Thumb disassembler was erroneously rejecting "blx sp" instruction.

rdar://problem/9267838


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129320 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/ARMDecoderEmitter.cpp b/utils/TableGen/ARMDecoderEmitter.cpp
index e48ac1e..07ff213 100644
--- a/utils/TableGen/ARMDecoderEmitter.cpp
+++ b/utils/TableGen/ARMDecoderEmitter.cpp
@@ -1624,6 +1624,10 @@
     if (Name == "tBL" || Name == "tBLXi" || Name == "tBLXr")
       return false;
 
+    // A8.6.25 BX.  Use the generic tBX_Rm, ignore tBX_RET and tBX_RET_vararg.
+    if (Name == "tBX_RET" || Name == "tBX_RET_vararg")
+      return false;
+
     // Ignore the TPsoft (TLS) instructions, which conflict with tBLr9.
     if (Name == "tTPsoft" || Name == "t2TPsoft")
       return false;