aarch64: Restrict range of PRFM opcodes

In the register-index forms of PRFM, the unallocated prefetch opcodes
24-31 have been reused for the encoding of the new RPRFM instruction.
The PRFM opcode space is now capped at 23 for these forms.  The other
forms of PRFM are unaffected.

1 files changed, 9 insertions, 0 deletions

diff --git a/opcodes/aarch64-opc.c b/opcodes/aarch64-opc.c
index e271b0d..a0e6240 100644
--- a/opcodes/aarch64-opc.c
+++ b/opcodes/aarch64-opc.c
@@ -2599,6 +2599,15 @@ operand_general_constraint_met_p (const aarch64_opnd_info *opnds, int idx,
 	      return 0;
 	    }
 	  break;
+	case AARCH64_OPND_PRFOP:
+	  if (opcode->iclass == ldst_regoff && opnd->prfop->value >= 24)
+	    {
+	      set_other_error (mismatch_detail, idx,
+			       _("the register-index form of PRFM does"
+				 " not accept opcodes in the range 24-31"));
+	      return 0;
+	    }
+	  break;
 	default:
 	  break;
 	}