
   int Offset = 0;
-  for (int i = FFI->getObjectIndexBegin(); i != 0; ++i) {
-    int FixedOff = -FFI->getObjectOffset(i);
+
+  // This code is very, very similar to PEI::calculateFrameObjectOffsets().
+  // It really should be refactored to share code. Until then, changes
+  // should keep in mind that there's tight coupling between the two.
+
+  for (int i = MFI->getObjectIndexBegin(); i != 0; ++i) {
+    int FixedOff = -MFI->getObjectOffset(i);
     if (FixedOff > Offset) Offset = FixedOff;
   }
-  for (unsigned i = 0, e = FFI->getObjectIndexEnd(); i != e; ++i) {
-    if (FFI->isDeadObjectIndex(i))
+  for (unsigned i = 0, e = MFI->getObjectIndexEnd(); i != e; ++i) {
+    if (MFI->isDeadObjectIndex(i))
       continue;
-    Offset += FFI->getObjectSize(i);
-    unsigned Align = FFI->getObjectAlignment(i);
+    Offset += MFI->getObjectSize(i);
+    unsigned Align = MFI->getObjectAlignment(i);
     // Adjust to alignment boundary
     Offset = (Offset+Align-1)/Align*Align;
+
+    MaxAlign = std::max(Align, MaxAlign);
   }
+
+  if (MFI->adjustsStack() && TFI->hasReservedCallFrame(MF))
+    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(MF) && 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);
+
   return (unsigned)Offset;
 }
 
@@ -841,9 +876,14 @@ ARMFrameLowering::processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
     if (AFI->getVarArgsRegSaveSize() > 0)
       MF.getRegInfo().setPhysRegUsed(ARM::LR);
 
-    // Spill R4 if Thumb1 epilogue has to restore SP from FP since 
+    // Spill R4 if Thumb1 epilogue has to restore SP from FP. We don't know
+    // for sure what the stack size will be, but for this, an estimate is good
+    // enough. If there anything changes it, it'll be a spill, which implies
+    // we've used all the registers and so R4 is already used, so not marking
+    // it here will be OK.
     // FIXME: It will be better just to find spare register here.
-    if (MFI->hasVarSizedObjects())
+    unsigned StackSize = estimateStackSize(MF);
+    if (MFI->hasVarSizedObjects() || StackSize > 508)
       MF.getRegInfo().setPhysRegUsed(ARM::R4);
   }