GS/HW: Allow creation of known targets via move with offset

[stenzek]

Description of Changes

Devil May Cry is pretty whacky. It copies the framebuffer at FBP 0x0 to 0x1400 (at the full size...), then draws the subtitle on the copied framebuffer. But it only copies the bottom chunk of it, not the whole thing (512x32 in this example). And it doesn't copy it with a draw, it copies it with a move.

Then it uses the PCRTC to blend the two framebuffers together. Currently, this falls apart, because the heuristic to create a new target via move relies on the destination offset being zero. Which is isn't here, because it's only copying the bottom part of the FB.

So, leverage the hash cache to allow previously-known targets to be created for moves, which means it all happens in hardware (no readback), and preserves upscaling. We also have to inject the clears into the hash cache as well, because this subtitle-framebuffer gets cleared before moved to, not drawn.

Rationale behind Changes

Fixes upscaling with subtitles in Devil May Cry, and gets rid of the readback.

Suggested Testing Steps

Check DMC.

[bigol83]

Can confirm this fixes the subtitles upscaling, nice job 👍

Though there is still an issue with subtitles corrupting the fmv videos, like intro, even at native resolution.
Devil May Cry_SLES-50358_20240414125502.gs.zip

[stenzek]

Separate issue, unrelated to this PR. Please open an issue for it.

Details: Two layers, it writes the background, but never draws to the target, so the transfer list gets destroyed, and by the time it gets picked up by the PCRTC on the next frame, it has no history of the writes.

[bigol83]

Ok, will open a new issue.