https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107570
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2022-11-08
Priority|P3 |P1
Target Milestone|--- |13.0
Ever confirmed|0 |1
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
#1 0x000000000167403c in instantiate_scev_name (
instantiate_below=<edge 0x7ffff66ea330 (3 -> 7)>,
evolution_loop=0x7ffff651a848, inner_loop=0x7ffff651a848, chrec=
<ssa_name 0x7ffff6522f30 2>, fold_conversions=0x0, size_expr=2)
at /home/rguenther/src/trunk/gcc/tree-scalar-evolution.cc:2270
2270 basic_block def_bb = gimple_bb (SSA_NAME_DEF_STMT (chrec));
(gdb) p chrec
$1 = <ssa_name 0x7ffff6522f30 2>
(gdb) p debug_tree (chrec)
<ssa_name 0x7ffff6522f30 type <error_mark 0x7ffff6517d80>
nothrow
def_stmt
version:2 in-free-list>
$2 = void
and we release the SSA name via
#0 release_ssa_name_fn (fn=0x7ffff66e9000, var=<ssa_name 0x7ffff6522f30 2>)
at /home/rguenther/src/trunk/gcc/tree-ssanames.cc:555
#1 0x000000000187eeae in release_ssa_name (name=<ssa_name 0x7ffff6522f30 2>)
at /home/rguenther/src/trunk/gcc/tree-ssanames.h:123
#2 0x0000000001881c24 in release_defs (stmt=<gimple_assign 0x7ffff66d1730>)
at /home/rguenther/src/trunk/gcc/tree-ssanames.cc:832
#3 0x00000000017bd61c in substitute_and_fold_engine::substitute_and_fold (
this=0x7fffffffda00, block=<basic_block 0x0>)
at /home/rguenther/src/trunk/gcc/tree-ssa-propagate.cc:1009
#4 0x000000000193e886 in execute_ranger_vrp (fun=0x7ffff66e9000,
warn_array_bounds_p=false, final_p=true)
at /home/rguenther/src/trunk/gcc/tree-vrp.cc:4543
#5 0x000000000193ebde in (anonymous namespace)::pass_vrp::execute (
this=0x43b16f0, fun=0x7ffff66e9000)
at /home/rguenther/src/trunk/gcc/tree-vrp.cc:4628
#6 0x00000000013b2c9d in execute_one_pass (
pass=<opt_pass* 0x43b16f0 "vrp"(204)>)
at /home/rguenther/src/trunk/gcc/passes.cc:2644
releasing SSA names while still folding looks dangerous in case the folding
eventually invokes SCEV which has a cache.
