target/arm/translate-a64: Fix FCMLA decoding error

The FCMLA (by element) instruction exists in the
"vector x indexed element" encoding group, but not in
the "scalar x indexed element" group. Correctly UNDEF
the unallocated encodings.

Reported-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Laurent Desnogues <laurent.desnogues@gmail.com>
Message-id: 20190129140411.682-2-peter.maydell@linaro.org

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 07fa05239351e1efa06e602583641e1831cb874a..d46ea9f64e7d0d6440a1a930f4eb3abce47c8256 100644 (file)
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -12650,7 +12650,7 @@ static void disas_simd_indexed(DisasContext *s, uint32_t insn)
     case 0x13: /* FCMLA #90 */
     case 0x15: /* FCMLA #180 */
     case 0x17: /* FCMLA #270 */
-        if (!dc_isar_feature(aa64_fcma, s)) {
+        if (is_scalar || !dc_isar_feature(aa64_fcma, s)) {
             unallocated_encoding(s);
             return;
         }