-
-
Notifications
You must be signed in to change notification settings - Fork 29.2k
/
compile.c
9367 lines (8538 loc) · 282 KB
/
compile.c
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
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
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
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* This file compiles an abstract syntax tree (AST) into Python bytecode.
*
* The primary entry point is _PyAST_Compile(), which returns a
* PyCodeObject. The compiler makes several passes to build the code
* object:
* 1. Checks for future statements. See future.c
* 2. Builds a symbol table. See symtable.c.
* 3. Generate code for basic blocks. See compiler_mod() in this file.
* 4. Assemble the basic blocks into final code. See assemble() in
* this file.
* 5. Optimize the byte code (peephole optimizations).
*
* Note that compiler_mod() suggests module, but the module ast type
* (mod_ty) has cases for expressions and interactive statements.
*
* CAUTION: The VISIT_* macros abort the current function when they
* encounter a problem. So don't invoke them when there is memory
* which needs to be released. Code blocks are OK, as the compiler
* structure takes care of releasing those. Use the arena to manage
* objects.
*/
#include <stdbool.h>
// Need _PyOpcode_RelativeJump of pycore_opcode.h
#define NEED_OPCODE_TABLES
#include "Python.h"
#include "pycore_ast.h" // _PyAST_GetDocString()
#include "pycore_code.h" // _PyCode_New()
#include "pycore_compile.h" // _PyFuture_FromAST()
#include "pycore_long.h" // _PyLong_GetZero()
#include "pycore_opcode.h" // _PyOpcode_Caches
#include "pycore_pymem.h" // _PyMem_IsPtrFreed()
#include "pycore_symtable.h" // PySTEntryObject
#define DEFAULT_BLOCK_SIZE 16
#define DEFAULT_CODE_SIZE 128
#define DEFAULT_LNOTAB_SIZE 16
#define DEFAULT_CNOTAB_SIZE 32
#define COMP_GENEXP 0
#define COMP_LISTCOMP 1
#define COMP_SETCOMP 2
#define COMP_DICTCOMP 3
/* A soft limit for stack use, to avoid excessive
* memory use for large constants, etc.
*
* The value 30 is plucked out of thin air.
* Code that could use more stack than this is
* rare, so the exact value is unimportant.
*/
#define STACK_USE_GUIDELINE 30
/* If we exceed this limit, it should
* be considered a compiler bug.
* Currently it should be impossible
* to exceed STACK_USE_GUIDELINE * 100,
* as 100 is the maximum parse depth.
* For performance reasons we will
* want to reduce this to a
* few hundred in the future.
*
* NOTE: Whatever MAX_ALLOWED_STACK_USE is
* set to, it should never restrict what Python
* we can write, just how we compile it.
*/
#define MAX_ALLOWED_STACK_USE (STACK_USE_GUIDELINE * 100)
/* Pseudo-instructions used in the compiler,
* but turned into NOPs or other instructions
* by the assembler. */
#define SETUP_FINALLY -1
#define SETUP_CLEANUP -2
#define SETUP_WITH -3
#define POP_BLOCK -4
#define JUMP -5
#define JUMP_NO_INTERRUPT -6
#define POP_JUMP_IF_FALSE -7
#define POP_JUMP_IF_TRUE -8
#define POP_JUMP_IF_NONE -9
#define POP_JUMP_IF_NOT_NONE -10
#define MIN_VIRTUAL_OPCODE -10
#define MAX_ALLOWED_OPCODE 254
#define IS_WITHIN_OPCODE_RANGE(opcode) \
((opcode) >= MIN_VIRTUAL_OPCODE && (opcode) <= MAX_ALLOWED_OPCODE)
#define IS_VIRTUAL_OPCODE(opcode) ((opcode) < 0)
#define IS_VIRTUAL_JUMP_OPCODE(opcode) \
((opcode) == JUMP || \
(opcode) == JUMP_NO_INTERRUPT || \
(opcode) == POP_JUMP_IF_NONE || \
(opcode) == POP_JUMP_IF_NOT_NONE || \
(opcode) == POP_JUMP_IF_FALSE || \
(opcode) == POP_JUMP_IF_TRUE)
/* opcodes which are not emitted in codegen stage, only by the assembler */
#define IS_ASSEMBLER_OPCODE(opcode) \
((opcode) == JUMP_FORWARD || \
(opcode) == JUMP_BACKWARD || \
(opcode) == JUMP_BACKWARD_NO_INTERRUPT || \
(opcode) == POP_JUMP_FORWARD_IF_NONE || \
(opcode) == POP_JUMP_BACKWARD_IF_NONE || \
(opcode) == POP_JUMP_FORWARD_IF_NOT_NONE || \
(opcode) == POP_JUMP_BACKWARD_IF_NOT_NONE || \
(opcode) == POP_JUMP_FORWARD_IF_TRUE || \
(opcode) == POP_JUMP_BACKWARD_IF_TRUE || \
(opcode) == POP_JUMP_FORWARD_IF_FALSE || \
(opcode) == POP_JUMP_BACKWARD_IF_FALSE)
#define IS_BACKWARDS_JUMP_OPCODE(opcode) \
((opcode) == JUMP_BACKWARD || \
(opcode) == JUMP_BACKWARD_NO_INTERRUPT || \
(opcode) == POP_JUMP_BACKWARD_IF_NONE || \
(opcode) == POP_JUMP_BACKWARD_IF_NOT_NONE || \
(opcode) == POP_JUMP_BACKWARD_IF_TRUE || \
(opcode) == POP_JUMP_BACKWARD_IF_FALSE)
#define IS_TOP_LEVEL_AWAIT(c) ( \
(c->c_flags->cf_flags & PyCF_ALLOW_TOP_LEVEL_AWAIT) \
&& (c->u->u_ste->ste_type == ModuleBlock))
struct instr {
int i_opcode;
int i_oparg;
/* target block (if jump instruction) */
struct basicblock_ *i_target;
/* target block when exception is raised, should not be set by front-end. */
struct basicblock_ *i_except;
int i_lineno;
int i_end_lineno;
int i_col_offset;
int i_end_col_offset;
};
typedef struct excepthandler {
struct instr *setup;
int offset;
} ExceptHandler;
typedef struct exceptstack {
struct basicblock_ *handlers[CO_MAXBLOCKS+1];
int depth;
} ExceptStack;
#define LOG_BITS_PER_INT 5
#define MASK_LOW_LOG_BITS 31
static inline int
is_bit_set_in_table(const uint32_t *table, int bitindex) {
/* Is the relevant bit set in the relevant word? */
/* 256 bits fit into 8 32-bits words.
* Word is indexed by (bitindex>>ln(size of int in bits)).
* Bit within word is the low bits of bitindex.
*/
if (bitindex >= 0 && bitindex < 256) {
uint32_t word = table[bitindex >> LOG_BITS_PER_INT];
return (word >> (bitindex & MASK_LOW_LOG_BITS)) & 1;
}
else {
return 0;
}
}
static inline int
is_relative_jump(struct instr *i)
{
return is_bit_set_in_table(_PyOpcode_RelativeJump, i->i_opcode);
}
static inline int
is_block_push(struct instr *instr)
{
int opcode = instr->i_opcode;
return opcode == SETUP_FINALLY || opcode == SETUP_WITH || opcode == SETUP_CLEANUP;
}
static inline int
is_jump(struct instr *i)
{
return IS_VIRTUAL_JUMP_OPCODE(i->i_opcode) ||
is_bit_set_in_table(_PyOpcode_Jump, i->i_opcode);
}
static int
instr_size(struct instr *instruction)
{
int opcode = instruction->i_opcode;
assert(!IS_VIRTUAL_OPCODE(opcode));
int oparg = HAS_ARG(opcode) ? instruction->i_oparg : 0;
int extended_args = (0xFFFFFF < oparg) + (0xFFFF < oparg) + (0xFF < oparg);
int caches = _PyOpcode_Caches[opcode];
return extended_args + 1 + caches;
}
static void
write_instr(_Py_CODEUNIT *codestr, struct instr *instruction, int ilen)
{
int opcode = instruction->i_opcode;
assert(!IS_VIRTUAL_OPCODE(opcode));
int oparg = HAS_ARG(opcode) ? instruction->i_oparg : 0;
int caches = _PyOpcode_Caches[opcode];
switch (ilen - caches) {
case 4:
*codestr++ = _Py_MAKECODEUNIT(EXTENDED_ARG_QUICK, (oparg >> 24) & 0xFF);
/* fall through */
case 3:
*codestr++ = _Py_MAKECODEUNIT(EXTENDED_ARG_QUICK, (oparg >> 16) & 0xFF);
/* fall through */
case 2:
*codestr++ = _Py_MAKECODEUNIT(EXTENDED_ARG_QUICK, (oparg >> 8) & 0xFF);
/* fall through */
case 1:
*codestr++ = _Py_MAKECODEUNIT(opcode, oparg & 0xFF);
break;
default:
Py_UNREACHABLE();
}
while (caches--) {
*codestr++ = _Py_MAKECODEUNIT(CACHE, 0);
}
}
typedef struct basicblock_ {
/* Each basicblock in a compilation unit is linked via b_list in the
reverse order that the block are allocated. b_list points to the next
block, not to be confused with b_next, which is next by control flow. */
struct basicblock_ *b_list;
/* Exception stack at start of block, used by assembler to create the exception handling table */
ExceptStack *b_exceptstack;
/* pointer to an array of instructions, initially NULL */
struct instr *b_instr;
/* If b_next is non-NULL, it is a pointer to the next
block reached by normal control flow. */
struct basicblock_ *b_next;
/* number of instructions used */
int b_iused;
/* length of instruction array (b_instr) */
int b_ialloc;
/* Number of predecssors that a block has. */
int b_predecessors;
/* depth of stack upon entry of block, computed by stackdepth() */
int b_startdepth;
/* instruction offset for block, computed by assemble_jump_offsets() */
int b_offset;
/* Basic block has no fall through (it ends with a return, raise or jump) */
unsigned b_nofallthrough : 1;
/* Basic block is an exception handler that preserves lasti */
unsigned b_preserve_lasti : 1;
/* Used by compiler passes to mark whether they have visited a basic block. */
unsigned b_visited : 1;
/* Basic block exits scope (it ends with a return or raise) */
unsigned b_exit : 1;
/* b_return is true if a RETURN_VALUE opcode is inserted. */
unsigned b_return : 1;
} basicblock;
/* fblockinfo tracks the current frame block.
A frame block is used to handle loops, try/except, and try/finally.
It's called a frame block to distinguish it from a basic block in the
compiler IR.
*/
enum fblocktype { WHILE_LOOP, FOR_LOOP, TRY_EXCEPT, FINALLY_TRY, FINALLY_END,
WITH, ASYNC_WITH, HANDLER_CLEANUP, POP_VALUE, EXCEPTION_HANDLER,
EXCEPTION_GROUP_HANDLER, ASYNC_COMPREHENSION_GENERATOR };
struct fblockinfo {
enum fblocktype fb_type;
basicblock *fb_block;
/* (optional) type-specific exit or cleanup block */
basicblock *fb_exit;
/* (optional) additional information required for unwinding */
void *fb_datum;
};
enum {
COMPILER_SCOPE_MODULE,
COMPILER_SCOPE_CLASS,
COMPILER_SCOPE_FUNCTION,
COMPILER_SCOPE_ASYNC_FUNCTION,
COMPILER_SCOPE_LAMBDA,
COMPILER_SCOPE_COMPREHENSION,
};
/* The following items change on entry and exit of code blocks.
They must be saved and restored when returning to a block.
*/
struct compiler_unit {
PySTEntryObject *u_ste;
PyObject *u_name;
PyObject *u_qualname; /* dot-separated qualified name (lazy) */
int u_scope_type;
/* The following fields are dicts that map objects to
the index of them in co_XXX. The index is used as
the argument for opcodes that refer to those collections.
*/
PyObject *u_consts; /* all constants */
PyObject *u_names; /* all names */
PyObject *u_varnames; /* local variables */
PyObject *u_cellvars; /* cell variables */
PyObject *u_freevars; /* free variables */
PyObject *u_private; /* for private name mangling */
Py_ssize_t u_argcount; /* number of arguments for block */
Py_ssize_t u_posonlyargcount; /* number of positional only arguments for block */
Py_ssize_t u_kwonlyargcount; /* number of keyword only arguments for block */
/* Pointer to the most recently allocated block. By following b_list
members, you can reach all early allocated blocks. */
basicblock *u_blocks;
basicblock *u_curblock; /* pointer to current block */
int u_nfblocks;
struct fblockinfo u_fblock[CO_MAXBLOCKS];
int u_firstlineno; /* the first lineno of the block */
int u_lineno; /* the lineno for the current stmt */
int u_col_offset; /* the offset of the current stmt */
int u_end_lineno; /* the end line of the current stmt */
int u_end_col_offset; /* the end offset of the current stmt */
/* true if we need to create an implicit basicblock before the next instr */
int u_need_new_implicit_block;
};
/* This struct captures the global state of a compilation.
The u pointer points to the current compilation unit, while units
for enclosing blocks are stored in c_stack. The u and c_stack are
managed by compiler_enter_scope() and compiler_exit_scope().
Note that we don't track recursion levels during compilation - the
task of detecting and rejecting excessive levels of nesting is
handled by the symbol analysis pass.
*/
struct compiler {
PyObject *c_filename;
struct symtable *c_st;
PyFutureFeatures *c_future; /* pointer to module's __future__ */
PyCompilerFlags *c_flags;
int c_optimize; /* optimization level */
int c_interactive; /* true if in interactive mode */
int c_nestlevel;
PyObject *c_const_cache; /* Python dict holding all constants,
including names tuple */
struct compiler_unit *u; /* compiler state for current block */
PyObject *c_stack; /* Python list holding compiler_unit ptrs */
PyArena *c_arena; /* pointer to memory allocation arena */
};
typedef struct {
// A list of strings corresponding to name captures. It is used to track:
// - Repeated name assignments in the same pattern.
// - Different name assignments in alternatives.
// - The order of name assignments in alternatives.
PyObject *stores;
// If 0, any name captures against our subject will raise.
int allow_irrefutable;
// An array of blocks to jump to on failure. Jumping to fail_pop[i] will pop
// i items off of the stack. The end result looks like this (with each block
// falling through to the next):
// fail_pop[4]: POP_TOP
// fail_pop[3]: POP_TOP
// fail_pop[2]: POP_TOP
// fail_pop[1]: POP_TOP
// fail_pop[0]: NOP
basicblock **fail_pop;
// The current length of fail_pop.
Py_ssize_t fail_pop_size;
// The number of items on top of the stack that need to *stay* on top of the
// stack. Variable captures go beneath these. All of them will be popped on
// failure.
Py_ssize_t on_top;
} pattern_context;
static int compiler_enter_scope(struct compiler *, identifier, int, void *, int);
static void compiler_free(struct compiler *);
static basicblock *compiler_new_block(struct compiler *);
static int compiler_next_instr(basicblock *);
static int compiler_addop(struct compiler *, int);
static int compiler_addop_i(struct compiler *, int, Py_ssize_t);
static int compiler_addop_j(struct compiler *, int, basicblock *);
static int compiler_addop_j_noline(struct compiler *, int, basicblock *);
static int compiler_error(struct compiler *, const char *, ...);
static int compiler_warn(struct compiler *, const char *, ...);
static int compiler_nameop(struct compiler *, identifier, expr_context_ty);
static PyCodeObject *compiler_mod(struct compiler *, mod_ty);
static int compiler_visit_stmt(struct compiler *, stmt_ty);
static int compiler_visit_keyword(struct compiler *, keyword_ty);
static int compiler_visit_expr(struct compiler *, expr_ty);
static int compiler_augassign(struct compiler *, stmt_ty);
static int compiler_annassign(struct compiler *, stmt_ty);
static int compiler_subscript(struct compiler *, expr_ty);
static int compiler_slice(struct compiler *, expr_ty);
static int are_all_items_const(asdl_expr_seq *, Py_ssize_t, Py_ssize_t);
static int compiler_with(struct compiler *, stmt_ty, int);
static int compiler_async_with(struct compiler *, stmt_ty, int);
static int compiler_async_for(struct compiler *, stmt_ty);
static int validate_keywords(struct compiler *c, asdl_keyword_seq *keywords);
static int compiler_call_simple_kw_helper(struct compiler *c,
asdl_keyword_seq *keywords,
Py_ssize_t nkwelts);
static int compiler_call_helper(struct compiler *c, int n,
asdl_expr_seq *args,
asdl_keyword_seq *keywords);
static int compiler_try_except(struct compiler *, stmt_ty);
static int compiler_try_star_except(struct compiler *, stmt_ty);
static int compiler_set_qualname(struct compiler *);
static int compiler_sync_comprehension_generator(
struct compiler *c,
asdl_comprehension_seq *generators, int gen_index,
int depth,
expr_ty elt, expr_ty val, int type);
static int compiler_async_comprehension_generator(
struct compiler *c,
asdl_comprehension_seq *generators, int gen_index,
int depth,
expr_ty elt, expr_ty val, int type);
static int compiler_pattern(struct compiler *, pattern_ty, pattern_context *);
static int compiler_match(struct compiler *, stmt_ty);
static int compiler_pattern_subpattern(struct compiler *, pattern_ty,
pattern_context *);
static void clean_basic_block(basicblock *bb);
static PyCodeObject *assemble(struct compiler *, int addNone);
#define CAPSULE_NAME "compile.c compiler unit"
PyObject *
_Py_Mangle(PyObject *privateobj, PyObject *ident)
{
/* Name mangling: __private becomes _classname__private.
This is independent from how the name is used. */
PyObject *result;
size_t nlen, plen, ipriv;
Py_UCS4 maxchar;
if (privateobj == NULL || !PyUnicode_Check(privateobj) ||
PyUnicode_READ_CHAR(ident, 0) != '_' ||
PyUnicode_READ_CHAR(ident, 1) != '_') {
Py_INCREF(ident);
return ident;
}
nlen = PyUnicode_GET_LENGTH(ident);
plen = PyUnicode_GET_LENGTH(privateobj);
/* Don't mangle __id__ or names with dots.
The only time a name with a dot can occur is when
we are compiling an import statement that has a
package name.
TODO(jhylton): Decide whether we want to support
mangling of the module name, e.g. __M.X.
*/
if ((PyUnicode_READ_CHAR(ident, nlen-1) == '_' &&
PyUnicode_READ_CHAR(ident, nlen-2) == '_') ||
PyUnicode_FindChar(ident, '.', 0, nlen, 1) != -1) {
Py_INCREF(ident);
return ident; /* Don't mangle __whatever__ */
}
/* Strip leading underscores from class name */
ipriv = 0;
while (PyUnicode_READ_CHAR(privateobj, ipriv) == '_')
ipriv++;
if (ipriv == plen) {
Py_INCREF(ident);
return ident; /* Don't mangle if class is just underscores */
}
plen -= ipriv;
if (plen + nlen >= PY_SSIZE_T_MAX - 1) {
PyErr_SetString(PyExc_OverflowError,
"private identifier too large to be mangled");
return NULL;
}
maxchar = PyUnicode_MAX_CHAR_VALUE(ident);
if (PyUnicode_MAX_CHAR_VALUE(privateobj) > maxchar)
maxchar = PyUnicode_MAX_CHAR_VALUE(privateobj);
result = PyUnicode_New(1 + nlen + plen, maxchar);
if (!result)
return 0;
/* ident = "_" + priv[ipriv:] + ident # i.e. 1+plen+nlen bytes */
PyUnicode_WRITE(PyUnicode_KIND(result), PyUnicode_DATA(result), 0, '_');
if (PyUnicode_CopyCharacters(result, 1, privateobj, ipriv, plen) < 0) {
Py_DECREF(result);
return NULL;
}
if (PyUnicode_CopyCharacters(result, plen+1, ident, 0, nlen) < 0) {
Py_DECREF(result);
return NULL;
}
assert(_PyUnicode_CheckConsistency(result, 1));
return result;
}
static int
compiler_init(struct compiler *c)
{
memset(c, 0, sizeof(struct compiler));
c->c_const_cache = PyDict_New();
if (!c->c_const_cache) {
return 0;
}
c->c_stack = PyList_New(0);
if (!c->c_stack) {
Py_CLEAR(c->c_const_cache);
return 0;
}
return 1;
}
PyCodeObject *
_PyAST_Compile(mod_ty mod, PyObject *filename, PyCompilerFlags *flags,
int optimize, PyArena *arena)
{
struct compiler c;
PyCodeObject *co = NULL;
PyCompilerFlags local_flags = _PyCompilerFlags_INIT;
int merged;
if (!compiler_init(&c))
return NULL;
Py_INCREF(filename);
c.c_filename = filename;
c.c_arena = arena;
c.c_future = _PyFuture_FromAST(mod, filename);
if (c.c_future == NULL)
goto finally;
if (!flags) {
flags = &local_flags;
}
merged = c.c_future->ff_features | flags->cf_flags;
c.c_future->ff_features = merged;
flags->cf_flags = merged;
c.c_flags = flags;
c.c_optimize = (optimize == -1) ? _Py_GetConfig()->optimization_level : optimize;
c.c_nestlevel = 0;
_PyASTOptimizeState state;
state.optimize = c.c_optimize;
state.ff_features = merged;
if (!_PyAST_Optimize(mod, arena, &state)) {
goto finally;
}
c.c_st = _PySymtable_Build(mod, filename, c.c_future);
if (c.c_st == NULL) {
if (!PyErr_Occurred())
PyErr_SetString(PyExc_SystemError, "no symtable");
goto finally;
}
co = compiler_mod(&c, mod);
finally:
compiler_free(&c);
assert(co || PyErr_Occurred());
return co;
}
static void
compiler_free(struct compiler *c)
{
if (c->c_st)
_PySymtable_Free(c->c_st);
if (c->c_future)
PyObject_Free(c->c_future);
Py_XDECREF(c->c_filename);
Py_DECREF(c->c_const_cache);
Py_DECREF(c->c_stack);
}
static PyObject *
list2dict(PyObject *list)
{
Py_ssize_t i, n;
PyObject *v, *k;
PyObject *dict = PyDict_New();
if (!dict) return NULL;
n = PyList_Size(list);
for (i = 0; i < n; i++) {
v = PyLong_FromSsize_t(i);
if (!v) {
Py_DECREF(dict);
return NULL;
}
k = PyList_GET_ITEM(list, i);
if (PyDict_SetItem(dict, k, v) < 0) {
Py_DECREF(v);
Py_DECREF(dict);
return NULL;
}
Py_DECREF(v);
}
return dict;
}
/* Return new dict containing names from src that match scope(s).
src is a symbol table dictionary. If the scope of a name matches
either scope_type or flag is set, insert it into the new dict. The
values are integers, starting at offset and increasing by one for
each key.
*/
static PyObject *
dictbytype(PyObject *src, int scope_type, int flag, Py_ssize_t offset)
{
Py_ssize_t i = offset, scope, num_keys, key_i;
PyObject *k, *v, *dest = PyDict_New();
PyObject *sorted_keys;
assert(offset >= 0);
if (dest == NULL)
return NULL;
/* Sort the keys so that we have a deterministic order on the indexes
saved in the returned dictionary. These indexes are used as indexes
into the free and cell var storage. Therefore if they aren't
deterministic, then the generated bytecode is not deterministic.
*/
sorted_keys = PyDict_Keys(src);
if (sorted_keys == NULL)
return NULL;
if (PyList_Sort(sorted_keys) != 0) {
Py_DECREF(sorted_keys);
return NULL;
}
num_keys = PyList_GET_SIZE(sorted_keys);
for (key_i = 0; key_i < num_keys; key_i++) {
/* XXX this should probably be a macro in symtable.h */
long vi;
k = PyList_GET_ITEM(sorted_keys, key_i);
v = PyDict_GetItemWithError(src, k);
assert(v && PyLong_Check(v));
vi = PyLong_AS_LONG(v);
scope = (vi >> SCOPE_OFFSET) & SCOPE_MASK;
if (scope == scope_type || vi & flag) {
PyObject *item = PyLong_FromSsize_t(i);
if (item == NULL) {
Py_DECREF(sorted_keys);
Py_DECREF(dest);
return NULL;
}
i++;
if (PyDict_SetItem(dest, k, item) < 0) {
Py_DECREF(sorted_keys);
Py_DECREF(item);
Py_DECREF(dest);
return NULL;
}
Py_DECREF(item);
}
}
Py_DECREF(sorted_keys);
return dest;
}
static void
compiler_unit_check(struct compiler_unit *u)
{
basicblock *block;
for (block = u->u_blocks; block != NULL; block = block->b_list) {
assert(!_PyMem_IsPtrFreed(block));
if (block->b_instr != NULL) {
assert(block->b_ialloc > 0);
assert(block->b_iused >= 0);
assert(block->b_ialloc >= block->b_iused);
}
else {
assert (block->b_iused == 0);
assert (block->b_ialloc == 0);
}
}
}
static void
compiler_unit_free(struct compiler_unit *u)
{
basicblock *b, *next;
compiler_unit_check(u);
b = u->u_blocks;
while (b != NULL) {
if (b->b_instr)
PyObject_Free((void *)b->b_instr);
next = b->b_list;
PyObject_Free((void *)b);
b = next;
}
Py_CLEAR(u->u_ste);
Py_CLEAR(u->u_name);
Py_CLEAR(u->u_qualname);
Py_CLEAR(u->u_consts);
Py_CLEAR(u->u_names);
Py_CLEAR(u->u_varnames);
Py_CLEAR(u->u_freevars);
Py_CLEAR(u->u_cellvars);
Py_CLEAR(u->u_private);
PyObject_Free(u);
}
static int
compiler_set_qualname(struct compiler *c)
{
Py_ssize_t stack_size;
struct compiler_unit *u = c->u;
PyObject *name, *base;
base = NULL;
stack_size = PyList_GET_SIZE(c->c_stack);
assert(stack_size >= 1);
if (stack_size > 1) {
int scope, force_global = 0;
struct compiler_unit *parent;
PyObject *mangled, *capsule;
capsule = PyList_GET_ITEM(c->c_stack, stack_size - 1);
parent = (struct compiler_unit *)PyCapsule_GetPointer(capsule, CAPSULE_NAME);
assert(parent);
if (u->u_scope_type == COMPILER_SCOPE_FUNCTION
|| u->u_scope_type == COMPILER_SCOPE_ASYNC_FUNCTION
|| u->u_scope_type == COMPILER_SCOPE_CLASS) {
assert(u->u_name);
mangled = _Py_Mangle(parent->u_private, u->u_name);
if (!mangled)
return 0;
scope = _PyST_GetScope(parent->u_ste, mangled);
Py_DECREF(mangled);
assert(scope != GLOBAL_IMPLICIT);
if (scope == GLOBAL_EXPLICIT)
force_global = 1;
}
if (!force_global) {
if (parent->u_scope_type == COMPILER_SCOPE_FUNCTION
|| parent->u_scope_type == COMPILER_SCOPE_ASYNC_FUNCTION
|| parent->u_scope_type == COMPILER_SCOPE_LAMBDA)
{
_Py_DECLARE_STR(dot_locals, ".<locals>");
base = PyUnicode_Concat(parent->u_qualname,
&_Py_STR(dot_locals));
if (base == NULL)
return 0;
}
else {
Py_INCREF(parent->u_qualname);
base = parent->u_qualname;
}
}
}
if (base != NULL) {
_Py_DECLARE_STR(dot, ".");
name = PyUnicode_Concat(base, &_Py_STR(dot));
Py_DECREF(base);
if (name == NULL)
return 0;
PyUnicode_Append(&name, u->u_name);
if (name == NULL)
return 0;
}
else {
Py_INCREF(u->u_name);
name = u->u_name;
}
u->u_qualname = name;
return 1;
}
/* Allocate a new block and return a pointer to it.
Returns NULL on error.
*/
static basicblock *
compiler_new_block(struct compiler *c)
{
basicblock *b;
struct compiler_unit *u;
u = c->u;
b = (basicblock *)PyObject_Calloc(1, sizeof(basicblock));
if (b == NULL) {
PyErr_NoMemory();
return NULL;
}
/* Extend the singly linked list of blocks with new block. */
b->b_list = u->u_blocks;
u->u_blocks = b;
return b;
}
static basicblock *
compiler_use_next_block(struct compiler *c, basicblock *block)
{
assert(block != NULL);
c->u->u_curblock->b_next = block;
c->u->u_curblock = block;
c->u->u_need_new_implicit_block = 0;
return block;
}
static basicblock *
compiler_copy_block(struct compiler *c, basicblock *block)
{
/* Cannot copy a block if it has a fallthrough, since
* a block can only have one fallthrough predecessor.
*/
assert(block->b_nofallthrough);
basicblock *result = compiler_new_block(c);
if (result == NULL) {
return NULL;
}
for (int i = 0; i < block->b_iused; i++) {
int n = compiler_next_instr(result);
if (n < 0) {
return NULL;
}
result->b_instr[n] = block->b_instr[i];
}
result->b_exit = block->b_exit;
result->b_nofallthrough = 1;
return result;
}
/* Returns the offset of the next instruction in the current block's
b_instr array. Resizes the b_instr as necessary.
Returns -1 on failure.
*/
static int
compiler_next_instr(basicblock *b)
{
assert(b != NULL);
if (b->b_instr == NULL) {
b->b_instr = (struct instr *)PyObject_Calloc(
DEFAULT_BLOCK_SIZE, sizeof(struct instr));
if (b->b_instr == NULL) {
PyErr_NoMemory();
return -1;
}
b->b_ialloc = DEFAULT_BLOCK_SIZE;
}
else if (b->b_iused == b->b_ialloc) {
struct instr *tmp;
size_t oldsize, newsize;
oldsize = b->b_ialloc * sizeof(struct instr);
newsize = oldsize << 1;
if (oldsize > (SIZE_MAX >> 1)) {
PyErr_NoMemory();
return -1;
}
if (newsize == 0) {
PyErr_NoMemory();
return -1;
}
b->b_ialloc <<= 1;
tmp = (struct instr *)PyObject_Realloc(
(void *)b->b_instr, newsize);
if (tmp == NULL) {
PyErr_NoMemory();
return -1;
}
b->b_instr = tmp;
memset((char *)b->b_instr + oldsize, 0, newsize - oldsize);
}
return b->b_iused++;
}
/* Set the line number and column offset for the following instructions.
The line number is reset in the following cases:
- when entering a new scope
- on each statement
- on each expression and sub-expression
- before the "except" and "finally" clauses
*/
#define SET_LOC(c, x) \
(c)->u->u_lineno = (x)->lineno; \
(c)->u->u_col_offset = (x)->col_offset; \
(c)->u->u_end_lineno = (x)->end_lineno; \
(c)->u->u_end_col_offset = (x)->end_col_offset;
// Artificial instructions
#define UNSET_LOC(c) \
(c)->u->u_lineno = -1; \
(c)->u->u_col_offset = -1; \
(c)->u->u_end_lineno = -1; \
(c)->u->u_end_col_offset = -1;
#define COPY_INSTR_LOC(old, new) \
(new).i_lineno = (old).i_lineno; \
(new).i_col_offset = (old).i_col_offset; \
(new).i_end_lineno = (old).i_end_lineno; \
(new).i_end_col_offset = (old).i_end_col_offset;
/* Return the stack effect of opcode with argument oparg.
Some opcodes have different stack effect when jump to the target and
when not jump. The 'jump' parameter specifies the case:
* 0 -- when not jump
* 1 -- when jump
* -1 -- maximal
*/
static int
stack_effect(int opcode, int oparg, int jump)
{
switch (opcode) {
case NOP:
case EXTENDED_ARG:
case RESUME:
case CACHE:
return 0;
/* Stack manipulation */
case POP_TOP:
return -1;
case SWAP:
return 0;
/* Unary operators */
case UNARY_POSITIVE:
case UNARY_NEGATIVE:
case UNARY_NOT:
case UNARY_INVERT:
return 0;
case SET_ADD:
case LIST_APPEND:
return -1;
case MAP_ADD:
return -2;
case BINARY_SUBSCR:
return -1;
case STORE_SUBSCR:
return -3;
case DELETE_SUBSCR:
return -2;
case GET_ITER:
return 0;
case PRINT_EXPR:
return -1;
case LOAD_BUILD_CLASS:
return 1;
case RETURN_VALUE:
return -1;
case IMPORT_STAR:
return -1;
case SETUP_ANNOTATIONS:
return 0;
case ASYNC_GEN_WRAP:
case YIELD_VALUE:
return 0;
case POP_BLOCK:
return 0;
case POP_EXCEPT:
return -1;