diff options
author | Peter Collingbourne <peter@pcc.me.uk> | 2017-06-15 17:26:13 +0000 |
---|---|---|
committer | Peter Collingbourne <peter@pcc.me.uk> | 2017-06-15 17:26:13 +0000 |
commit | 95d9f1b4f9b749a1843b4e9bd90413248112091b (patch) | |
tree | caa7e50b45c57db227ef9bde54be9b44bfefca2b /lib/Bitcode | |
parent | 52ffcca2b54a79b810654d1a70d51161570a2f98 (diff) |
Apply summary-based dead stripping to regular LTO modules with summaries.
If a regular LTO module has a summary index, then instead of linking
it into the combined regular LTO module right away, add it to the
combined summary index and associate it with a special module that
represents the combined regular LTO module.
Any such modules are linked during LTO::run(), at which time we use
the results of summary-based dead stripping to control whether to
link prevailing symbols.
Differential Revision: https://reviews.llvm.org/D33922
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305482 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Bitcode')
-rw-r--r-- | lib/Bitcode/Reader/BitcodeReader.cpp | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp index d87f5409170..e732daaea2e 100644 --- a/lib/Bitcode/Reader/BitcodeReader.cpp +++ b/lib/Bitcode/Reader/BitcodeReader.cpp @@ -733,7 +733,7 @@ private: std::vector<FunctionSummary::EdgeTy> makeCallList(ArrayRef<uint64_t> Record, bool IsOldProfileFormat, bool HasProfile); - Error parseEntireSummary(); + Error parseEntireSummary(unsigned ID); Error parseModuleStringTable(); std::pair<ValueInfo, GlobalValue::GUID> @@ -4854,6 +4854,7 @@ Error ModuleSummaryIndexBitcodeReader::parseModule() { return error("Invalid record"); break; case bitc::GLOBALVAL_SUMMARY_BLOCK_ID: + case bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID: assert(!SeenValueSymbolTable && "Already read VST when parsing summary block?"); // We might not have a VST if there were no values in the @@ -4866,7 +4867,7 @@ Error ModuleSummaryIndexBitcodeReader::parseModule() { SeenValueSymbolTable = true; } SeenGlobalValSummary = true; - if (Error Err = parseEntireSummary()) + if (Error Err = parseEntireSummary(Entry.ID)) return Err; break; case bitc::MODULE_STRTAB_BLOCK_ID: @@ -4974,8 +4975,8 @@ std::vector<FunctionSummary::EdgeTy> ModuleSummaryIndexBitcodeReader::makeCallLi // Eagerly parse the entire summary block. This populates the GlobalValueSummary // objects in the index. -Error ModuleSummaryIndexBitcodeReader::parseEntireSummary() { - if (Stream.EnterSubBlock(bitc::GLOBALVAL_SUMMARY_BLOCK_ID)) +Error ModuleSummaryIndexBitcodeReader::parseEntireSummary(unsigned ID) { + if (Stream.EnterSubBlock(ID)) return error("Invalid record"); SmallVector<uint64_t, 64> Record; @@ -5517,13 +5518,16 @@ BitcodeModule::getLazyModule(LLVMContext &Context, bool ShouldLazyLoadMetadata, } // Parse the specified bitcode buffer and merge the index into CombinedIndex. +// We don't use ModuleIdentifier here because the client may need to control the +// module path used in the combined summary (e.g. when reading summaries for +// regular LTO modules). Error BitcodeModule::readSummary(ModuleSummaryIndex &CombinedIndex, - unsigned ModuleId) { + StringRef ModulePath, uint64_t ModuleId) { BitstreamCursor Stream(Buffer); Stream.JumpToBit(ModuleBit); ModuleSummaryIndexBitcodeReader R(std::move(Stream), Strtab, CombinedIndex, - ModuleIdentifier, ModuleId); + ModulePath, ModuleId); return R.parseModule(); } @@ -5543,7 +5547,7 @@ Expected<std::unique_ptr<ModuleSummaryIndex>> BitcodeModule::getSummary() { } // Check if the given bitcode buffer contains a global value summary block. -Expected<bool> BitcodeModule::hasSummary() { +Expected<BitcodeLTOInfo> BitcodeModule::getLTOInfo() { BitstreamCursor Stream(Buffer); Stream.JumpToBit(ModuleBit); @@ -5557,11 +5561,14 @@ Expected<bool> BitcodeModule::hasSummary() { case BitstreamEntry::Error: return error("Malformed block"); case BitstreamEntry::EndBlock: - return false; + return BitcodeLTOInfo{/*IsThinLTO=*/false, /*HasSummary=*/false}; case BitstreamEntry::SubBlock: if (Entry.ID == bitc::GLOBALVAL_SUMMARY_BLOCK_ID) - return true; + return BitcodeLTOInfo{/*IsThinLTO=*/true, /*HasSummary=*/true}; + + if (Entry.ID == bitc::FULL_LTO_GLOBALVAL_SUMMARY_BLOCK_ID) + return BitcodeLTOInfo{/*IsThinLTO=*/false, /*HasSummary=*/true}; // Ignore other sub-blocks. if (Stream.SkipBlock()) @@ -5648,12 +5655,12 @@ Expected<std::string> llvm::getBitcodeProducerString(MemoryBufferRef Buffer) { Error llvm::readModuleSummaryIndex(MemoryBufferRef Buffer, ModuleSummaryIndex &CombinedIndex, - unsigned ModuleId) { + uint64_t ModuleId) { Expected<BitcodeModule> BM = getSingleModule(Buffer); if (!BM) return BM.takeError(); - return BM->readSummary(CombinedIndex, ModuleId); + return BM->readSummary(CombinedIndex, BM->getModuleIdentifier(), ModuleId); } Expected<std::unique_ptr<ModuleSummaryIndex>> @@ -5665,12 +5672,12 @@ llvm::getModuleSummaryIndex(MemoryBufferRef Buffer) { return BM->getSummary(); } -Expected<bool> llvm::hasGlobalValueSummary(MemoryBufferRef Buffer) { +Expected<BitcodeLTOInfo> llvm::getBitcodeLTOInfo(MemoryBufferRef Buffer) { Expected<BitcodeModule> BM = getSingleModule(Buffer); if (!BM) return BM.takeError(); - return BM->hasSummary(); + return BM->getLTOInfo(); } Expected<std::unique_ptr<ModuleSummaryIndex>> |