forked from emscripten-core/emscripten
-
Notifications
You must be signed in to change notification settings - Fork 0
/
emscripten.py
2584 lines (2122 loc) · 101 KB
/
emscripten.py
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
# Copyright 2010 The Emscripten Authors. All rights reserved.
# Emscripten is available under two separate licenses, the MIT license and the
# University of Illinois/NCSA Open Source License. Both these licenses can be
# found in the LICENSE file.
"""A small wrapper script around the core JS compiler. This calls that
compiler with the settings given to it. It can also read data from C/C++
header files (so that the JS compiler can see the constants in those
headers, for the libc implementation in JS).
"""
from __future__ import print_function
import difflib
import os
import json
import subprocess
import re
import time
import logging
import pprint
from collections import OrderedDict
from tools import building
from tools import diagnostics
from tools import shared
from tools import gen_struct_info
from tools import jsrun
from tools.response_file import substitute_response_files
from tools.shared import WINDOWS, asstr, path_from_root, exit_with_error, asmjs_mangle, treat_as_user_function
from tools.toolchain_profiler import ToolchainProfiler
from tools.minified_js_name_generator import MinifiedJsNameGenerator
logger = logging.getLogger('emscripten')
STDERR_FILE = os.environ.get('EMCC_STDERR_FILE')
if STDERR_FILE:
STDERR_FILE = os.path.abspath(STDERR_FILE)
logger.info('logging stderr in js compiler phase into %s' % STDERR_FILE)
STDERR_FILE = open(STDERR_FILE, 'w')
def quote(prop):
if shared.Settings.USE_CLOSURE_COMPILER == 2:
return ''.join(["'" + p + "'" for p in prop.split('.')])
else:
return prop
def access_quote(prop):
if shared.Settings.USE_CLOSURE_COMPILER == 2:
return ''.join(["['" + p + "']" for p in prop.split('.')])
else:
return '.' + prop
def emscript_fastcomp(infile, outfile, memfile, temp_files, DEBUG):
"""Runs the emscripten LLVM-to-JS compiler.
Args:
infile: The path to the input LLVM assembly file.
outfile: An open file object where the output is written.
"""
assert shared.Settings.ASM_JS, 'fastcomp is asm.js-only (mode 1 or 2)'
success = False
try:
# Overview:
# * Run LLVM backend to emit JS. JS includes function bodies, memory initializer,
# and various metadata
# * Run compiler.js on the metadata to emit the shell js code, pre/post-ambles,
# JS library dependencies, etc.
# metadata is modified by reference in some of the below
# these functions are split up to force variables to go out of scope and allow
# memory to be reclaimed
with ToolchainProfiler.profile_block('get_and_parse_backend'):
backend_output = compile_js(infile, temp_files, DEBUG)
funcs, metadata, mem_init = parse_fastcomp_output(backend_output, DEBUG)
fixup_metadata_tables(metadata)
funcs = fixup_functions(funcs, metadata)
with ToolchainProfiler.profile_block('compiler_glue'):
glue, forwarded_data = compiler_glue(metadata, temp_files, DEBUG)
with ToolchainProfiler.profile_block('function_tables_and_exports'):
(post, function_table_data, bundled_args) = (
function_tables_and_exports(funcs, metadata, mem_init, glue, forwarded_data, outfile, DEBUG))
with ToolchainProfiler.profile_block('write_output_file'):
finalize_output(outfile, post, function_table_data, bundled_args, metadata, DEBUG)
success = True
finally:
outfile.close()
if not success:
shared.try_delete(outfile.name) # remove partial output
def compile_js(infile, temp_files, DEBUG):
"""Compile infile with asm.js backend, return the contents of the compiled js"""
with temp_files.get_file('.4.js') as temp_js:
backend_cmd = create_backend_cmd(infile, temp_js)
if DEBUG:
logger.debug('emscript: llvm backend: ' + ' '.join(backend_cmd))
t = time.time()
shared.print_compiler_stage(backend_cmd)
with ToolchainProfiler.profile_block('emscript_llvm_backend'):
shared.check_call(backend_cmd)
if DEBUG:
logger.debug(' emscript: llvm backend took %s seconds' % (time.time() - t))
# Split up output
backend_output = open(temp_js).read()
return backend_output
def parse_fastcomp_output(backend_output, DEBUG):
start_funcs_marker = '// EMSCRIPTEN_START_FUNCTIONS'
end_funcs_marker = '// EMSCRIPTEN_END_FUNCTIONS'
metadata_split_marker = '// EMSCRIPTEN_METADATA'
start_funcs = backend_output.index(start_funcs_marker)
end_funcs = backend_output.rindex(end_funcs_marker)
metadata_split = backend_output.rindex(metadata_split_marker)
funcs = backend_output[start_funcs + len(start_funcs_marker):end_funcs]
metadata_raw = backend_output[metadata_split + len(metadata_split_marker):]
mem_init = backend_output[end_funcs + len(end_funcs_marker):metadata_split]
# we no longer use the "Runtime" object. TODO: stop emitting it in the backend
mem_init = mem_init.replace('Runtime.', '')
try:
metadata = json.loads(metadata_raw, object_pairs_hook=OrderedDict)
except ValueError:
logger.error('emscript: failure to parse metadata output from compiler backend. raw output is: \n' + metadata_raw)
raise
# This key is being added to fastcomp but doesn't exist in the current
# version.
metadata.setdefault('externFunctions', [])
if 'externUses' not in metadata:
exit_with_error('Your fastcomp compiler is out of date, please update! (need >= 1.38.26)')
# JS optimizer turns some heap accesses to others as an optimization, so make HEAP8 imply HEAPU8, HEAP16->HEAPU16, and HEAPF64->HEAPF32.
if 'Int8Array' in metadata['externUses']:
metadata['externUses'] += ['Uint8Array']
if 'Int16Array' in metadata['externUses']:
metadata['externUses'] += ['Uint16Array']
if 'Float64Array' in metadata['externUses']:
metadata['externUses'] += ['Float32Array']
# If we are generating references to Math.fround() from here in emscripten.py, declare it used as well.
if provide_fround():
metadata['externUses'] += ['Math.fround']
# functions marked llvm.used in the code are exports requested by the user
building.user_requested_exports += metadata['exports']
# stackSave() and stackRestore() are JS library functions. If fastcomp generated
# calls to invoke_*() functions that save and restore the stack, we must include the stack functions
# explicitly into the build.
# In traditional runtime we always require these functions. For example stackAlloc is used
# allocate argv on the stack before calling main.
if shared.Settings.MINIMAL_RUNTIME:
if len(metadata['invokeFuncs']) > 0 or shared.Settings.LINKABLE:
shared.Settings.EXPORTED_FUNCTIONS += ['stackSave', 'stackRestore']
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += ['$stackSave', '$stackRestore']
else:
shared.Settings.EXPORTED_FUNCTIONS += ['stackSave', 'stackRestore', 'stackAlloc']
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += ['$stackSave', '$stackRestore', '$stackAlloc']
return funcs, metadata, mem_init
def fixup_metadata_tables(metadata):
# if emulating pointer casts, force all tables to the size of the largest
# (for wasm, we use binaryen's fpcast-emu pass, we don't need to do anything
# here)
if shared.Settings.EMULATE_FUNCTION_POINTER_CASTS and not shared.Settings.WASM:
max_size = 0
for k, v in metadata['tables'].items():
max_size = max(max_size, v.count(',') + 1)
for k, v in metadata['tables'].items():
curr = v.count(',') + 1
if curr < max_size:
if v.count('[]') == 1:
metadata['tables'][k] = v.replace(']', (','.join(['0'] * (max_size - curr)) + ']'))
else:
metadata['tables'][k] = v.replace(']', (',0' * (max_size - curr)) + ']')
if shared.Settings.SIDE_MODULE:
for k in metadata['tables'].keys():
metadata['tables'][k] = metadata['tables'][k].replace('var FUNCTION_TABLE_', 'var SIDE_FUNCTION_TABLE_')
def fixup_functions(funcs, metadata):
# function table masks
table_sizes = {}
for k, v in metadata['tables'].items():
# undercounts by one, but that is what we want
table_sizes[k] = str(v.count(','))
# if shared.Settings.ASSERTIONS >= 2 and table_sizes[k] == 0:
# diagnostics.warning('emcc', 'no function pointers with signature ' + k + ', but there is a call, which will abort if it occurs (this can result from undefined behavior, check for compiler warnings on your source files and consider -Werror)'
funcs = re.sub(r"#FM_(\w+)#", lambda m: table_sizes[m.groups(0)[0]], funcs)
# fix +float into float.0, if not running js opts
if not shared.Settings.RUNNING_JS_OPTS:
def fix_dot_zero(m):
num = m.group(3)
# TODO: handle 0x floats?
if num.find('.') < 0:
e = num.find('e')
if e < 0:
num += '.0'
else:
num = num[:e] + '.0' + num[e:]
return m.group(1) + m.group(2) + num
funcs = re.sub(r'([(=,+\-*/%<>:?] *)\+(-?)((0x)?[0-9a-f]*\.?[0-9]+([eE][-+]?[0-9]+)?)', fix_dot_zero, funcs)
return funcs
def compiler_glue(metadata, temp_files, DEBUG):
if DEBUG:
logger.debug('emscript: js compiler glue')
t = time.time()
# FIXME: do these one by one as normal js lib funcs
metadata['declares'] = [i64_func for i64_func in metadata['declares'] if i64_func not in ['getHigh32', 'setHigh32']]
update_settings_glue(metadata, DEBUG)
assert not metadata['simd'], 'Obsolete SIMD.js was used'
glue, forwarded_data = compile_settings(temp_files)
if DEBUG:
logger.debug(' emscript: glue took %s seconds' % (time.time() - t))
return glue, forwarded_data
def analyze_table(function_table_data):
def table_size(table):
table_contents = table[table.index('[') + 1: table.index(']')]
if len(table_contents) == 0: # empty table
return 0
return table_contents.count(',') + 1
# note that this is a minimal estimate, as when asm2wasm lays out tables it adds padding
table_total_size = sum(table_size(s) for s in function_table_data.values())
shared.Settings.WASM_TABLE_SIZE = table_total_size
# Extracts from JS library code dependencies to runtime primitives.
def get_asm_extern_primitives(pre):
primitives = re.search(r'\/\/ ASM_LIBRARY EXTERN PRIMITIVES: ([^\n]*)', pre)
if primitives:
return [x.strip().replace('Math_', 'Math.') for x in primitives.group(1).split(',')]
else:
return []
def compute_minimal_runtime_initializer_and_exports(post, initializers, exports, receiving):
# Generate invocations for all global initializers directly off the asm export object, e.g. asm['__GLOBAL__INIT']();
post = post.replace('/*** RUN_GLOBAL_INITIALIZERS(); ***/', '\n'.join(["asm['" + x + "']();" for x in global_initializer_funcs(initializers)]))
if shared.Settings.WASM:
# Declare all exports out to global JS scope so that JS library functions can access them in a
# way that minifies well with Closure
# e.g. var a,b,c,d,e,f;
exports_that_are_not_initializers = [x for x in exports if x not in initializers]
if shared.Settings.WASM_BACKEND:
# In Wasm backend the exports are still unmangled at this point, so mangle the names here
exports_that_are_not_initializers = [asmjs_mangle(x) for x in exports_that_are_not_initializers]
post = post.replace('/*** ASM_MODULE_EXPORTS_DECLARES ***/', 'var ' + ','.join(exports_that_are_not_initializers) + ';')
# Generate assignments from all asm.js/wasm exports out to the JS variables above: e.g. a = asm['a']; b = asm['b'];
post = post.replace('/*** ASM_MODULE_EXPORTS ***/', receiving)
receiving = ''
return post, receiving
def function_tables_and_exports(funcs, metadata, mem_init, glue, forwarded_data, outfile, DEBUG):
if DEBUG:
logger.debug('emscript: python processing: function tables and exports')
t = time.time()
forwarded_json = json.loads(forwarded_data)
# merge in information from llvm backend
function_table_data = metadata['tables']
if shared.Settings.WASM:
analyze_table(function_table_data)
# merge forwarded data
shared.Settings.EXPORTED_FUNCTIONS = forwarded_json['EXPORTED_FUNCTIONS']
pre, post = glue.split('// EMSCRIPTEN_END_FUNCS')
pre = apply_script_source(pre)
asm_extern_primitives = get_asm_extern_primitives(pre)
metadata['externUses'] += asm_extern_primitives
pre = memory_and_global_initializers(pre, metadata, mem_init)
pre, funcs_js = get_js_funcs(pre, funcs)
all_exported_functions = get_all_exported_functions(function_table_data)
all_implemented = get_all_implemented(forwarded_json, metadata)
report_missing_symbols(all_implemented, pre)
implemented_functions = get_implemented_functions(metadata)
pre = include_asm_consts(pre, forwarded_json, metadata)
pre = apply_table(pre)
outfile.write(pre)
pre = None
# Move preAsms to their right place
def move_preasm(m):
contents = m.groups(0)[0]
outfile.write(contents + '\n')
return ''
if not shared.Settings.BOOTSTRAPPING_STRUCT_INFO and len(funcs_js) > 1:
funcs_js[1] = re.sub(r'/\* PRE_ASM \*/(.*)\n', move_preasm, funcs_js[1])
if 'pre' in function_table_data:
pre_tables = function_table_data['pre']
del function_table_data['pre']
else:
pre_tables = ''
function_table_sigs = list(function_table_data.keys())
in_table, debug_tables, function_tables_defs = make_function_tables_defs(
implemented_functions, all_implemented, function_table_data, metadata)
exported_implemented_functions = get_exported_implemented_functions(
all_exported_functions, all_implemented, metadata)
# List of function signatures of used 'invoke_xxx()' functions in the application
# For backwards compatibility if one might be using a mismatching Emscripten compiler version, if 'invokeFuncs' is not present in metadata,
# use the full list of signatures in function table and generate invoke_() functions for all signatures in the program (producing excessive code size)
# we must also emit the full list if we are emitting code that can be linked later
if 'invokeFuncs' in metadata and not shared.Settings.LINKABLE:
invoke_function_names = metadata['invokeFuncs']
else:
invoke_function_names = ['invoke_' + x for x in function_table_sigs]
asm_setup = create_asm_setup(debug_tables, function_table_data, invoke_function_names, metadata)
basic_funcs = create_basic_funcs(function_table_sigs, invoke_function_names)
basic_vars = create_basic_vars(exported_implemented_functions, forwarded_json, metadata)
funcs_js += create_mftCall_funcs(function_table_data)
exports = create_exports(exported_implemented_functions, in_table, function_table_data, metadata)
# calculate globals
try:
del forwarded_json['Variables']['globals']['_llvm_global_ctors'] # not a true variable
except KeyError:
pass
if not shared.Settings.RELOCATABLE:
global_vars = metadata['externs']
else:
global_vars = [] # linkable code accesses globals through function calls
global_funcs = set(key for key, value in forwarded_json['Functions']['libraryFunctions'].items() if value != 2)
global_funcs = sorted(global_funcs.difference(set(global_vars)).difference(implemented_functions))
if shared.Settings.RELOCATABLE:
global_funcs += ['g$' + extern for extern in metadata['externs']]
global_funcs += ['fp$' + extern for extern in metadata['externFunctions']]
# Tracks the set of used (minified) function names in
# JS symbols imported to asm.js module.
minified_js_names = MinifiedJsNameGenerator()
# Converts list of imports ['foo', 'bar', ...] to a dictionary of
# name mappings in form { 'minified': 'unminified', ... }
def define_asmjs_import_names(imports):
if shared.Settings.MINIFY_ASMJS_IMPORT_NAMES:
return [(minified_js_names.generate(), i) for i in imports]
else:
return [(i, i) for i in imports]
basic_funcs = define_asmjs_import_names(basic_funcs)
global_funcs = define_asmjs_import_names(global_funcs)
basic_vars = define_asmjs_import_names(basic_vars)
global_vars = define_asmjs_import_names(global_vars)
bg_funcs = basic_funcs + global_funcs
bg_vars = basic_vars + global_vars
asm_global_funcs = create_asm_global_funcs(bg_funcs, metadata)
asm_global_vars = create_asm_global_vars(bg_vars)
the_global = create_the_global(metadata)
sending_vars = bg_funcs + bg_vars
sending = OrderedDict([(math_fix(minified), unminified) for (minified, unminified) in sending_vars])
if shared.Settings.WASM:
add_standard_wasm_imports(sending)
sorted_sending_keys = sorted(sending.keys())
sending = '{ ' + ', '.join('"' + k + '": ' + sending[k] for k in sorted_sending_keys) + ' }'
receiving = create_receiving(function_table_data, function_tables_defs,
exported_implemented_functions, metadata['initializers'])
post = apply_table(post)
post = apply_static_code_hooks(post)
if shared.Settings.MINIMAL_RUNTIME:
post, receiving = compute_minimal_runtime_initializer_and_exports(post, metadata['initializers'], [mangled for mangled, unmangled in shared.Settings.MODULE_EXPORTS], receiving)
function_tables_impls = make_function_tables_impls(function_table_data)
final_function_tables = '\n'.join(function_tables_impls) + '\n' + function_tables_defs
if shared.Settings.EMULATED_FUNCTION_POINTERS:
final_function_tables = (
final_function_tables
.replace("asm['", '')
.replace("']", '')
.replace('var SIDE_FUNCTION_TABLE_', 'var FUNCTION_TABLE_')
.replace('var dynCall_', '//')
)
if DEBUG:
logger.debug('asm text sizes' + str([
[len(s) for s in funcs_js], len(asm_setup), len(asm_global_vars), len(asm_global_funcs), len(pre_tables),
len('\n'.join(function_tables_impls)), len(function_tables_defs) + (function_tables_defs.count('\n') * len(' ')),
len(exports), len(the_global), len(sending), len(receiving)]))
logger.debug(' emscript: python processing: function tables and exports took %s seconds' % (time.time() - t))
bundled_args = (funcs_js, asm_setup, the_global, sending, receiving, asm_global_vars,
asm_global_funcs, pre_tables, final_function_tables, exports)
return (post, function_table_data, bundled_args)
def finalize_output(outfile, post, function_table_data, bundled_args, metadata, DEBUG):
function_table_sigs = function_table_data.keys()
module = create_module_asmjs(function_table_sigs, metadata, *bundled_args)
if DEBUG:
logger.debug('emscript: python processing: finalize')
t = time.time()
write_output_file(outfile, post, module)
module = None
if DEBUG:
logger.debug(' emscript: python processing: finalize took %s seconds' % (time.time() - t))
write_cyberdwarf_data(outfile, metadata)
# Given JS code that consists only exactly of a series of "var a = ...;\n var b = ...;" statements,
# this function collapses the redundant 'var ' statements at the beginning of each line to a
# single var a =..., b=..., c=...; statement.
def collapse_redundant_vars(code):
if shared.Settings.WASM:
return code # Skip if targeting Wasm, this does not matter there
old_code = ''
while code != old_code: # Repeated vars overlap, so can't run in one regex pass. Runs in O(log(N)) time
old_code = code
code = re.sub(r'(var [^;]*);\s*var ', r'\1,\n ', code)
return code
def global_initializer_funcs(initializers):
# If we have at most one global ctor, no need to group global initializers.
# Also in EVAL_CTORS mode, we want to try to evaluate the individual ctor functions, so in that mode,
# do not group ctors into one.
return ['globalCtors'] if (len(initializers) > 1 and not shared.Settings.EVAL_CTORS) else initializers
# Each .cpp file with global constructors generates a __GLOBAL__init() function that needs to be
# called to construct the global objects in that compilation unit. This function groups all these
# global initializer functions together into a single globalCtors() function that lives inside the
# asm.js/wasm module, and gets exported out to JS scope to be called at the startup of the application.
def create_global_initializer(initializers):
# If we have no global ctors, don't even generate a dummy empty function to save code space
# Also in EVAL_CTORS mode, we want to try to evaluate the individual ctor functions, so in that mode,
# we do not group ctors into one.
if 'globalCtors' not in global_initializer_funcs(initializers):
return ''
global_initializer = '''function globalCtors() {
%s
}''' % '\n '.join(i + '();' for i in initializers)
return global_initializer
def create_module_asmjs(function_table_sigs, metadata,
funcs_js, asm_setup, the_global, sending, receiving, asm_global_vars,
asm_global_funcs, pre_tables, final_function_tables, exports):
receiving += create_named_globals(metadata)
runtime_funcs = create_runtime_funcs_asmjs(exports, metadata)
asm_start_pre = create_asm_start_pre(asm_setup, the_global, sending, metadata)
memory_views = create_memory_views(metadata)
asm_temp_vars = create_asm_temp_vars(metadata)
asm_runtime_thread_local_vars = create_asm_runtime_thread_local_vars()
stack = ''
if not shared.Settings.RELOCATABLE and not (shared.Settings.WASM and shared.Settings.SIDE_MODULE):
if 'STACKTOP' in shared.Settings.ASM_PRIMITIVE_VARS:
stack += apply_memory(' var STACKTOP = {{{ STACK_BASE }}};\n')
if 'STACK_MAX' in shared.Settings.ASM_PRIMITIVE_VARS:
stack += apply_memory(' var STACK_MAX = {{{ STACK_MAX }}};\n')
if 'tempFloat' in shared.Settings.ASM_PRIMITIVE_VARS:
temp_float = ' var tempFloat = %s;\n' % ('Math_fround(0)' if provide_fround() else '0.0')
else:
temp_float = ''
f0_fround = ' const f0 = Math_fround(0);\n' if provide_fround() else ''
replace_memory = create_replace_memory(metadata)
start_funcs_marker = '\n// EMSCRIPTEN_START_FUNCS\n'
asm_end = create_asm_end(exports)
asm_variables = collapse_redundant_vars(memory_views + asm_global_vars + asm_temp_vars + asm_runtime_thread_local_vars + '\n' + asm_global_funcs + stack + temp_float + f0_fround)
asm_global_initializer = create_global_initializer(metadata['initializers'])
module = [
asm_start_pre,
asm_variables,
replace_memory,
start_funcs_marker,
asm_global_initializer
] + runtime_funcs + funcs_js + [
'\n ',
pre_tables, final_function_tables, asm_end,
'\n', receiving, ';\n'
]
if shared.Settings.SIDE_MODULE:
module.append('''
parentModule['registerFunctions'](%s, Module);
''' % str([str(f) for f in function_table_sigs]))
return module
def write_output_file(outfile, post, module):
for i in range(len(module)): # do this loop carefully to save memory
module[i] = normalize_line_endings(module[i])
outfile.write(module[i])
post = normalize_line_endings(post)
outfile.write(post)
def write_cyberdwarf_data(outfile, metadata):
if not shared.Settings.CYBERDWARF:
return
assert('cyberdwarf_data' in metadata)
cd_file_name = outfile.name + ".cd"
with open(cd_file_name, 'w') as f:
json.dump({'cyberdwarf': metadata['cyberdwarf_data']}, f)
def create_backend_cmd(infile, temp_js):
"""Create asm.js backend command from settings dict"""
args = [
shared.LLVM_COMPILER, infile, '-march=js', '-filetype=asm', '-o', temp_js,
'-emscripten-stack-size=%d' % shared.Settings.TOTAL_STACK,
'-O%s' % shared.Settings.OPT_LEVEL,
]
if shared.Settings.PRECISE_F32:
args += ['-emscripten-precise-f32']
if shared.Settings.USE_PTHREADS:
args += ['-emscripten-enable-pthreads']
if shared.Settings.WARN_UNALIGNED:
args += ['-emscripten-warn-unaligned']
if shared.Settings.RESERVED_FUNCTION_POINTERS > 0:
args += ['-emscripten-reserved-function-pointers=%d' % shared.Settings.RESERVED_FUNCTION_POINTERS]
if shared.Settings.ASSERTIONS > 0:
args += ['-emscripten-assertions=%d' % shared.Settings.ASSERTIONS]
if shared.Settings.ALIASING_FUNCTION_POINTERS == 0:
args += ['-emscripten-no-aliasing-function-pointers']
if shared.Settings.EMULATED_FUNCTION_POINTERS:
args += ['-emscripten-emulated-function-pointers']
if shared.Settings.EMULATE_FUNCTION_POINTER_CASTS:
args += ['-emscripten-emulate-function-pointer-casts']
if shared.Settings.RELOCATABLE:
args += ['-emscripten-relocatable']
args += ['-emscripten-global-base=0']
elif shared.Settings.GLOBAL_BASE >= 0:
args += ['-emscripten-global-base=%d' % shared.Settings.GLOBAL_BASE]
if shared.Settings.SIDE_MODULE:
args += ['-emscripten-side-module']
if shared.Settings.LEGALIZE_JS_FFI != 1:
args += ['-emscripten-legalize-javascript-ffi=0']
if shared.Settings.DISABLE_EXCEPTION_CATCHING != 1:
args += ['-enable-emscripten-cpp-exceptions']
if shared.Settings.DISABLE_EXCEPTION_CATCHING == 2:
args += ['-emscripten-cpp-exceptions-whitelist=' + ','.join(shared.Settings.EXCEPTION_CATCHING_WHITELIST or ['fake'])]
if not shared.Settings.EXIT_RUNTIME:
args += ['-emscripten-no-exit-runtime']
if shared.Settings.WORKAROUND_IOS_9_RIGHT_SHIFT_BUG:
args += ['-emscripten-asmjs-work-around-ios-9-right-shift-bug']
if shared.Settings.WASM:
args += ['-emscripten-wasm']
if building.is_wasm_only():
args += ['-emscripten-only-wasm']
if shared.Settings.CYBERDWARF:
args += ['-enable-cyberdwarf']
return args
def optimize_syscalls(declares, DEBUG):
"""Disables filesystem if only a limited subset of syscalls is used.
Our syscalls are static, and so if we see a very limited set of them - in particular,
no open() syscall and just simple writing - then we don't need full filesystem support.
If FORCE_FILESYSTEM is set, we can't do this. We also don't do it if INCLUDE_FULL_LIBRARY, since
not including the filesystem would mean not including the full JS libraries, and the same for
MAIN_MODULE since a side module might need the filesystem.
"""
relevant_settings = ['FORCE_FILESYSTEM', 'INCLUDE_FULL_LIBRARY', 'MAIN_MODULE']
if any(shared.Settings[s] for s in relevant_settings):
return
if shared.Settings.FILESYSTEM == 0:
# without filesystem support, it doesn't matter what syscalls need
shared.Settings.SYSCALLS_REQUIRE_FILESYSTEM = 0
else:
syscall_prefixes = ('__sys', 'fd_', '__wasi_fd_')
syscalls = [d for d in declares if d.startswith(syscall_prefixes)]
# check if the only filesystem syscalls are in: close, ioctl, llseek, write
# (without open, etc.. nothing substantial can be done, so we can disable
# extra filesystem support in that case)
if set(syscalls).issubset(set([
'__sys_ioctl',
# legacy/fastcomp name for __sys_ioctl
'__syscall6',
'fd_seek', '__wasi_fd_seek',
'fd_write', '__wasi_fd_write',
'fd_close', '__wasi_fd_close',
])):
if DEBUG:
logger.debug('very limited syscalls (%s) so disabling full filesystem support', ', '.join(str(s) for s in syscalls))
shared.Settings.SYSCALLS_REQUIRE_FILESYSTEM = 0
def is_int(x):
try:
int(x)
return True
except ValueError:
return False
def align_memory(addr):
return (addr + 15) & -16
def align_static_bump(metadata):
metadata['staticBump'] = align_memory(metadata['staticBump'])
return metadata['staticBump']
def update_settings_glue(metadata, DEBUG):
optimize_syscalls(metadata['declares'], DEBUG)
if shared.Settings.CYBERDWARF:
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE.append("cyberdwarf_Debugger")
shared.Settings.EXPORTED_FUNCTIONS.append("cyberdwarf_Debugger")
# Integrate info from backend
if shared.Settings.SIDE_MODULE:
# we don't need any JS library contents in side modules
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE = []
if metadata.get('cantValidate') and shared.Settings.ASM_JS != 2:
diagnostics.warning('almost-asm', 'disabling asm.js validation due to use of non-supported features: ' + metadata['cantValidate'])
shared.Settings.ASM_JS = 2
all_funcs = shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE + [shared.JS.to_nice_ident(d) for d in metadata['declares']]
implemented_funcs = [x[1:] for x in metadata['implementedFunctions']]
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE = sorted(set(all_funcs).difference(implemented_funcs))
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += [x[1:] for x in metadata['externs']]
shared.Settings.MAX_GLOBAL_ALIGN = metadata['maxGlobalAlign']
shared.Settings.IMPLEMENTED_FUNCTIONS = metadata['implementedFunctions']
shared.Settings.WEAK_DECLARES = metadata.get('weakDeclares', [])
if metadata['asmConsts']:
# emit the EM_ASM signature-reading helper function only if we have any EM_ASM
# functions in the module.
shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE += ['$readAsmConstArgs']
# Extract the list of function signatures that MAIN_THREAD_EM_ASM blocks in
# the compiled code have, each signature will need a proxy function invoker
# generated for it.
def read_proxied_function_signatures(asmConsts):
proxied_function_signatures = set()
for _, sigs, proxying_types in asmConsts.values():
for sig, proxying_type in zip(sigs, proxying_types):
if proxying_type == 'sync_on_main_thread_':
proxied_function_signatures.add(sig + '_sync')
elif proxying_type == 'async_on_main_thread_':
proxied_function_signatures.add(sig + '_async')
return list(proxied_function_signatures)
shared.Settings.PROXIED_FUNCTION_SIGNATURES = read_proxied_function_signatures(metadata['asmConsts'])
shared.Settings.STATIC_BUMP = align_static_bump(metadata)
if shared.Settings.WASM_BACKEND:
shared.Settings.BINARYEN_FEATURES = metadata['features']
shared.Settings.WASM_TABLE_SIZE = metadata['tableSize']
if shared.Settings.RELOCATABLE:
# When building relocatable output (e.g. MAIN_MODULE) the reported table
# size does not include the reserved slot at zero for the null pointer.
# Instead we use __table_base to offset the elements by 1.
shared.Settings.WASM_TABLE_SIZE += 1
shared.Settings.MAIN_READS_PARAMS = metadata['mainReadsParams']
# static code hooks
class StaticCodeHooks:
atinits = []
atmains = []
atexits = []
def apply_static_code_hooks(code):
code = code.replace('{{{ ATINITS }}}', StaticCodeHooks.atinits)
code = code.replace('{{{ ATMAINS }}}', StaticCodeHooks.atmains)
code = code.replace('{{{ ATEXITS }}}', StaticCodeHooks.atexits)
return code
def apply_forwarded_data(forwarded_data):
forwarded_json = json.loads(forwarded_data)
# Be aware of JS static allocations
shared.Settings.STATIC_BUMP = forwarded_json['STATIC_BUMP']
shared.Settings.DYNAMICTOP_PTR = forwarded_json['DYNAMICTOP_PTR']
# Be aware of JS static code hooks
StaticCodeHooks.atinits = str(forwarded_json['ATINITS'])
StaticCodeHooks.atmains = str(forwarded_json['ATMAINS'])
StaticCodeHooks.atexits = str(forwarded_json['ATEXITS'])
def compile_settings(temp_files):
# Save settings to a file to work around v8 issue 1579
with temp_files.get_file('.txt') as settings_file:
with open(settings_file, 'w') as s:
json.dump(shared.Settings.to_dict(), s, sort_keys=True)
# Call js compiler
env = os.environ.copy()
env['EMCC_BUILD_DIR'] = os.getcwd()
out = jsrun.run_js_tool(path_from_root('src', 'compiler.js'), shared.NODE_JS,
[settings_file], stdout=subprocess.PIPE, stderr=STDERR_FILE,
cwd=path_from_root('src'), env=env)
assert '//FORWARDED_DATA:' in out, 'Did not receive forwarded data in pre output - process failed?'
glue, forwarded_data = out.split('//FORWARDED_DATA:')
apply_forwarded_data(forwarded_data)
return glue, forwarded_data
class Memory():
def __init__(self):
# Note: if RELOCATABLE, then only relative sizes can be computed, and we don't
# actually write out any absolute memory locations ({{{ STACK_BASE }}}
# does not exist, etc.)
# Memory layout:
# * first the static globals
self.global_base = shared.Settings.GLOBAL_BASE
self.static_bump = shared.Settings.STATIC_BUMP
# * then the stack (up on fastcomp, down on upstream)
self.stack_low = align_memory(self.global_base + self.static_bump)
self.stack_high = align_memory(self.stack_low + shared.Settings.TOTAL_STACK)
if shared.Settings.WASM_BACKEND:
self.stack_base = self.stack_high
self.stack_max = self.stack_low
else:
self.stack_base = self.stack_low
self.stack_max = self.stack_high
# * then dynamic memory begins
self.dynamic_base = align_memory(self.stack_high)
if self.dynamic_base >= shared.Settings.INITIAL_MEMORY:
exit_with_error('Memory is not large enough for static data (%d) plus the stack (%d), please increase INITIAL_MEMORY (%d) to at least %d' % (self.static_bump, shared.Settings.TOTAL_STACK, shared.Settings.INITIAL_MEMORY, self.dynamic_base))
def apply_memory(js):
# Apply the statically-at-compile-time computed memory locations.
memory = Memory()
# Write it all out
js = js.replace('{{{ STATIC_BUMP }}}', str(memory.static_bump))
js = js.replace('{{{ STACK_BASE }}}', str(memory.stack_base))
js = js.replace('{{{ STACK_MAX }}}', str(memory.stack_max))
js = js.replace('{{{ DYNAMIC_BASE }}}', str(memory.dynamic_base))
logger.debug('global_base: %d stack_base: %d, stack_max: %d, dynamic_base: %d, static bump: %d', memory.global_base, memory.stack_base, memory.stack_max, memory.dynamic_base, memory.static_bump)
shared.Settings.DYNAMIC_BASE = memory.dynamic_base
shared.Settings.STACK_BASE = memory.stack_base
return js
def apply_table(js):
js = js.replace('{{{ WASM_TABLE_SIZE }}}', str(shared.Settings.WASM_TABLE_SIZE))
return js
def apply_script_source(js):
js = js.replace('{{{ TARGET_BASENAME }}}', shared.Settings.TARGET_BASENAME)
return js
def memory_and_global_initializers(pre, metadata, mem_init):
staticbump = shared.Settings.STATIC_BUMP
pthread = ''
if shared.Settings.USE_PTHREADS:
pthread = 'if (!ENVIRONMENT_IS_PTHREAD)'
global_initializers = ''
if not shared.Settings.MINIMAL_RUNTIME:
# In traditional runtime, global initializers are pushed to the __ATINIT__ array to be processed when runtime is loaded
# In MINIMAL_RUNTIME global initializers are invoked directly off of the asm[''] export object, so this does not apply.
global_initializers = global_initializer_funcs(metadata['initializers'])
if len(global_initializers) > 0:
global_initializers = ', '.join('{ func: function() { %s() } }' % i for i in global_initializers)
global_initializers = '/* global initializers */ {pthread} __ATINIT__.push({global_initializers});'.format(pthread=pthread, global_initializers=global_initializers)
else:
global_initializers = '/* global initializers */ /*__ATINIT__.push();*/'
pre = pre.replace('STATICTOP = STATIC_BASE + 0;', '''\
STATICTOP = STATIC_BASE + {staticbump};
{global_initializers}
{mem_init}'''.format(staticbump=staticbump,
global_initializers=global_initializers,
mem_init=mem_init))
if shared.Settings.SIDE_MODULE:
pre = pre.replace('GLOBAL_BASE', 'gb')
pre = apply_memory(pre)
pre = apply_static_code_hooks(pre)
return pre
def get_js_funcs(pre, funcs):
funcs_js = [funcs]
parts = pre.split('// ASM_LIBRARY FUNCTIONS\n')
if len(parts) > 1:
pre = parts[0]
funcs_js.append(parts[1])
return pre, funcs_js
def get_all_exported_functions(function_table_data):
# both asm.js and otherwise
all_exported_functions = set(shared.Settings.EXPORTED_FUNCTIONS)
# additional functions to export from asm, if they are implemented
for additional_export in shared.Settings.DEFAULT_LIBRARY_FUNCS_TO_INCLUDE:
all_exported_functions.add('_' + additional_export)
if shared.Settings.EXPORT_FUNCTION_TABLES:
for table in function_table_data.values():
for func in table.split('[')[1].split(']')[0].split(','):
if func[0] == '_':
all_exported_functions.add(func)
return all_exported_functions
def get_all_implemented(forwarded_json, metadata):
return set(metadata['implementedFunctions']).union(forwarded_json['Functions']['implementedFunctions'])
def report_missing_symbols(all_implemented, pre):
# we are not checking anyway, so just skip this
if not shared.Settings.ERROR_ON_UNDEFINED_SYMBOLS and not shared.Settings.WARN_ON_UNDEFINED_SYMBOLS:
return
# the initial list of missing functions are that the user explicitly exported
# but were not implemented in compiled code
missing = list(set(shared.Settings.USER_EXPORTED_FUNCTIONS) - all_implemented)
for requested in missing:
if ('function ' + asstr(requested)) in pre:
continue
# special-case malloc, EXPORTED by default for internal use, but we bake in a
# trivial allocator and warn at runtime if used in ASSERTIONS
if missing == '_malloc':
continue
diagnostics.warning('undefined', 'undefined exported function: "%s"', requested)
# Handle main specially, unless IGNORE_MISSING_MAIN is set
if shared.Settings.EXPECT_MAIN and '_main' not in all_implemented and not shared.Settings.IGNORE_MISSING_MAIN:
# For compatibility with the output of wasm-ld we use the same wording here in our
# error message as if wasm-ld had failed (i.e. in LLD_REPORT_UNDEFINED mode).
exit_with_error('entry symbol not defined (pass --no-entry to suppress): main')
def get_exported_implemented_functions(all_exported_functions, all_implemented, metadata):
funcs = set(metadata['exports'])
export_bindings = shared.Settings.EXPORT_BINDINGS
export_all = shared.Settings.EXPORT_ALL
for key in all_implemented:
if key in all_exported_functions or export_all or (export_bindings and key.startswith('_emscripten_bind')):
funcs.add(key)
if not export_all:
for name, alias in metadata['aliases'].items():
# here we export the aliases,
# if not the side module (which imports the alias)
# will not be able to get to the actual implementation
if alias in all_implemented and name in all_exported_functions:
funcs.add(alias)
funcs = list(funcs) + global_initializer_funcs(metadata['initializers'])
if shared.Settings.ALLOW_MEMORY_GROWTH:
funcs.append('_emscripten_replace_memory')
if shared.Settings.USE_PTHREADS:
funcs += ['asmJsEstablishStackFrame']
return sorted(set(funcs))
def get_implemented_functions(metadata):
return set(metadata['implementedFunctions'])
def proxy_debug_print(sync):
if shared.Settings.PTHREADS_DEBUG:
if sync:
return 'warnOnce("sync proxying function " + code);'
else:
return 'warnOnce("async proxying function " + code);'
return ''
def include_asm_consts(pre, forwarded_json, metadata):
if shared.Settings.WASM and shared.Settings.SIDE_MODULE:
if metadata['asmConsts']:
exit_with_error('EM_ASM is not yet supported in shared wasm module (it cannot be stored in the wasm itself, need some solution)')
asm_consts, all_sigs = all_asm_consts(metadata)
asm_const_funcs = []
for sig, call_type in all_sigs:
if 'j' in sig:
exit_with_error('emscript: EM_ASM should not receive i64s as inputs, they are not valid in JS')
if '_emscripten_asm_const_' + call_type + sig in forwarded_json['Functions']['libraryFunctions']:
continue # Only one invoker needs to be emitted for each ASM_CONST (signature x call_type) item
forwarded_json['Functions']['libraryFunctions']['_emscripten_asm_const_' + call_type + sig] = 1
args = ['a%d' % i for i in range(len(sig) - 1)]
all_args = ['code'] + args
pre_asm_const = ''
if shared.Settings.USE_PTHREADS:
sync_proxy = call_type == 'sync_on_main_thread_'
async_proxy = call_type == 'async_on_main_thread_'
proxied = sync_proxy or async_proxy
if proxied:
# In proxied function calls, positive integers 1, 2, 3, ... denote pointers
# to regular C compiled functions. Negative integers -1, -2, -3, ... denote
# indices to EM_ASM() blocks, so remap the EM_ASM() indices from 0, 1, 2,
# ... over to the negative integers starting at -1.
proxy_args = ['-1 - code', str(int(sync_proxy))] + args
pre_asm_const += ' if (ENVIRONMENT_IS_PTHREAD) { ' + proxy_debug_print(sync_proxy) + 'return _emscripten_proxy_to_main_thread_js(' + ', '.join(proxy_args) + '); }\n'
asm_const_funcs.append(r'''
function _emscripten_asm_const_%s(%s) {
%s return ASM_CONSTS[code](%s);
}''' % (call_type + asstr(sig), ', '.join(all_args), pre_asm_const, ', '.join(args)))
asm_consts_text = '\nvar ASM_CONSTS = [' + ',\n '.join(asm_consts) + '];\n'
asm_funcs_text = '\n'.join(asm_const_funcs) + '\n'
em_js_funcs = create_em_js(forwarded_json, metadata)
em_js_text = '\n'.join(em_js_funcs) + '\n'
body_marker = '// === Body ==='
return pre.replace(body_marker, body_marker + '\n' + asm_consts_text + asstr(asm_funcs_text) + em_js_text)