In the "add/subtract (extended register)" encoding group, the "opt"
field in bits [23:22] must be zero. Correctly UNDEF the unallocated
encodings where this field is not zero.
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: 20190125182626.9221-6-peter.maydell@linaro.org
---
target/arm/translate-a64.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 2cade64ed25..94907f0ae97 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -4201,6 +4201,7 @@ static void disas_add_sub_ext_reg(DisasContext *s, uint32_t insn)
int imm3 = extract32(insn, 10, 3);
int option = extract32(insn, 13, 3);
int rm = extract32(insn, 16, 5);
+ int opt = extract32(insn, 22, 2);
bool setflags = extract32(insn, 29, 1);
bool sub_op = extract32(insn, 30, 1);
bool sf = extract32(insn, 31, 1);
@@ -4209,7 +4210,7 @@ static void disas_add_sub_ext_reg(DisasContext *s, uint32_t insn)
TCGv_i64 tcg_rd;
TCGv_i64 tcg_result;
- if (imm3 > 4) {
+ if (imm3 > 4 || opt != 0) {
unallocated_encoding(s);
return;
}
--
2.20.1