style: compact comments in language runtime

This commit is contained in:
Pepijn
2026-07-15 13:52:52 +02:00
parent 1eed8df1c4
commit 7c125c0028
20 changed files with 205 additions and 917 deletions
@@ -56,17 +56,9 @@ def _shifted_ce(logits, labels):
eye = torch.eye(vocab_size, dtype=logits.dtype, device="cuda")
return _shifted_lin_ce(logits.cuda(), eye, labels.cuda()).cpu()
# ---------------------------------------------------------------------------
# A synthetic PI052 prefix layout: [images, prompt-lang, target-lang]
#
# indices 0-1 : 2 image tokens (att = 0)
# indices 2-4 : 3 user-prompt lang (att = 0)
# indices 5-8 : 4 supervised target lang(att = 0 from embed_prefix)
#
# ``text_labels`` covers the 7 language tokens; -100 on the prompt span,
# real ids on the 4-token target span. PaliGemma's prefix has no state
# token (unlike SmolVLA), so the lang span ends at the prefix end.
# ---------------------------------------------------------------------------
# Synthetic prefix: two image tokens, three prompt tokens, and four supervised target tokens.
# Text labels mask the prompt with -100 and cover the target through the prefix end.
N_IMAGE = 2
N_PROMPT = 3
N_TARGET = 4
@@ -95,9 +87,7 @@ def _attends(prefix_att_masks: torch.Tensor) -> torch.Tensor:
def test_mark_sets_att_on_targets_only():
"""Only the supervised target language positions flip to att=1."""
marked = _mark_target_span_causal(
_embed_prefix_att_masks(), _text_labels(), LANG_START, LANG_END
)
marked = _mark_target_span_causal(_embed_prefix_att_masks(), _text_labels(), LANG_START, LANG_END)
expected = [False] * PREFIX_LEN
for i in range(LANG_START + N_PROMPT, LANG_END): # target span
expected[i] = True
@@ -107,9 +97,7 @@ def test_mark_sets_att_on_targets_only():
def test_target_tokens_attend_causally_among_themselves():
"""A target token must NOT attend to later targets, but must attend
to earlier ones — genuine causal next-token prediction."""
marked = _mark_target_span_causal(
_embed_prefix_att_masks(), _text_labels(), LANG_START, LANG_END
)
marked = _mark_target_span_causal(_embed_prefix_att_masks(), _text_labels(), LANG_START, LANG_END)
attends = _attends(marked)
tgt = range(LANG_START + N_PROMPT, LANG_END)
for i in tgt:
@@ -122,9 +110,7 @@ def test_target_tokens_attend_causally_among_themselves():
def test_target_tokens_attend_prompt_and_images_bidirectionally():
"""Targets keep full visibility of images + the user prompt."""
marked = _mark_target_span_causal(
_embed_prefix_att_masks(), _text_labels(), LANG_START, LANG_END
)
marked = _mark_target_span_causal(_embed_prefix_att_masks(), _text_labels(), LANG_START, LANG_END)
attends = _attends(marked)
context = list(range(0, LANG_START + N_PROMPT)) # images + prompt
for i in range(LANG_START + N_PROMPT, LANG_END):
@@ -136,9 +122,7 @@ def test_non_target_subtask_stays_bidirectional():
"""A flow-only / non-target language span (all -100 labels) leaves the
mask untouched — the action expert reads it bidirectionally."""
all_ignored = torch.full((1, N_PROMPT + N_TARGET), -100, dtype=torch.long)
marked = _mark_target_span_causal(
_embed_prefix_att_masks(), all_ignored, LANG_START, LANG_END
)
marked = _mark_target_span_causal(_embed_prefix_att_masks(), all_ignored, LANG_START, LANG_END)
assert torch.equal(marked, _embed_prefix_att_masks())