-
Notifications
You must be signed in to change notification settings - Fork 10.5k
/
Copy pathGenKeyPath.cpp
1378 lines (1225 loc) · 56.3 KB
/
GenKeyPath.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
//===--- GenKeyPath.cpp - IRGen support for key path objects --------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file contains code for emitting key path patterns, which can be used
// by the standard library to instantiate key path objects.
//
//===----------------------------------------------------------------------===//
#include "GenKeyPath.h"
#include "Callee.h"
#include "ClassLayout.h"
#include "ConstantBuilder.h"
#include "Explosion.h"
#include "GenClass.h"
#include "GenDecl.h"
#include "GenMeta.h"
#include "GenPointerAuth.h"
#include "GenProto.h"
#include "GenStruct.h"
#include "GenTuple.h"
#include "GenType.h"
#include "GenericRequirement.h"
#include "IRGenDebugInfo.h"
#include "IRGenFunction.h"
#include "IRGenMangler.h"
#include "IRGenModule.h"
#include "LoadableTypeInfo.h"
#include "MetadataLayout.h"
#include "ProtocolInfo.h"
#include "StructLayout.h"
#include "TypeInfo.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Function.h"
#include "swift/SIL/SILInstruction.h"
#include "swift/SIL/SILLocation.h"
#include "swift/SIL/TypeLowering.h"
#include "swift/ABI/KeyPath.h"
#include "swift/ABI/HeapObject.h"
#include "swift/AST/ASTContext.h"
#include "swift/AST/Decl.h"
#include "swift/AST/DiagnosticEngine.h"
#include "swift/AST/DiagnosticsIRGen.h"
#include "swift/AST/GenericEnvironment.h"
#include "swift/AST/ParameterList.h"
#include "swift/AST/Types.h"
#include "swift/Basic/Assertions.h"
#include "swift/Basic/Statistic.h"
#include "swift/IRGen/Linking.h"
using namespace swift;
using namespace irgen;
#define DEBUG_TYPE "IRGen key paths"
STATISTIC(NumTrivialPropertyDescriptors, "# of trivial property descriptors");
STATISTIC(NumNonTrivialPropertyDescriptors, "# of nontrivial property descriptors");
enum KeyPathAccessor {
Getter,
Setter,
Equals,
Hash,
};
void
irgen::bindPolymorphicArgumentsFromComponentIndices(IRGenFunction &IGF,
GenericEnvironment *genericEnv,
ArrayRef<GenericRequirement> requirements,
llvm::Value *args,
llvm::Value *size,
bool hasSubscriptIndices) {
if (!genericEnv)
return;
// The generic environment is marshaled into the end of the component
// argument area inside the instance. Bind the generic information out of
// the buffer.
auto genericArgsSize = llvm::ConstantInt::get(IGF.IGM.SizeTy,
requirements.size() * IGF.IGM.getPointerSize().getValue());
auto genericArgsOffset = IGF.Builder.CreateSub(size, genericArgsSize);
args =
IGF.Builder.CreateInBoundsGEP(IGF.IGM.Int8Ty, args, genericArgsOffset);
bindFromGenericRequirementsBuffer(
IGF, requirements,
Address(args, IGF.IGM.Int8Ty, IGF.IGM.getPointerAlignment()),
MetadataState::Complete, genericEnv->getForwardingSubstitutionMap());
}
static llvm::Function *
getAccessorForComputedComponent(IRGenModule &IGM,
const KeyPathPatternComponent &component,
KeyPathAccessor whichAccessor) {
SILFunction *accessor;
switch (whichAccessor) {
case Getter:
accessor = component.getComputedPropertyGetter();
break;
case Setter:
accessor = component.getComputedPropertySetter();
break;
case Equals:
accessor = component.getSubscriptIndexEquals();
break;
case Hash:
accessor = component.getSubscriptIndexHash();
break;
}
// If the accessor is locally available, we can use it as is.
// If it's only externally available, we need a local thunk to relative-
// reference.
if (!isAvailableExternally(accessor->getLinkage()) &&
&IGM == IGM.IRGen.getGenModule(accessor)) {
return IGM.getAddrOfSILFunction(accessor, NotForDefinition);
}
const char *thunkName;
switch (whichAccessor) {
case Getter:
thunkName = "keypath_get";
break;
case Setter:
thunkName = "keypath_set";
break;
case Equals:
thunkName = "keypath_equals";
break;
case Hash:
thunkName = "keypath_hash";
break;
}
auto accessorFn = IGM.getAddrOfSILFunction(accessor, NotForDefinition);
auto accessorThunk = llvm::Function::Create(accessorFn->getFunctionType(),
llvm::GlobalValue::PrivateLinkage,
thunkName, IGM.getModule());
accessorThunk->setAttributes(IGM.constructInitialAttributes());
accessorThunk->setCallingConv(IGM.SwiftCC);
accessorThunk->setAttributes(accessorFn->getAttributes());
{
IRGenFunction IGF(IGM, accessorThunk);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, accessorThunk);
Explosion forwardedArgs = IGF.collectParameters();
auto fnPtr =
FunctionPointer::forDirect(IGM, accessorFn, /*secondaryValue*/ nullptr,
accessor->getLoweredFunctionType());
auto call = IGF.Builder.CreateCall(fnPtr, forwardedArgs.claimAll());
if (call->getType()->isVoidTy())
IGF.Builder.CreateRetVoid();
else
IGF.Builder.CreateRet(call);
}
return accessorThunk;
}
static llvm::Function *
getLayoutFunctionForComputedComponent(IRGenModule &IGM,
const KeyPathPatternComponent &component,
GenericEnvironment *genericEnv,
ArrayRef<GenericRequirement> requirements) {
// Generate a function that returns the expected size and alignment necessary
// to store captured generic context and subscript index arguments.
auto retTy = llvm::StructType::get(IGM.getLLVMContext(),
{IGM.SizeTy, IGM.SizeTy});
auto fnTy = llvm::FunctionType::get(
retTy, { IGM.Int8PtrTy }, /*vararg*/ false);
auto layoutFn = llvm::Function::Create(fnTy,
llvm::GlobalValue::PrivateLinkage, "keypath_get_arg_layout", IGM.getModule());
layoutFn->setAttributes(IGM.constructInitialAttributes());
layoutFn->setCallingConv(IGM.SwiftCC);
{
IRGenFunction IGF(IGM, layoutFn);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, layoutFn);
// Unmarshal the generic environment from the argument buffer.
auto parameters = IGF.collectParameters();
auto args = parameters.claimNext();
if (genericEnv) {
bindFromGenericRequirementsBuffer(
IGF, requirements,
Address(args, IGM.Int8Ty, IGF.IGM.getPointerAlignment()),
MetadataState::Complete, genericEnv->getForwardingSubstitutionMap());
}
// Run through the captured index types to determine the size and alignment
// needed. Start with pointer alignment for the generic environment.
llvm::Value *size = llvm::ConstantInt::get(IGM.SizeTy, 0);
llvm::Value *alignMask = llvm::ConstantInt::get(IGM.SizeTy, 0);
for (auto &index : component.getSubscriptIndices()) {
auto ty = genericEnv
? genericEnv->mapTypeIntoContext(IGM.getSILModule(), index.LoweredType)
: index.LoweredType;
auto &ti = IGM.getTypeInfo(ty);
auto indexSize = ti.getSize(IGF, ty);
auto indexAlign = ti.getAlignmentMask(IGF, ty);
auto notIndexAlign = IGF.Builder.CreateNot(indexAlign);
size = IGF.Builder.CreateAdd(size, indexAlign);
size = IGF.Builder.CreateAnd(size, notIndexAlign);
size = IGF.Builder.CreateAdd(size, indexSize);
alignMask = IGF.Builder.CreateOr(alignMask, indexAlign);
}
// If there's generic environment to capture, then it's stored as a block
// of pointer-aligned words after the captured values.
auto genericsSize = llvm::ConstantInt::get(IGM.SizeTy,
IGM.getPointerSize().getValue() * requirements.size());
auto genericsAlign = llvm::ConstantInt::get(IGM.SizeTy,
IGM.getPointerAlignment().getValue() - 1);
auto notGenericsAlign = llvm::ConstantExpr::getNot(genericsAlign);
size = IGF.Builder.CreateAdd(size, genericsAlign);
size = IGF.Builder.CreateAnd(size, notGenericsAlign);
size = IGF.Builder.CreateAdd(size, genericsSize);
alignMask = IGF.Builder.CreateOr(alignMask, genericsAlign);
llvm::Value *retValue = IGF.Builder.CreateInsertValue(
llvm::UndefValue::get(retTy), size, 0);
retValue = IGF.Builder.CreateInsertValue(
retValue, alignMask, 1);
IGF.Builder.CreateRet(retValue);
}
return layoutFn;
}
static llvm::Constant *
getWitnessTableForComputedComponent(IRGenModule &IGM,
const KeyPathPatternComponent &component,
GenericEnvironment *genericEnv,
ArrayRef<GenericRequirement> requirements) {
// If the only thing we're capturing is generic environment, then we can
// use a prefab witness table from the runtime. A null reference will be
// filled in by the runtime.
if (component.getSubscriptIndices().empty()) {
return nullptr;
}
// Are the index values trivial?
bool isTrivial = true;
for (auto &component : component.getSubscriptIndices()) {
auto ty = genericEnv
? genericEnv->mapTypeIntoContext(IGM.getSILModule(), component.LoweredType)
: component.LoweredType;
auto &ti = IGM.getTypeInfo(ty);
isTrivial &= ti.isTriviallyDestroyable(ResilienceExpansion::Minimal);
}
llvm::Constant *destroy = nullptr;
llvm::Constant *copy;
if (isTrivial) {
// We can use prefab witnesses for handling trivial copying and destruction.
// A null destructor witness signals that the payload is trivial.
copy = IGM.getCopyKeyPathTrivialIndicesFn();
} else {
// Generate a destructor for this set of indices.
{
auto destroyType = llvm::FunctionType::get(IGM.VoidTy,
{IGM.Int8PtrTy, IGM.SizeTy},
/*vararg*/ false);
auto destroyFn = llvm::Function::Create(destroyType,
llvm::GlobalValue::PrivateLinkage, "keypath_destroy", IGM.getModule());
destroy = destroyFn;
destroyFn->setAttributes(IGM.constructInitialAttributes());
destroyFn->setCallingConv(IGM.SwiftCC);
IRGenFunction IGF(IGM, destroyFn);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, destroyFn);
auto params = IGF.collectParameters();
auto componentArgsBuf = params.claimNext();
auto componentArgsBufSize = params.claimNext();
bindPolymorphicArgumentsFromComponentIndices(IGF,
genericEnv, requirements,
componentArgsBuf,
componentArgsBufSize,
!component.getSubscriptIndices().empty());
llvm::Value *offset = nullptr;
for (auto &component : component.getSubscriptIndices()) {
auto ty = genericEnv
? genericEnv->mapTypeIntoContext(IGM.getSILModule(),
component.LoweredType)
: component.LoweredType;
auto &ti = IGM.getTypeInfo(ty);
if (offset) {
auto align = ti.getAlignmentMask(IGF, ty);
auto notAlign = IGF.Builder.CreateNot(align);
offset = IGF.Builder.CreateAdd(offset, align);
offset = IGF.Builder.CreateAnd(offset, notAlign);
} else {
offset = llvm::ConstantInt::get(IGM.SizeTy, 0);
}
auto elt =
IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, componentArgsBuf, offset);
auto eltAddr = ti.getAddressForPointer(
IGF.Builder.CreateBitCast(elt, ti.getStorageType()->getPointerTo()));
ti.destroy(IGF, eltAddr, ty,
true /*witness table: need it to be fast*/);
auto size = ti.getSize(IGF, ty);
offset = IGF.Builder.CreateAdd(offset, size);
}
IGF.Builder.CreateRetVoid();
}
// Generate a copier for this set of indices.
{
auto copyType = llvm::FunctionType::get(IGM.VoidTy,
{IGM.Int8PtrTy, IGM.Int8PtrTy,
IGM.SizeTy},
/*vararg*/ false);
auto copyFn = llvm::Function::Create(copyType,
llvm::GlobalValue::PrivateLinkage, "keypath_copy", IGM.getModule());
copy = copyFn;
copyFn->setAttributes(IGM.constructInitialAttributes());
copyFn->setCallingConv(IGM.SwiftCC);
IRGenFunction IGF(IGM, copyFn);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, copyFn);
auto params = IGF.collectParameters();
auto sourceArgsBuf = params.claimNext();
auto destArgsBuf = params.claimNext();
auto componentArgsBufSize = params.claimNext();
bindPolymorphicArgumentsFromComponentIndices(IGF,
genericEnv, requirements,
sourceArgsBuf,
componentArgsBufSize,
!component.getSubscriptIndices().empty());
// Copy over the index values.
llvm::Value *offset = nullptr;
for (auto &component : component.getSubscriptIndices()) {
auto ty = genericEnv
? genericEnv->mapTypeIntoContext(IGM.getSILModule(),
component.LoweredType)
: component.LoweredType;
auto &ti = IGM.getTypeInfo(ty);
if (offset) {
auto align = ti.getAlignmentMask(IGF, ty);
auto notAlign = IGF.Builder.CreateNot(align);
offset = IGF.Builder.CreateAdd(offset, align);
offset = IGF.Builder.CreateAnd(offset, notAlign);
} else {
offset = llvm::ConstantInt::get(IGM.SizeTy, 0);
}
auto sourceElt =
IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, sourceArgsBuf, offset);
auto destElt =
IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, destArgsBuf, offset);
auto sourceEltAddr = ti.getAddressForPointer(
IGF.Builder.CreateBitCast(sourceElt,
ti.getStorageType()->getPointerTo()));
auto destEltAddr = ti.getAddressForPointer(
IGF.Builder.CreateBitCast(destElt,
ti.getStorageType()->getPointerTo()));
ti.initializeWithCopy(IGF, destEltAddr, sourceEltAddr, ty, false);
auto size = ti.getSize(IGF, ty);
offset = IGF.Builder.CreateAdd(offset, size);
}
// Copy over the generic environment.
if (genericEnv) {
auto envAlignMask = llvm::ConstantInt::get(IGM.SizeTy,
IGM.getPointerAlignment().getMaskValue());
auto notAlignMask = IGF.Builder.CreateNot(envAlignMask);
offset = IGF.Builder.CreateAdd(offset, envAlignMask);
offset = IGF.Builder.CreateAnd(offset, notAlignMask);
auto sourceEnv =
IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, sourceArgsBuf, offset);
auto destEnv =
IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, destArgsBuf, offset);
auto align = IGM.getPointerAlignment().getValue();
IGF.Builder.CreateMemCpy(destEnv, llvm::MaybeAlign(align), sourceEnv,
llvm::MaybeAlign(align),
IGM.getPointerSize().getValue() *
requirements.size());
}
IGF.Builder.CreateRetVoid();
}
}
auto equals = getAccessorForComputedComponent(IGM, component, Equals);
auto hash = getAccessorForComputedComponent(IGM, component, Hash);
ConstantInitBuilder builder(IGM);
ConstantStructBuilder fields = builder.beginStruct();
auto schemaKeyPath = IGM.getOptions().PointerAuth.KeyPaths;
if (destroy)
fields.addSignedPointer(destroy, schemaKeyPath,
PointerAuthEntity::Special::KeyPathDestroy);
else
fields.addNullPointer(IGM.FunctionPtrTy);
fields.addSignedPointer(copy, schemaKeyPath,
PointerAuthEntity::Special::KeyPathCopy);
fields.addSignedPointer(equals, schemaKeyPath,
PointerAuthEntity::Special::KeyPathEquals);
fields.addSignedPointer(hash, schemaKeyPath,
PointerAuthEntity::Special::KeyPathHash);
return fields.finishAndCreateGlobal(
"keypath_witnesses", IGM.getPointerAlignment(), /*constant*/ true,
llvm::GlobalVariable::PrivateLinkage);
}
/// Information about each index operand for a key path pattern that is used
/// to lay out and consume the argument packet.
struct KeyPathIndexOperand {
SILType LoweredType;
const KeyPathPatternComponent *LastUser;
};
static llvm::Function *
getInitializerForComputedComponent(IRGenModule &IGM,
const KeyPathPatternComponent &component,
ArrayRef<KeyPathIndexOperand> operands,
GenericEnvironment *genericEnv,
ArrayRef<GenericRequirement> requirements) {
auto fnTy = llvm::FunctionType::get(IGM.VoidTy,
{ /*src*/ IGM.Int8PtrTy,
/*dest*/ IGM.Int8PtrTy }, /*vararg*/ false);
auto initFn = llvm::Function::Create(fnTy,
llvm::GlobalValue::PrivateLinkage, "keypath_arg_init", IGM.getModule());
initFn->setAttributes(IGM.constructInitialAttributes());
initFn->setCallingConv(IGM.SwiftCC);
{
IRGenFunction IGF(IGM, initFn);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, initFn);
auto params = IGF.collectParameters();
// Pointer to the argument packet passed into swift_getKeyPath
auto src = params.claimNext();
// Pointer to the destination component's argument buffer
auto dest = params.claimNext();
SmallVector<Address, 4> srcAddresses;
int lastOperandNeeded = -1;
for (auto &index : component.getSubscriptIndices()) {
lastOperandNeeded = std::max(lastOperandNeeded, (int)index.Operand);
}
llvm::Value *offset;
if (genericEnv) {
// We'll copy over the generic environment after we copy in the indexes.
offset = llvm::ConstantInt::get(IGM.SizeTy,
IGM.getPointerSize().getValue() * requirements.size());
// Bind the generic environment from the argument buffer.
bindFromGenericRequirementsBuffer(
IGF, requirements,
Address(src, IGM.Int8Ty, IGF.IGM.getPointerAlignment()),
MetadataState::Complete, genericEnv->getForwardingSubstitutionMap());
} else {
offset = llvm::ConstantInt::get(IGM.SizeTy, 0);
}
// Figure out the offsets of the operands in the source buffer.
for (int i = 0; i <= lastOperandNeeded; ++i) {
auto ty = genericEnv
? genericEnv->mapTypeIntoContext(IGM.getSILModule(),
operands[i].LoweredType)
: operands[i].LoweredType;
auto &ti = IGM.getTypeInfo(ty);
if (i != 0 || genericEnv) {
auto alignMask = ti.getAlignmentMask(IGF, ty);
auto notAlignMask = IGF.Builder.CreateNot(alignMask);
offset = IGF.Builder.CreateAdd(offset, alignMask);
offset = IGF.Builder.CreateAnd(offset, notAlignMask);
}
auto ptr = IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, src, offset);
auto addr = ti.getAddressForPointer(IGF.Builder.CreateBitCast(
ptr, ti.getStorageType()->getPointerTo()));
srcAddresses.push_back(addr);
auto size = ti.getSize(IGF, ty);
offset = IGF.Builder.CreateAdd(offset, size);
}
offset = llvm::ConstantInt::get(IGM.SizeTy, 0);
// Transfer the operands we want into the destination buffer.
for (unsigned i : indices(component.getSubscriptIndices())) {
auto &index = component.getSubscriptIndices()[i];
auto ty = genericEnv
? genericEnv->mapTypeIntoContext(IGM.getSILModule(),
index.LoweredType)
: index.LoweredType;
auto &ti = IGM.getTypeInfo(ty);
if (i != 0) {
auto alignMask = ti.getAlignmentMask(IGF, ty);
auto notAlignMask = IGF.Builder.CreateNot(alignMask);
offset = IGF.Builder.CreateAdd(offset, alignMask);
offset = IGF.Builder.CreateAnd(offset, notAlignMask);
}
auto ptr = IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, dest, offset);
auto destAddr = ti.getAddressForPointer(IGF.Builder.CreateBitCast(
ptr, ti.getStorageType()->getPointerTo()));
// The last component using an operand can move the value out of the
// buffer.
if (&component == operands[index.Operand].LastUser) {
ti.initializeWithTake(IGF, destAddr, srcAddresses[index.Operand], ty,
false, /*zeroizeIfSensitive=*/ true);
} else {
ti.initializeWithCopy(IGF, destAddr, srcAddresses[index.Operand], ty,
false);
}
auto size = ti.getSize(IGF, ty);
offset = IGF.Builder.CreateAdd(offset, size);
}
// Transfer the generic environment.
// External components don't need to store the key path environment (and
// can't), since they need to already have enough information to function
// independently of any context using the component.
if (genericEnv) {
auto destGenericEnv = dest;
if (!component.getSubscriptIndices().empty()) {
auto genericEnvAlignMask = llvm::ConstantInt::get(IGM.SizeTy,
IGM.getPointerAlignment().getMaskValue());
auto notGenericEnvAlignMask = IGF.Builder.CreateNot(genericEnvAlignMask);
offset = IGF.Builder.CreateAdd(offset, genericEnvAlignMask);
offset = IGF.Builder.CreateAnd(offset, notGenericEnvAlignMask);
destGenericEnv =
IGF.Builder.CreateInBoundsGEP(IGM.Int8Ty, dest, offset);
}
auto align = IGM.getPointerAlignment().getValue();
IGF.Builder.CreateMemCpy(
destGenericEnv, llvm::MaybeAlign(align), src, llvm::MaybeAlign(align),
IGM.getPointerSize().getValue() * requirements.size());
}
IGF.Builder.CreateRetVoid();
}
return initFn;
}
static llvm::Constant *
emitMetadataTypeRefForKeyPath(IRGenModule &IGM, CanType type,
CanGenericSignature sig) {
// Produce a mangled name for the type.
auto constant = IGM.getTypeRef(type, sig, MangledTypeRefRole::Metadata).first;
// Mask the bottom bit to tell the key path runtime this is a mangled name
// rather than a direct reference.
auto bitConstant = llvm::ConstantInt::get(IGM.IntPtrTy, 1);
return llvm::ConstantExpr::getGetElementPtr(IGM.Int8Ty, constant,
bitConstant);
}
static unsigned getClassFieldIndex(ClassDecl *classDecl, VarDecl *property) {
SmallVector<ClassDecl *, 3> superclasses;
for (auto *superDecl = classDecl; superDecl != nullptr;
superDecl = superDecl->getSuperclassDecl()) {
superclasses.push_back(superDecl);
}
std::reverse(superclasses.begin(), superclasses.end());
unsigned index = 0;
for (auto *superDecl : superclasses) {
for (auto *other : superDecl->getStoredProperties()) {
if (other == property)
return index;
++index;
}
}
llvm_unreachable("Did not find stored property in class");
}
static void
emitKeyPathComponent(IRGenModule &IGM,
ConstantStructBuilder &fields,
const KeyPathPatternComponent &component,
bool isInstantiableOnce,
GenericEnvironment *genericEnv,
ArrayRef<GenericRequirement> requirements,
CanType baseTy,
ArrayRef<KeyPathIndexOperand> operands,
bool hasSubscriptIndices) {
assert(fields.getNextOffsetFromGlobal() % Alignment(4) == Size(0)
&& "must be 32-bit-aligned here");
SILType loweredBaseTy;
loweredBaseTy = IGM.getLoweredType(AbstractionPattern::getOpaque(),
baseTy->getWithoutSpecifierType());
// TODO: Eliminate GenericContextScope entirely
GenericContextScope scope(
IGM, genericEnv
? genericEnv->getGenericSignature().getCanonicalSignature()
: nullptr);
switch (auto kind = component.getKind()) {
case KeyPathPatternComponent::Kind::StoredProperty: {
auto property = cast<VarDecl>(component.getStoredPropertyDecl());
auto addFixedOffset = [&](bool isStruct, bool isLet,
llvm::Constant *offset) {
if (auto offsetInt = dyn_cast_or_null<llvm::ConstantInt>(offset)) {
auto offsetValue = offsetInt->getValue().getZExtValue();
if (KeyPathComponentHeader::offsetCanBeInline(offsetValue)) {
auto header = isStruct
? KeyPathComponentHeader
::forStructComponentWithInlineOffset(isLet, offsetValue)
: KeyPathComponentHeader
::forClassComponentWithInlineOffset(isLet, offsetValue);
fields.addInt32(header.getData());
return;
}
}
auto header = isStruct
? KeyPathComponentHeader::forStructComponentWithOutOfLineOffset(isLet)
: KeyPathComponentHeader::forClassComponentWithOutOfLineOffset(isLet);
fields.addInt32(header.getData());
fields.add(llvm::ConstantExpr::getTruncOrBitCast(offset, IGM.Int32Ty));
};
// For a struct stored property, we may know the fixed offset of the field,
// or we may need to fetch it out of the type's metadata at instantiation
// time.
if (auto theStruct = loweredBaseTy.getStructOrBoundGenericStruct()) {
if (auto offset = emitPhysicalStructMemberFixedOffset(IGM,
loweredBaseTy,
property)) {
// We have a known constant fixed offset.
addFixedOffset(/*struct*/ true, property->isLet(), offset);
break;
}
// If the offset isn't fixed, try instead to get the field offset out
// of the type metadata at instantiation time.
auto &metadataLayout = IGM.getMetadataLayout(theStruct);
auto fieldOffset = metadataLayout.getStaticFieldOffset(property);
auto header = KeyPathComponentHeader
::forStructComponentWithUnresolvedFieldOffset(property->isLet());
fields.addInt32(header.getData());
fields.addInt32(fieldOffset.getValue());
break;
}
auto *classDecl = baseTy->getClassOrBoundGenericClass();
auto loweredClassTy = loweredBaseTy;
// Recover class decl from superclass constraint
if (!classDecl && genericEnv) {
auto ty = genericEnv->mapTypeIntoContext(baseTy)->getCanonicalType();
auto archetype = dyn_cast<ArchetypeType>(ty);
if (archetype && archetype->requiresClass()) {
auto superClassTy = ty->getSuperclass(false)->getCanonicalType();
classDecl = superClassTy->getClassOrBoundGenericClass();
loweredClassTy =
IGM.getLoweredType(AbstractionPattern::getOpaque(),
superClassTy->getWithoutSpecifierType());
}
}
// For a class, we may know the fixed offset of a field at compile time,
// or we may need to fetch it at instantiation time. Depending on the
// ObjC-ness and resilience of the class hierarchy, there might be a few
// different ways we need to go about this.
if (loweredClassTy.getClassOrBoundGenericClass()) {
// Use the property's class type to determine the field access.
auto propertyBaseDecl = property->getDeclContext()->getSelfClassDecl();
auto currentBaseTy =
loweredClassTy.getASTType()->getSuperclassForDecl(propertyBaseDecl);
assert(currentBaseTy->getClassOrBoundGenericClass() == propertyBaseDecl);
loweredClassTy =
IGM.getLoweredType(AbstractionPattern::getOpaque(), currentBaseTy);
auto loweredBaseContextTy =
SILType::getPrimitiveObjectType(loweredClassTy.getASTType());
if (!loweredClassTy.getASTType()->hasArchetype())
loweredBaseContextTy = SILType::getPrimitiveObjectType(
GenericEnvironment::mapTypeIntoContext(genericEnv,
loweredClassTy.getASTType())
->getCanonicalType());
switch (getClassFieldAccess(IGM, loweredBaseContextTy, property)) {
case FieldAccess::ConstantDirect: {
// Known compile-time constant field offset.
auto offset = tryEmitConstantClassFragilePhysicalMemberOffset(
IGM, loweredClassTy, property);
assert(offset && "no constant offset for ConstantDirect field?!");
addFixedOffset(/*struct*/ false, property->isLet(), offset);
break;
}
case FieldAccess::NonConstantDirect: {
// A constant offset that's determined at class realization time.
// We have to load the offset from a global ivar.
//
// This means the field offset is constant at runtime, but is not known
// at compile time.
auto header = KeyPathComponentHeader
::forClassComponentWithUnresolvedIndirectOffset(property->isLet());
fields.addInt32(header.getData());
auto offsetRef = IGM.getAddrOfLLVMVariableOrGOTEquivalent(
LinkEntity::forFieldOffset(property));
fields.addRelativeAddress(offsetRef);
break;
}
case FieldAccess::ConstantIndirect: {
// An offset that depends on the instance's generic parameterization,
// but whose field offset is at a known metadata offset.
auto header = KeyPathComponentHeader
::forClassComponentWithUnresolvedFieldOffset(property->isLet());
fields.addInt32(header.getData());
// FIXME: This doesn't support classes with resilient ancestry, because
// the offset into the metadata is itself not constant.
//
// SILGen emits the descriptor as a computed property in this case.
auto fieldOffset = getClassFieldOffsetOffset(
IGM, loweredClassTy.getClassOrBoundGenericClass(), property);
fields.addInt32(fieldOffset.getValue());
break;
}
}
break;
}
llvm_unreachable("not struct or class");
}
case KeyPathPatternComponent::Kind::GettableProperty:
case KeyPathPatternComponent::Kind::SettableProperty: {
// If the component references an external property, encode that in a
// header before the local attempt header, so that we can consult the
// external descriptor at instantiation time.
//
// Note that when compiling inlinable functions, we can have external
// declarations that point within the same module. Just ignore those.
auto externalDecl = component.getExternalDecl();
if (externalDecl &&
externalDecl->getModuleContext() != IGM.getSwiftModule()) {
SmallVector<llvm::Constant *, 4> externalSubArgs;
auto componentSig = externalDecl->getInnermostDeclContext()
->getGenericSignatureOfContext();
auto componentCanSig = componentSig.getCanonicalSignature();
auto subs = component.getExternalSubstitutions();
if (!subs.empty()) {
enumerateGenericSignatureRequirements(
componentCanSig, [&](GenericRequirement reqt) {
auto substType =
reqt.getTypeParameter().subst(subs)->getCanonicalType();
// FIXME: This seems wrong. We used to just mangle opened archetypes as
// their interface type. Let's make that explicit now.
substType = substType
.transformRec([](Type t) -> std::optional<Type> {
if (auto *openedExistential =
t->getAs<OpenedArchetypeType>())
return openedExistential->getInterfaceType();
return std::nullopt;
})
->getCanonicalType();
if (reqt.isAnyMetadata()) {
// Type requirement.
externalSubArgs.push_back(emitMetadataTypeRefForKeyPath(
IGM, substType, componentCanSig));
} else {
assert(reqt.isAnyWitnessTable());
// Protocol requirement.
auto conformance = subs.lookupConformance(
reqt.getTypeParameter()->getCanonicalType(),
reqt.getProtocol());
externalSubArgs.push_back(IGM.emitWitnessTableRefString(
substType, conformance,
genericEnv ? genericEnv->getGenericSignature() :
componentCanSig,
/*shouldSetLowBit*/ true));
}
});
}
fields.addInt32(
KeyPathComponentHeader::forExternalComponent(externalSubArgs.size())
.getData());
auto descriptor = IGM.getAddrOfLLVMVariableOrGOTEquivalent(
LinkEntity::forPropertyDescriptor(externalDecl));
fields.addRelativeAddress(descriptor);
for (auto *arg : externalSubArgs)
fields.addRelativeAddress(arg);
}
// Encode the settability.
bool settable = kind == KeyPathPatternComponent::Kind::SettableProperty;
bool mutating = settable && component.isComputedSettablePropertyMutating();
KeyPathComponentHeader::ComputedPropertyKind componentKind;
if (settable) {
componentKind = mutating
? KeyPathComponentHeader::SettableMutating
: KeyPathComponentHeader::SettableNonmutating;
} else {
componentKind = KeyPathComponentHeader::GetOnly;
}
// Lower the id reference.
auto id = component.getComputedPropertyId();
KeyPathComponentHeader::ComputedPropertyIDKind idKind;
llvm::Constant *idValue;
KeyPathComponentHeader::ComputedPropertyIDResolution idResolution;
switch (id.getKind()) {
case KeyPathPatternComponent::ComputedPropertyId::Function: {
idKind = KeyPathComponentHeader::Pointer;
// FIXME: Does this need to be signed?
auto idRef = IGM.getAddrOfLLVMVariableOrGOTEquivalent(
LinkEntity::forSILFunction(id.getFunction()));
idValue = idRef.getValue();
// If we got an indirect reference, we'll need to resolve it at
// instantiation time.
idResolution = idRef.isIndirect()
? KeyPathComponentHeader::IndirectPointer
// Compute absolute reference from relative reference if target supports it.
// Otherwise, embed absolute reference directly.
: (IGM.getOptions().CompactAbsoluteFunctionPointer
? KeyPathComponentHeader::ResolvedAbsolute
: KeyPathComponentHeader::Resolved);
break;
}
case KeyPathPatternComponent::ComputedPropertyId::DeclRef: {
auto declRef = id.getDeclRef();
// Foreign method refs identify using a selector
// reference, which is doubly-indirected and filled in with a unique
// pointer by dyld.
if (declRef.isForeign) {
assert(IGM.ObjCInterop && "foreign keypath component w/o objc interop?!");
idKind = KeyPathComponentHeader::Pointer;
// FIXME: In non-JIT mode, ideally we would just refer to the selector
// reference variable here with an indirectpointer resolution,
// but ld64 section coalescing on the __objc_sel section can break
// relative references (and on some platforms, mach-o just doesn't
// support the necessary relocations).
// As a workaround, generate a stub function to resolve the selector.
//
// Note that we'd need to do this anyway in JIT mode because we would
// need to unique the selector at runtime anyway.
auto selectorName = IGM.getObjCSelectorName(declRef);
SmallString<32> fnName;
fnName.append("keypath_get_selector_");
fnName.append(selectorName);
auto fn = IGM.getOrCreateHelperFunction(fnName, IGM.Int8PtrTy,
{IGM.Int8PtrTy},
[&selectorName](IRGenFunction &subIGF) {
auto selectorValue = subIGF.emitObjCSelectorRefLoad(selectorName);
subIGF.Builder.CreateRet(selectorValue);
});
idValue = fn;
idResolution = KeyPathComponentHeader::FunctionCall;
} else {
if (auto overridden = declRef.getOverriddenVTableEntry())
declRef = overridden;
if (auto overridden = declRef.getOverriddenWitnessTableEntry())
declRef = overridden;
auto dc = declRef.getDecl()->getDeclContext();
// We can use a method descriptor if we have a class or resilient
// protocol.
if (isa<ClassDecl>(dc) ||
IGM.isResilient(cast<NominalTypeDecl>(dc),
ResilienceExpansion::Minimal)) {
idKind = KeyPathComponentHeader::Pointer;
auto idRef = IGM.getAddrOfLLVMVariableOrGOTEquivalent(
LinkEntity::forMethodDescriptor(declRef));
idValue = idRef.getValue();
idResolution = idRef.isIndirect()
? KeyPathComponentHeader::IndirectPointer
: KeyPathComponentHeader::Resolved;
break;
}
idKind = KeyPathComponentHeader::VTableOffset;
auto methodProto = cast<ProtocolDecl>(dc);
auto &protoInfo = IGM.getProtocolInfo(methodProto,
ProtocolInfoKind::Full);
auto index = protoInfo.getFunctionIndex(declRef);
idValue = llvm::ConstantInt::get(IGM.SizeTy, -index.getValue());
idResolution = KeyPathComponentHeader::Resolved;
}
break;
}
case KeyPathPatternComponent::ComputedPropertyId::Property:
// Use the index of the stored property within the aggregate to key
// the property.
auto property = id.getProperty();
idKind = KeyPathComponentHeader::StoredPropertyIndex;
auto *classDecl = baseTy->getClassOrBoundGenericClass();
auto loweredClassTy = loweredBaseTy;
// Recover class decl from superclass constraint
if (!classDecl && genericEnv) {
auto ty = genericEnv->mapTypeIntoContext(baseTy)->getCanonicalType();
auto archetype = dyn_cast<ArchetypeType>(ty);
if (archetype && archetype->requiresClass()) {
auto superClassTy = ty->getSuperclass(false)->getCanonicalType();
classDecl = superClassTy->getClassOrBoundGenericClass();
loweredClassTy =
IGM.getLoweredType(AbstractionPattern::getOpaque(),
superClassTy->getWithoutSpecifierType());
}
}
if (auto struc = baseTy->getStructOrBoundGenericStruct()) {
// Scan the stored properties of the struct to find the index. We should
// only ever use a struct field as a uniquing key from inside the
// struct's own module, so this is OK.
idResolution = KeyPathComponentHeader::Resolved;
std::optional<unsigned> structIdx;
unsigned i = 0;
for (auto storedProp : struc->getStoredProperties()) {
if (storedProp == property) {
structIdx = i;
break;
}
++i;
}
assert(structIdx && "not a stored property of the struct?!");
idValue = llvm::ConstantInt::get(IGM.SizeTy, structIdx.value());
} else if (classDecl) {
// TODO: This field index would require runtime resolution with Swift
// native class resilience. We never directly access ObjC-imported
// ivars so we can disregard ObjC ivar resilience for this computation
// and start counting at the Swift native root.
if (loweredClassTy.getASTType()->hasTypeParameter())
loweredClassTy = SILType::getPrimitiveObjectType(
GenericEnvironment::mapTypeIntoContext(
genericEnv, loweredClassTy.getASTType())
->getCanonicalType());
switch (getClassFieldAccess(IGM, loweredClassTy, property)) {
case FieldAccess::ConstantDirect:
case FieldAccess::ConstantIndirect:
case FieldAccess::NonConstantDirect:
idResolution = KeyPathComponentHeader::Resolved;
idValue = llvm::ConstantInt::get(IGM.SizeTy,
getClassFieldIndex(classDecl, property));
break;
}
} else {
llvm_unreachable("neither struct nor class");
}
break;
}
auto header = KeyPathComponentHeader::forComputedProperty(componentKind,
idKind, !isInstantiableOnce, idResolution);
fields.addInt32(header.getData());
switch (idKind) {
case KeyPathComponentHeader::Pointer:
// Use a relative offset to the referent if value is not absolute.
if (idResolution == KeyPathComponentHeader::ResolvedAbsolute) {
fields.add(idValue);
} else {
fields.addRelativeAddress(idValue);
}
break;
case KeyPathComponentHeader::VTableOffset:
case KeyPathComponentHeader::StoredPropertyIndex:
// Store the offset as an i32.