Fix coordination for using R4 in Thumb1 as a scratch for SP restore.
The logic for reserving R4 for use as a scratch needs to match that for
actually using it. Also, it's not necessary for immediate <=508, so adjust
the value checked.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132934 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/Thumb1FrameLowering.cpp b/lib/Target/ARM/Thumb1FrameLowering.cpp
index dee3d27..e56d481 100644
--- a/lib/Target/ARM/Thumb1FrameLowering.cpp
+++ b/lib/Target/ARM/Thumb1FrameLowering.cpp
@@ -136,8 +136,8 @@
BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
.addFrameIndex(FramePtrSpillFI).addImm(0)
.setMIFlags(MachineInstr::FrameSetup);
- if (NumBytes > 7)
- // If offset is > 7 then sp cannot be adjusted in a single instruction,
+ if (NumBytes > 508)
+ // If offset is > 508 then sp cannot be adjusted in a single instruction,
// try restoring from fp instead.
AFI->setShouldRestoreSPFromFP(true);
}