https://gcc.gnu.org/bugzilla/show_bug.cgi?id=122637
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Assignee|unassigned at gcc dot gnu.org |pinskia at gcc dot
gnu.org
Last reconfirmed| |2025-11-11
Status|UNCONFIRMED |ASSIGNED
Ever confirmed|0 |1
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
analyze_scalar_evolution_1 (loop=0x7ffff7468190, var=0x7ffff7216000) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-scalar-evolution.cc:1989
1989 def_loop = bb->loop_father;
#1 0x00000000013776d3 in analyze_scalar_evolution (loop=0x7ffff7468190,
var=0x7ffff7216000) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-scalar-evolution.cc:2081
#2 0x000000000144117a in idx_infer_loop_bounds
(base=base@entry=0x7ffff77e5000, idx=idx@entry=0x7ffff77e5020,
dta=dta@entry=0x7fffffffa7b0) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:4304
#3 0x0000000001456cd9 in for_each_index (addr_p=<optimized out>,
addr_p@entry=0x7fffffffa760, cbck=cbck@entry=0x1441100
<idx_infer_loop_bounds(tree, tree*, void*)>, data=data@entry=0x7fffffffa7b0) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop.cc:576
#4 0x000000000143d3d4 in infer_loop_bounds_from_ref (loop=0x7ffff7468190,
stmt=0x7ffff721b6e0, ref=0x7ffff77e5000) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:4385
#5 infer_loop_bounds_from_array (loop=<optimized out>, stmt=0x7ffff721b6e0) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:4406
#6 infer_loop_bounds_from_undefined (loop=<optimized out>, bbs=<optimized
out>) at /home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:4565
#7 estimate_numbers_of_iterations (loop=0x7ffff7468190) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:5030
#8 0x00000000014404f4 in loop_exits_before_overflow (base=0x7ffff781f150,
step=0x7ffff7714720, at_stmt=0x7ffff7233300, loop=0x7ffff7468190) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:5417
#9 scev_probably_wraps_p (var=var@entry=0x0, base=base@entry=0x7ffff781f150,
step=step@entry=0x7ffff7714720, at_stmt=at_stmt@entry=0x7ffff7233300,
loop=0x7ffff7468190, use_overflow_semantics=use_overflow_semantics@entry=true)
at /home/apinski/src/upstream-gcc-git/gcc/gcc/tree-ssa-loop-niter.cc:5669
#10 0x00000000016b0153 in get_scev_info (r=..., name=0x7ffff76d89c0,
stmt=<optimized out>, l=0x7ffff7468190, init=<synthetic pointer>:
0x7ffff781f150, step=@0x7fffffffaa98: 0x7ffff7714720, dir=@0x7fffffffaaa8:
EV_DIR_GROWS) at /home/apinski/src/upstream-gcc-git/gcc/gcc/vr-values.cc:237
#11 range_of_var_in_loop (v=..., name=name@entry=0x7ffff7212420,
l=0x7ffff7468190, stmt=0x7ffff7233300, query=0x39b3c90) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/vr-values.cc:304
#12 0x0000000000e82e7c in fold_using_range::range_of_ssa_name_with_loop_info
(this=<optimized out>, r=..., name=0x7ffff7212420, l=<optimized out>,
phi=<optimized out>, src=...) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range-fold.cc:1278
#13 0x0000000000e83625 in fold_using_range::range_of_phi (this=0x7fffffffbfc0,
r=..., phi=0x7ffff7233300, src=...) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range-fold.cc:1032
#14 0x0000000000e87461 in fold_using_range::fold_stmt (this=0x7fffffffbfc0,
r=..., s=0x7ffff7233300, src=..., name=0x7ffff7212420) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range-fold.cc:651
#15 0x0000000000e70706 in gimple_ranger::fold_range_internal (this=0x39b3c90,
r=..., s=0x7ffff7233300, name=<optimized out>) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range.cc:282
#16 gimple_ranger::prefill_stmt_dependencies (this=0x39b3c90,
ssa=0x7ffff721bc60) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range.cc:421
#17 0x0000000000e7160b in gimple_ranger::range_of_stmt (this=0x39b3c90, r=...,
s=0x7ffff77c4420, name=<optimized out>) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range.cc:339
#18 0x0000000000e7311e in gimple_ranger::range_of_expr (this=0x39b3c90, r=...,
expr=0x7ffff721bc60, stmt=<optimized out>) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-range.cc:112
#19 0x00000000012d13c8 in get_ref_base_and_extent (exp=0x7ffff77e5498,
exp@entry=0x7ffff77e5460, poffset=poffset@entry=0x7fffffffd400,
psize=psize@entry=0x7fffffffd408, pmax_size=pmax_size@entry=0x7fffffffd410,
preverse=preverse@entry=0x7fffffffd3ff) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-dfa.cc:542
#20 0x0000000000e580a2 in fold_const_aggregate_ref_1 (t=0x7ffff77e5460,
valueize=0x0) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-fold.cc:10285
#21 0x0000000000e597a6 in fold_const_aggregate_ref (t=<optimized out>) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-fold.cc:10382
#22 maybe_fold_reference (expr=<optimized out>) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-fold.cc:326
#23 0x0000000000e5bd3d in fold_gimple_assign (si=0x7fffffffd620) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-fold.cc:474
#24 fold_stmt_1 (gsi=0x7fffffffd620, inplace=false, valueize=<optimized out>,
dce_worklist=<optimized out>) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/gimple-fold.cc:6809
#25 0x00000000012b48f1 in replace_uses_by (name=name@entry=0x7ffff7216000,
val=val@entry=0x7ffff781f300) at
/home/apinski/src/upstream-gcc-git/gcc/gcc/tree-cfg.cc:1992
Getting the order correct this time I think.
```
diff --git a/gcc/tree-scalar-evolution.cc b/gcc/tree-scalar-evolution.cc
index 180df75311f..8b100b733b7 100644
--- a/gcc/tree-scalar-evolution.cc
+++ b/gcc/tree-scalar-evolution.cc
@@ -3952,6 +3952,11 @@ final_value_replacement_loop (class loop *loop)
gimple_seq stmts;
def = force_gimple_operand (def, &stmts, false, NULL_TREE);
+ /* Propagate constants immediately, but leave an unused initialization
+ around to avoid invalidating the SCEV cache. */
+ if (CONSTANT_CLASS_P (def) && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rslt))
+ replace_uses_by (rslt, def);
+
/* Remove the old phi after the gimplification to make sure the
SSA name is defined by a statement so that fold_stmt during
the gimplification does not crash. */
@@ -3960,11 +3965,6 @@ final_value_replacement_loop (class loop *loop)
gimple_set_location (ass, loc);
gimple_seq_add_stmt (&stmts, ass);
- /* Propagate constants immediately, but leave an unused initialization
- around to avoid invalidating the SCEV cache. */
- if (CONSTANT_CLASS_P (def) && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (rslt))
- replace_uses_by (rslt, def);
-
/* If def's type has undefined overflow and there were folded
casts, rewrite all stmts added for def into arithmetics
with defined overflow behavior. */
```
So gimplify, then replace and then remova the phi.
