summaryrefslogtreecommitdiff
path: root/base_cgen.c
blob: d773ba9639f2d4e859d66baefd80c9238a24813b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
/* figures out types and writes function prototypes */
/* TODO: check ferror */
typedef enum {
	  CGEN_WRITING_TO_H,
	  CGEN_WRITING_TO_C
} CGenWritingTo;
typedef struct {
	FILE *c_out;
	FILE *h_out;
	unsigned long anon_fn_count;
	unsigned long anon_var_count;
	Block *block;
	int indent_level;
	bool indent_next; /* should the next thing written be indented? */
	CGenWritingTo writing_to;
	Identifier main_ident;
} CGenerator;

static FILE *cgen_writing_to(CGenerator *g) {
	switch (g->writing_to) {
	case CGEN_WRITING_TO_H:
		return g->h_out;
	case CGEN_WRITING_TO_C:
		return g->c_out;
	}
	assert(0);
	return NULL;
}

static void cgen_indent(CGenerator *g) {
	if (g->indent_next) {
		for (int i = 0; i < g->indent_level; i++)
			fprintf(cgen_writing_to(g), "\t");
		g->indent_next = false;
	}
}

static void cgen_vwrite(CGenerator *g, const char *fmt, va_list args) {
	cgen_indent(g);
	vfprintf(cgen_writing_to(g), fmt, args);
}

static void cgen_write(CGenerator *g, const char *fmt, ...) {
	va_list args;
	va_start(args, fmt);
	cgen_vwrite(g, fmt, args);
	va_end(args);
}

/* Used to write an UNNECESSARY space */
static void cgen_space(CGenerator *g) {
	cgen_write(g, " ");
}

/* Used to write something followed by an UNNECESSARY newline */
static void cgen_writeln(CGenerator *g, const char *fmt, ...) {
	va_list args;
	va_start(args, fmt);
	cgen_vwrite(g, fmt, args);
	va_end(args);
	cgen_write(g, "\n");
	g->indent_next = true;
}
	
/* static void cgen_write_comment(CGenerator *g, const char *fmt, ...) { */
/* 	cgen_write(g, "/\* "); */
/* 	va_list args; */
/* 	va_start(args, fmt); */
/* 	cgen_vwrite(g, fmt, args); */
/* 	va_end(args); */
/* 	cgen_write(g, " *\/"); */
/* } */

static void cgen_write_line_comment(CGenerator *g, const char *fmt, ...) {
	/* could switch to // for c99 */
	cgen_write(g, "/* ");
	va_list args;
	va_start(args, fmt);
	cgen_vwrite(g, fmt, args);
	va_end(args);
	cgen_write(g, " */\n");
}


/* Pass NULL for where if you don't want to check if it's declared */
static bool cgen_fn_name(CGenerator *g, FnExpr *f, Location *where);
static bool cgen_ident(CGenerator *g, Identifier i, Location *where) {
	if (where) {
		IdentDecl *id_decl = ident_decl(i);
		if (!id_decl) {
			err_print(*where, "Identifier undeclared: %s", ident_to_str(i));
			return false;
		}
		Declaration *decl = id_decl->decl;
		if ((decl->flags & DECL_FLAG_HAS_EXPR) && (decl->flags & DECL_FLAG_CONST)) {
			if (decl->expr.kind == EXPR_FN) {
				cgen_fn_name(g, decl->expr.fn, NULL);
				return true;
			}
		}
	}
	cgen_indent(g);
	fprint_ident_reduced_charset(cgen_writing_to(g), i);
	return true;
}

static const char *builtin_type_to_str(BuiltinType b) {
	/* TODO: make this return int/long/etc. if stdint.h is not available */
	switch (b) {
	case BUILTIN_I8: return "int8_t";
	case BUILTIN_I16: return "int16_t";
	case BUILTIN_I32: return "int32_t";
	case BUILTIN_I64: return "int64_t";
	case BUILTIN_U8: return "uint8_t";
	case BUILTIN_U16: return "uint16_t";
	case BUILTIN_U32: return "uint32_t";
	case BUILTIN_U64: return "uint64_t";
	case BUILTIN_FLOAT: return "float";
	case BUILTIN_DOUBLE: return "double";
	case BUILTIN_TYPE_COUNT: break;
	}
	assert(0);
	return NULL;
}

/* will this function use a pointer parameter for output? (e.g. fn()[3]int => void(int (*x)[3]) */
static bool cgen_fn_uses_out_param(Type *fn_ret_type) {
	switch (fn_ret_type->kind) {
	case TYPE_TUPLE:
	case TYPE_ARR:
		return true;
	default:
		return false;
	}
}


static void cgen_anon_var(CGenerator *g, unsigned long v) {
	cgen_write(g, "av___%lu", v);
}

static void cgen_anon_fn(CGenerator *g, unsigned long f) {
	cgen_write(g, "af___%lu", f);
}

static void cgen_type_pre(CGenerator *g, Type *t) {
	switch (t->kind) {
	case TYPE_VOID:
		cgen_write(g, "void ");
		break;
	case TYPE_BUILTIN:
		cgen_write(g, "%s ", builtin_type_to_str(t->builtin));
		break;
	case TYPE_FN: {
		Type *types = t->fn.types.data;
		Type *ret_type = &types[0];
		if (cgen_fn_uses_out_param(ret_type)) {
			cgen_write(g, "void ");
		} else {
			cgen_type_pre(g, ret_type);
		}
		cgen_write(g, "(*");
	} break;
	case TYPE_TUPLE:
		assert(0);
		return;
	case TYPE_UNKNOWN:
		err_print(t->where, "Type of unknown-typed expression required (x := #C(\"...\") will not work; you need to annotate the type of x).");
	    abort();
	case TYPE_ARR:
		cgen_type_pre(g, t->arr.of);
		break;
	}
}

static void cgen_type_post(CGenerator *g, Type *t);
/* either pass NULL for param_types (x)or for params */
static void cgen_fn_params(CGenerator *g, Type *param_types, Param *params, size_t nparams, Type *ret_type) {
	bool uses_out_param = cgen_fn_uses_out_param(ret_type);
	   
	cgen_write(g, "(");
	if (nparams) {
		for (size_t i = 0; i < nparams; i++) {
			if (i) {
				cgen_write(g, ",");
				cgen_space(g);
			}
			if (param_types) {
				cgen_type_pre(g, &param_types[i]);
				cgen_type_post(g, &param_types[i]);
			} else {
				Param *p = &params[i];
				cgen_type_pre(g, &p->type);
				cgen_ident(g, p->name, NULL);
				cgen_type_post(g, &p->type);
			}
		}
	} else {
		if (!uses_out_param)
			cgen_write(g, "void");
	}
	if (uses_out_param) {
		if (nparams) {
			cgen_write(g, ",");
			cgen_space(g);
		}
		/* write out param */
		cgen_type_pre(g, ret_type);
		cgen_write(g, "(*out__)"); /* TODO: fix this for named return values */
		cgen_type_post(g, ret_type);
			
	}
	cgen_write(g, ")");
}

static void cgen_type_post(CGenerator *g, Type *t) {
	switch (t->kind) {
	case TYPE_VOID:
	case TYPE_BUILTIN:
		break;
	case TYPE_FN: {
		Type *types = t->fn.types.data;
		Type *ret_type = &types[0];
		Type *param_types = types + 1;
		assert(t->fn.types.len > 0);
		size_t nparams = t->fn.types.len-1;
		bool uses_out_param = cgen_fn_uses_out_param(ret_type);
		cgen_write(g, ")");
		cgen_fn_params(g, param_types, NULL, nparams, ret_type);
		if (!uses_out_param) {
			cgen_type_post(g, ret_type);
		}
		cgen_space(g);
	} break;
	case TYPE_TUPLE:
		assert(0);
		return;
	case TYPE_ARR:
		cgen_write(g, "[%lu]", t->arr.n);
		cgen_type_post(g, t->arr.of);
		break;
	case TYPE_UNKNOWN: /* we should always do pre first */
		assert(0);
		break;
	}
}

static bool cgen_fn_name(CGenerator *g, FnExpr *f, Location *where) {
	if (f->name) {
		/* TODO: check block  */
		if (f->name == g->main_ident) {
			cgen_write(g, "main__");
			return true;
		} else {
			return cgen_ident(g, f->name, where);
		}
	} else {
		cgen_anon_fn(g, f->id);
		return true;
	}
}

static bool cgen_fn_header(CGenerator *g, FnExpr *f) {
	if (!f->name || g->block != NULL) {
		cgen_write(g, "static "); /* anonymous functions only exist in this translation unit */
	}
	
	bool uses_out_param = cgen_fn_uses_out_param(&f->ret_type);
	size_t nparams = f->params.len;
	if (uses_out_param) {
		cgen_write(g, "void ");
		cgen_fn_name(g, f, NULL);
		cgen_fn_params(g, NULL, (Param*)f->params.data, nparams, &f->ret_type);
	
	} else {
	    cgen_type_pre(g, &f->ret_type);
		cgen_fn_name(g, f, NULL);
		cgen_fn_params(g, NULL, (Param*)f->params.data, nparams, &f->ret_type);
		cgen_type_post(g, &f->ret_type);
	}
	
	return true;
}

static bool cgen_block_enter(CGenerator *g, Block *b) {
	g->block = b;
	return block_enter(b, &b->stmts);
}

static bool cgen_block_exit(CGenerator *g, Block *into) {
	Block *b = g->block;
	g->block = into;
	return block_exit(b, &b->stmts);
}