Commit e14f0eb1 authored by Peter Maydell's avatar Peter Maydell
Browse files

target-arm/translate-a64.c: Correct unallocated checks for ldst_excl 



The checks for the unallocated encodings in the ldst_excl group
(exclusives and load-acquire/store-release) were not correct. This
error meant that in turn we ended up with code attempting to handle
the non-existent case of "non-exclusive load-acquire/store-release
pair". Delete that broken and now unreachable code.

Reported-by: default avatarLaurent Desnogues <laurent.desnogues@gmail.com>
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarLaurent Desnogues <laurent.desnogues@gmail.com>
Reviewed-by: default avatarEdgar E. Iglesias <edgar.iglesias@xilinx.com>
Reviewed-by: default avatarSergey Fedorov <serge.fdrv@gmail.com>
parent 6109769a

target-arm/translate-a64.c

+2 −13
Original line number Diff line number Diff line
@@ -1816,9 +1816,6 @@ static void gen_store_exclusive(DisasContext *s, int rd, int rt, int rt2, 
 *  o2: 0 -> exclusive, 1 -> not

 *  o1: 0 -> single register, 1 -> register pair

 *  o0: 1 -> load-acquire/store-release, 0 -> not

 *

 *  o0 == 0 AND o2 == 1 is un-allocated

 *  o1 == 1 is un-allocated except for 32 and 64 bit sizes

 */

static void disas_ldst_excl(DisasContext *s, uint32_t insn)

{
@@ -1833,7 +1830,8 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn) 
    int size = extract32(insn, 30, 2);

    TCGv_i64 tcg_addr;



    if ((!is_excl && !is_lasr) ||

    if ((!is_excl && !is_pair && !is_lasr) ||

        (!is_excl && is_pair) ||

        (is_pair && size < 2)) {

        unallocated_encoding(s);

        return;
@@ -1862,15 +1860,6 @@ static void disas_ldst_excl(DisasContext *s, uint32_t insn) 
        } else {

            do_gpr_ld(s, tcg_rt, tcg_addr, size, false, false);

        }

        if (is_pair) {

            TCGv_i64 tcg_rt2 = cpu_reg(s, rt);

            tcg_gen_addi_i64(tcg_addr, tcg_addr, 1 << size);

            if (is_store) {

                do_gpr_st(s, tcg_rt2, tcg_addr, size);

            } else {

                do_gpr_ld(s, tcg_rt2, tcg_addr, size, false, false);

            }

        }

    }

}