forked from ethereum/solidity
-
Notifications
You must be signed in to change notification settings - Fork 0
/
Copy pathCompilerUtils.cpp
1513 lines (1414 loc) · 52.6 KB
/
CompilerUtils.cpp
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 is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @author Christian <[email protected]>
* @date 2014
* Routines used by both the compiler and the expression compiler.
*/
#include <libsolidity/codegen/CompilerUtils.h>
#include <libsolidity/ast/AST.h>
#include <libsolidity/ast/TypeProvider.h>
#include <libsolidity/codegen/ABIFunctions.h>
#include <libsolidity/codegen/ArrayUtils.h>
#include <libsolidity/codegen/LValue.h>
#include <libevmasm/Instruction.h>
#include <libsolutil/Whiskers.h>
using namespace std;
using namespace solidity;
using namespace solidity::evmasm;
using namespace solidity::frontend;
using namespace solidity::langutil;
using solidity::util::Whiskers;
using solidity::util::h256;
using solidity::util::toCompactHexWithPrefix;
unsigned const CompilerUtils::dataStartOffset = 4;
size_t const CompilerUtils::freeMemoryPointer = 64;
size_t const CompilerUtils::zeroPointer = CompilerUtils::freeMemoryPointer + 32;
size_t const CompilerUtils::generalPurposeMemoryStart = CompilerUtils::zeroPointer + 32;
static_assert(CompilerUtils::freeMemoryPointer >= 64, "Free memory pointer must not overlap with scratch area.");
static_assert(CompilerUtils::zeroPointer >= CompilerUtils::freeMemoryPointer + 32, "Zero pointer must not overlap with free memory pointer.");
static_assert(CompilerUtils::generalPurposeMemoryStart >= CompilerUtils::zeroPointer + 32, "General purpose memory must not overlap with zero area.");
void CompilerUtils::initialiseFreeMemoryPointer()
{
m_context << u256(generalPurposeMemoryStart);
storeFreeMemoryPointer();
}
void CompilerUtils::fetchFreeMemoryPointer()
{
m_context << u256(freeMemoryPointer) << Instruction::MLOAD;
}
void CompilerUtils::storeFreeMemoryPointer()
{
m_context << u256(freeMemoryPointer) << Instruction::MSTORE;
}
void CompilerUtils::allocateMemory()
{
fetchFreeMemoryPointer();
m_context << Instruction::SWAP1 << Instruction::DUP2 << Instruction::ADD;
storeFreeMemoryPointer();
}
void CompilerUtils::allocateMemory(u256 const& size)
{
fetchFreeMemoryPointer();
m_context << Instruction::DUP1 << size << Instruction::ADD;
storeFreeMemoryPointer();
}
void CompilerUtils::toSizeAfterFreeMemoryPointer()
{
fetchFreeMemoryPointer();
m_context << Instruction::DUP1 << Instruction::SWAP2 << Instruction::SUB;
m_context << Instruction::SWAP1;
}
void CompilerUtils::revertWithStringData(Type const& _argumentType)
{
solAssert(_argumentType.isImplicitlyConvertibleTo(*TypeProvider::fromElementaryTypeName("string memory")), "");
fetchFreeMemoryPointer();
m_context << (u256(util::FixedHash<4>::Arith(util::FixedHash<4>(util::keccak256("Error(string)")))) << (256 - 32));
m_context << Instruction::DUP2 << Instruction::MSTORE;
m_context << u256(4) << Instruction::ADD;
// Stack: <string data> <mem pos of encoding start>
abiEncode({&_argumentType}, {TypeProvider::array(DataLocation::Memory, true)});
toSizeAfterFreeMemoryPointer();
m_context << Instruction::REVERT;
}
void CompilerUtils::returnDataToArray()
{
if (m_context.evmVersion().supportsReturndata())
{
m_context << Instruction::RETURNDATASIZE;
m_context.appendInlineAssembly(R"({
switch v case 0 {
v := 0x60
} default {
v := mload(0x40)
mstore(0x40, add(v, and(add(returndatasize(), 0x3f), not(0x1f))))
mstore(v, returndatasize())
returndatacopy(add(v, 0x20), 0, returndatasize())
}
})", {"v"});
}
else
pushZeroPointer();
}
void CompilerUtils::accessCalldataTail(Type const& _type)
{
solAssert(_type.dataStoredIn(DataLocation::CallData), "");
solAssert(_type.isDynamicallyEncoded(), "");
unsigned int tailSize = _type.calldataEncodedTailSize();
solAssert(tailSize > 1, "");
// returns the absolute offset of the tail in "base_ref"
m_context.appendInlineAssembly(Whiskers(R"({
let rel_offset_of_tail := calldataload(ptr_to_tail)
if iszero(slt(rel_offset_of_tail, sub(sub(calldatasize(), base_ref), sub(<neededLength>, 1)))) { <revertString> }
base_ref := add(base_ref, rel_offset_of_tail)
})")
("neededLength", toCompactHexWithPrefix(tailSize))
("revertString", m_context.revertReasonIfDebug("Invalid calldata tail offset"))
.render(), {"base_ref", "ptr_to_tail"});
// stack layout: <absolute_offset_of_tail> <garbage>
if (!_type.isDynamicallySized())
{
m_context << Instruction::POP;
// stack layout: <absolute_offset_of_tail>
solAssert(
_type.category() == Type::Category::Struct ||
_type.category() == Type::Category::Array,
"Invalid dynamically encoded base type on tail access."
);
}
else
{
auto const* arrayType = dynamic_cast<ArrayType const*>(&_type);
solAssert(!!arrayType, "Invalid dynamically sized type.");
unsigned int calldataStride = arrayType->calldataStride();
solAssert(calldataStride > 0, "");
// returns the absolute offset of the tail in "base_ref"
// and the length of the tail in "length"
m_context.appendInlineAssembly(
Whiskers(R"({
length := calldataload(base_ref)
base_ref := add(base_ref, 0x20)
if gt(length, 0xffffffffffffffff) { <revertString> }
if sgt(base_ref, sub(calldatasize(), mul(length, <calldataStride>))) { revert(0, 0) }
})")
("calldataStride", toCompactHexWithPrefix(calldataStride))
("revertString", m_context.revertReasonIfDebug("Invalid calldata tail length"))
.render(),
{"base_ref", "length"}
);
// stack layout: <absolute_offset_of_tail> <length>
}
}
unsigned CompilerUtils::loadFromMemory(
unsigned _offset,
Type const& _type,
bool _fromCalldata,
bool _padToWordBoundaries
)
{
solAssert(_type.category() != Type::Category::Array, "Unable to statically load dynamic type.");
m_context << u256(_offset);
return loadFromMemoryHelper(_type, _fromCalldata, _padToWordBoundaries);
}
void CompilerUtils::loadFromMemoryDynamic(
Type const& _type,
bool _fromCalldata,
bool _padToWordBoundaries,
bool _keepUpdatedMemoryOffset
)
{
if (_keepUpdatedMemoryOffset)
m_context << Instruction::DUP1;
if (auto arrayType = dynamic_cast<ArrayType const*>(&_type))
{
solAssert(!arrayType->isDynamicallySized(), "");
solAssert(!_fromCalldata, "");
solAssert(_padToWordBoundaries, "");
if (_keepUpdatedMemoryOffset)
m_context << arrayType->memoryDataSize() << Instruction::ADD;
}
else
{
unsigned numBytes = loadFromMemoryHelper(_type, _fromCalldata, _padToWordBoundaries);
if (_keepUpdatedMemoryOffset)
{
// update memory counter
moveToStackTop(_type.sizeOnStack());
m_context << u256(numBytes) << Instruction::ADD;
}
}
}
void CompilerUtils::storeInMemory(unsigned _offset)
{
unsigned numBytes = prepareMemoryStore(*TypeProvider::uint256(), true);
if (numBytes > 0)
m_context << u256(_offset) << Instruction::MSTORE;
}
void CompilerUtils::storeInMemoryDynamic(Type const& _type, bool _padToWordBoundaries)
{
// process special types (Reference, StringLiteral, Function)
if (auto ref = dynamic_cast<ReferenceType const*>(&_type))
{
solUnimplementedAssert(
ref->location() == DataLocation::Memory,
"Only in-memory reference type can be stored."
);
storeInMemoryDynamic(*TypeProvider::uint256(), _padToWordBoundaries);
}
else if (auto str = dynamic_cast<StringLiteralType const*>(&_type))
{
m_context << Instruction::DUP1;
storeStringData(bytesConstRef(str->value()));
if (_padToWordBoundaries)
m_context << u256(max<size_t>(32, ((str->value().size() + 31) / 32) * 32));
else
m_context << u256(str->value().size());
m_context << Instruction::ADD;
}
else if (
_type.category() == Type::Category::Function &&
dynamic_cast<FunctionType const&>(_type).kind() == FunctionType::Kind::External
)
{
combineExternalFunctionType(true);
m_context << Instruction::DUP2 << Instruction::MSTORE;
m_context << u256(_padToWordBoundaries ? 32 : 24) << Instruction::ADD;
}
else if (_type.isValueType())
{
unsigned numBytes = prepareMemoryStore(_type, _padToWordBoundaries);
m_context << Instruction::DUP2 << Instruction::MSTORE;
m_context << u256(numBytes) << Instruction::ADD;
}
else // Should never happen
{
solAssert(
false,
"Memory store of type " + _type.toString(true) + " not allowed."
);
}
}
void CompilerUtils::abiDecode(TypePointers const& _typeParameters, bool _fromMemory)
{
/// Stack: <source_offset> <length>
if (m_context.experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2))
{
// Use the new Yul-based decoding function
auto stackHeightBefore = m_context.stackHeight();
abiDecodeV2(_typeParameters, _fromMemory);
solAssert(m_context.stackHeight() - stackHeightBefore == sizeOnStack(_typeParameters) - 2, "");
return;
}
//@todo this does not yet support nested dynamic arrays
size_t encodedSize = 0;
for (auto const& t: _typeParameters)
encodedSize += t->decodingType()->calldataHeadSize();
Whiskers templ(R"({
if lt(len, <encodedSize>) { <revertString> }
})");
templ("encodedSize", to_string(encodedSize));
templ("revertString", m_context.revertReasonIfDebug("Calldata too short"));
m_context.appendInlineAssembly(templ.render(), {"len"});
m_context << Instruction::DUP2 << Instruction::ADD;
m_context << Instruction::SWAP1;
/// Stack: <input_end> <source_offset>
// Retain the offset pointer as base_offset, the point from which the data offsets are computed.
m_context << Instruction::DUP1;
for (TypePointer const& parameterType: _typeParameters)
{
// stack: v1 v2 ... v(k-1) input_end base_offset current_offset
TypePointer type = parameterType->decodingType();
solUnimplementedAssert(type, "No decoding type found.");
if (type->category() == Type::Category::Array)
{
auto const& arrayType = dynamic_cast<ArrayType const&>(*type);
solUnimplementedAssert(!arrayType.baseType()->isDynamicallyEncoded(), "Nested arrays not yet implemented.");
if (_fromMemory)
{
solUnimplementedAssert(
arrayType.baseType()->isValueType(),
"Nested memory arrays not yet implemented here."
);
// @todo If base type is an array or struct, it is still calldata-style encoded, so
// we would have to convert it like below.
solAssert(arrayType.location() == DataLocation::Memory, "");
if (arrayType.isDynamicallySized())
{
// compute data pointer
m_context << Instruction::DUP1 << Instruction::MLOAD;
// stack: v1 v2 ... v(k-1) input_end base_offset current_offset data_offset
fetchFreeMemoryPointer();
// stack: v1 v2 ... v(k-1) input_end base_offset current_offset data_offset dstmem
moveIntoStack(4);
// stack: v1 v2 ... v(k-1) dstmem input_end base_offset current_offset data_offset
m_context << Instruction::DUP5;
// stack: v1 v2 ... v(k-1) dstmem input_end base_offset current_offset data_offset dstmem
// Check that the data pointer is valid and that length times
// item size is still inside the range.
Whiskers templ(R"({
if gt(ptr, 0x100000000) { <revertStringPointer> }
ptr := add(ptr, base_offset)
let array_data_start := add(ptr, 0x20)
if gt(array_data_start, input_end) { <revertStringStart> }
let array_length := mload(ptr)
if or(
gt(array_length, 0x100000000),
gt(add(array_data_start, mul(array_length, <item_size>)), input_end)
) { <revertStringLength> }
mstore(dst, array_length)
dst := add(dst, 0x20)
})");
templ("item_size", to_string(arrayType.calldataStride()));
// TODO add test
templ("revertStringPointer", m_context.revertReasonIfDebug("ABI memory decoding: invalid data pointer"));
templ("revertStringStart", m_context.revertReasonIfDebug("ABI memory decoding: invalid data start"));
templ("revertStringLength", m_context.revertReasonIfDebug("ABI memory decoding: invalid data length"));
m_context.appendInlineAssembly(templ.render(), {"input_end", "base_offset", "offset", "ptr", "dst"});
// stack: v1 v2 ... v(k-1) dstmem input_end base_offset current_offset data_ptr dstdata
m_context << Instruction::SWAP1;
// stack: v1 v2 ... v(k-1) dstmem input_end base_offset current_offset dstdata data_ptr
ArrayUtils(m_context).copyArrayToMemory(arrayType, true);
// stack: v1 v2 ... v(k-1) dstmem input_end base_offset current_offset mem_end
storeFreeMemoryPointer();
m_context << u256(0x20) << Instruction::ADD;
}
else
{
// Size has already been checked for this one.
moveIntoStack(2);
m_context << Instruction::DUP3;
m_context << u256(arrayType.calldataHeadSize()) << Instruction::ADD;
}
}
else
{
// first load from calldata and potentially convert to memory if arrayType is memory
TypePointer calldataType = TypeProvider::withLocation(&arrayType, DataLocation::CallData, false);
if (calldataType->isDynamicallySized())
{
// put on stack: data_pointer length
loadFromMemoryDynamic(*TypeProvider::uint256(), !_fromMemory);
m_context << Instruction::SWAP1;
// stack: input_end base_offset next_pointer data_offset
m_context.appendInlineAssembly(Whiskers(R"({
if gt(data_offset, 0x100000000) { <revertString> }
})")
// TODO add test
("revertString", m_context.revertReasonIfDebug("ABI calldata decoding: invalid data offset"))
.render(), {"data_offset"});
m_context << Instruction::DUP3 << Instruction::ADD;
// stack: input_end base_offset next_pointer array_head_ptr
m_context.appendInlineAssembly(Whiskers(R"({
if gt(add(array_head_ptr, 0x20), input_end) { <revertString> }
})")
("revertString", m_context.revertReasonIfDebug("ABI calldata decoding: invalid head pointer"))
.render(), {"input_end", "base_offset", "next_ptr", "array_head_ptr"});
// retrieve length
loadFromMemoryDynamic(*TypeProvider::uint256(), !_fromMemory, true);
// stack: input_end base_offset next_pointer array_length data_pointer
m_context << Instruction::SWAP2;
// stack: input_end base_offset data_pointer array_length next_pointer
m_context.appendInlineAssembly(Whiskers(R"({
if or(
gt(array_length, 0x100000000),
gt(add(data_ptr, mul(array_length, )" + to_string(arrayType.calldataStride()) + R"()), input_end)
) { <revertString> }
})")
("revertString", m_context.revertReasonIfDebug("ABI calldata decoding: invalid data pointer"))
.render(), {"input_end", "base_offset", "data_ptr", "array_length", "next_ptr"});
}
else
{
// size has already been checked
// stack: input_end base_offset data_offset
m_context << Instruction::DUP1;
m_context << u256(calldataType->calldataHeadSize()) << Instruction::ADD;
}
if (arrayType.location() == DataLocation::Memory)
{
// stack: input_end base_offset calldata_ref [length] next_calldata
// copy to memory
// move calldata type up again
moveIntoStack(calldataType->sizeOnStack());
convertType(*calldataType, arrayType, false, false, true);
// fetch next pointer again
moveToStackTop(arrayType.sizeOnStack());
}
// move input_end up
// stack: input_end base_offset calldata_ref [length] next_calldata
moveToStackTop(2 + arrayType.sizeOnStack());
m_context << Instruction::SWAP1;
// stack: base_offset calldata_ref [length] input_end next_calldata
moveToStackTop(2 + arrayType.sizeOnStack());
m_context << Instruction::SWAP1;
// stack: calldata_ref [length] input_end base_offset next_calldata
}
}
else
{
solAssert(!type->isDynamicallyEncoded(), "Unknown dynamically sized type: " + type->toString());
loadFromMemoryDynamic(*type, !_fromMemory, true);
// stack: v1 v2 ... v(k-1) input_end base_offset v(k) mem_offset
moveToStackTop(1, type->sizeOnStack());
moveIntoStack(3, type->sizeOnStack());
}
// stack: v1 v2 ... v(k-1) v(k) input_end base_offset next_offset
}
popStackSlots(3);
}
void CompilerUtils::encodeToMemory(
TypePointers const& _givenTypes,
TypePointers const& _targetTypes,
bool _padToWordBoundaries,
bool _copyDynamicDataInPlace,
bool _encodeAsLibraryTypes
)
{
// stack: <v1> <v2> ... <vn> <mem>
bool const encoderV2 = m_context.experimentalFeatureActive(ExperimentalFeature::ABIEncoderV2);
TypePointers targetTypes = _targetTypes.empty() ? _givenTypes : _targetTypes;
solAssert(targetTypes.size() == _givenTypes.size(), "");
for (TypePointer& t: targetTypes)
{
TypePointer tEncoding = t->fullEncodingType(_encodeAsLibraryTypes, encoderV2, !_padToWordBoundaries);
solUnimplementedAssert(tEncoding, "Encoding type \"" + t->toString() + "\" not yet implemented.");
t = std::move(tEncoding);
}
if (_givenTypes.empty())
return;
if (encoderV2)
{
// Use the new Yul-based encoding function
solAssert(
_padToWordBoundaries != _copyDynamicDataInPlace,
"Non-padded and in-place encoding can only be combined."
);
auto stackHeightBefore = m_context.stackHeight();
abiEncodeV2(_givenTypes, targetTypes, _encodeAsLibraryTypes, _padToWordBoundaries);
solAssert(stackHeightBefore - m_context.stackHeight() == sizeOnStack(_givenTypes), "");
return;
}
// Stack during operation:
// <v1> <v2> ... <vn> <mem_start> <dyn_head_1> ... <dyn_head_r> <end_of_mem>
// The values dyn_head_n are added during the first loop and they point to the head part
// of the nth dynamic parameter, which is filled once the dynamic parts are processed.
// store memory start pointer
m_context << Instruction::DUP1;
unsigned argSize = CompilerUtils::sizeOnStack(_givenTypes);
unsigned stackPos = 0; // advances through the argument values
unsigned dynPointers = 0; // number of dynamic head pointers on the stack
for (size_t i = 0; i < _givenTypes.size(); ++i)
{
TypePointer targetType = targetTypes[i];
solAssert(!!targetType, "Externalable type expected.");
if (targetType->isDynamicallySized() && !_copyDynamicDataInPlace)
{
// leave end_of_mem as dyn head pointer
m_context << Instruction::DUP1 << u256(32) << Instruction::ADD;
dynPointers++;
solAssert((argSize + dynPointers) < 16, "Stack too deep, try using fewer variables.");
}
else
{
copyToStackTop(argSize - stackPos + dynPointers + 2, _givenTypes[i]->sizeOnStack());
solAssert(!!targetType, "Externalable type expected.");
TypePointer type = targetType;
if (_givenTypes[i]->dataStoredIn(DataLocation::Storage) && targetType->isValueType())
{
// special case: convert storage reference type to value type - this is only
// possible for library calls where we just forward the storage reference
solAssert(_encodeAsLibraryTypes, "");
solAssert(_givenTypes[i]->sizeOnStack() == 1, "");
}
else if (
_givenTypes[i]->dataStoredIn(DataLocation::Storage) ||
_givenTypes[i]->dataStoredIn(DataLocation::CallData) ||
_givenTypes[i]->category() == Type::Category::StringLiteral ||
_givenTypes[i]->category() == Type::Category::Function
)
type = _givenTypes[i]; // delay conversion
else
convertType(*_givenTypes[i], *targetType, true);
if (auto arrayType = dynamic_cast<ArrayType const*>(type))
ArrayUtils(m_context).copyArrayToMemory(*arrayType, _padToWordBoundaries);
else
storeInMemoryDynamic(*type, _padToWordBoundaries);
}
stackPos += _givenTypes[i]->sizeOnStack();
}
// now copy the dynamic part
// Stack: <v1> <v2> ... <vn> <mem_start> <dyn_head_1> ... <dyn_head_r> <end_of_mem>
stackPos = 0;
unsigned thisDynPointer = 0;
for (size_t i = 0; i < _givenTypes.size(); ++i)
{
TypePointer targetType = targetTypes[i];
solAssert(!!targetType, "Externalable type expected.");
if (targetType->isDynamicallySized() && !_copyDynamicDataInPlace)
{
// copy tail pointer (=mem_end - mem_start) to memory
m_context << dupInstruction(2 + dynPointers) << Instruction::DUP2;
m_context << Instruction::SUB;
m_context << dupInstruction(2 + dynPointers - thisDynPointer);
m_context << Instruction::MSTORE;
// stack: ... <end_of_mem>
if (_givenTypes[i]->category() == Type::Category::StringLiteral)
{
auto const& strType = dynamic_cast<StringLiteralType const&>(*_givenTypes[i]);
m_context << u256(strType.value().size());
storeInMemoryDynamic(*TypeProvider::uint256(), true);
// stack: ... <end_of_mem'>
storeInMemoryDynamic(strType, _padToWordBoundaries);
}
else
{
solAssert(_givenTypes[i]->category() == Type::Category::Array, "Unknown dynamic type.");
auto const& arrayType = dynamic_cast<ArrayType const&>(*_givenTypes[i]);
// now copy the array
copyToStackTop(argSize - stackPos + dynPointers + 2, arrayType.sizeOnStack());
// stack: ... <end_of_mem> <value...>
// copy length to memory
m_context << dupInstruction(1 + arrayType.sizeOnStack());
ArrayUtils(m_context).retrieveLength(arrayType, 1);
// stack: ... <end_of_mem> <value...> <end_of_mem'> <length>
storeInMemoryDynamic(*TypeProvider::uint256(), true);
// stack: ... <end_of_mem> <value...> <end_of_mem''>
// copy the new memory pointer
m_context << swapInstruction(arrayType.sizeOnStack() + 1) << Instruction::POP;
// stack: ... <end_of_mem''> <value...>
// copy data part
ArrayUtils(m_context).copyArrayToMemory(arrayType, _padToWordBoundaries);
// stack: ... <end_of_mem'''>
}
thisDynPointer++;
}
stackPos += _givenTypes[i]->sizeOnStack();
}
// remove unneeded stack elements (and retain memory pointer)
m_context << swapInstruction(argSize + dynPointers + 1);
popStackSlots(argSize + dynPointers + 1);
}
void CompilerUtils::abiEncodeV2(
TypePointers const& _givenTypes,
TypePointers const& _targetTypes,
bool _encodeAsLibraryTypes,
bool _padToWordBoundaries
)
{
if (!_padToWordBoundaries)
solAssert(!_encodeAsLibraryTypes, "Library calls cannot be packed.");
// stack: <$value0> <$value1> ... <$value(n-1)> <$headStart>
auto ret = m_context.pushNewTag();
moveIntoStack(sizeOnStack(_givenTypes) + 1);
string encoderName =
_padToWordBoundaries ?
m_context.abiFunctions().tupleEncoder(_givenTypes, _targetTypes, _encodeAsLibraryTypes) :
m_context.abiFunctions().tupleEncoderPacked(_givenTypes, _targetTypes);
m_context.appendJumpTo(m_context.namedTag(encoderName));
m_context.adjustStackOffset(-int(sizeOnStack(_givenTypes)) - 1);
m_context << ret.tag();
}
void CompilerUtils::abiDecodeV2(TypePointers const& _parameterTypes, bool _fromMemory)
{
// stack: <source_offset> <length> [stack top]
auto ret = m_context.pushNewTag();
moveIntoStack(2);
// stack: <return tag> <source_offset> <length> [stack top]
m_context << Instruction::DUP2 << Instruction::ADD;
m_context << Instruction::SWAP1;
// stack: <return tag> <end> <start>
string decoderName = m_context.abiFunctions().tupleDecoder(_parameterTypes, _fromMemory);
m_context.appendJumpTo(m_context.namedTag(decoderName));
m_context.adjustStackOffset(int(sizeOnStack(_parameterTypes)) - 3);
m_context << ret.tag();
}
void CompilerUtils::zeroInitialiseMemoryArray(ArrayType const& _type)
{
if (_type.baseType()->hasSimpleZeroValueInMemory())
{
solAssert(_type.baseType()->isValueType(), "");
Whiskers templ(R"({
let size := mul(length, <element_size>)
// cheap way of zero-initializing a memory range
calldatacopy(memptr, calldatasize(), size)
memptr := add(memptr, size)
})");
templ("element_size", to_string(_type.memoryStride()));
m_context.appendInlineAssembly(templ.render(), {"length", "memptr"});
}
else
{
auto repeat = m_context.newTag();
m_context << repeat;
pushZeroValue(*_type.baseType());
storeInMemoryDynamic(*_type.baseType());
m_context << Instruction::SWAP1 << u256(1) << Instruction::SWAP1;
m_context << Instruction::SUB << Instruction::SWAP1;
m_context << Instruction::DUP2;
m_context.appendConditionalJumpTo(repeat);
}
m_context << Instruction::SWAP1 << Instruction::POP;
}
void CompilerUtils::memoryCopy32()
{
// Stack here: size target source
m_context.appendInlineAssembly(R"(
{
for { let i := 0 } lt(i, len) { i := add(i, 32) } {
mstore(add(dst, i), mload(add(src, i)))
}
}
)",
{ "len", "dst", "src" }
);
m_context << Instruction::POP << Instruction::POP << Instruction::POP;
}
void CompilerUtils::memoryCopy()
{
// Stack here: size target source
m_context.appendInlineAssembly(R"(
{
// copy 32 bytes at once
for
{}
iszero(lt(len, 32))
{
dst := add(dst, 32)
src := add(src, 32)
len := sub(len, 32)
}
{ mstore(dst, mload(src)) }
// copy the remainder (0 < len < 32)
let mask := sub(exp(256, sub(32, len)), 1)
let srcpart := and(mload(src), not(mask))
let dstpart := and(mload(dst), mask)
mstore(dst, or(srcpart, dstpart))
}
)",
{ "len", "dst", "src" }
);
m_context << Instruction::POP << Instruction::POP << Instruction::POP;
}
void CompilerUtils::splitExternalFunctionType(bool _leftAligned)
{
// We have to split the left-aligned <address><function identifier> into two stack slots:
// address (right aligned), function identifier (right aligned)
if (_leftAligned)
{
m_context << Instruction::DUP1;
rightShiftNumberOnStack(64 + 32);
// <input> <address>
m_context << Instruction::SWAP1;
rightShiftNumberOnStack(64);
}
else
{
m_context << Instruction::DUP1;
rightShiftNumberOnStack(32);
m_context << ((u256(1) << 160) - 1) << Instruction::AND << Instruction::SWAP1;
}
m_context << u256(0xffffffffUL) << Instruction::AND;
}
void CompilerUtils::combineExternalFunctionType(bool _leftAligned)
{
// <address> <function_id>
m_context << u256(0xffffffffUL) << Instruction::AND << Instruction::SWAP1;
if (!_leftAligned)
m_context << ((u256(1) << 160) - 1) << Instruction::AND;
leftShiftNumberOnStack(32);
m_context << Instruction::OR;
if (_leftAligned)
leftShiftNumberOnStack(64);
}
void CompilerUtils::pushCombinedFunctionEntryLabel(Declaration const& _function, bool _runtimeOnly)
{
m_context << m_context.functionEntryLabel(_function).pushTag();
// If there is a runtime context, we have to merge both labels into the same
// stack slot in case we store it in storage.
if (CompilerContext* rtc = m_context.runtimeContext())
{
leftShiftNumberOnStack(32);
if (_runtimeOnly)
m_context <<
rtc->functionEntryLabel(_function).toSubAssemblyTag(m_context.runtimeSub()) <<
Instruction::OR;
}
}
void CompilerUtils::convertType(
Type const& _typeOnStack,
Type const& _targetType,
bool _cleanupNeeded,
bool _chopSignBits,
bool _asPartOfArgumentDecoding
)
{
// For a type extension, we need to remove all higher-order bits that we might have ignored in
// previous operations.
// @todo: store in the AST whether the operand might have "dirty" higher order bits
if (_typeOnStack == _targetType && !_cleanupNeeded)
return;
Type::Category stackTypeCategory = _typeOnStack.category();
Type::Category targetTypeCategory = _targetType.category();
if (auto contrType = dynamic_cast<ContractType const*>(&_typeOnStack))
solAssert(!contrType->isSuper(), "Cannot convert magic variable \"super\"");
bool enumOverflowCheckPending = (targetTypeCategory == Type::Category::Enum || stackTypeCategory == Type::Category::Enum);
bool chopSignBitsPending = _chopSignBits && targetTypeCategory == Type::Category::Integer;
if (chopSignBitsPending)
{
IntegerType const& targetIntegerType = dynamic_cast<IntegerType const&>(_targetType);
chopSignBitsPending = targetIntegerType.isSigned();
}
if (targetTypeCategory == Type::Category::FixedPoint)
solUnimplemented("Not yet implemented - FixedPointType.");
switch (stackTypeCategory)
{
case Type::Category::FixedBytes:
{
FixedBytesType const& typeOnStack = dynamic_cast<FixedBytesType const&>(_typeOnStack);
if (targetTypeCategory == Type::Category::Integer)
{
// conversion from bytes to integer. no need to clean the high bit
// only to shift right because of opposite alignment
IntegerType const& targetIntegerType = dynamic_cast<IntegerType const&>(_targetType);
rightShiftNumberOnStack(256 - typeOnStack.numBytes() * 8);
if (targetIntegerType.numBits() < typeOnStack.numBytes() * 8)
convertType(IntegerType(typeOnStack.numBytes() * 8), _targetType, _cleanupNeeded);
}
else if (targetTypeCategory == Type::Category::Address)
{
solAssert(typeOnStack.numBytes() * 8 == 160, "");
rightShiftNumberOnStack(256 - 160);
}
else
{
// clear for conversion to longer bytes
solAssert(targetTypeCategory == Type::Category::FixedBytes, "Invalid type conversion requested.");
FixedBytesType const& targetType = dynamic_cast<FixedBytesType const&>(_targetType);
if (typeOnStack.numBytes() == 0 || targetType.numBytes() == 0)
m_context << Instruction::POP << u256(0);
else if (targetType.numBytes() > typeOnStack.numBytes() || _cleanupNeeded)
{
unsigned bytes = min(typeOnStack.numBytes(), targetType.numBytes());
m_context << ((u256(1) << (256 - bytes * 8)) - 1);
m_context << Instruction::NOT << Instruction::AND;
}
}
break;
}
case Type::Category::Enum:
solAssert(_targetType == _typeOnStack || targetTypeCategory == Type::Category::Integer, "");
if (enumOverflowCheckPending)
{
EnumType const& enumType = dynamic_cast<decltype(enumType)>(_typeOnStack);
solAssert(enumType.numberOfMembers() > 0, "empty enum should have caused a parser error.");
m_context << u256(enumType.numberOfMembers() - 1) << Instruction::DUP2 << Instruction::GT;
if (_asPartOfArgumentDecoding)
m_context.appendConditionalRevert(false, "Enum out of range");
else
m_context.appendConditionalInvalid();
enumOverflowCheckPending = false;
}
break;
case Type::Category::FixedPoint:
solUnimplemented("Not yet implemented - FixedPointType.");
case Type::Category::Address:
case Type::Category::Integer:
case Type::Category::Contract:
case Type::Category::RationalNumber:
if (targetTypeCategory == Type::Category::FixedBytes)
{
solAssert(
stackTypeCategory == Type::Category::Address ||
stackTypeCategory == Type::Category::Integer ||
stackTypeCategory == Type::Category::RationalNumber,
"Invalid conversion to FixedBytesType requested."
);
// conversion from bytes to string. no need to clean the high bit
// only to shift left because of opposite alignment
FixedBytesType const& targetBytesType = dynamic_cast<FixedBytesType const&>(_targetType);
if (auto typeOnStack = dynamic_cast<IntegerType const*>(&_typeOnStack))
{
if (targetBytesType.numBytes() * 8 > typeOnStack->numBits())
cleanHigherOrderBits(*typeOnStack);
}
else if (stackTypeCategory == Type::Category::Address)
solAssert(targetBytesType.numBytes() * 8 == 160, "");
leftShiftNumberOnStack(256 - targetBytesType.numBytes() * 8);
}
else if (targetTypeCategory == Type::Category::Enum)
{
solAssert(stackTypeCategory != Type::Category::Address, "Invalid conversion to EnumType requested.");
solAssert(_typeOnStack.mobileType(), "");
// just clean
convertType(_typeOnStack, *_typeOnStack.mobileType(), true);
EnumType const& enumType = dynamic_cast<decltype(enumType)>(_targetType);
solAssert(enumType.numberOfMembers() > 0, "empty enum should have caused a parser error.");
m_context << u256(enumType.numberOfMembers() - 1) << Instruction::DUP2 << Instruction::GT;
m_context.appendConditionalInvalid();
enumOverflowCheckPending = false;
}
else if (targetTypeCategory == Type::Category::FixedPoint)
{
solAssert(
stackTypeCategory == Type::Category::Integer ||
stackTypeCategory == Type::Category::RationalNumber ||
stackTypeCategory == Type::Category::FixedPoint,
"Invalid conversion to FixedMxNType requested."
);
//shift all integer bits onto the left side of the fixed type
FixedPointType const& targetFixedPointType = dynamic_cast<FixedPointType const&>(_targetType);
if (auto typeOnStack = dynamic_cast<IntegerType const*>(&_typeOnStack))
if (targetFixedPointType.numBits() > typeOnStack->numBits())
cleanHigherOrderBits(*typeOnStack);
solUnimplemented("Not yet implemented - FixedPointType.");
}
else
{
solAssert(
targetTypeCategory == Type::Category::Integer ||
targetTypeCategory == Type::Category::Contract ||
targetTypeCategory == Type::Category::Address,
""
);
IntegerType addressType(160);
IntegerType const& targetType = targetTypeCategory == Type::Category::Integer
? dynamic_cast<IntegerType const&>(_targetType) : addressType;
if (stackTypeCategory == Type::Category::RationalNumber)
{
RationalNumberType const& constType = dynamic_cast<RationalNumberType const&>(_typeOnStack);
// We know that the stack is clean, we only have to clean for a narrowing conversion
// where cleanup is forced.
solUnimplementedAssert(!constType.isFractional(), "Not yet implemented - FixedPointType.");
if (targetType.numBits() < constType.integerType()->numBits() && _cleanupNeeded)
cleanHigherOrderBits(targetType);
}
else
{
IntegerType const& typeOnStack = stackTypeCategory == Type::Category::Integer
? dynamic_cast<IntegerType const&>(_typeOnStack) : addressType;
// Widening: clean up according to source type width
// Non-widening and force: clean up according to target type bits
if (targetType.numBits() > typeOnStack.numBits())
cleanHigherOrderBits(typeOnStack);
else if (_cleanupNeeded)
cleanHigherOrderBits(targetType);
if (chopSignBitsPending)
{
if (targetType.numBits() < 256)
m_context
<< ((u256(1) << targetType.numBits()) - 1)
<< Instruction::AND;
chopSignBitsPending = false;
}
}
}
break;
case Type::Category::StringLiteral:
{
auto const& literalType = dynamic_cast<StringLiteralType const&>(_typeOnStack);
string const& value = literalType.value();
bytesConstRef data(value);
if (targetTypeCategory == Type::Category::FixedBytes)
{
unsigned const numBytes = dynamic_cast<FixedBytesType const&>(_targetType).numBytes();
solAssert(data.size() <= 32, "");
m_context << (h256::Arith(h256(data, h256::AlignLeft)) & (~(u256(-1) >> (8 * numBytes))));
}
else if (targetTypeCategory == Type::Category::Array)
{
auto const& arrayType = dynamic_cast<ArrayType const&>(_targetType);
solAssert(arrayType.isByteArray(), "");
unsigned storageSize = 32 + ((data.size() + 31) / 32) * 32;
allocateMemory(storageSize);
// stack: mempos
m_context << Instruction::DUP1 << u256(data.size());
storeInMemoryDynamic(*TypeProvider::uint256());
// stack: mempos datapos
storeStringData(data);
}
else
solAssert(
false,
"Invalid conversion from string literal to " + _targetType.toString(false) + " requested."
);
break;
}
case Type::Category::Array:
{
solAssert(targetTypeCategory == stackTypeCategory, "");
ArrayType const& typeOnStack = dynamic_cast<ArrayType const&>(_typeOnStack);
ArrayType const& targetType = dynamic_cast<ArrayType const&>(_targetType);
switch (targetType.location())
{
case DataLocation::Storage:
// Other cases are done explicitly in LValue::storeValue, and only possible by assignment.
solAssert(
(targetType.isPointer() || (typeOnStack.isByteArray() && targetType.isByteArray())) &&
typeOnStack.location() == DataLocation::Storage,
"Invalid conversion to storage type."
);
break;
case DataLocation::Memory:
{
// Copy the array to a free position in memory, unless it is already in memory.
if (typeOnStack.location() != DataLocation::Memory)
{
// stack: <source ref> (variably sized)
unsigned stackSize = typeOnStack.sizeOnStack();
ArrayUtils(m_context).retrieveLength(typeOnStack);
// allocate memory
// stack: <source ref> (variably sized) <length>
m_context << Instruction::DUP1;
ArrayUtils(m_context).convertLengthToSize(targetType, true);
// stack: <source ref> (variably sized) <length> <size>
if (targetType.isDynamicallySized())
m_context << u256(0x20) << Instruction::ADD;
allocateMemory();
// stack: <source ref> (variably sized) <length> <mem start>
m_context << Instruction::DUP1;
moveIntoStack(2 + stackSize);
if (targetType.isDynamicallySized())
{
m_context << Instruction::DUP2;
storeInMemoryDynamic(*TypeProvider::uint256());
}
// stack: <mem start> <source ref> (variably sized) <length> <mem data pos>
if (targetType.baseType()->isValueType())
{
copyToStackTop(2 + stackSize, stackSize);
ArrayUtils(m_context).copyArrayToMemory(typeOnStack);
}
else
{
m_context << u256(0) << Instruction::SWAP1;
// stack: <mem start> <source ref> (variably sized) <length> <counter> <mem data pos>
auto repeat = m_context.newTag();