Benchy cannot run PC1 only

[vmx]

Description

Benchy cannot be run on PC1 only. When you skip all stages except for PC1 there will be a could not read file phase2_output_path error.

Steps to reproduce:

$ cargo run --bin benchy -- window-post --cache /tmp/window-post-2KiB-dir --skip-precommit-phase2 --skip-commit-phase1 --skip-commit-phase2 --size 2KiB
    Finished dev [unoptimized + debuginfo] target(s) in 0.44s
     Running `target/debug/benchy window-post --cache /tmp/window-post-2KiB-dir --skip-precommit-phase2 --skip-commit-phase1 --skip-commit-phase2 --size 2KiB`
Error: could not read file phase2_output_path="/tmp/window-post-2KiB-dir/precommit-phase2-output"

It should be possible to run PC1 without having to run any other stages first.

Acceptance criteria

The command above does the PC1 step without errors. You should not need to run anything before this step.

Risks + pitfalls

Don't break skipping other stages.

Where to begin

Check the bency source for phase2_output_path and figure out why it checks for it early on.

[RobQuistNL]

Thanks for opening this 👍

I'd love a way to run AP + PC1 and then cache the AddPiece (unsealed sector) to run the PC1 against.