Hydrogen 语言大纲

[toc] ## 1. 语法文档 ### 1.1 变量变量声明 ```go i32 f1; // 整型字变量默认为i32,支持自动类型转换 f32 f2; i32[5] f3; // 数组声明 f32[93] f4; ``` #### 支持的数值类型 | 实数类型 | 数组类型 | | -------- | ------------ | | i32 | i32[num-int] | | f32 | f32[num-int] | ### 1.2 注释 #### 单行注释单行注释使用 `//` 开头，后面跟随注释内容。例如： ``` // 这是一个单行注释 ``` #### 多行注释多行注释使用 `/*` 开头，并以 `*/` 结束。例如： ``` /* 这是一个多行注释可以跨越多行 */ ``` ### 1.3 控制结构 #### if 语法 ``` if condition { // 当 condition 为 true 时执行的代码 } else { // 当 condition 为 false 时执行的代码 } ``` condition 的类型必须是 bool 可以使用 else 语法来检查多个条件，示例: ``` fn main() { i32 type; i32 foo; age = 32; if foo >= 60 { a = 0; } else { if foo >= 18 { a = 1; } else { a = 2; } } } ``` #### While 语法 `while` 语句用于循环执行代码块。Nature 语言中的 `for` 语句有三种主要形式：经典循环、条件循环。 - **经典循环** 经典循环用于执行固定次数的循环。基本语法如下： ``` fn main() { i32 a; i32 sum; a = 0; sum = 0; while a <= 100 { sum = sum + a; a = a + 1; } } ``` 在这个示例中，循环从 `i = 1` 开始，每次循环 `i` 增加 1，直到 `i` 大于 100。 - 1.5 算术运算符 | 优先级 | 关键字 | 使用示例 | 说明 | | ------ | ------ | -------------- | ---------------------- | | 1 | () | (1 + 1) | (expr) | | 2 | / | 1 / 2 | 除 | | 2 | * | 1 * 2 | 乘 | | 2 | % | 5 % 2 | 余数 | | 3 | + | 1 + 1 | 加 | | 3 | - | 1 - 1 | 减 | | 4 | > | 1 > 2 | 大于 | | 4 | >= | 1 >= 2 | 大于等于 | | 4 | < | 1 < 2 | 小于 | | 4 | <= | 1 <= 2 | 小于等于 | | 4 | == | 1 == 2 | 等于 | | 4 | != | 1 != 2 | 不等于 | ### 1.4 函数函数声明语法如下 ```` fn 函数名(参数名:参数类型,....) -> 返回类型 { ... } ```` > 注意： -> 返回类型可以省略，省略后默认返回void > > 例子： ``` fn main() { return 0; } ``` ## 2. 实现细节 ### 2.1 符号表 #### 全局变量表 | Name | Type | Width | Offset | | ---- | ---- | ----- | ------ | | g_a | i32 | 4 | 0 | | | | | | #### 函数表 | Function Name | Return Type | Local Var Table | | ------------- | ----------- | --------------- | | main | void | main | #### 局部变量表表名称：main | Name | Type | Width | Offset | Is Param | | ---- | ----- | ----- | ------ | -------- | | test | i32 | 4 | 0 | True | | a | i32[] | 128 | 4 | False | | | | | | | | | | | | | ### 2.2 四元式 1. **函数定义** - 表示函数入口，例如：(fun, _, _, main)（定义主函数）。 2. **赋值操作** - 将常量或变量赋给临时变量或目标变量，例如： - (=, 32, _, _v0)（常量赋值） - (=, _v0, _, age)（变量赋值） - (=, 0, _, _v18)（常量赋值给临时变量）。 3. **比较操作** - 包括大于等于 (>=) 和小于等于 (<=)，生成布尔结果，例如： - (>=, foo, _v1, _v2) - (<=, foo, _v10, _v11) 4. **条件跳转** - 根据条件判断跳转到指定基本块，例如：(if, _v3, goto, __b3)。 5. **无条件跳转** - 直接跳转到指定基本块，例如：(goto, _, _, __b5)。 6. **基本块标记** - 定义控制流中的基本块，例如：(block, _, _, __b3)。 7. **算术操作** - 执行加法运算，例如：(+, age, a, _v13)。 8. **返回操作** - 表示函数返回特定值，例如：(return, _, _, _v18)（返回临时变量 _v18 的值）。 9. **函数调用** - 表示调用函数，例如：(call, product, 0, _) （product是函数名，0是参数个数）。 ### 2.3 添加语义动作的文法推导式 ```python # 0 Production('program', ['define-lists'], 'Program0S', [None], 'Program0E'), # 1 Production('define-lists', ['define-list', 'define-lists'], None, [None, None], 'DefineLists1E'), # 2 Production('define-lists', [], None, [], 'DefineLists2E'), # 3 Production('define-list', ['fun-define'], None, [None], 'DefineList3E', ), # 4 Production('define-list', ['global-var-define'], None, [None], 'DefineList4E', ), # 5 Production('fun-define', ['fn', 'id', 'left-parentheses', 'params', 'right-parentheses', 'fun-return', 'left-brace', 'code-block', 'right-brace'], None, [None, None, None, 'FunDefine5C3', None, 'FunDefine5C5', None, 'FunDefine5C7', None], 'FunDefine5E', ), # 6 Production('params', [], 'Params6S', [], None, ), # 7 Production('params', ['paramlist'], 'Params7S', ['Params7C0'], None, ), # 8 Production('paramlist', ['param', 'param-follow'], None, ['ParamList8C0', 'ParamList8C1'], None, ), # 9 Production('param-follow', ['comma', 'param', 'param-follow'], None, [None, 'ParamFollow9C1', 'ParamFollow9C2'], None, ), # 10 Production('param-follow', [], None, [], None, ), # 11 Production('param', ['id', 'colon', 'type', 'arraylist'], None, [None, None, None, None], 'Param11E', ), # 12 Production('arraylist', [], 'ArrayList12S', [], None, ), # 13 Production('arraylist', ['left-bracket', 'right-bracket'], 'ArrayList13S', [None, None], None, ), # 14 Production('fun-return', [], 'FunReturn14S', [], None, ), # 15 Production('fun-return', ['right-arrow', 'type', 'arraylist'], None, [None, None, None], 'FunReturn15E', ), # 16 Production('type', ['i32'], 'Type16S', [None], None, ), # 17 Production('type', ['f32'], 'Type17S', [None], None, ), # 18 Production('type', ['void'], "Type18S", [None], None, ), # 19 Production('global-var-define', ['type', 'arraylist-with-num', 'id', 'global-var-define-follow'], None, [None, None, None, 'GlobalVarDefine19C3'], 'GlobalVarDefine19E', ), # 20 Production('global-var-define-follow', ['comma', 'id', 'global-var-define-follow'], None, [None, None, 'GlobalVarDefineFllow20C2'], 'GlobalVarDefineFllow20E', ), # 21 Production('global-var-define-follow', ['semicolon'], None, [None], None, ), # 22 Production('code-block', ['code-list'], None, ['CodeBlock22C0'], 'CodeBlock22E', ), # 23 Production('code-list', ['code', 'code-list'], None, ["CodeList23C0", 'CodeList23C1'], 'CodeList23E', ), # 24 Production('code-list', [], None, [], 'CodeList24E', ), # 25 Production('code', ['local-define'], None, ['Code25C0'], 'Code25E', ), # 26 Production('code', ['normal-statement'], None, ['Code26C0'], 'Code26E', ), # 27 Production('code', ['selection-statement'], None, ['Code27C0'], 'Code27E', ), # 28 Production('code', ['iteration-statement'], None, ['Code28C0'], 'Code28E', ), # 29 Production('code', ['return-statement'], None, ['Code29C0'], 'Code29E', ), # 30 Production('local-define', ['type', 'arraylist-with-num', 'id', 'local-define-follow'], None, ['LocalDefine30C0', "LocalDefine30C1", 'LocalDefine30C2', 'LocalDefine30C3'], 'LocalDefine30E', ), # 31 Production('local-define-follow', ['comma', 'id', 'local-define-follow'], None, [None, 'LocalDefineFollow31C1', 'LocalDefineFollow31C2'], 'LocalDefineFollow31E', ), # 32 Production('local-define-follow', ['semicolon'], None, [None], None, ), # 33 Production('normal-statement', ['semicolon'], None, [None], None, ), # 34 Production('normal-statement', ['id', 'normal-statement-follow'], None, [None, 'NormalStatement34C1'], 'NormalStatement34E', ), # 35 Production('normal-statement-follow', ['var-follow', 'evaluate', 'exp', 'semicolon'], None, ['NormalStatementFollow35C0', None, 'NormalStatementFollow35C2', None], 'NormalStatement35E', ), # 36 Production('normal-statement-follow', ['call-follow', 'semicolon'], None, ['NormalStatementFollow36C0', None], 'NormalStatementFollow36E', ), # 37 Production('var-follow', [], None, [], 'VarFollow37E', ), # 38 Production('var-follow', ['left-bracket', 'exp', 'right-bracket'], None, [None, None, None], 'VarFollow38E', ), # 39 Production('call-follow', ['left-parentheses', 'call-params', 'right-parentheses'], None, [None, 'CallFollow39C1', None], 'CallFollow39E', ), # 40 Production('call-params', ['call-param-list'], None, ['CallParams40C0'], 'CallParams40E', ), # 41 Production('call-params', [], None, [], 'CallParams41E', ), # 42 Production('call-param-list', ['exp', 'call-param-follow'], None, ['CallParamList42C0', None], 'CallParamList42E', ), # 43 Production('call-param-follow', ['comma', 'exp', 'call-param-follow'], None, [None, 'CallParamFollow43C1', None], 'CallParamFollow43E', ), # 44 Production('call-param-follow', [], None, [], 'CallParamFollow44E', ), # 45 Production('selection-statement', ['if', 'exp', 'left-brace', 'code-list', 'right-brace', 'selection-follow'], None, [None, 'SelectionStatement45C1', None, 'SelectionStatement45C3', None, 'SelectionStatement45C5'], 'SelectionStatement45E', ), # 46 Production('selection-follow', ['else', 'left-brace', 'code-list', 'right-brace'], None, [None, None, 'SelectionFollow46C2', None], 'SelectionFollow46E', ), # 47 Production('selection-follow', [], None, [], 'SelectionFollow47E', ), # 48 Production('iteration-statement', ['while', 'exp', 'left-brace', 'code-list', 'right-brace'], None, [None, "IterationStatement48C1", None, 'IterationStatement48C3', None], 'IterationStatement48E', ), # 49 Production('return-statement', ['return', 'return-follow'], None, [None, 'ReturnStatement49C1'], "ReturnStatement49E", ), # 50 Production('return-follow', ['semicolon'], None, [None], "ReturnFollow50E", ), # 51 Production('return-follow', ['exp', 'semicolon'], None, ['ReturnFollow51C0', None], 'ReturnFollow51E', ), # 52 Production('exp', ['additive-expr', 'exp-follow'], None, ['Exp52C0', 'Exp52C1'], 'Exp52E'), # 53 Production('exp-follow', ['rel-op', 'additive-expr'], None, [None, 'ExpFollow53C1'], 'ExpFollow53E'), # 54 Production('exp-follow', [], None, [], 'ExpFollow54E'), # 55 Production('rel-op', ['smaller-equal'], None, [None], 'RelOp55E'), # 56 Production('rel-op', ['smaller'], None, [None], 'RelOp56E'), # 57 Production('rel-op', ['bigger'], None, [None], 'RelOp57E'), # 58 Production('rel-op', ['bigger-equal'], None, [None], 'RelOp58E'), # 59 Production('rel-op', ['equal'], None, [None], 'RelOp59E'), # 60 Production('rel-op', ['not-equal'], None, [None], 'RelOp60E'), # 61 Production('additive-expr', ['term', 'additive-expr-follow'], None, ['AdditiveExpr61C0', 'AdditiveExpr61C1'], 'AdditiveExpr61E'), # 62 Production('additive-expr-follow', ['add-op', 'term', 'additive-expr-follow'], None, [None, 'AdditiveExprFollow62C1', 'AdditiveExprFollow62C2'], 'AdditiveExprFollow62E'), # 63 Production('additive-expr-follow', [], None, [], 'AdditiveExprFollow63E'), # 64 Production('add-op', ['addition'], None, [None], 'AddOp64E'), # 65 Production('add-op', ['subtraction'], None, [None], 'AddOp65E'), # 66 Production('term', ['factor', 'term-follow'], None, ['Term66C0', 'Term66C1'], 'Term66E'), # 67 Production('term-follow', ['mul-op', 'factor', 'term-follow'], None, [None, 'TermFollow67C1', 'TermFollow67C2'], 'TermFollow67E'), # 68 Production('term-follow', [], None, [], 'TermFollow68E'), # 69 Production('mul-op', ['multiplication'], None, [None], 'MulOp69E'), # 70 Production('mul-op', ['division'], None, [None], 'MulOp70E'), # 71 Production('factor', ['left-parentheses', 'exp', 'right-parentheses'], None, [None, 'Factor71C1', None], 'Factor71E'), # 72 Production('factor', ['id', 'id-factor-follow'], None, [None, 'Factor72C1'], 'Factor72E'), # 73 Production('factor', ['int-num'], None, [None], 'Factor73E'), # 74 Production('id-factor-follow', ['var-follow'], None, [None], 'IdFactorFollow74E'), # 75 Production('id-factor-follow', ['left-parentheses', 'args', 'right-parentheses'], None, [None, 'IdFactorFollow75C1', None], 'IdFactorFollow75E'), # 76 Production('args', ['arg-list'], None, ['Args76C0'], 'Args76E'), # 77 Production('args', [], None, [], 'Args77E'), # 78 Production('arg-list', ['exp', 'arg-list-follow'], None, ['ArgList78C0', 'ArgList78C1'], 'ArgList78E'), # 79 Production('arg-list-follow', ['comma', 'exp', 'arg-list-follow'], None, [None, 'ArgListFollow79C1', 'ArgListFollow79C2'], 'ArgListFollow79E'), # 80 Production('arg-list-follow', [], None, [], 'ArgListFollow80E'), # 81 Production('arraylist-with-num', [], None, [], 'ArrayListWithNum81E', ), # 82 Production('arraylist-with-num', ['left-bracket', 'int-num', 'right-bracket'], None, [None, None, None], 'ArrayListWithNum82E', ), # 83 Production('factor', ['float-num'], None, [None], 'Factor83E'), # 84 Production('mul-op', ['yushu'], None, [None], 'MulOp84E'), ```