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-rw-r--r--lib/LTO/ThinLTOCodeGenerator.cpp198
1 files changed, 76 insertions, 122 deletions
diff --git a/lib/LTO/ThinLTOCodeGenerator.cpp b/lib/LTO/ThinLTOCodeGenerator.cpp
index 642e538ecf92..d9ec68fe3eb5 100644
--- a/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -29,9 +29,11 @@
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Mangler.h"
+#include "llvm/IR/PassTimingInfo.h"
#include "llvm/IR/Verifier.h"
#include "llvm/IRReader/IRReader.h"
#include "llvm/LTO/LTO.h"
+#include "llvm/LTO/SummaryBasedOptimizations.h"
#include "llvm/MC/SubtargetFeature.h"
#include "llvm/Object/IRObjectFile.h"
#include "llvm/Support/CachePruning.h"
@@ -297,8 +299,7 @@ public:
const FunctionImporter::ImportMapTy &ImportList,
const FunctionImporter::ExportSetTy &ExportList,
const std::map<GlobalValue::GUID, GlobalValue::LinkageTypes> &ResolvedODR,
- const GVSummaryMapTy &DefinedFunctions,
- const DenseSet<GlobalValue::GUID> &PreservedSymbols, unsigned OptLevel,
+ const GVSummaryMapTy &DefinedGVSummaries, unsigned OptLevel,
bool Freestanding, const TargetMachineBuilder &TMBuilder) {
if (CachePath.empty())
return;
@@ -307,87 +308,26 @@ public:
// The module does not have an entry, it can't have a hash at all
return;
- // Compute the unique hash for this entry
- // This is based on the current compiler version, the module itself, the
- // export list, the hash for every single module in the import list, the
- // list of ResolvedODR for the module, and the list of preserved symbols.
-
- // Include the hash for the current module
- auto ModHash = Index.getModuleHash(ModuleID);
-
- if (all_of(ModHash, [](uint32_t V) { return V == 0; }))
+ if (all_of(Index.getModuleHash(ModuleID),
+ [](uint32_t V) { return V == 0; }))
// No hash entry, no caching!
return;
- SHA1 Hasher;
-
- // Include the parts of the LTO configuration that affect code generation.
- auto AddString = [&](StringRef Str) {
- Hasher.update(Str);
- Hasher.update(ArrayRef<uint8_t>{0});
- };
- auto AddUnsigned = [&](unsigned I) {
- uint8_t Data[4];
- Data[0] = I;
- Data[1] = I >> 8;
- Data[2] = I >> 16;
- Data[3] = I >> 24;
- Hasher.update(ArrayRef<uint8_t>{Data, 4});
- };
-
- // Start with the compiler revision
- Hasher.update(LLVM_VERSION_STRING);
-#ifdef LLVM_REVISION
- Hasher.update(LLVM_REVISION);
-#endif
-
- // Hash the optimization level and the target machine settings.
- AddString(TMBuilder.MCpu);
- // FIXME: Hash more of Options. For now all clients initialize Options from
- // command-line flags (which is unsupported in production), but may set
- // RelaxELFRelocations. The clang driver can also pass FunctionSections,
- // DataSections and DebuggerTuning via command line flags.
- AddUnsigned(TMBuilder.Options.RelaxELFRelocations);
- AddUnsigned(TMBuilder.Options.FunctionSections);
- AddUnsigned(TMBuilder.Options.DataSections);
- AddUnsigned((unsigned)TMBuilder.Options.DebuggerTuning);
- AddString(TMBuilder.MAttr);
- if (TMBuilder.RelocModel)
- AddUnsigned(*TMBuilder.RelocModel);
- AddUnsigned(TMBuilder.CGOptLevel);
- AddUnsigned(OptLevel);
- AddUnsigned(Freestanding);
-
- Hasher.update(ArrayRef<uint8_t>((uint8_t *)&ModHash[0], sizeof(ModHash)));
- for (auto F : ExportList)
- // The export list can impact the internalization, be conservative here
- Hasher.update(ArrayRef<uint8_t>((uint8_t *)&F, sizeof(F)));
-
- // Include the hash for every module we import functions from
- for (auto &Entry : ImportList) {
- auto ModHash = Index.getModuleHash(Entry.first());
- Hasher.update(ArrayRef<uint8_t>((uint8_t *)&ModHash[0], sizeof(ModHash)));
- }
-
- // Include the hash for the resolved ODR.
- for (auto &Entry : ResolvedODR) {
- Hasher.update(ArrayRef<uint8_t>((const uint8_t *)&Entry.first,
- sizeof(GlobalValue::GUID)));
- Hasher.update(ArrayRef<uint8_t>((const uint8_t *)&Entry.second,
- sizeof(GlobalValue::LinkageTypes)));
- }
-
- // Include the hash for the preserved symbols.
- for (auto &Entry : PreservedSymbols) {
- if (DefinedFunctions.count(Entry))
- Hasher.update(
- ArrayRef<uint8_t>((const uint8_t *)&Entry, sizeof(GlobalValue::GUID)));
- }
+ llvm::lto::Config Conf;
+ Conf.OptLevel = OptLevel;
+ Conf.Options = TMBuilder.Options;
+ Conf.CPU = TMBuilder.MCpu;
+ Conf.MAttrs.push_back(TMBuilder.MAttr);
+ Conf.RelocModel = TMBuilder.RelocModel;
+ Conf.CGOptLevel = TMBuilder.CGOptLevel;
+ Conf.Freestanding = Freestanding;
+ SmallString<40> Key;
+ computeLTOCacheKey(Key, Conf, Index, ModuleID, ImportList, ExportList,
+ ResolvedODR, DefinedGVSummaries);
// This choice of file name allows the cache to be pruned (see pruneCache()
// in include/llvm/Support/CachePruning.h).
- sys::path::append(EntryPath, CachePath,
- "llvmcache-" + toHex(Hasher.result()));
+ sys::path::append(EntryPath, CachePath, "llvmcache-" + Key);
}
// Access the path to this entry in the cache.
@@ -456,8 +396,8 @@ ProcessThinLTOModule(Module &TheModule, ModuleSummaryIndex &Index,
if (!SingleModule) {
promoteModule(TheModule, Index);
- // Apply summary-based LinkOnce/Weak resolution decisions.
- thinLTOResolveWeakForLinkerModule(TheModule, DefinedGlobals);
+ // Apply summary-based prevailing-symbol resolution decisions.
+ thinLTOResolvePrevailingInModule(TheModule, DefinedGlobals);
// Save temps: after promotion.
saveTempBitcode(TheModule, SaveTempsDir, count, ".1.promoted.bc");
@@ -499,12 +439,12 @@ ProcessThinLTOModule(Module &TheModule, ModuleSummaryIndex &Index,
return codegenModule(TheModule, TM);
}
-/// Resolve LinkOnce/Weak symbols. Record resolutions in the \p ResolvedODR map
+/// Resolve prevailing symbols. Record resolutions in the \p ResolvedODR map
/// for caching, and in the \p Index for application during the ThinLTO
/// backends. This is needed for correctness for exported symbols (ensure
/// at least one copy kept) and a compile-time optimization (to drop duplicate
/// copies when possible).
-static void resolveWeakForLinkerInIndex(
+static void resolvePrevailingInIndex(
ModuleSummaryIndex &Index,
StringMap<std::map<GlobalValue::GUID, GlobalValue::LinkageTypes>>
&ResolvedODR) {
@@ -526,7 +466,7 @@ static void resolveWeakForLinkerInIndex(
ResolvedODR[ModuleIdentifier][GUID] = NewLinkage;
};
- thinLTOResolveWeakForLinkerInIndex(Index, isPrevailing, recordNewLinkage);
+ thinLTOResolvePrevailingInIndex(Index, isPrevailing, recordNewLinkage);
}
// Initialize the TargetMachine builder for a given Triple
@@ -645,7 +585,8 @@ static void computeDeadSymbolsInIndex(
auto isPrevailing = [&](GlobalValue::GUID G) {
return PrevailingType::Unknown;
};
- computeDeadSymbols(Index, GUIDPreservedSymbols, isPrevailing);
+ computeDeadSymbolsWithConstProp(Index, GUIDPreservedSymbols, isPrevailing,
+ /* ImportEnabled = */ true);
}
/**
@@ -674,11 +615,11 @@ void ThinLTOCodeGenerator::promote(Module &TheModule,
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
- // Resolve LinkOnce/Weak symbols.
+ // Resolve prevailing symbols
StringMap<std::map<GlobalValue::GUID, GlobalValue::LinkageTypes>> ResolvedODR;
- resolveWeakForLinkerInIndex(Index, ResolvedODR);
+ resolvePrevailingInIndex(Index, ResolvedODR);
- thinLTOResolveWeakForLinkerModule(
+ thinLTOResolvePrevailingInModule(
TheModule, ModuleToDefinedGVSummaries[ModuleIdentifier]);
// Promote the exported values in the index, so that they are promoted
@@ -721,37 +662,52 @@ void ThinLTOCodeGenerator::crossModuleImport(Module &TheModule,
* Compute the list of summaries needed for importing into module.
*/
void ThinLTOCodeGenerator::gatherImportedSummariesForModule(
- StringRef ModulePath, ModuleSummaryIndex &Index,
+ Module &TheModule, ModuleSummaryIndex &Index,
std::map<std::string, GVSummaryMapTy> &ModuleToSummariesForIndex) {
auto ModuleCount = Index.modulePaths().size();
+ auto ModuleIdentifier = TheModule.getModuleIdentifier();
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
+ // Convert the preserved symbols set from string to GUID
+ auto GUIDPreservedSymbols = computeGUIDPreservedSymbols(
+ PreservedSymbols, Triple(TheModule.getTargetTriple()));
+
+ // Compute "dead" symbols, we don't want to import/export these!
+ computeDeadSymbolsInIndex(Index, GUIDPreservedSymbols);
+
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
ComputeCrossModuleImport(Index, ModuleToDefinedGVSummaries, ImportLists,
ExportLists);
- llvm::gatherImportedSummariesForModule(ModulePath, ModuleToDefinedGVSummaries,
- ImportLists[ModulePath],
- ModuleToSummariesForIndex);
+ llvm::gatherImportedSummariesForModule(
+ ModuleIdentifier, ModuleToDefinedGVSummaries,
+ ImportLists[ModuleIdentifier], ModuleToSummariesForIndex);
}
/**
* Emit the list of files needed for importing into module.
*/
-void ThinLTOCodeGenerator::emitImports(StringRef ModulePath,
- StringRef OutputName,
+void ThinLTOCodeGenerator::emitImports(Module &TheModule, StringRef OutputName,
ModuleSummaryIndex &Index) {
auto ModuleCount = Index.modulePaths().size();
+ auto ModuleIdentifier = TheModule.getModuleIdentifier();
// Collect for each module the list of function it defines (GUID -> Summary).
StringMap<GVSummaryMapTy> ModuleToDefinedGVSummaries(ModuleCount);
Index.collectDefinedGVSummariesPerModule(ModuleToDefinedGVSummaries);
+ // Convert the preserved symbols set from string to GUID
+ auto GUIDPreservedSymbols = computeGUIDPreservedSymbols(
+ PreservedSymbols, Triple(TheModule.getTargetTriple()));
+
+ // Compute "dead" symbols, we don't want to import/export these!
+ computeDeadSymbolsInIndex(Index, GUIDPreservedSymbols);
+
// Generate import/export list
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
StringMap<FunctionImporter::ExportSetTy> ExportLists(ModuleCount);
@@ -759,13 +715,13 @@ void ThinLTOCodeGenerator::emitImports(StringRef ModulePath,
ExportLists);
std::map<std::string, GVSummaryMapTy> ModuleToSummariesForIndex;
- llvm::gatherImportedSummariesForModule(ModulePath, ModuleToDefinedGVSummaries,
- ImportLists[ModulePath],
- ModuleToSummariesForIndex);
+ llvm::gatherImportedSummariesForModule(
+ ModuleIdentifier, ModuleToDefinedGVSummaries,
+ ImportLists[ModuleIdentifier], ModuleToSummariesForIndex);
std::error_code EC;
- if ((EC =
- EmitImportsFiles(ModulePath, OutputName, ModuleToSummariesForIndex)))
+ if ((EC = EmitImportsFiles(ModuleIdentifier, OutputName,
+ ModuleToSummariesForIndex)))
report_fatal_error(Twine("Failed to open ") + OutputName +
" to save imports lists\n");
}
@@ -818,14 +774,6 @@ void ThinLTOCodeGenerator::optimize(Module &TheModule) {
optimizeModule(TheModule, *TMBuilder.create(), OptLevel, Freestanding);
}
-/**
- * Perform ThinLTO CodeGen.
- */
-std::unique_ptr<MemoryBuffer> ThinLTOCodeGenerator::codegen(Module &TheModule) {
- initTMBuilder(TMBuilder, Triple(TheModule.getTargetTriple()));
- return codegenModule(TheModule, *TMBuilder.create());
-}
-
/// Write out the generated object file, either from CacheEntryPath or from
/// OutputBuffer, preferring hard-link when possible.
/// Returns the path to the generated file in SavedObjectsDirectoryPath.
@@ -893,7 +841,7 @@ void ThinLTOCodeGenerator::run() {
/*IsImporting*/ false);
// CodeGen
- auto OutputBuffer = codegen(*TheModule);
+ auto OutputBuffer = codegenModule(*TheModule, *TMBuilder.create());
if (SavedObjectsDirectoryPath.empty())
ProducedBinaries[count] = std::move(OutputBuffer);
else
@@ -936,6 +884,9 @@ void ThinLTOCodeGenerator::run() {
// Compute "dead" symbols, we don't want to import/export these!
computeDeadSymbolsInIndex(*Index, GUIDPreservedSymbols);
+ // Synthesize entry counts for functions in the combined index.
+ computeSyntheticCounts(*Index);
+
// Collect the import/export lists for all modules from the call-graph in the
// combined index.
StringMap<FunctionImporter::ImportMapTy> ImportLists(ModuleCount);
@@ -949,20 +900,24 @@ void ThinLTOCodeGenerator::run() {
// on the index, and nuke this map.
StringMap<std::map<GlobalValue::GUID, GlobalValue::LinkageTypes>> ResolvedODR;
- // Resolve LinkOnce/Weak symbols, this has to be computed early because it
+ // Resolve prevailing symbols, this has to be computed early because it
// impacts the caching.
- resolveWeakForLinkerInIndex(*Index, ResolvedODR);
+ resolvePrevailingInIndex(*Index, ResolvedODR);
// Use global summary-based analysis to identify symbols that can be
// internalized (because they aren't exported or preserved as per callback).
// Changes are made in the index, consumed in the ThinLTO backends.
internalizeAndPromoteInIndex(ExportLists, GUIDPreservedSymbols, *Index);
- // Make sure that every module has an entry in the ExportLists and
- // ResolvedODR maps to enable threaded access to these maps below.
- for (auto &DefinedGVSummaries : ModuleToDefinedGVSummaries) {
- ExportLists[DefinedGVSummaries.first()];
- ResolvedODR[DefinedGVSummaries.first()];
+ // Make sure that every module has an entry in the ExportLists, ImportList,
+ // GVSummary and ResolvedODR maps to enable threaded access to these maps
+ // below.
+ for (auto &Module : Modules) {
+ auto ModuleIdentifier = Module.getBufferIdentifier();
+ ExportLists[ModuleIdentifier];
+ ImportLists[ModuleIdentifier];
+ ResolvedODR[ModuleIdentifier];
+ ModuleToDefinedGVSummaries[ModuleIdentifier];
}
// Compute the ordering we will process the inputs: the rough heuristic here
@@ -971,12 +926,11 @@ void ThinLTOCodeGenerator::run() {
std::vector<int> ModulesOrdering;
ModulesOrdering.resize(Modules.size());
std::iota(ModulesOrdering.begin(), ModulesOrdering.end(), 0);
- llvm::sort(ModulesOrdering.begin(), ModulesOrdering.end(),
- [&](int LeftIndex, int RightIndex) {
- auto LSize = Modules[LeftIndex].getBuffer().size();
- auto RSize = Modules[RightIndex].getBuffer().size();
- return LSize > RSize;
- });
+ llvm::sort(ModulesOrdering, [&](int LeftIndex, int RightIndex) {
+ auto LSize = Modules[LeftIndex].getBuffer().size();
+ auto RSize = Modules[RightIndex].getBuffer().size();
+ return LSize > RSize;
+ });
// Parallel optimizer + codegen
{
@@ -987,14 +941,14 @@ void ThinLTOCodeGenerator::run() {
auto ModuleIdentifier = ModuleBuffer.getBufferIdentifier();
auto &ExportList = ExportLists[ModuleIdentifier];
- auto &DefinedFunctions = ModuleToDefinedGVSummaries[ModuleIdentifier];
+ auto &DefinedGVSummaries = ModuleToDefinedGVSummaries[ModuleIdentifier];
// The module may be cached, this helps handling it.
ModuleCacheEntry CacheEntry(CacheOptions.Path, *Index, ModuleIdentifier,
ImportLists[ModuleIdentifier], ExportList,
ResolvedODR[ModuleIdentifier],
- DefinedFunctions, GUIDPreservedSymbols,
- OptLevel, Freestanding, TMBuilder);
+ DefinedGVSummaries, OptLevel, Freestanding,
+ TMBuilder);
auto CacheEntryPath = CacheEntry.getEntryPath();
{
generated by cgit v1.3 (git 2.53.0) at 2026-07-29 06:49:06 +0000