ctxt->modrm_seg = VCPU_SREG_DS;
if (ctxt->modrm_mod == 3) {
+ int highbyte_regs = ctxt->rex_prefix == 0;
+
op->type = OP_REG;
op->bytes = (ctxt->d & ByteOp) ? 1 : ctxt->op_bytes;
- op->addr.reg = decode_register(ctxt, ctxt->modrm_rm, ctxt->d & ByteOp);
+ op->addr.reg = decode_register(ctxt, ctxt->modrm_rm,
+ highbyte_regs && (ctxt->d & ByteOp));
if (ctxt->d & Sse) {
op->type = OP_XMM;
op->bytes = 16;
DI(ImplicitOps | Priv, invd), DI(ImplicitOps | Priv, wbinvd), N, N,
N, D(ImplicitOps | ModRM), N, N,
/* 0x10 - 0x1F */
- N, N, N, N, N, N, N, N, D(ImplicitOps | ModRM), N, N, N, N, N, N, N,
+ N, N, N, N, N, N, N, N,
+ D(ImplicitOps | ModRM), N, N, N, N, N, N, D(ImplicitOps | ModRM),
/* 0x20 - 0x2F */
DIP(ModRM | DstMem | Priv | Op3264, cr_read, check_cr_read),
DIP(ModRM | DstMem | Priv | Op3264, dr_read, check_dr_read),
case OpMem8:
ctxt->memop.bytes = 1;
if (ctxt->memop.type == OP_REG) {
- ctxt->memop.addr.reg = decode_register(ctxt, ctxt->modrm_rm, 1);
+ int highbyte_regs = ctxt->rex_prefix == 0;
+
+ ctxt->memop.addr.reg = decode_register(ctxt, ctxt->modrm_rm,
+ highbyte_regs);
fetch_register_operand(&ctxt->memop);
}
goto mem_common;
case 0x08: /* invd */
case 0x0d: /* GrpP (prefetch) */
case 0x18: /* Grp16 (prefetch/nop) */
+ case 0x1f: /* nop */
break;
case 0x20: /* mov cr, reg */
ctxt->dst.val = ops->get_cr(ctxt, ctxt->modrm_reg);