syntax_data: {"ast_node_type":"other","tokens":[{"end":49,"kind":"keyword","start":0,"text":"cx:"}]}
source_snippet:         cx: reg, reg_abcd = ["cx", "ecx", "rcx"],
context_before:         bx: reg, reg_abcd = ["bx", "ebx", "rbx"] % rbx_reserved,
context_after:         dx: reg, reg_abcd = ["dx", "edx", "rdx"],