Hasty Briefsbeta

compiler internals

共 2 篇

双语

Zig AstGen: AST => ZIR
2 months ago
- 构建AST之后，Zig编译器的下一步是使用AstGen阶段生成Zig中间表示（ZIR）。
- ZIR是一种无类型中间表示，意味着类型直到后续的编译时分析才会被完全评估。
- ZIR由一系列指令组成，每条指令带有一个标签和数据，通常引用其他指令或静态值。
- AstGen引入了作用域感知、标识符解析和字符串驻留，将字符串存储在连续数组中以便释放AST和源代码。
- ZIR指令可以嵌入静态值、通过索引引用其他指令或使用带标签的引用来引用已知原语。
- ZIR中的变量赋值不会生成显式指令，而是通过引用了值指令索引的作用域进行跟踪。
- AstGen每个文件运行一次，将整个AST急切地转换为ZIR，并且是执行标识符检查等语义验证的第一个阶段。
Zig Tokenizer
2 months ago
- Tokenization converts a stream of bytes into a stream of tokens, without handling semantics.
- Zig's tokenizer is part of the standard library, operates on a slice of bytes, produces one token at a time, and performs no allocations.
- The tokenizer stores the buffer, current index, and a pending invalid token; it moves the index forward one byte at a time.
- A token consists of a tag (enum with ~120 possible types) and a location (start and end indices).
- The next() function uses a state machine that looks one character at a time to determine the token, without peeking forward or backward.
- The implementation uses nested while loops and switches on state and character to build tokens like identifiers or keywords.
- The tokenizer's output is passed to the parser, which creates an abstract syntax tree.

首页上一页0下一页