[llvm-commits] [llvm] r116729 - /llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp

[Jim Grosbach]

Author: grosbach
Date: Mon Oct 18 13:39:46 2010
New Revision: 116729

URL: http://llvm.org/viewvc/llvm-project?rev=116729&view=rev
Log:
For Thumb2, try to use frame pointer references for stack slots even when a
base register is available. rdar://8525298

Modified:
    llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp

Modified: llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp?rev=116729&r1=116728&r2=116729&view=diff
==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMBaseRegisterInfo.cpp Mon Oct 18 13:39:46 2010
@@ -953,8 +953,16 @@
       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.