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Add a parser grammar

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omicron 2025-03-31 14:47:58 +02:00
parent bd37ddaeea
commit 34ace36920
1 changed files with 39 additions and 0 deletions
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doc/parser_grammar.txt Normal file
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<program> ::= <statement>*
<statement> ::= <label> | <directive> | <instruction>
<label> ::= <identifier> <colon>
<directive> ::= <dot> <section_directive>
<section_directive> ::= "section" <identifier>
<instruction> ::= <identifier> <operands>
<operands> ::= <operand> ( <comma> <operand> )*
<operand> ::= <register> | <immediate> | <memory>
<immediate> ::= <number> | <label_reference>
<number> ::= <octal> | <binary> | <decimal> | <hexadecimal>
<label_reference> ::= <identifier>
<memory> ::= <lbracket> <memory_expression> <rbracket>
<memory_expression> ::= <label_reference> | <register_expression>
<register_expression> ::= <register> <register_index>? <register_offset>?
<register_index> ::= <plus> <register> <asterisk> <number>
<register_offset> ::= <plus_or_minus> <number>
<plus_or_minus> ::= <plus> | <minus>
/* These are lexer identifiers with the correct string value */
<section> ::= "section"
<register> ::= "rax" | "rbx" | "rcx" | "rdx" | "rsi" | "rdi" | "rbp" | "rsp" |
"r8" | "r9" | "r10" | "r11" | "r12" | "r13" | "r14" | "r15"