On 2015-12-08 10:43, TeLeMan wrote:
> I know MAX_CODE_GEN_BUFFER_SIZE is limited by the host direct branch
> instructions.But the arm's MAX_CODE_GEN_BUFFER_SIZE is so small.I
> tried improving MAX_CODE_GEN_BUFFER_SIZE.I wrote some check codes for
> the overflow offset in tcg_out_b(), tcg_out_bl(),
> tcg_out_blx_imm(),reloc_pc24(). But I didn't catch any overflow case
> when tb_size and MAX_CODE_GEN_BUFFER_SIZE were larger than 32MB. After
> the generated code size was larger than 32MB, qemu crashed.
Instrumenting all the tcg_out_* branch related functions do not work
here as the address is actually not known at code generation:
case INDEX_op_goto_tb:
if (s->tb_jmp_offset) {
/* Direct jump method */
s->tb_jmp_offset[args[0]] = tcg_current_code_size(s);
tcg_out_b_noaddr(s, COND_AL);
It is patched later during TB linking.
> Any suggest for this issue?
I already posted a patch a long time ago to remove the 16MB limit on ARM
hosts:
http://lists.gnu.org/archive/html/qemu-devel/2012-10/msg01684.html
However as you can see in the thread, it has been rejected as it doesn't
not bring improvement in all cases.
Aurelien
--
Aurelien Jarno GPG: 4096R/1DDD8C9B
aurel...@aurel32.net http://www.aurel32.net
