syntax_data: {"ast_node_type":"other","tokens":[{"end":60,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:     // FEAT_SVE_B16B16 (SVE or SME Z-targeting instructions)
context_before:     ("sve", Stable, &["neon"]),
context_after:     ("sve-b16b16", Unstable(sym::aarch64_unstable_target_feature), &["bf16"]),