note.md

Next Step

I may follow the order here. https://note.mu/ruiu/n/n00ebc977fd60

1. Add/Subtract
2. Multiply/Divid
3. Local variable
4. Function call without arguments
5. Function call with arguments
6. Function declaration without arguments
7. Function declaration with arguments
8. Global variable
9. Array
10. Pointer
11. char type
12. String literal
13. Struct
14. #include

Nov 21. So far, p to the middle of 3 is done. Let's implement variable using map and vector.

Note

step 1

Need to give permission before running test.

chmod a+x test.sh

Before pushing for the first time, set upstream

Instead of just git push, do the following.

git remote add origin https://github.com/moizumi99/9cc.git
git push -u origin master

step 2

step 3

error() should be like this.

void error(char *s, int i) {
  fprintf(stderr, s, tokens[i].input);
  exit(1);
}

###mul() needs tokens[pos].ty

Inside new_node() and new_node_num(), node->op should be node->ty.

At the end of expr() and term(), they should return lhs;

step 4

Tokenizer also needs to include =

Add extraction of identifer in term()

Add new_node_ident() to create a node for an identifier.

Add assign() and program() function calls.

Add ";" at the end of each test case.

Add more tests with identifiers and value assignment.

step 7

Map struct is probably wrong

typedef struct {
  Vector *keys;
  Vector *vals;
} Map;

vec_push is probably wrong. Need sizeof(void *) * vec->capacity instead of just vec->capacity.

void vec_push(Vector *vec, void *elem) {
  if (vec->capacity == vec->len) {
    vec->capacity *= 2;
    vec->data = realloc(vec->data, sizeof(void *) * vec->capacity);
  }
  vec->data[vec->len++] = elem;
}

Syntax Tree

program: function program' program': ε | function program'

function: ident "(" expression ")" "{" line "}"

line: assign | line line': ε | assign line'

assign: expr assign' ";" assign': ε | "=" expr assign'

compare: expr compare: expr "==" expr compare: expr "!=" expr expr: mul expr: mul "+" expr expr: mul "-" expr mul: term mul: term "*" term mul: term "/" term term: number | variable | functioncall | "(" expr ")" functioncall: ident "(" arguments ")" variable: ident

arguments: ε | expr

// argument will be like below eventually. // argument: expr argument' // argument': ε | ", " expr argument'