X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FARM%2FThumb1FrameLowering.h;h=812f9830824de99a61909be5f6d357a7fc6cf485;hb=5a1af3657c51ec2b5d2a71b3dd877acc4a4d60aa;hp=bcfc5165fad0f0129b5db1d0e0389365f6a100d3;hpb=dac4b9267bc4e61de9237c622cd5b145768302fc;p=oota-llvm.git

diff --git a/lib/Target/ARM/Thumb1FrameLowering.h b/lib/Target/ARM/Thumb1FrameLowering.h
index bcfc5165fad..812f9830824 100644
--- a/lib/Target/ARM/Thumb1FrameLowering.h
+++ b/lib/Target/ARM/Thumb1FrameLowering.h
@@ -11,40 +11,76 @@
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef __THUMB_FRAMEINFO_H_
-#define __THUMB_FRAMEINFO_H_
+#ifndef LLVM_LIB_TARGET_ARM_THUMB1FRAMELOWERING_H
+#define LLVM_LIB_TARGET_ARM_THUMB1FRAMELOWERING_H
 
-#include "ARM.h"
 #include "ARMFrameLowering.h"
-#include "ARMSubtarget.h"
 #include "Thumb1InstrInfo.h"
-#include "Thumb1RegisterInfo.h"
+#include "ThumbRegisterInfo.h"
 #include "llvm/Target/TargetFrameLowering.h"
 
 namespace llvm {
-  class ARMSubtarget;
 
 class Thumb1FrameLowering : public ARMFrameLowering {
 public:
-  explicit Thumb1FrameLowering(const ARMSubtarget &sti)
-    : ARMFrameLowering(sti) {
-  }
+  explicit Thumb1FrameLowering(const ARMSubtarget &sti);
 
   /// emitProlog/emitEpilog - These methods insert prolog and epilog code into
   /// the function.
-  void emitPrologue(MachineFunction &MF) const;
-  void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const;
+  void emitPrologue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
+  void emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const override;
 
   bool spillCalleeSavedRegisters(MachineBasicBlock &MBB,
                                  MachineBasicBlock::iterator MI,
                                  const std::vector<CalleeSavedInfo> &CSI,
-                                 const TargetRegisterInfo *TRI) const;
+                                 const TargetRegisterInfo *TRI) const override;
   bool restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
-                                   MachineBasicBlock::iterator MI,
-                                   const std::vector<CalleeSavedInfo> &CSI,
-                                   const TargetRegisterInfo *TRI) const;
+                                  MachineBasicBlock::iterator MI,
+                                  const std::vector<CalleeSavedInfo> &CSI,
+                                  const TargetRegisterInfo *TRI) const override;
 
-  bool hasReservedCallFrame(const MachineFunction &MF) const;
+  bool hasReservedCallFrame(const MachineFunction &MF) const override;
+
+  void
+  eliminateCallFramePseudoInstr(MachineFunction &MF,
+                                MachineBasicBlock &MBB,
+                                MachineBasicBlock::iterator MI) const override;
+
+  /// Check whether or not the given \p MBB can be used as a epilogue
+  /// for the target.
+  /// The epilogue will be inserted before the first terminator of that block.
+  /// This method is used by the shrink-wrapping pass to decide if
+  /// \p MBB will be correctly handled by the target.
+  bool canUseAsEpilogue(const MachineBasicBlock &MBB) const override;
+
+private:
+  /// Check if the frame lowering of \p MF needs a special fixup
+  /// code sequence for the epilogue.
+  /// Unlike T2 and ARM mode, the T1 pop instruction cannot restore
+  /// to LR, and we can't pop the value directly to the PC when
+  /// we need to update the SP after popping the value. So instead
+  /// we have to emit:
+  ///   POP {r3}
+  ///   ADD sp, #offset
+  ///   BX r3
+  /// If this would clobber a return value, then generate this sequence instead:
+  ///   MOV ip, r3
+  ///   POP {r3}
+  ///   ADD sp, #offset
+  ///   MOV lr, r3
+  ///   MOV r3, ip
+  ///   BX lr
+  bool needPopSpecialFixUp(const MachineFunction &MF) const;
+
+  /// Emit the special fixup code sequence for the epilogue.
+  /// \see needPopSpecialFixUp for more details.
+  /// \p DoIt, tells this method whether or not to actually insert
+  /// the code sequence in \p MBB. I.e., when \p DoIt is false,
+  /// \p MBB is left untouched.
+  /// \returns For \p DoIt == true: True when the emission succeeded
+  /// false otherwise. For \p DoIt == false: True when the emission
+  /// would have been possible, false otherwise.
+  bool emitPopSpecialFixUp(MachineBasicBlock &MBB, bool DoIt) const;
 };
 
 } // End llvm namespace