compile.c 154 KB
Newer Older
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
/*
 * This file is part of the Micro Python project, http://micropython.org/
 *
 * The MIT License (MIT)
 *
 * Copyright (c) 2013, 2014 Damien P. George
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

xbe's avatar
xbe committed
27
#include <stdbool.h>
Damien's avatar
Damien committed
28
29
30
31
32
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

33
34
35
36
37
38
#include "py/scope.h"
#include "py/emit.h"
#include "py/compile.h"
#include "py/smallint.h"
#include "py/runtime.h"
#include "py/builtin.h"
Damien's avatar
Damien committed
39
40
41
42

// TODO need to mangle __attr names

typedef enum {
43
#define DEF_RULE(rule, comp, kind, ...) PN_##rule,
44
#include "py/grammar.h"
Damien's avatar
Damien committed
45
46
#undef DEF_RULE
    PN_maximum_number_of,
47
    PN_string, // special node for non-interned string
48
    PN_bytes, // special node for non-interned bytes
49
    PN_const_object, // special node for a constant, generic Python object
Damien's avatar
Damien committed
50
51
} pn_kind_t;

52
53
54
55
56
#define NEED_METHOD_TABLE (MICROPY_EMIT_CPYTHON || MICROPY_EMIT_NATIVE)

#if NEED_METHOD_TABLE

// we need a method table to do the lookup for the emitter functions
57
58
#define EMIT(fun) (comp->emit_method_table->fun(comp->emit))
#define EMIT_ARG(fun, ...) (comp->emit_method_table->fun(comp->emit, __VA_ARGS__))
59
60
#define EMIT_LOAD_FAST(qst, local_num) (comp->emit_method_table->load_id.fast(comp->emit, qst, local_num))
#define EMIT_LOAD_GLOBAL(qst) (comp->emit_method_table->load_id.global(comp->emit, qst))
61
62
#define EMIT_INLINE_ASM(fun) (comp->emit_inline_asm_method_table->fun(comp->emit_inline_asm))
#define EMIT_INLINE_ASM_ARG(fun, ...) (comp->emit_inline_asm_method_table->fun(comp->emit_inline_asm, __VA_ARGS__))
Damien's avatar
Damien committed
63

64
65
66
67
68
69
70
71
72
73
#else

// if we only have the bytecode emitter enabled then we can do a direct call to the functions
#define EMIT(fun) (mp_emit_bc_##fun(comp->emit))
#define EMIT_ARG(fun, ...) (mp_emit_bc_##fun(comp->emit, __VA_ARGS__))
#define EMIT_LOAD_FAST(qst, local_num) (mp_emit_bc_load_fast(comp->emit, qst, local_num))
#define EMIT_LOAD_GLOBAL(qst) (mp_emit_bc_load_global(comp->emit, qst))

#endif

74
// elements in this struct are ordered to make it compact
Damien's avatar
Damien committed
75
typedef struct _compiler_t {
76
    qstr source_file;
77

78
79
80
    uint8_t is_repl;
    uint8_t pass; // holds enum type pass_kind_t
    uint8_t func_arg_is_super; // used to compile special case of super() function call
81
82
83
84
85
    uint8_t have_star;

    // try to keep compiler clean from nlr
    // this is set to an exception object if we have a compile error
    mp_obj_t compile_error;
Damien's avatar
Damien committed
86

87
    uint next_label;
88

89
90
91
    uint16_t num_dict_params;
    uint16_t num_default_params;

92
93
    uint16_t break_label; // highest bit set indicates we are breaking out of a for loop
    uint16_t continue_label;
94
    uint16_t cur_except_level; // increased for SETUP_EXCEPT, SETUP_FINALLY; decreased for POP_BLOCK, POP_EXCEPT
95
    uint16_t break_continue_except_level;
Damien's avatar
Damien committed
96
97
98
99

    scope_t *scope_head;
    scope_t *scope_cur;

100
    emit_t *emit;                                   // current emitter
101
    #if NEED_METHOD_TABLE
102
    const emit_method_table_t *emit_method_table;   // current emit method table
103
    #endif
104

105
    #if MICROPY_EMIT_INLINE_THUMB
106
107
    emit_inline_asm_t *emit_inline_asm;                                   // current emitter for inline asm
    const emit_inline_asm_method_table_t *emit_inline_asm_method_table;   // current emit method table for inline asm
108
    #endif
Damien's avatar
Damien committed
109
110
} compiler_t;

111
STATIC void compile_syntax_error(compiler_t *comp, mp_parse_node_t pn, const char *msg) {
112
113
    mp_obj_t exc = mp_obj_new_exception_msg(&mp_type_SyntaxError, msg);
    // we don't have a 'block' name, so just pass the NULL qstr to indicate this
114
    if (MP_PARSE_NODE_IS_STRUCT(pn)) {
115
        mp_obj_exception_add_traceback(exc, comp->source_file, (mp_uint_t)((mp_parse_node_struct_t*)pn)->source_line, comp->scope_cur->simple_name);
116
    } else {
117
        // we don't have a line number, so just pass 0
118
        mp_obj_exception_add_traceback(exc, comp->source_file, 0, comp->scope_cur->simple_name);
119
    }
120
    comp->compile_error = exc;
121
122
}

123
#if MICROPY_COMP_MODULE_CONST
124
STATIC const mp_map_elem_t mp_constants_table[] = {
125
126
127
    #if MICROPY_PY_UCTYPES
    { MP_OBJ_NEW_QSTR(MP_QSTR_uctypes), (mp_obj_t)&mp_module_uctypes },
    #endif
128
    // Extra constants as defined by a port
129
    MICROPY_PORT_CONSTANTS
130
};
131
132
STATIC MP_DEFINE_CONST_MAP(mp_constants_map, mp_constants_table);
#endif
133

134
135
136
137
// this function is essentially a simple preprocessor
STATIC mp_parse_node_t fold_constants(compiler_t *comp, mp_parse_node_t pn, mp_map_t *consts) {
    if (0) {
        // dummy
138
#if MICROPY_COMP_CONST
139
140
141
142
143
144
145
146
147
    } else if (MP_PARSE_NODE_IS_ID(pn)) {
        // lookup identifier in table of dynamic constants
        qstr qst = MP_PARSE_NODE_LEAF_ARG(pn);
        mp_map_elem_t *elem = mp_map_lookup(consts, MP_OBJ_NEW_QSTR(qst), MP_MAP_LOOKUP);
        if (elem != NULL) {
            pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, MP_OBJ_SMALL_INT_VALUE(elem->value));
        }
#endif
    } else if (MP_PARSE_NODE_IS_STRUCT(pn)) {
148
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
Damien's avatar
Damien committed
149

150
151
        // fold some parse nodes before folding their arguments
        switch (MP_PARSE_NODE_STRUCT_KIND(pns)) {
152
#if MICROPY_COMP_CONST
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
            case PN_expr_stmt:
                if (!MP_PARSE_NODE_IS_NULL(pns->nodes[1])) {
                    mp_parse_node_struct_t *pns1 = (mp_parse_node_struct_t*)pns->nodes[1];
                    if (MP_PARSE_NODE_STRUCT_KIND(pns1) == PN_expr_stmt_assign) {
                        if (MP_PARSE_NODE_IS_ID(pns->nodes[0])
                            && MP_PARSE_NODE_IS_STRUCT_KIND(pns1->nodes[0], PN_power)
                            && MP_PARSE_NODE_IS_ID(((mp_parse_node_struct_t*)pns1->nodes[0])->nodes[0])
                            && MP_PARSE_NODE_LEAF_ARG(((mp_parse_node_struct_t*)pns1->nodes[0])->nodes[0]) == MP_QSTR_const
                            && MP_PARSE_NODE_IS_STRUCT_KIND(((mp_parse_node_struct_t*)pns1->nodes[0])->nodes[1], PN_trailer_paren)
                            && MP_PARSE_NODE_IS_NULL(((mp_parse_node_struct_t*)pns1->nodes[0])->nodes[2])
                            ) {
                            // code to assign dynamic constants: id = const(value)

                            // get the id
                            qstr id_qstr = MP_PARSE_NODE_LEAF_ARG(pns->nodes[0]);

                            // get the value
                            mp_parse_node_t pn_value = ((mp_parse_node_struct_t*)((mp_parse_node_struct_t*)pns1->nodes[0])->nodes[1])->nodes[0];
                            pn_value = fold_constants(comp, pn_value, consts);
                            if (!MP_PARSE_NODE_IS_SMALL_INT(pn_value)) {
                                compile_syntax_error(comp, (mp_parse_node_t)pns, "constant must be an integer");
                                break;
                            }
176
                            mp_int_t value = MP_PARSE_NODE_LEAF_SMALL_INT(pn_value);
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195

                            // store the value in the table of dynamic constants
                            mp_map_elem_t *elem = mp_map_lookup(consts, MP_OBJ_NEW_QSTR(id_qstr), MP_MAP_LOOKUP_ADD_IF_NOT_FOUND);
                            if (elem->value != MP_OBJ_NULL) {
                                compile_syntax_error(comp, (mp_parse_node_t)pns, "constant redefined");
                                break;
                            }
                            elem->value = MP_OBJ_NEW_SMALL_INT(value);

                            // replace const(value) with value
                            pns1->nodes[0] = pn_value;

                            // finished folding this assignment
                            return pn;
                        }
                    }
                }
                break;
#endif
196
            case PN_string:
197
            case PN_bytes:
198
            case PN_const_object:
199
                return pn;
200
201
202
203
        }

        // fold arguments
        int n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
Damien's avatar
Damien committed
204
        for (int i = 0; i < n; i++) {
205
            pns->nodes[i] = fold_constants(comp, pns->nodes[i], consts);
Damien's avatar
Damien committed
206
207
        }

208
        // try to fold this parse node
209
        switch (MP_PARSE_NODE_STRUCT_KIND(pns)) {
210
211
212
213
214
215
216
217
218
219
            case PN_atom_paren:
                if (n == 1 && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0])) {
                    // (int)
                    pn = pns->nodes[0];
                }
                break;

            case PN_expr:
                if (n == 2 && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[1])) {
                    // int | int
220
221
                    mp_int_t arg0 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[0]);
                    mp_int_t arg1 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[1]);
222
223
224
225
226
227
228
                    pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg0 | arg1);
                }
                break;

            case PN_and_expr:
                if (n == 2 && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[1])) {
                    // int & int
229
230
                    mp_int_t arg0 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[0]);
                    mp_int_t arg1 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[1]);
231
232
233
234
                    pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg0 & arg1);
                }
                break;

Damien's avatar
Damien committed
235
            case PN_shift_expr:
236
                if (n == 3 && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[2])) {
237
238
                    mp_int_t arg0 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[0]);
                    mp_int_t arg1 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[2]);
239
                    if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_DBL_LESS)) {
240
                        // int << int
241
                        if (!(arg1 >= (mp_int_t)BITS_PER_WORD || arg0 > (MP_SMALL_INT_MAX >> arg1) || arg0 < (MP_SMALL_INT_MIN >> arg1))) {
242
243
                            pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg0 << arg1);
                        }
244
245
                    } else {
                        assert(MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_DBL_MORE)); // should be
246
                        // int >> int
247
                        if (arg1 >= (mp_int_t)BITS_PER_WORD) {
248
249
250
251
                            // Shifting to big amounts is underfined behavior
                            // in C and is CPU-dependent; propagate sign bit.
                            arg1 = BITS_PER_WORD - 1;
                        }
252
                        pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg0 >> arg1);
Damien's avatar
Damien committed
253
254
255
256
257
                    }
                }
                break;

            case PN_arith_expr:
258
                // overflow checking here relies on SMALL_INT being strictly smaller than mp_int_t
259
                if (n == 3 && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[2])) {
260
261
                    mp_int_t arg0 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[0]);
                    mp_int_t arg1 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[2]);
262
                    if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_PLUS)) {
263
                        // int + int
264
                        arg0 += arg1;
265
266
                    } else {
                        assert(MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_MINUS)); // should be
267
                        // int - int
268
                        arg0 -= arg1;
269
                    }
270
                    if (MP_SMALL_INT_FITS(arg0)) {
271
                        pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg0);
Damien's avatar
Damien committed
272
273
274
275
276
                    }
                }
                break;

            case PN_term:
277
                if (n == 3 && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[2])) {
278
279
                    mp_int_t arg0 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[0]);
                    mp_int_t arg1 = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[2]);
280
                    if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_STAR)) {
281
                        // int * int
282
283
                        if (!mp_small_int_mul_overflow(arg0, arg1)) {
                            arg0 *= arg1;
284
                            if (MP_SMALL_INT_FITS(arg0)) {
285
286
287
                                pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg0);
                            }
                        }
288
                    } else if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_SLASH)) {
289
290
                        // int / int
                        // pass
291
                    } else if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_PERCENT)) {
292
                        // int%int
293
                        pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, mp_small_int_modulo(arg0, arg1));
294
295
                    } else {
                        assert(MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[1], MP_TOKEN_OP_DBL_SLASH)); // should be
296
                        if (arg1 != 0) {
297
                            // int // int
298
                            pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, mp_small_int_floor_divide(arg0, arg1));
299
                        }
Damien's avatar
Damien committed
300
301
302
303
304
                    }
                }
                break;

            case PN_factor_2:
305
                if (MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[1])) {
306
                    mp_int_t arg = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[1]);
307
                    if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[0], MP_TOKEN_OP_PLUS)) {
308
                        // +int
309
310
                        pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, arg);
                    } else if (MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[0], MP_TOKEN_OP_MINUS)) {
311
                        // -int
312
                        pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, -arg);
313
314
                    } else {
                        assert(MP_PARSE_NODE_IS_TOKEN_KIND(pns->nodes[0], MP_TOKEN_OP_TILDE)); // should be
315
                        // ~int
316
                        pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, ~arg);
Damien's avatar
Damien committed
317
318
319
320
321
                    }
                }
                break;

            case PN_power:
322
323
324
                if (0) {
#if MICROPY_EMIT_CPYTHON
                } else if (MP_PARSE_NODE_IS_SMALL_INT(pns->nodes[0]) && MP_PARSE_NODE_IS_NULL(pns->nodes[1]) && !MP_PARSE_NODE_IS_NULL(pns->nodes[2])) {
325
                    // int ** x
326
                    // can overflow; enabled only to compare with CPython
327
                    mp_parse_node_struct_t *pns2 = (mp_parse_node_struct_t*)pns->nodes[2];
328
                    if (MP_PARSE_NODE_IS_SMALL_INT(pns2->nodes[0])) {
329
                        int power = MP_PARSE_NODE_LEAF_SMALL_INT(pns2->nodes[0]);
Damien's avatar
Damien committed
330
331
                        if (power >= 0) {
                            int ans = 1;
332
                            int base = MP_PARSE_NODE_LEAF_SMALL_INT(pns->nodes[0]);
Damien's avatar
Damien committed
333
334
335
                            for (; power > 0; power--) {
                                ans *= base;
                            }
336
                            pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, ans);
Damien's avatar
Damien committed
337
338
                        }
                    }
339
#endif
340
#if MICROPY_COMP_MODULE_CONST
341
342
343
                } else if (MP_PARSE_NODE_IS_ID(pns->nodes[0]) && MP_PARSE_NODE_IS_STRUCT_KIND(pns->nodes[1], PN_trailer_period) && MP_PARSE_NODE_IS_NULL(pns->nodes[2])) {
                    // id.id
                    // look it up in constant table, see if it can be replaced with an integer
344
                    mp_parse_node_struct_t *pns1 = (mp_parse_node_struct_t*)pns->nodes[1];
345
346
347
348
349
350
351
352
                    assert(MP_PARSE_NODE_IS_ID(pns1->nodes[0]));
                    qstr q_base = MP_PARSE_NODE_LEAF_ARG(pns->nodes[0]);
                    qstr q_attr = MP_PARSE_NODE_LEAF_ARG(pns1->nodes[0]);
                    mp_map_elem_t *elem = mp_map_lookup((mp_map_t*)&mp_constants_map, MP_OBJ_NEW_QSTR(q_base), MP_MAP_LOOKUP);
                    if (elem != NULL) {
                        mp_obj_t dest[2];
                        mp_load_method_maybe(elem->value, q_attr, dest);
                        if (MP_OBJ_IS_SMALL_INT(dest[0]) && dest[1] == NULL) {
353
                            mp_int_t val = MP_OBJ_SMALL_INT_VALUE(dest[0]);
354
                            pn = mp_parse_node_new_leaf(MP_PARSE_NODE_SMALL_INT, val);
355
356
                        }
                    }
357
#endif
Damien's avatar
Damien committed
358
359
360
361
362
363
364
365
                }
                break;
        }
    }

    return pn;
}

366
STATIC void compile_trailer_paren_helper(compiler_t *comp, mp_parse_node_t pn_arglist, bool is_method_call, int n_positional_extra);
367
STATIC void compile_comprehension(compiler_t *comp, mp_parse_node_struct_t *pns, scope_kind_t kind);
368
STATIC void compile_node(compiler_t *comp, mp_parse_node_t pn);
Damien's avatar
Damien committed
369

370
STATIC uint comp_next_label(compiler_t *comp) {
371
372
373
    return comp->next_label++;
}

374
375
376
377
378
379
380
381
382
383
384
385
STATIC void compile_increase_except_level(compiler_t *comp) {
    comp->cur_except_level += 1;
    if (comp->cur_except_level > comp->scope_cur->exc_stack_size) {
        comp->scope_cur->exc_stack_size = comp->cur_except_level;
    }
}

STATIC void compile_decrease_except_level(compiler_t *comp) {
    assert(comp->cur_except_level > 0);
    comp->cur_except_level -= 1;
}

386
STATIC scope_t *scope_new_and_link(compiler_t *comp, scope_kind_t kind, mp_parse_node_t pn, uint emit_options) {
387
    scope_t *scope = scope_new(kind, pn, comp->source_file, emit_options);
Damien's avatar
Damien committed
388
389
390
391
392
393
394
395
396
397
398
399
400
401
    scope->parent = comp->scope_cur;
    scope->next = NULL;
    if (comp->scope_head == NULL) {
        comp->scope_head = scope;
    } else {
        scope_t *s = comp->scope_head;
        while (s->next != NULL) {
            s = s->next;
        }
        s->next = scope;
    }
    return scope;
}

402
403
404
typedef void (*apply_list_fun_t)(compiler_t *comp, mp_parse_node_t pn);

STATIC void apply_to_single_or_list(compiler_t *comp, mp_parse_node_t pn, pn_kind_t pn_list_kind, apply_list_fun_t f) {
405
    if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, pn_list_kind)) {
406
407
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
        int num_nodes = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
Damien's avatar
Damien committed
408
409
410
        for (int i = 0; i < num_nodes; i++) {
            f(comp, pns->nodes[i]);
        }
411
    } else if (!MP_PARSE_NODE_IS_NULL(pn)) {
Damien's avatar
Damien committed
412
413
414
415
        f(comp, pn);
    }
}

416
STATIC void compile_generic_all_nodes(compiler_t *comp, mp_parse_node_struct_t *pns) {
417
    int num_nodes = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
Damien's avatar
Damien committed
418
419
420
421
422
    for (int i = 0; i < num_nodes; i++) {
        compile_node(comp, pns->nodes[i]);
    }
}

423
424
425
426
STATIC void compile_load_id(compiler_t *comp, qstr qst) {
    if (comp->pass == MP_PASS_SCOPE) {
        mp_emit_common_get_id_for_load(comp->scope_cur, qst);
    } else {
427
        #if NEED_METHOD_TABLE
428
        mp_emit_common_id_op(comp->emit, &comp->emit_method_table->load_id, comp->scope_cur, qst);
429
430
431
        #else
        mp_emit_common_id_op(comp->emit, &mp_emit_bc_method_table_load_id_ops, comp->scope_cur, qst);
        #endif
432
433
434
435
436
437
438
    }
}

STATIC void compile_store_id(compiler_t *comp, qstr qst) {
    if (comp->pass == MP_PASS_SCOPE) {
        mp_emit_common_get_id_for_modification(comp->scope_cur, qst);
    } else {
439
        #if NEED_METHOD_TABLE
440
        mp_emit_common_id_op(comp->emit, &comp->emit_method_table->store_id, comp->scope_cur, qst);
441
442
443
        #else
        mp_emit_common_id_op(comp->emit, &mp_emit_bc_method_table_store_id_ops, comp->scope_cur, qst);
        #endif
444
445
446
447
448
449
450
    }
}

STATIC void compile_delete_id(compiler_t *comp, qstr qst) {
    if (comp->pass == MP_PASS_SCOPE) {
        mp_emit_common_get_id_for_modification(comp->scope_cur, qst);
    } else {
451
        #if NEED_METHOD_TABLE
452
        mp_emit_common_id_op(comp->emit, &comp->emit_method_table->delete_id, comp->scope_cur, qst);
453
454
455
        #else
        mp_emit_common_id_op(comp->emit, &mp_emit_bc_method_table_delete_id_ops, comp->scope_cur, qst);
        #endif
456
457
458
    }
}

459
#if MICROPY_EMIT_CPYTHON
460
STATIC bool cpython_c_tuple_is_const(mp_parse_node_t pn) {
461
462
463
    if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_string)) {
        return true;
    }
464
465
466
    if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_bytes)) {
        return true;
    }
467
468
469
    if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_const_object)) {
        return true;
    }
470
    if (!MP_PARSE_NODE_IS_LEAF(pn)) {
Damien's avatar
Damien committed
471
472
        return false;
    }
473
    if (MP_PARSE_NODE_IS_ID(pn)) {
Damien's avatar
Damien committed
474
475
476
477
478
        return false;
    }
    return true;
}

479
STATIC void cpython_c_print_quoted_str(vstr_t *vstr, const char *str, uint len, bool bytes) {
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
    bool has_single_quote = false;
    bool has_double_quote = false;
    for (int i = 0; i < len; i++) {
        if (str[i] == '\'') {
            has_single_quote = true;
        } else if (str[i] == '"') {
            has_double_quote = true;
        }
    }
    if (bytes) {
        vstr_printf(vstr, "b");
    }
    bool quote_single = false;
    if (has_single_quote && !has_double_quote) {
        vstr_printf(vstr, "\"");
    } else {
        quote_single = true;
        vstr_printf(vstr, "'");
    }
    for (int i = 0; i < len; i++) {
        if (str[i] == '\n') {
            vstr_printf(vstr, "\\n");
        } else if (str[i] == '\\') {
            vstr_printf(vstr, "\\\\");
        } else if (str[i] == '\'' && quote_single) {
            vstr_printf(vstr, "\\'");
        } else {
            vstr_printf(vstr, "%c", str[i]);
        }
    }
    if (has_single_quote && !has_double_quote) {
        vstr_printf(vstr, "\"");
    } else {
        vstr_printf(vstr, "'");
    }
}

517
STATIC void cpython_c_tuple_emit_const(compiler_t *comp, mp_parse_node_t pn, vstr_t *vstr) {
518
    if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_string) || MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_bytes)) {
519
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
520
        cpython_c_print_quoted_str(vstr, (const char*)pns->nodes[0], (mp_uint_t)pns->nodes[1], MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_bytes));
521
522
523
        return;
    }

524
525
526
527
528
529
    if (MP_PARSE_NODE_IS_STRUCT_KIND(pn, PN_const_object)) {
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
        mp_obj_print((mp_obj_t)pns->nodes[0], PRINT_REPR);
        return;
    }

530
    assert(MP_PARSE_NODE_IS_LEAF(pn));
531
532
533
534
535
    if (MP_PARSE_NODE_IS_SMALL_INT(pn)) {
        vstr_printf(vstr, INT_FMT, MP_PARSE_NODE_LEAF_SMALL_INT(pn));
        return;
    }

536
    mp_uint_t arg = MP_PARSE_NODE_LEAF_ARG(pn);
537
538
    switch (MP_PARSE_NODE_LEAF_KIND(pn)) {
        case MP_PARSE_NODE_ID: assert(0);
539
540
        case MP_PARSE_NODE_STRING:
        case MP_PARSE_NODE_BYTES: {
541
            mp_uint_t len;
542
543
544
545
            const byte *str = qstr_data(arg, &len);
            cpython_c_print_quoted_str(vstr, (const char*)str, len, MP_PARSE_NODE_LEAF_KIND(pn) == MP_PARSE_NODE_BYTES);
            break;
        }
546
        case MP_PARSE_NODE_TOKEN:
Damien's avatar
Damien committed
547
            switch (arg) {
548
549
550
                case MP_TOKEN_KW_FALSE: vstr_printf(vstr, "False"); break;
                case MP_TOKEN_KW_NONE: vstr_printf(vstr, "None"); break;
                case MP_TOKEN_KW_TRUE: vstr_printf(vstr, "True"); break;
551
                default: assert(0); // shouldn't happen
Damien's avatar
Damien committed
552
553
554
555
556
557
            }
            break;
        default: assert(0);
    }
}

558
STATIC void cpython_c_tuple(compiler_t *comp, mp_parse_node_t pn, mp_parse_node_struct_t *pns_list) {
Damien's avatar
Damien committed
559
560
    int n = 0;
    if (pns_list != NULL) {
561
        n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns_list);
Damien's avatar
Damien committed
562
563
564
    }
    int total = n;
    bool is_const = true;
565
    if (!MP_PARSE_NODE_IS_NULL(pn)) {
Damien's avatar
Damien committed
566
        total += 1;
567
        if (!cpython_c_tuple_is_const(pn)) {
Damien's avatar
Damien committed
568
569
570
571
            is_const = false;
        }
    }
    for (int i = 0; i < n; i++) {
572
        if (!cpython_c_tuple_is_const(pns_list->nodes[i])) {
Damien's avatar
Damien committed
573
574
575
576
577
578
            is_const = false;
            break;
        }
    }
    if (total > 0 && is_const) {
        bool need_comma = false;
579
580
        vstr_t *vstr = vstr_new();
        vstr_printf(vstr, "(");
581
        if (!MP_PARSE_NODE_IS_NULL(pn)) {
582
            cpython_c_tuple_emit_const(comp, pn, vstr);
Damien's avatar
Damien committed
583
584
585
586
            need_comma = true;
        }
        for (int i = 0; i < n; i++) {
            if (need_comma) {
587
                vstr_printf(vstr, ", ");
Damien's avatar
Damien committed
588
            }
589
            cpython_c_tuple_emit_const(comp, pns_list->nodes[i], vstr);
Damien's avatar
Damien committed
590
591
592
            need_comma = true;
        }
        if (total == 1) {
593
            vstr_printf(vstr, ",)");
Damien's avatar
Damien committed
594
        } else {
595
            vstr_printf(vstr, ")");
Damien's avatar
Damien committed
596
        }
597
        EMIT_ARG(load_const_verbatim_strn, vstr_str(vstr), vstr_len(vstr));
598
        vstr_free(vstr);
Damien's avatar
Damien committed
599
    } else {
600
        if (!MP_PARSE_NODE_IS_NULL(pn)) {
Damien's avatar
Damien committed
601
602
603
604
605
            compile_node(comp, pn);
        }
        for (int i = 0; i < n; i++) {
            compile_node(comp, pns_list->nodes[i]);
        }
606
        EMIT_ARG(build_tuple, total);
Damien's avatar
Damien committed
607
608
    }
}
609
610
611
#endif

// funnelling all tuple creations through this function is purely so we can optionally agree with CPython
612
STATIC void c_tuple(compiler_t *comp, mp_parse_node_t pn, mp_parse_node_struct_t *pns_list) {
613
#if MICROPY_EMIT_CPYTHON
614
615
616
    cpython_c_tuple(comp, pn, pns_list);
#else
    int total = 0;
617
    if (!MP_PARSE_NODE_IS_NULL(pn)) {
618
619
620
621
        compile_node(comp, pn);
        total += 1;
    }
    if (pns_list != NULL) {
622
        int n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns_list);
623
624
625
626
627
        for (int i = 0; i < n; i++) {
            compile_node(comp, pns_list->nodes[i]);
        }
        total += n;
    }
628
    EMIT_ARG(build_tuple, total);
629
630
#endif
}
Damien's avatar
Damien committed
631

632
STATIC void compile_generic_tuple(compiler_t *comp, mp_parse_node_struct_t *pns) {
Damien's avatar
Damien committed
633
    // a simple tuple expression
634
    c_tuple(comp, MP_PARSE_NODE_NULL, pns);
Damien's avatar
Damien committed
635
636
}

637
STATIC bool node_is_const_false(mp_parse_node_t pn) {
638
639
    return MP_PARSE_NODE_IS_TOKEN_KIND(pn, MP_TOKEN_KW_FALSE)
        || (MP_PARSE_NODE_IS_SMALL_INT(pn) && MP_PARSE_NODE_LEAF_SMALL_INT(pn) == 0);
Damien's avatar
Damien committed
640
641
}

642
STATIC bool node_is_const_true(mp_parse_node_t pn) {
643
644
    return MP_PARSE_NODE_IS_TOKEN_KIND(pn, MP_TOKEN_KW_TRUE)
        || (MP_PARSE_NODE_IS_SMALL_INT(pn) && MP_PARSE_NODE_LEAF_SMALL_INT(pn) != 0);
Damien's avatar
Damien committed
645
646
}

647
#if MICROPY_EMIT_CPYTHON
648
// the is_nested variable is purely to match with CPython, which doesn't fully optimise not's
649
STATIC void cpython_c_if_cond(compiler_t *comp, mp_parse_node_t pn, bool jump_if, int label, bool is_nested) {
Damien's avatar
Damien committed
650
651
    if (node_is_const_false(pn)) {
        if (jump_if == false) {
652
            EMIT_ARG(jump, label);
Damien's avatar
Damien committed
653
654
655
656
        }
        return;
    } else if (node_is_const_true(pn)) {
        if (jump_if == true) {
657
            EMIT_ARG(jump, label);
Damien's avatar
Damien committed
658
659
        }
        return;
660
661
662
663
    } else if (MP_PARSE_NODE_IS_STRUCT(pn)) {
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
        int n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
        if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_or_test) {
Damien's avatar
Damien committed
664
            if (jump_if == false) {
665
                uint label2 = comp_next_label(comp);
Damien's avatar
Damien committed
666
                for (int i = 0; i < n - 1; i++) {
667
                    cpython_c_if_cond(comp, pns->nodes[i], true, label2, true);
Damien's avatar
Damien committed
668
                }
669
                cpython_c_if_cond(comp, pns->nodes[n - 1], false, label, true);
670
                EMIT_ARG(label_assign, label2);
Damien's avatar
Damien committed
671
672
            } else {
                for (int i = 0; i < n; i++) {
673
                    cpython_c_if_cond(comp, pns->nodes[i], true, label, true);
Damien's avatar
Damien committed
674
675
676
                }
            }
            return;
677
        } else if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_and_test) {
Damien's avatar
Damien committed
678
679
            if (jump_if == false) {
                for (int i = 0; i < n; i++) {
680
                    cpython_c_if_cond(comp, pns->nodes[i], false, label, true);
Damien's avatar
Damien committed
681
682
                }
            } else {
683
                uint label2 = comp_next_label(comp);
Damien's avatar
Damien committed
684
                for (int i = 0; i < n - 1; i++) {
685
                    cpython_c_if_cond(comp, pns->nodes[i], false, label2, true);
Damien's avatar
Damien committed
686
                }
687
                cpython_c_if_cond(comp, pns->nodes[n - 1], true, label, true);
688
                EMIT_ARG(label_assign, label2);
Damien's avatar
Damien committed
689
690
            }
            return;
691
        } else if (!is_nested && MP_PARSE_NODE_STRUCT_KIND(pns) == PN_not_test_2) {
692
            cpython_c_if_cond(comp, pns->nodes[0], !jump_if, label, true);
Damien's avatar
Damien committed
693
694
695
696
697
698
            return;
        }
    }

    // nothing special, fall back to default compiling for node and jump
    compile_node(comp, pn);
699
    EMIT_ARG(pop_jump_if, jump_if, label);
Damien's avatar
Damien committed
700
}
701
#endif
Damien's avatar
Damien committed
702

703
STATIC void c_if_cond(compiler_t *comp, mp_parse_node_t pn, bool jump_if, int label) {
704
#if MICROPY_EMIT_CPYTHON
705
706
707
708
    cpython_c_if_cond(comp, pn, jump_if, label, false);
#else
    if (node_is_const_false(pn)) {
        if (jump_if == false) {
709
            EMIT_ARG(jump, label);
710
711
712
713
        }
        return;
    } else if (node_is_const_true(pn)) {
        if (jump_if == true) {
714
            EMIT_ARG(jump, label);
715
716
        }
        return;
717
718
719
720
    } else if (MP_PARSE_NODE_IS_STRUCT(pn)) {
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
        int n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns);
        if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_or_test) {
721
            if (jump_if == false) {
722
            and_or_logic1:;
723
                uint label2 = comp_next_label(comp);
724
                for (int i = 0; i < n - 1; i++) {
725
                    c_if_cond(comp, pns->nodes[i], !jump_if, label2);
726
                }
727
                c_if_cond(comp, pns->nodes[n - 1], jump_if, label);
728
                EMIT_ARG(label_assign, label2);
729
            } else {
730
            and_or_logic2:
731
                for (int i = 0; i < n; i++) {
732
                    c_if_cond(comp, pns->nodes[i], jump_if, label);
733
734
735
                }
            }
            return;
736
        } else if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_and_test) {
737
            if (jump_if == false) {
738
                goto and_or_logic2;
739
            } else {
740
                goto and_or_logic1;
741
            }
742
        } else if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_not_test_2) {
743
744
            c_if_cond(comp, pns->nodes[0], !jump_if, label);
            return;
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
        } else if (MP_PARSE_NODE_STRUCT_KIND(pns) == PN_atom_paren) {
            // cond is something in parenthesis
            if (MP_PARSE_NODE_IS_NULL(pns->nodes[0])) {
                // empty tuple, acts as false for the condition
                if (jump_if == false) {
                    EMIT_ARG(jump, label);
                }
            } else if (MP_PARSE_NODE_IS_STRUCT_KIND(pns->nodes[0], PN_testlist_comp)) {
                // non-empty tuple, acts as true for the condition
                if (jump_if == true) {
                    EMIT_ARG(jump, label);
                }
            } else {
                // parenthesis around 1 item, is just that item
                c_if_cond(comp, pns->nodes[0], jump_if, label);
            }
            return;
762
763
764
765
766
        }
    }

    // nothing special, fall back to default compiling for node and jump
    compile_node(comp, pn);
767
    EMIT_ARG(pop_jump_if, jump_if, label);
768
#endif
Damien's avatar
Damien committed
769
770
771
}

typedef enum { ASSIGN_STORE, ASSIGN_AUG_LOAD, ASSIGN_AUG_STORE } assign_kind_t;
772
STATIC void c_assign(compiler_t *comp, mp_parse_node_t pn, assign_kind_t kind);
Damien's avatar
Damien committed
773

774
STATIC void c_assign_power(compiler_t *comp, mp_parse_node_struct_t *pns, assign_kind_t assign_kind) {
Damien's avatar
Damien committed
775
776
777
778
    if (assign_kind != ASSIGN_AUG_STORE) {
        compile_node(comp, pns->nodes[0]);
    }

779
780
781
782
    if (MP_PARSE_NODE_IS_STRUCT(pns->nodes[1])) {
        mp_parse_node_struct_t *pns1 = (mp_parse_node_struct_t*)pns->nodes[1];
        if (MP_PARSE_NODE_STRUCT_KIND(pns1) == PN_power_trailers) {
            int n = MP_PARSE_NODE_STRUCT_NUM_NODES(pns1);
Damien's avatar
Damien committed
783
784
785
786
787
            if (assign_kind != ASSIGN_AUG_STORE) {
                for (int i = 0; i < n - 1; i++) {
                    compile_node(comp, pns1->nodes[i]);
                }
            }
788
789
            assert(MP_PARSE_NODE_IS_STRUCT(pns1->nodes[n - 1]));
            pns1 = (mp_parse_node_struct_t*)pns1->nodes[n - 1];
Damien's avatar
Damien committed
790
        }
791
        if (MP_PARSE_NODE_STRUCT_KIND(pns1) == PN_trailer_bracket) {
Damien's avatar
Damien committed
792
793
794
795
796
797
798
            if (assign_kind == ASSIGN_AUG_STORE) {
                EMIT(rot_three);
                EMIT(store_subscr);
            } else {
                compile_node(comp, pns1->nodes[0]);
                if (assign_kind == ASSIGN_AUG_LOAD) {
                    EMIT(dup_top_two);
799
                    EMIT(load_subscr);
Damien's avatar
Damien committed
800
801
802
803
                } else {
                    EMIT(store_subscr);
                }
            }
804
805
        } else if (MP_PARSE_NODE_STRUCT_KIND(pns1) == PN_trailer_period) {
            assert(MP_PARSE_NODE_IS_ID(pns1->nodes[0]));
Damien's avatar
Damien committed
806
807
            if (assign_kind == ASSIGN_AUG_LOAD) {
                EMIT(dup_top);
808
                EMIT_ARG(load_attr, MP_PARSE_NODE_LEAF_ARG(pns1->nodes[0]));
Damien's avatar
Damien committed
809
810
811
812
            } else {
                if (assign_kind == ASSIGN_AUG_STORE) {
                    EMIT(rot_two);
                }
813
                EMIT_ARG(store_attr, MP_PARSE_NODE_LEAF_ARG(pns1->nodes[0]));
Damien's avatar
Damien committed
814
815
            }
        } else {
816
            goto cannot_assign;
Damien's avatar
Damien committed
817
818
        }
    } else {
819
        goto cannot_assign;
Damien's avatar
Damien committed
820
821
    }

822
    if (!MP_PARSE_NODE_IS_NULL(pns->nodes[2])) {
823
        goto cannot_assign;
Damien's avatar
Damien committed
824
    }
825
826
827
828
829

    return;

cannot_assign:
    compile_syntax_error(comp, (mp_parse_node_t)pns, "can't assign to expression");
Damien's avatar
Damien committed
830
831
}

832
// we need to allow for a caller passing in 1 initial node (node_head) followed by an array of nodes (nodes_tail)
833
STATIC void c_assign_tuple(compiler_t *comp, mp_parse_node_t node_head, uint num_tail, mp_parse_node_t *nodes_tail) {
834
835
836
    uint num_head = (node_head == MP_PARSE_NODE_NULL) ? 0 : 1;

    // look for star expression
837
    uint have_star_index = -1;
838
839
840
841
    if (num_head != 0 && MP_PARSE_NODE_IS_STRUCT_KIND(node_head, PN_star_expr)) {
        EMIT_ARG(unpack_ex, 0, num_tail);
        have_star_index = 0;
    }
842
    for (uint i = 0; i < num_tail; i++) {
843
        if (MP_PARSE_NODE_IS_STRUCT_KIND(nodes_tail[i], PN_star_expr)) {
844
            if (have_star_index == (uint)-1) {
845
846
                EMIT_ARG(unpack_ex, num_head + i, num_tail - i - 1);
                have_star_index = num_head + i;
Damien's avatar
Damien committed
847
            } else {
848
                compile_syntax_error(comp, nodes_tail[i], "multiple *x in assignment");
Damien's avatar
Damien committed
849
850
851
852
                return;
            }
        }
    }
853
    if (have_star_index == (uint)-1) {
854
        EMIT_ARG(unpack_sequence, num_head + num_tail);
Damien's avatar
Damien committed
855
    }
856
857
858
    if (num_head != 0) {
        if (0 == have_star_index) {
            c_assign(comp, ((mp_parse_node_struct_t*)node_head)->nodes[0], ASSIGN_STORE);
Damien's avatar
Damien committed
859
        } else {
860
861
862
            c_assign(comp, node_head, ASSIGN_STORE);
        }
    }
863
    for (uint i = 0; i < num_tail; i++) {
864
865
866
867
        if (num_head + i == have_star_index) {
            c_assign(comp, ((mp_parse_node_struct_t*)nodes_tail[i])->nodes[0], ASSIGN_STORE);
        } else {
            c_assign(comp, nodes_tail[i], ASSIGN_STORE);
Damien's avatar
Damien committed
868
869
870
871
872
        }
    }
}

// assigns top of stack to pn
873
STATIC void c_assign(compiler_t *comp, mp_parse_node_t pn, assign_kind_t assign_kind) {
Damien's avatar
Damien committed
874
    tail_recursion:
875
876
    assert(!MP_PARSE_NODE_IS_NULL(pn));
    if (MP_PARSE_NODE_IS_LEAF(pn)) {
877
        if (MP_PARSE_NODE_IS_ID(pn)) {
878
            qstr arg = MP_PARSE_NODE_LEAF_ARG(pn);
Damien's avatar
Damien committed
879
880
881
            switch (assign_kind) {
                case ASSIGN_STORE:
                case ASSIGN_AUG_STORE:
882
                    compile_store_id(comp, arg);
Damien's avatar
Damien committed
883
884
                    break;
                case ASSIGN_AUG_LOAD:
885
                default:
886
                    compile_load_id(comp, arg);
Damien's avatar
Damien committed
887
888
889
                    break;
            }
        } else {
890
            compile_syntax_error(comp, pn, "can't assign to literal");
Damien's avatar
Damien committed
891
892
893
            return;
        }
    } else {
894
        // pn must be a struct
895
896
        mp_parse_node_struct_t *pns = (mp_parse_node_struct_t*)pn;
        switch (MP_PARSE_NODE_STRUCT_KIND(pns)) {
Damien's avatar
Damien committed
897
898
899
900
901
902
903
904
905
906
907
            case PN_power:
                // lhs is an index or attribute
                c_assign_power(comp, pns, assign_kind);
                break;

            case PN_testlist_star_expr:
            case PN_exprlist:
                // lhs is a tuple
                if (assign_kind != ASSIGN_STORE) {
                    goto bad_aug;
                }
908
                c_assign_tuple(comp, MP_PARSE_NODE_NULL, MP_PARSE_NODE_STRUCT_NUM_NODES(pns), pns->nodes);
Damien's avatar
Damien committed
909
910
911
912
                break;

            case PN_atom_paren:
                // lhs is something in parenthesis
913
                if (MP_PARSE_NODE_IS_NULL(pns->nodes[0])) {
Damien's avatar
Damien committed
914
                    // empty tuple
915
                    goto cannot_assign;
916
                } else if (MP_PARSE_NODE_IS_STRUCT_KIND(pns->nodes[0], PN_testlist_comp)) {
917
918
919
                    if (assign_kind != ASSIGN_STORE) {
                        goto bad_aug;
                    }
920
                    pns = (mp_parse_node_struct_t*)pns->nodes[0];
Damien's avatar
Damien committed
921
922
923
924
925
926
927
928
929
930
931
932
933
                    goto testlist_comp;
                } else {
                    // parenthesis around 1 item, is just that item
                    pn = pns->nodes[0];
                    goto tail_recursion;
                }
                break;

            case PN_atom_bracket:
                // lhs is something in brackets
                if (assign_kind != ASSIGN_STORE) {
                    goto bad_aug;
                }
934
                if (MP_PARSE_NODE_IS_NULL(pns->nodes[0])) {
Damien's avatar
Damien committed
935
                    // empty list, assignment allowed
936
                    c_assign_tuple(comp, MP_PARSE_NODE_NULL, 0, NULL);
937
938
                } else if (MP_PARSE_NODE_IS_STRUCT_KIND(pns->nodes[0], PN_testlist_comp)) {
                    pns = (mp_parse_node_struct_t*)pns->nodes[0];
Damien's avatar
Damien committed
939
940
941
                    goto testlist_comp;
                } else {
                    // brackets around 1 item
942
                    c_assign_tuple(comp, pns->nodes[0], 0, NULL);
Damien's avatar
Damien committed
943
944
945
946
                }
                break;

            default:
947
                goto cannot_assign;
Damien's avatar
Damien committed
948
949
950
951
952
        }
        return;

        testlist_comp:
        // lhs is a sequence
953
954
955
        if (MP_PARSE_NODE_IS_STRUCT(pns->nodes[1])) {
            mp_parse_node_struct_t *pns2 = (mp_parse_node_struct_t*)pns->nodes[1];
            if (MP_PARSE_NODE_STRUCT_KIND(pns2) == PN_testlist_comp_3b) {
Damien's avatar
Damien committed
956
                // sequence of one item, with trailing comma
957
                assert(MP_PARSE_NODE_IS_NULL(pns2->nodes[0]));
958
                c_assign_tuple(comp, pns->nodes[0], 0, NULL);
959
            } else if (MP_PARSE_NODE_STRUCT_KIND(pns2) == PN_testlist_comp_3c) {