Add support for emitting ARM file attributes.

[oota-llvm.git] / lib / Target / ARM / ARMBaseRegisterInfo.cpp

diff --git a/lib/Target/ARM/ARMBaseRegisterInfo.cpp b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
index acb61b218ac7b000f946c4b09b7666f6d0c73ec0..7fb4616a9b678c471937b7e3c8f18633b4ecce97 100644 (file)
--- a/lib/Target/ARM/ARMBaseRegisterInfo.cpp
+++ b/lib/Target/ARM/ARMBaseRegisterInfo.cpp
@@ -953,8 +953,16 @@ ARMBaseRegisterInfo::ResolveFrameIndexReference(const MachineFunction &MF,
       return FPOffset;
     } else if (MFI->hasVarSizedObjects()) {
       assert(hasBasePointer(MF) && "missing base pointer!");
-      // Use the base register since we have it.
-      FrameReg = BasePtr;
+      // Try to use the frame pointer if we can, else use the base pointer
+      // since it's available. This is handy for the emergency spill slot, in
+      // particular.
+      if (AFI->isThumb2Function()) {
+        if (FPOffset >= -255 && FPOffset < 0) {
+          FrameReg = getFrameRegister(MF);
+          return FPOffset;
+        }
+      } else
+        FrameReg = BasePtr;
     } else if (AFI->isThumb2Function()) {
       // In Thumb2 mode, the negative offset is very limited. Try to avoid
       // out of range references.
@@ -1664,7 +1672,7 @@ emitPrologue(MachineFunction &MF) const {
 
   // Determine the sizes of each callee-save spill areas and record which frame
   // belongs to which callee-save spill areas.
-  unsigned GPRCSSize = 0/*, GPRCS2Size = 0*/, DPRCSSize = 0;
+  unsigned GPRCSSize = 0, DPRCSSize = 0;
   int FramePtrSpillFI = 0;
 
   // Allocate the vararg register save area. This is not counted in NumBytes.