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CodaFiCodaFi
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Merge pull request #37359 from CodaFi/one-definition-to-rule-them-all
Undo Force Load + Incremental Ban on Darwin Platforms
2 parents fbdb140 + f6b2294 commit cb319fc

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18 files changed

+125
-89
lines changed

18 files changed

+125
-89
lines changed

‎include/swift/AST/DiagnosticsDriver.def‎

Lines changed: 0 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -119,9 +119,6 @@ ERROR(error_input_changed_during_build,none,
119119
ERROR(error_conflicting_options, none,
120120
"conflicting options '%0' and '%1'",
121121
(StringRef, StringRef))
122-
ERROR(error_option_not_supported, none,
123-
"'%0' is not supported with '%1'",
124-
(StringRef, StringRef))
125122
ERROR(error_requirement_not_met, none,
126123
"'%0' requires '%1'",
127124
(StringRef, StringRef))

‎include/swift/IRGen/Linking.h‎

Lines changed: 1 addition & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -1417,6 +1417,7 @@ struct IRLinkage {
14171417
static const IRLinkage InternalWeakODR;
14181418
static const IRLinkage Internal;
14191419

1420+
static const IRLinkage ExternalCommon;
14201421
static const IRLinkage ExternalImport;
14211422
static const IRLinkage ExternalWeakImport;
14221423
static const IRLinkage ExternalExport;

‎lib/Driver/Driver.cpp‎

Lines changed: 0 additions & 22 deletions
Original file line numberDiff line numberDiff line change
@@ -251,27 +251,6 @@ static void validateSearchPathArgs(DiagnosticEngine &diags,
251251
}
252252
}
253253

254-
static void validateAutolinkingArgs(DiagnosticEngine &diags,
255-
const ArgList &args,
256-
const llvm::Triple &T) {
257-
auto *forceLoadArg = args.getLastArg(options::OPT_autolink_force_load);
258-
if (!forceLoadArg)
259-
return;
260-
auto *incrementalArg = args.getLastArg(options::OPT_incremental);
261-
if (!incrementalArg)
262-
return;
263-
264-
if (T.supportsCOMDAT())
265-
return;
266-
267-
// Note: -incremental can itself be overridden by other arguments later
268-
// on, but since -autolink-force-load is a rare and not-really-recommended
269-
// option it's not worth modeling that complexity here (or moving the
270-
// check somewhere else).
271-
diags.diagnose(SourceLoc(), diag::error_option_not_supported,
272-
forceLoadArg->getSpelling(), incrementalArg->getSpelling());
273-
}
274-
275254
/// Perform miscellaneous early validation of arguments.
276255
static void validateArgs(DiagnosticEngine &diags, const ArgList &args,
277256
const llvm::Triple &T) {
@@ -282,7 +261,6 @@ static void validateArgs(DiagnosticEngine &diags, const ArgList &args,
282261
validateDebugInfoArgs(diags, args);
283262
validateCompilationConditionArgs(diags, args);
284263
validateSearchPathArgs(diags, args);
285-
validateAutolinkingArgs(diags, args, T);
286264
validateVerifyIncrementalDependencyArgs(diags, args);
287265
}
288266

‎lib/FrontendTool/TBD.cpp‎

Lines changed: 2 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -84,7 +84,8 @@ static bool validateSymbols(DiagnosticEngine &diags,
8484
if (auto GV = dyn_cast<llvm::GlobalValue>(value)) {
8585
// Is this a symbol that should be listed?
8686
auto externallyVisible =
87-
GV->hasExternalLinkage() && !GV->hasHiddenVisibility();
87+
(GV->hasExternalLinkage() || GV->hasCommonLinkage())
88+
&& !GV->hasHiddenVisibility();
8889
if (!GV->isDeclaration() && externallyVisible) {
8990
// Is it listed?
9091
if (!symbolSet.erase(name))

‎lib/IRGen/IRGenModule.cpp‎

Lines changed: 43 additions & 29 deletions
Original file line numberDiff line numberDiff line change
@@ -1300,18 +1300,6 @@ static bool replaceModuleFlagsEntry(llvm::LLVMContext &Ctx,
13001300
llvm_unreachable("Could not replace old linker options entry?");
13011301
}
13021302

1303-
/// Returns true if the object file generated by \p IGM will be the "first"
1304-
/// object file in the module. This lets us determine where to put a symbol
1305-
/// that must be unique.
1306-
static bool isFirstObjectFileInModule(IRGenModule &IGM) {
1307-
if (IGM.getSILModule().isWholeModule())
1308-
return IGM.IRGen.getPrimaryIGM() == &IGM;
1309-
1310-
auto *file = cast<FileUnit>(IGM.getSILModule().getAssociatedContext());
1311-
auto *containingModule = file->getParentModule();
1312-
return containingModule->getFiles().front() == file;
1313-
}
1314-
13151303
static bool
13161304
doesTargetAutolinkUsingAutolinkExtract(const SwiftTargetInfo &TargetInfo,
13171305
const llvm::Triple &Triple) {
@@ -1486,6 +1474,47 @@ AutolinkKind AutolinkKind::create(const SwiftTargetInfo &TargetInfo,
14861474
return AutolinkKind::LLVMLinkerOptions;
14871475
}
14881476

1477+
static llvm::GlobalObject *createForceImportThunk(IRGenModule &IGM) {
1478+
llvm::SmallString<64> buf;
1479+
encodeForceLoadSymbolName(buf, IGM.IRGen.Opts.ForceLoadSymbolName);
1480+
if (IGM.Triple.isOSBinFormatMachO()) {
1481+
// On Mach-O targets, emit a common force-load symbol that resolves to
1482+
// a global variable so it will be coalesced at static link time into a
1483+
// single external symbol.
1484+
//
1485+
// Looks like C's tentative definitions are good for something after all.
1486+
auto ForceImportThunk =
1487+
new llvm::GlobalVariable(IGM.Module,
1488+
IGM.Int1Ty,
1489+
/*isConstant=*/false,
1490+
llvm::GlobalValue::CommonLinkage,
1491+
llvm::Constant::getNullValue(IGM.Int1Ty),
1492+
buf.str());
1493+
ApplyIRLinkage(IRLinkage::ExternalCommon).to(ForceImportThunk);
1494+
IGM.addUsedGlobal(ForceImportThunk);
1495+
return ForceImportThunk;
1496+
} else {
1497+
// On all other targets, emit an external symbol that resolves to a
1498+
// function definition. On Windows, linkonce_odr is basically a no-op and
1499+
// the COMDAT we set by applying linkage gives us the desired coalescing
1500+
// behavior.
1501+
auto ForceImportThunk =
1502+
llvm::Function::Create(llvm::FunctionType::get(IGM.VoidTy, false),
1503+
llvm::GlobalValue::LinkOnceODRLinkage, buf,
1504+
&IGM.Module);
1505+
ForceImportThunk->setAttributes(IGM.constructInitialAttributes());
1506+
ApplyIRLinkage(IRLinkage::ExternalExport).to(ForceImportThunk);
1507+
if (IGM.Triple.supportsCOMDAT())
1508+
if (auto *GO = cast<llvm::GlobalObject>(ForceImportThunk))
1509+
GO->setComdat(IGM.Module.getOrInsertComdat(ForceImportThunk->getName()));
1510+
1511+
auto BB = llvm::BasicBlock::Create(IGM.getLLVMContext(), "", ForceImportThunk);
1512+
llvm::IRBuilder<> IRB(BB);
1513+
IRB.CreateRetVoid();
1514+
return ForceImportThunk;
1515+
}
1516+
}
1517+
14891518
void IRGenModule::emitAutolinkInfo() {
14901519
auto Autolink =
14911520
AutolinkKind::create(TargetInfo, Triple, IRGen.Opts.LLVMLTOKind);
@@ -1504,23 +1533,8 @@ void IRGenModule::emitAutolinkInfo() {
15041533

15051534
Autolink.writeEntries(Entries, Metadata, *this);
15061535

1507-
if (!IRGen.Opts.ForceLoadSymbolName.empty() &&
1508-
(Triple.supportsCOMDAT() || isFirstObjectFileInModule(*this))) {
1509-
llvm::SmallString<64> buf;
1510-
encodeForceLoadSymbolName(buf, IRGen.Opts.ForceLoadSymbolName);
1511-
auto ForceImportThunk =
1512-
llvm::Function::Create(llvm::FunctionType::get(VoidTy, false),
1513-
llvm::GlobalValue::ExternalLinkage, buf,
1514-
&Module);
1515-
ForceImportThunk->setAttributes(constructInitialAttributes());
1516-
ApplyIRLinkage(IRLinkage::ExternalExport).to(ForceImportThunk);
1517-
if (Triple.supportsCOMDAT())
1518-
if (auto *GO = cast<llvm::GlobalObject>(ForceImportThunk))
1519-
GO->setComdat(Module.getOrInsertComdat(ForceImportThunk->getName()));
1520-
1521-
auto BB = llvm::BasicBlock::Create(getLLVMContext(), "", ForceImportThunk);
1522-
llvm::IRBuilder<> IRB(BB);
1523-
IRB.CreateRetVoid();
1536+
if (!IRGen.Opts.ForceLoadSymbolName.empty()) {
1537+
(void) createForceImportThunk(*this);
15241538
}
15251539
}
15261540

‎lib/IRGen/Linking.cpp‎

Lines changed: 6 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -50,6 +50,12 @@ const IRLinkage IRLinkage::Internal = {
5050
llvm::GlobalValue::DefaultStorageClass,
5151
};
5252

53+
const IRLinkage IRLinkage::ExternalCommon = {
54+
llvm::GlobalValue::CommonLinkage,
55+
llvm::GlobalValue::DefaultVisibility,
56+
llvm::GlobalValue::DLLExportStorageClass,
57+
};
58+
5359
const IRLinkage IRLinkage::ExternalImport = {
5460
llvm::GlobalValue::ExternalLinkage,
5561
llvm::GlobalValue::DefaultVisibility,

‎lib/TBDGen/TBDGen.cpp‎

Lines changed: 4 additions & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -1186,9 +1186,6 @@ static bool hasLinkerDirective(Decl *D) {
11861186
}
11871187

11881188
void TBDGenVisitor::visitFile(FileUnit *file) {
1189-
if (file == SwiftModule->getFiles()[0])
1190-
addFirstFileSymbols();
1191-
11921189
SmallVector<Decl *, 16> decls;
11931190
file->getTopLevelDecls(decls);
11941191

@@ -1202,6 +1199,9 @@ void TBDGenVisitor::visitFile(FileUnit *file) {
12021199
}
12031200

12041201
void TBDGenVisitor::visit(const TBDGenDescriptor &desc) {
1202+
// Add any autolinking force_load symbols.
1203+
addFirstFileSymbols();
1204+
12051205
if (auto *singleFile = desc.getSingleFile()) {
12061206
assert(SwiftModule == singleFile->getParentModule() &&
12071207
"mismatched file and module");
@@ -1230,6 +1230,7 @@ void TBDGenVisitor::visit(const TBDGenDescriptor &desc) {
12301230
// Diagnose module name that cannot be found
12311231
ctx.Diags.diagnose(SourceLoc(), diag::unknown_swift_module_name, Name);
12321232
}
1233+
12331234
// Collect symbols in each module.
12341235
llvm::for_each(Modules, [&](ModuleDecl *M) {
12351236
for (auto *file : M->getFiles()) {

‎test/Driver/autolink-force-load-comdat.swift‎

Lines changed: 0 additions & 10 deletions
This file was deleted.

‎test/Driver/autolink-force-load-no-comdat.swift‎

Lines changed: 0 additions & 8 deletions
This file was deleted.

‎test/IRGen/autolink-force-link.swift‎

Lines changed: 5 additions & 7 deletions
Original file line numberDiff line numberDiff line change
@@ -3,27 +3,25 @@
33
// RUN: %swift -disable-legacy-type-info -target x86_64-apple-macosx10.9 -parse-stdlib -autolink-force-load -module-name TEST -module-link-name TEST -emit-ir %s %S/../Inputs/empty.swift | %FileCheck -check-prefix=CHECK-WMO %s
44

55
// CHECK-WMO: source_filename = "<swift-imported-modules>"
6-
// CHECK-WMO: define void @"_swift_FORCE_LOAD_$_TEST"()
6+
// CHECK-WMO: @"_swift_FORCE_LOAD_$_TEST"
77
// CHECK-WMO-NOT: source_filename
88

99

1010
// RUN: %swift -disable-legacy-type-info -target x86_64-apple-macosx10.9 -parse-stdlib -autolink-force-load -module-name TEST -module-link-name TEST -emit-ir -num-threads 1 %s %S/../Inputs/empty.swift | %FileCheck -check-prefix=CHECK-WMO-THREADED %s
1111

1212
// CHECK-WMO-THREADED: source_filename = "<swift-imported-modules>"
13-
// CHECK-WMO-THREADED: define void @"_swift_FORCE_LOAD_$_TEST"()
13+
// CHECK-WMO-THREADED: @"_swift_FORCE_LOAD_$_TEST"
1414
// CHECK-WMO-THREADED: source_filename = "<swift-imported-modules>"
15-
// CHECK-WMO-THREADED-NOT: _swift_FORCE_LOAD_$_TEST
16-
// CHECK-WMO-THREADED-NOT: source_filename
17-
15+
// CHECK-WMO-THREADED: @"_swift_FORCE_LOAD_$_TEST"
1816

1917
// RUN: %swift -disable-legacy-type-info -target x86_64-apple-macosx10.9 -parse-stdlib -autolink-force-load -module-name TEST -module-link-name TEST -emit-ir -primary-file %s %S/../Inputs/empty.swift | %FileCheck -check-prefix=CHECK-SINGLE-FILE-FIRST %s
2018
// RUN: %swift -disable-legacy-type-info -target x86_64-apple-macosx10.9 -parse-stdlib -autolink-force-load -module-name TEST -module-link-name TEST -emit-ir %S/../Inputs/empty.swift -primary-file %s | %FileCheck -check-prefix=CHECK-SINGLE-FILE-SECOND %s
2119

2220
// CHECK-SINGLE-FILE-FIRST: source_filename = "<swift-imported-modules>"
23-
// CHECK-SINGLE-FILE-FIRST: define void @"_swift_FORCE_LOAD_$_TEST"()
21+
// CHECK-SINGLE-FILE-FIRST: @"_swift_FORCE_LOAD_$_TEST"
2422
// CHECK-SINGLE-FILE-FIRST-NOT: source_filename
2523

2624
// CHECK-SINGLE-FILE-SECOND: source_filename = "<swift-imported-modules>"
27-
// CHECK-SINGLE-FILE-SECOND-NOT: _swift_FORCE_LOAD_$_TEST
25+
// CHECK-SINGLE-FILE-SECOND: @"_swift_FORCE_LOAD_$_TEST"
2826
// CHECK-SINGLE-FILE-SECOND-NOT: source_filename
2927

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