Add with value 0 so that structure zero initialization can
indicate that the field is not present.

Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 tcg/tcg-opc.h | 2 ++
 tcg/tcg.c     | 3 +++
 2 files changed, 5 insertions(+)

diff --git a/tcg/tcg-opc.h b/tcg/tcg-opc.h
index edfdbf8798..b84cd584fb 100644
--- a/tcg/tcg-opc.h
+++ b/tcg/tcg-opc.h
@@ -26,6 +26,8 @@
  * DEF(name, oargs, iargs, cargs, flags)
  */
 
+DEF(invalid, 0, 0, 0, TCG_OPF_NOT_PRESENT)
+
 /* predefined ops */
 DEF(discard, 1, 0, 0, TCG_OPF_NOT_PRESENT)
 DEF(set_label, 0, 0, 1, TCG_OPF_BB_END | TCG_OPF_NOT_PRESENT)
diff --git a/tcg/tcg.c b/tcg/tcg.c
index 9aea00d9b4..8fca202bec 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -754,6 +754,9 @@ int tcg_check_temp_count(void)
 bool tcg_op_supported(TCGOpcode op)
 {
     switch (op) {
+    case INDEX_op_invalid:
+        return false;
+
     case INDEX_op_discard:
     case INDEX_op_set_label:
     case INDEX_op_call:
-- 
2.13.5