Clean up ARM tail calls a bit. They're pseudo-instructions for normal branches.
Also more cleanly separate the ARM vs. Thumb functionality. Previously, the
encoding would be incorrect for some Thumb instructions (the indirect calls).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127637 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMFrameLowering.cpp b/lib/Target/ARM/ARMFrameLowering.cpp
index 4ade29c..c99259d 100644
--- a/lib/Target/ARM/ARMFrameLowering.cpp
+++ b/lib/Target/ARM/ARMFrameLowering.cpp
@@ -400,8 +400,8 @@
     // Jump to label or value in register.
     if (RetOpcode == ARM::TCRETURNdi || RetOpcode == ARM::TCRETURNdiND) {
       unsigned TCOpcode = (RetOpcode == ARM::TCRETURNdi)
-        ? (STI.isThumb() ? ARM::TAILJMPdt : ARM::TAILJMPd)
-        : (STI.isThumb() ? ARM::TAILJMPdNDt : ARM::TAILJMPdND);
+        ? (STI.isThumb() ? ARM::tTAILJMPd : ARM::TAILJMPd)
+        : (STI.isThumb() ? ARM::tTAILJMPdND : ARM::TAILJMPdND);
       MachineInstrBuilder MIB = BuildMI(MBB, MBBI, dl, TII.get(TCOpcode));
       if (JumpTarget.isGlobal())
         MIB.addGlobalAddress(JumpTarget.getGlobal(), JumpTarget.getOffset(),
@@ -412,10 +412,12 @@
                               JumpTarget.getTargetFlags());
       }
     } else if (RetOpcode == ARM::TCRETURNri) {
-      BuildMI(MBB, MBBI, dl, TII.get(ARM::TAILJMPr)).
+      BuildMI(MBB, MBBI, dl,
+              TII.get(STI.isThumb() ? ARM::tTAILJMPr : ARM::TAILJMPr)).
         addReg(JumpTarget.getReg(), RegState::Kill);
     } else if (RetOpcode == ARM::TCRETURNriND) {
-      BuildMI(MBB, MBBI, dl, TII.get(ARM::TAILJMPrND)).
+      BuildMI(MBB, MBBI, dl,
+              TII.get(STI.isThumb() ? ARM::tTAILJMPrND : ARM::TAILJMPrND)).
         addReg(JumpTarget.getReg(), RegState::Kill);
     }