Revert "[ThinLTO] Add an auto-hide feature"
This reverts commit r293918, one lld test does not pass.
llvm-svn: 293961
diff --git a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
index 0227eab..f5ba637 100644
--- a/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
+++ b/llvm/lib/Analysis/ModuleSummaryAnalysis.cpp
@@ -190,8 +190,7 @@
// FIXME: refactor this to use the same code that inliner is using.
F.isVarArg();
GlobalValueSummary::GVFlags Flags(F.getLinkage(), NotEligibleForImport,
- /* LiveRoot = */ false,
- /* AutoHide */ false);
+ /* LiveRoot = */ false);
auto FuncSummary = llvm::make_unique<FunctionSummary>(
Flags, NumInsts, RefEdges.takeVector(), CallGraphEdges.takeVector(),
TypeTests.takeVector());
@@ -208,8 +207,7 @@
findRefEdges(&V, RefEdges, Visited);
bool NonRenamableLocal = isNonRenamableLocal(V);
GlobalValueSummary::GVFlags Flags(V.getLinkage(), NonRenamableLocal,
- /* LiveRoot = */ false,
- /* AutoHide */ false);
+ /* LiveRoot = */ false);
auto GVarSummary =
llvm::make_unique<GlobalVarSummary>(Flags, RefEdges.takeVector());
if (NonRenamableLocal)
@@ -222,8 +220,7 @@
DenseSet<GlobalValue::GUID> &CantBePromoted) {
bool NonRenamableLocal = isNonRenamableLocal(A);
GlobalValueSummary::GVFlags Flags(A.getLinkage(), NonRenamableLocal,
- /* LiveRoot = */ false,
- /* AutoHide */ false);
+ /* LiveRoot = */ false);
auto AS = llvm::make_unique<AliasSummary>(Flags, ArrayRef<ValueInfo>{});
auto *Aliasee = A.getBaseObject();
auto *AliaseeSummary = Index.getGlobalValueSummary(*Aliasee);
@@ -342,8 +339,7 @@
assert(GV->isDeclaration() && "Def in module asm already has definition");
GlobalValueSummary::GVFlags GVFlags(GlobalValue::InternalLinkage,
/* NotEligibleToImport */ true,
- /* LiveRoot */ true,
- /* AutoHide */ false);
+ /* LiveRoot */ true);
CantBePromoted.insert(GlobalValue::getGUID(Name));
// Create the appropriate summary type.
if (isa<Function>(GV)) {
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index c9d2ad5..a46e49c 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -800,14 +800,13 @@
// like getDecodedLinkage() above. Any future change to the linkage enum and
// to getDecodedLinkage() will need to be taken into account here as above.
auto Linkage = GlobalValue::LinkageTypes(RawFlags & 0xF); // 4 bits
- bool NotEligibleToImport = ((RawFlags >> 4) & 0x1) || Version < 3;
+ RawFlags = RawFlags >> 4;
+ bool NotEligibleToImport = (RawFlags & 0x1) || Version < 3;
// The LiveRoot flag wasn't introduced until version 3. For dead stripping
// to work correctly on earlier versions, we must conservatively treat all
// values as live.
- bool LiveRoot = ((RawFlags >> 5) & 0x1) || Version < 3;
- bool AutoHide = (RawFlags >> 6) & 0x1;
- return GlobalValueSummary::GVFlags(Linkage, NotEligibleToImport, LiveRoot,
- AutoHide);
+ bool LiveRoot = (RawFlags & 0x2) || Version < 3;
+ return GlobalValueSummary::GVFlags(Linkage, NotEligibleToImport, LiveRoot);
}
static GlobalValue::VisibilityTypes getDecodedVisibility(unsigned Val) {
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index bdb57f5..4eac89c 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -971,13 +971,13 @@
static uint64_t getEncodedGVSummaryFlags(GlobalValueSummary::GVFlags Flags) {
uint64_t RawFlags = 0;
+ RawFlags |= Flags.NotEligibleToImport; // bool
+ RawFlags |= (Flags.LiveRoot << 1);
// Linkage don't need to be remapped at that time for the summary. Any future
// change to the getEncodedLinkage() function will need to be taken into
// account here as well.
- RawFlags |= Flags.Linkage; // 4 bits linkage
- RawFlags |= (Flags.NotEligibleToImport << 4); // bool
- RawFlags |= (Flags.LiveRoot << 5); // bool
- RawFlags |= (Flags.AutoHide << 6); // bool
+ RawFlags = (RawFlags << 4) | Flags.Linkage; // 4 bits
+
return RawFlags;
}
diff --git a/llvm/lib/LTO/LTO.cpp b/llvm/lib/LTO/LTO.cpp
index db02531..bf30fec 100644
--- a/llvm/lib/LTO/LTO.cpp
+++ b/llvm/lib/LTO/LTO.cpp
@@ -203,14 +203,11 @@
static void thinLTOInternalizeAndPromoteGUID(
GlobalValueSummaryList &GVSummaryList, GlobalValue::GUID GUID,
- function_ref<SummaryResolution(StringRef, GlobalValue::GUID)> isExported) {
+ function_ref<bool(StringRef, GlobalValue::GUID)> isExported) {
for (auto &S : GVSummaryList) {
- auto ExportResolution = isExported(S->modulePath(), GUID);
- if (ExportResolution != Internal) {
+ if (isExported(S->modulePath(), GUID)) {
if (GlobalValue::isLocalLinkage(S->linkage()))
S->setLinkage(GlobalValue::ExternalLinkage);
- if (ExportResolution == Hidden)
- S->setAutoHide();
} else if (!GlobalValue::isLocalLinkage(S->linkage()))
S->setLinkage(GlobalValue::InternalLinkage);
}
@@ -220,7 +217,7 @@
// as external and non-exported values as internal.
void llvm::thinLTOInternalizeAndPromoteInIndex(
ModuleSummaryIndex &Index,
- function_ref<SummaryResolution(StringRef, GlobalValue::GUID)> isExported) {
+ function_ref<bool(StringRef, GlobalValue::GUID)> isExported) {
for (auto &I : Index)
thinLTOInternalizeAndPromoteGUID(I.second, I.first, isExported);
}
@@ -954,20 +951,11 @@
const GlobalValueSummary *S) {
return ThinLTO.PrevailingModuleForGUID[GUID] == S->modulePath();
};
- auto isExported = [&](StringRef ModuleIdentifier,
- GlobalValue::GUID GUID) -> SummaryResolution {
+ auto isExported = [&](StringRef ModuleIdentifier, GlobalValue::GUID GUID) {
const auto &ExportList = ExportLists.find(ModuleIdentifier);
- if ((ExportList != ExportLists.end() && ExportList->second.count(GUID)) ||
- ExportedGUIDs.count(GUID)) {
- // We could do better by hiding when a symbol is in
- // GUIDPreservedSymbols because it is only referenced from regular LTO
- // or from native files and not outside the final binary, but that's
- // something the native linker could do as gwell.
- if (GUIDPreservedSymbols.count(GUID))
- return Exported;
- return Hidden;
- }
- return Internal;
+ return (ExportList != ExportLists.end() &&
+ ExportList->second.count(GUID)) ||
+ ExportedGUIDs.count(GUID);
};
thinLTOInternalizeAndPromoteInIndex(ThinLTO.CombinedIndex, isExported);
diff --git a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
index b62db61..104fb19 100644
--- a/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/llvm/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -234,16 +234,16 @@
// Convert the PreservedSymbols map from "Name" based to "GUID" based.
static DenseSet<GlobalValue::GUID>
-convertSymbolNamesToGUID(const StringSet<> &NamedSymbols,
- const Triple &TheTriple) {
- DenseSet<GlobalValue::GUID> GUIDSymbols(NamedSymbols.size());
- for (auto &Entry : NamedSymbols) {
+computeGUIDPreservedSymbols(const StringSet<> &PreservedSymbols,
+ const Triple &TheTriple) {
+ DenseSet<GlobalValue::GUID> GUIDPreservedSymbols(PreservedSymbols.size());
+ for (auto &Entry : PreservedSymbols) {
StringRef Name = Entry.first();
if (TheTriple.isOSBinFormatMachO() && Name.size() > 0 && Name[0] == '_')
Name = Name.drop_front();
- GUIDSymbols.insert(GlobalValue::getGUID(Name));
+ GUIDPreservedSymbols.insert(GlobalValue::getGUID(Name));
}
- return GUIDSymbols;
+ return GUIDPreservedSymbols;
}
std::unique_ptr<MemoryBuffer> codegenModule(Module &TheModule,
@@ -554,7 +554,10 @@
}
void ThinLTOCodeGenerator::crossReferenceSymbol(StringRef Name) {
- CrossReferencedSymbols.insert(Name);
+ // FIXME: At the moment, we don't take advantage of this extra information,
+ // we're conservatively considering cross-references as preserved.
+ // CrossReferencedSymbols.insert(Name);
+ PreservedSymbols.insert(Name);
}
// TargetMachine factory
@@ -617,7 +620,7 @@
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Convert the preserved symbols set from string to GUID
- auto GUIDPreservedSymbols = convertSymbolNamesToGUID(
+ auto GUIDPreservedSymbols = computeGUIDPreservedSymbols(
PreservedSymbols, Triple(TheModule.getTargetTriple()));
// Compute "dead" symbols, we don't want to import/export these!
@@ -638,13 +641,11 @@
// Promote the exported values in the index, so that they are promoted
// in the module.
- auto isExported = [&](StringRef ModuleIdentifier,
- GlobalValue::GUID GUID) -> SummaryResolution {
+ auto isExported = [&](StringRef ModuleIdentifier, GlobalValue::GUID GUID) {
const auto &ExportList = ExportLists.find(ModuleIdentifier);
- if ((ExportList != ExportLists.end() && ExportList->second.count(GUID)) ||
- GUIDPreservedSymbols.count(GUID))
- return Exported;
- return Internal;
+ return (ExportList != ExportLists.end() &&
+ ExportList->second.count(GUID)) ||
+ GUIDPreservedSymbols.count(GUID);
};
thinLTOInternalizeAndPromoteInIndex(Index, isExported);
@@ -664,7 +665,7 @@
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
// Convert the preserved symbols set from string to GUID
- auto GUIDPreservedSymbols = convertSymbolNamesToGUID(
+ auto GUIDPreservedSymbols = computeGUIDPreservedSymbols(
PreservedSymbols, Triple(TheModule.getTargetTriple()));
// Compute "dead" symbols, we don't want to import/export these!
@@ -738,7 +739,7 @@
// Convert the preserved symbols set from string to GUID
auto GUIDPreservedSymbols =
- convertSymbolNamesToGUID(PreservedSymbols, TMBuilder.TheTriple);
+ computeGUIDPreservedSymbols(PreservedSymbols, TMBuilder.TheTriple);
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
@@ -760,13 +761,11 @@
return;
// Internalization
- auto isExported = [&](StringRef ModuleIdentifier,
- GlobalValue::GUID GUID) -> SummaryResolution {
+ auto isExported = [&](StringRef ModuleIdentifier, GlobalValue::GUID GUID) {
const auto &ExportList = ExportLists.find(ModuleIdentifier);
- if ((ExportList != ExportLists.end() && ExportList->second.count(GUID)) ||
- GUIDPreservedSymbols.count(GUID))
- return Exported;
- return Internal;
+ return (ExportList != ExportLists.end() &&
+ ExportList->second.count(GUID)) ||
+ GUIDPreservedSymbols.count(GUID);
};
thinLTOInternalizeAndPromoteInIndex(Index, isExported);
thinLTOInternalizeModule(TheModule,
@@ -895,9 +894,7 @@
// Convert the preserved symbols set from string to GUID, this is needed for
// computing the caching hash and the internalization.
auto GUIDPreservedSymbols =
- convertSymbolNamesToGUID(PreservedSymbols, TMBuilder.TheTriple);
- auto GUIDCrossRefSymbols =
- convertSymbolNamesToGUID(CrossReferencedSymbols, TMBuilder.TheTriple);
+ computeGUIDPreservedSymbols(PreservedSymbols, TMBuilder.TheTriple);
// Compute "dead" symbols, we don't want to import/export these!
auto DeadSymbols = computeDeadSymbols(*Index, GUIDPreservedSymbols);
@@ -919,16 +916,11 @@
// impacts the caching.
resolveWeakForLinkerInIndex(*Index, ResolvedODR);
- auto isExported = [&](StringRef ModuleIdentifier,
- GlobalValue::GUID GUID) -> SummaryResolution {
- if (GUIDPreservedSymbols.count(GUID))
- return Exported;
- if (GUIDCrossRefSymbols.count(GUID))
- return Hidden;
+ auto isExported = [&](StringRef ModuleIdentifier, GlobalValue::GUID GUID) {
const auto &ExportList = ExportLists.find(ModuleIdentifier);
- if (ExportList != ExportLists.end() && ExportList->second.count(GUID))
- return Hidden;
- return Internal;
+ return (ExportList != ExportLists.end() &&
+ ExportList->second.count(GUID)) ||
+ GUIDPreservedSymbols.count(GUID);
};
// Use global summary-based analysis to identify symbols that can be
diff --git a/llvm/lib/Transforms/IPO/FunctionImport.cpp b/llvm/lib/Transforms/IPO/FunctionImport.cpp
index 2966be2..5fa9986 100644
--- a/llvm/lib/Transforms/IPO/FunctionImport.cpp
+++ b/llvm/lib/Transforms/IPO/FunctionImport.cpp
@@ -644,13 +644,6 @@
return !GlobalValue::isLocalLinkage(Linkage);
};
- // Try to auto-hide the symbols.
- for (auto &GO : TheModule.global_objects()) {
- const auto &GS = DefinedGlobals.find(GO.getGUID());
- if (GS != DefinedGlobals.end() && GS->second->flags().AutoHide)
- GO.setVisibility(GlobalValue::HiddenVisibility);
- }
-
// FIXME: See if we can just internalize directly here via linkage changes
// based on the index, rather than invoking internalizeModule.
llvm::internalizeModule(TheModule, MustPreserveGV);