The Thumb2 RFE instructions need to have their second halfword fully specified.

In addition, the base register is not rGPR, but GPR with th exception that:

    if n == 15 then UNPREDICTABLE

rdar://problem/9273836

llvm-svn: 129391

1 files changed, 6 insertions, 2 deletions

diff --git a/llvm/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h b/llvm/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
index 3d2d1ab947f..e29d84604ec 100644
--- a/llvm/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
+++ b/llvm/lib/Target/ARM/Disassembler/ThumbDisassemblerCore.h
@@ -1142,8 +1142,12 @@ static bool DisassembleThumb2SRS(MCInst &MI, unsigned Opcode, uint32_t insn,
 // t2RFE[IA|DB]W/t2RFE[IA|DB]: Rn
 static bool DisassembleThumb2RFE(MCInst &MI, unsigned Opcode, uint32_t insn,
     unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
-  MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
-                                                     decodeRn(insn))));
+  unsigned Rn = decodeRn(insn);
+  if (Rn == 15) {
+    DEBUG(errs() << "if n == 15 then UNPREDICTABLE\n");
+    return false;
+  }
+  MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B,ARM::GPRRegClassID,Rn)));
   NumOpsAdded = 1;
   return true;
 }