https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121474
Bug ID: 121474
Summary: [16 Regression] investigate only having alias walk in
forwprop1 or at -O2+
Product: gcc
Version: 16.0
Status: UNCONFIRMED
Keywords: compile-time-hog
Severity: enhancement
Priority: P3
Component: tree-optimization
Assignee: pinskia at gcc dot gnu.org
Reporter: pinskia at gcc dot gnu.org
Target Milestone: ---
As mentioned in
https://gcc.gnu.org/pipermail/gcc-patches/2025-August/692091.html.
"
Oh, as we now do alias walks in forwprop maybe we should make this
conditional and do
this not for all pass instances, since it makes forwprop possibly a lot slower?
"
We should limit the alias walk to only a few of the forwprop and maybe have an
option to turn it on/off.
I am thinking we could do it in forwprop1 and forwprop2 only. I need to gather
some stats on if I see a case where it happens in forwprop3 or 4. for zero
prop; I have not seen one yet; only in forwprop1 (before inline, after einline)
and forwprop2 (right after inlining).
