On 6/27/19 7:24 PM, Mark Cave-Ayland wrote:
> For the TCG_TYPE_V128 case we have ret = TCG_REG_V2 but (ret & 31) masks
> off the top bit which converts this to TCG_REG_R2 and that's why
> tcg_out_mem_long() starts using r2 to calculate offsets.
Oh geez. Ok, I see it now.
> case TCG_TYPE_V128:
> tcg_debug_assert(ret >= 32);
> assert((offset & 15) == 0);
> - tcg_out_mem_long(s, 0, LVX, ret & 31, base, offset);
> + tcg_out_mem_long(s, 0, LVX, TCG_REG_TMP1, base, offset);
No, here ret is the register into which we are loading.
Same for the rest. The error is in tcg_out_mem_long in
trying to reuse the output register as a scratch.
> Presumably the reason this didn't break on your Power 9 box is because
> the 64-bit ABI doesn't mark r2 as reserved?
Correct. That and the fact that V0 and V1 get reserved as temporaries, so I
didn't attempt to use r1 (i.e. sp) as a temporary.
Please try the following patch on top and if it works I'll split it back into
the patch set properly.
r~
diff --git a/target/m68k/translate.c b/target/m68k/translate.c
index 2ae537461f..b61c7ea0f1 100644
--- a/target/m68k/translate.c
+++ b/target/m68k/translate.c
@@ -6124,27 +6124,34 @@ static void m68k_tr_tb_stop(DisasContextBase *dcbase,
CPUState *cpu)
{
DisasContext *dc = container_of(dcbase, DisasContext, base);
- if (dc->base.is_jmp == DISAS_NORETURN) {
- return;
- }
- if (dc->base.singlestep_enabled) {
- gen_helper_raise_exception(cpu_env, tcg_const_i32(EXCP_DEBUG));
- return;
- }
-
switch (dc->base.is_jmp) {
+ case DISAS_NORETURN:
+ break;
case DISAS_TOO_MANY:
update_cc_op(dc);
- gen_jmp_tb(dc, 0, dc->pc);
+ if (dc->base.singlestep_enabled) {
+ tcg_gen_movi_i32(QREG_PC, dc->pc);
+ gen_helper_raise_exception(cpu_env, tcg_const_i32(EXCP_DEBUG));
+ } else {
+ gen_jmp_tb(dc, 0, dc->pc);
+ }
break;
case DISAS_JUMP:
/* We updated CC_OP and PC in gen_jmp/gen_jmp_im. */
- tcg_gen_lookup_and_goto_ptr();
+ if (dc->base.singlestep_enabled) {
+ gen_helper_raise_exception(cpu_env, tcg_const_i32(EXCP_DEBUG));
+ } else {
+ tcg_gen_lookup_and_goto_ptr();
+ }
break;
case DISAS_EXIT:
/* We updated CC_OP and PC in gen_exit_tb, but also modified
other state that may require returning to the main loop. */
- tcg_gen_exit_tb(NULL, 0);
+ if (dc->base.singlestep_enabled) {
+ gen_helper_raise_exception(cpu_env, tcg_const_i32(EXCP_DEBUG));
+ } else {
+ tcg_gen_exit_tb(NULL, 0);
+ }
break;
default:
g_assert_not_reached();
