The "system instructions" and "system register move" subcategories
of "branches, exception generating and system instructions" for A64
only apply if bits [23:22] are zero; other values are currently
unallocated. Correctly UNDEF these unallocated encodings.
Reported-by: Laurent Desnogues <laurent.desnog...@gmail.com>
Signed-off-by: Peter Maydell <peter.mayd...@linaro.org>
---
target/arm/translate-a64.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 4d28a27c3bd..e6df303e321 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -2144,7 +2144,11 @@ static void disas_b_exc_sys(DisasContext *s, uint32_t
insn)
break;
case 0x6a: /* Exception generation / System */
if (insn & (1 << 24)) {
- disas_system(s, insn);
+ if (extract32(insn, 22, 2) == 0) {
+ disas_system(s, insn);
+ } else {
+ unallocated_encoding(s);
+ }
} else {
disas_exc(s, insn);
}
--
2.20.1
