Hi Alex,
On 09/27/13 02:48, Alexander Graf wrote:
> This adds handling for the b and bl instructions.
>
> Signed-off-by: Alexander Graf <[email protected]>
> ---
> target-arm/translate-a64.c | 61
> ++++++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 61 insertions(+)
>
> diff --git a/target-arm/translate-a64.c b/target-arm/translate-a64.c
> index 73ccade..267fd4d 100644
> --- a/target-arm/translate-a64.c
> +++ b/target-arm/translate-a64.c
> @@ -133,6 +133,58 @@ static void real_unallocated_encoding(DisasContext *s)
> real_unallocated_encoding(s); \
> } while (0)
>
> +static int get_bits(uint32_t inst, int start, int len)
> +{
> + return (inst >> start) & ((1 << len) - 1);
> +}
> +
do you think it makes sense to reuse extract32 from bitops here?
> +static int get_sbits(uint32_t inst, int start, int len)
> +{
> + int r = get_bits(inst, start, len);
> + if (r & (1 << (len - 1))) {
> + /* Extend the MSB 1 to the higher bits */
> + r |= -1 & ~((1ULL << len) - 1);
> + }
> + return r;
> +}
> +
sextract32?
> +static TCGv_i64 cpu_reg(int reg)
> +{
> + if (reg == 31) {
> + /* XXX leaks temps */
> + return tcg_const_i64(0);
...
> + } else {
> + return cpu_X[reg];
> + }
> +}
> +
> +static inline void gen_goto_tb(DisasContext *s, int n, uint64_t dest)
> +{
> + TranslationBlock *tb;
> +
> + tb = s->tb;
> + if ((tb->pc & TARGET_PAGE_MASK) == (dest & TARGET_PAGE_MASK)) {
> + tcg_gen_goto_tb(n);
> + gen_a64_set_pc_im(dest);
> + tcg_gen_exit_tb((tcg_target_long)tb + n);
> + } else {
> + gen_a64_set_pc_im(dest);
> + tcg_gen_exit_tb(0);
> + }
> +}
> +
> +static void handle_b(DisasContext *s, uint32_t insn)
> +{
> + uint64_t addr = s->pc - 4 + (get_sbits(insn, 0, 26) << 2);
> +
> + if (get_bits(insn, 31, 1)) {
> + /* BL */
> + tcg_gen_movi_i64(cpu_reg(30), s->pc);
> + }
> + gen_goto_tb(s, 0, addr);
> + s->is_jmp = DISAS_TB_JUMP;
> +}
> +
> void disas_a64_insn(CPUARMState *env, DisasContext *s)
> {
> uint32_t insn;
> @@ -141,12 +193,21 @@ void disas_a64_insn(CPUARMState *env, DisasContext *s)
> s->insn = insn;
> s->pc += 4;
>
> + /* One-off branch instruction layout */
> + switch (insn >> 26) {
> + case 0x25:
> + case 0x5:
> + handle_b(s, insn);
> + goto insn_done;
> + }
> +
> switch ((insn >> 24) & 0x1f) {
> default:
> unallocated_encoding(s);
> break;
> }
>
> +insn_done:
> if (unlikely(s->singlestep_enabled) && (s->is_jmp == DISAS_TB_JUMP)) {
> /* go through the main loop for single step */
> s->is_jmp = DISAS_JUMP;
>
Ciao,
Claudio
