Jeff Law <j...@ventanamicro.com> writes:
> On 11/7/23 17:35, Richard Sandiford wrote:
>
>> I could have sworn that there was something that checked that passes
>> left edge aux fields clear, but it looks like I misremembered. So I
>> probably need to stick a clear_aux_for_edges () call above the first
>> main loop (for 12/12) and keep the initialisation here as well.
> That does sound vaguely familiar. Maybe it was a one-off test someone
> did.
>
>>
>> That kind-of takes away the point of shifting to 1-based values
>> in the first place. Ah well...
> Your call. I'd tend to lean towards inserting the clear_aux call if we
> don't have something that's consistently verifying aux state.
Agreed. A convention that isn't tested isn't strong enough to rely on.
> Alternately we can return to the -1 handling. I doubt it's all that
> important from a compile-time standpoint.
I dithered about it a bit, but in the end, zero does still seem to work
out a bit more nicely.
I think you'd basically OKed the patch with this change, but I'm feeling
extra risk-averse at the moment :) so, here's an updated patch.
Tested as before. OK to install?
Thanks for catching this.
Richard
gcc/
* mode-switching.cc (commit_mode_sets): Use 1-based edge aux values.
---
gcc/mode-switching.cc | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/gcc/mode-switching.cc b/gcc/mode-switching.cc
index 7a5c4993d65..6b5661131e3 100644
--- a/gcc/mode-switching.cc
+++ b/gcc/mode-switching.cc
@@ -106,10 +106,10 @@ commit_mode_sets (struct edge_list *edge_list, int e,
struct bb_info *info)
for (int ed = NUM_EDGES (edge_list) - 1; ed >= 0; ed--)
{
edge eg = INDEX_EDGE (edge_list, ed);
- int mode;
- if ((mode = (int)(intptr_t)(eg->aux)) != -1)
+ if (eg->aux)
{
+ int mode = (int) (intptr_t) eg->aux - 1;
HARD_REG_SET live_at_edge;
basic_block src_bb = eg->src;
int cur_mode = info[src_bb->index].mode_out;
@@ -728,14 +728,14 @@ optimize_mode_switching (void)
{
edge eg = INDEX_EDGE (edge_list, ed);
- eg->aux = (void *)(intptr_t)-1;
+ eg->aux = (void *) (intptr_t) 0;
for (i = 0; i < no_mode; i++)
{
int m = targetm.mode_switching.priority (entity_map[j], i);
if (mode_bit_p (insert[ed], j, m))
{
- eg->aux = (void *)(intptr_t)m;
+ eg->aux = (void *) (intptr_t) (m + 1);
break;
}
}
--
2.25.1
