target/arm/translate-a64: Don't underdecode SIMD ld/st multiple

In the AdvSIMD load/store multiple structures encodings,
the non-post-indexed case should have zeroes in [20:16]
(which is the Rm field for the post-indexed case).
Correctly UNDEF the currently unallocated encodings which
have non-zeroes in those bits.

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: 20190125182626.9221-4-peter.maydell@linaro.org
This commit is contained in:
Peter Maydell 2019-02-01 14:55:44 +00:00
parent a80c425654
commit e1f220811d

View File

@ -3249,6 +3249,7 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
{
int rt = extract32(insn, 0, 5);
int rn = extract32(insn, 5, 5);
int rm = extract32(insn, 16, 5);
int size = extract32(insn, 10, 2);
int opcode = extract32(insn, 12, 4);
bool is_store = !extract32(insn, 22, 1);
@ -3268,6 +3269,11 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
return;
}
if (!is_postidx && rm != 0) {
unallocated_encoding(s);
return;
}
/* From the shared decode logic */
switch (opcode) {
case 0x0:
@ -3367,7 +3373,6 @@ static void disas_ldst_multiple_struct(DisasContext *s, uint32_t insn)
}
if (is_postidx) {
int rm = extract32(insn, 16, 5);
if (rm == 31) {
tcg_gen_mov_i64(tcg_rn, tcg_addr);
} else {