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[willtebbutt]

Resolves a problem that @sunxd3 encountered when generating a large unrolled IR.

I've yet to produce a MWR, but will attempt to do so before merging. @sunxd3 could you run this branch on your problem to confirm that it indeed resolves the issue? (it does on my machine, I'm just keen to ensure that it does also on other machines)

edit: I do not understand why this resolves the problem. Presumably there is some limitation of vcat(x...) that tends not to be hit.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Files with missing lines	Coverage Δ
src/interpreter/s2s_reverse_mode_ad.jl	92.65% <100.00%> (ø)

[github-actions]

Performance Ratio:
Ratio of time to compute gradient and time to compute function.
Warning: results are very approximate! See here for more context.

┌────────────────────────────┬──────────┬──────────┬─────────────┬─────────┐
│                      Label │ Mooncake │   Zygote │ ReverseDiff │  Enzyme │
│                     String │   String │   String │      String │  String │
├────────────────────────────┼──────────┼──────────┼─────────────┼─────────┤
│                   sum_1000 │     69.7 │      1.0 │         5.5 │ missing │
│                  _sum_1000 │     6.76 │ 339000.0 │        33.1 │ missing │
│               sum_sin_1000 │     2.29 │     1.73 │        10.6 │ missing │
│              _sum_sin_1000 │     2.75 │    243.0 │        13.8 │ missing │
│                   kron_sum │     60.1 │     5.47 │       213.0 │ missing │
│              kron_view_sum │     21.3 │     3.49 │        87.2 │ missing │
│      naive_map_sin_cos_exp │     2.56 │  missing │        7.33 │ missing │
│            map_sin_cos_exp │     2.78 │     1.43 │        6.16 │ missing │
│      broadcast_sin_cos_exp │     3.08 │     3.04 │        1.46 │ missing │
│                 simple_mlp │     4.56 │     2.03 │        9.97 │ missing │
│                     gp_lml │     4.43 │     2.21 │     missing │ missing │
│ turing_broadcast_benchmark │     3.85 │  missing │        24.8 │ missing │
│         large_single_block │     4.15 │   3910.0 │        31.1 │ missing │
└────────────────────────────┴──────────┴──────────┴─────────────┴─────────┘

[sunxd3]

can confirm that the fix works, thanks

[willtebbutt]

Excellent. Since I really don't have any idea how to construct a MWE, and I don't have the time to dig around at the minute, I'm going to merge + tag this. If a similar problem appears, I'll try harder to great a MWE to tie it down.