1 files changed, 15 insertions, 34 deletions

diff --git a/lib/Target/ARM/Thumb1FrameLowering.cpp b/lib/Target/ARM/Thumb1FrameLowering.cpp
index ad1edc8..edd73c2 100644
--- a/lib/Target/ARM/Thumb1FrameLowering.cpp
+++ b/lib/Target/ARM/Thumb1FrameLowering.cpp
@@ -1,4 +1,4 @@
-//======- Thumb1FrameLowering.cpp - Thumb1 Frame Information ---*- C++ -*-====//
+//===-- Thumb1FrameLowering.cpp - Thumb1 Frame Information ----------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
@@ -12,7 +12,6 @@
 //===----------------------------------------------------------------------===//
 
 #include "Thumb1FrameLowering.h"
-#include "ARMBaseInstrInfo.h"
 #include "ARMMachineFunctionInfo.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
@@ -101,7 +100,7 @@ void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
     case ARM::R11:
       if (Reg == FramePtr)
         FramePtrSpillFI = FI;
-      if (STI.isTargetDarwin()) {
+      if (STI.isTargetIOS()) {
         AFI->addGPRCalleeSavedArea2Frame(FI);
         GPRCS2Size += 4;
       } else {
@@ -155,32 +154,10 @@ void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
   AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
   AFI->setDPRCalleeSavedAreaSize(DPRCSSize);
 
-  // If we need dynamic stack realignment, do it here. Be paranoid and make
-  // sure if we also have VLAs, we have a base pointer for frame access.
-  if (RegInfo->needsStackRealignment(MF)) {
-    // We cannot use sp as source/dest register here, thus we're emitting the
-    // following sequence:
-    // mov r4, sp
-    // lsrs r4, r4, Log2MaxAlign
-    // lsls r4, r4, Log2MaxAlign
-    // mov sp, r4
-    unsigned MaxAlign = MFI->getMaxAlignment();
-    unsigned Log2MaxAlign = Log2_32(MaxAlign);
-    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), ARM::R4)
-                   .addReg(ARM::SP, RegState::Kill));
-    AddDefaultPred(AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TII.get(ARM::tLSRri),
-                                          ARM::R4))
-                   .addReg(ARM::R4, RegState::Kill)
-                   .addImm(Log2MaxAlign));
-    AddDefaultPred(AddDefaultT1CC(BuildMI(MBB, MBBI, dl, TII.get(ARM::tLSLri),
-                                          ARM::R4))
-                   .addReg(ARM::R4, RegState::Kill)
-                   .addImm(Log2MaxAlign));
-    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), ARM::SP)
-                   .addReg(ARM::R4, RegState::Kill));
-
-    AFI->setShouldRestoreSPFromFP(true);    
-  }
+  // Thumb1 does not currently support dynamic stack realignment.  Report a
+  // fatal error rather then silently generate bad code.
+  if (RegInfo->needsStackRealignment(MF))
+      report_fatal_error("Dynamic stack realignment not supported for thumb1.");
 
   // If we need a base pointer, set it up here. It's whatever the value
   // of the stack pointer is at this point. Any variable size objects
@@ -197,14 +174,14 @@ void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
     AFI->setShouldRestoreSPFromFP(true);
 }
 
-static bool isCalleeSavedRegister(unsigned Reg, const unsigned *CSRegs) {
+static bool isCalleeSavedRegister(unsigned Reg, const uint16_t *CSRegs) {
   for (unsigned i = 0; CSRegs[i]; ++i)
     if (Reg == CSRegs[i])
       return true;
   return false;
 }
 
-static bool isCSRestore(MachineInstr *MI, const unsigned *CSRegs) {
+static bool isCSRestore(MachineInstr *MI, const uint16_t *CSRegs) {
   if (MI->getOpcode() == ARM::tLDRspi &&
       MI->getOperand(1).isFI() &&
       isCalleeSavedRegister(MI->getOperand(0).getReg(), CSRegs))
@@ -236,7 +213,7 @@ void Thumb1FrameLowering::emitEpilogue(MachineFunction &MF,
 
   unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
   int NumBytes = (int)MFI->getStackSize();
-  const unsigned *CSRegs = RegInfo->getCalleeSavedRegs();
+  const uint16_t *CSRegs = RegInfo->getCalleeSavedRegs();
   unsigned FramePtr = RegInfo->getFrameRegister(MF);
 
   if (!AFI->hasStackFrame()) {
@@ -300,8 +277,11 @@ void Thumb1FrameLowering::emitEpilogue(MachineFunction &MF,
 
     emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, VARegSaveSize);
 
-    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tBX_RET_vararg))
-      .addReg(ARM::R3, RegState::Kill));
+    MachineInstrBuilder MIB =
+      BuildMI(MBB, MBBI, dl, TII.get(ARM::tBX_RET_vararg))
+      .addReg(ARM::R3, RegState::Kill);
+    AddDefaultPred(MIB);
+    MIB->copyImplicitOps(&*MBBI);
     // erase the old tBX_RET instruction
     MBB.erase(MBBI);
   }
@@ -372,6 +352,7 @@ restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
         continue;
       Reg = ARM::PC;
       (*MIB).setDesc(TII.get(ARM::tPOP_RET));
+      MIB->copyImplicitOps(&*MI);
       MI = MBB.erase(MI);
     }
     MIB.addReg(Reg, getDefRegState(true));