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2017-12-16[LTO] Make processing of combined module more consistentVitaly Buka
Summary: 1. Use stream 0 only for combined module. Previously if combined module was not processes ThinLTO used the stream for own output. However small changes in input, could trigger combined module and shuffle outputs making life of llvm::LTO harder. 2. Always process combined module and write output to stream 0. Processing empty combined module is cheap and allows llvm::LTO users to avoid implementing processing which is already done in llvm::LTO. Subscribers: mehdi_amini, inglorion, eraman, hiraditya Differential Revision: https://reviews.llvm.org/D41267 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320905 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-15[ThinLTO] Disallow multiple prevailing defsEugene Leviant
https://reviews.llvm.org/D41291 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320825 91177308-0d34-0410-b5e6-96231b3b80d8
2017-12-15[LLVMgold] Don't set undefined symbol as prevailingEugene Leviant
Differential revision: https://reviews.llvm.org/D41113 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320794 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-04[LTO][ThinLTO] Use the linker resolutions to mark global values as dso_local.Sean Fertile
Now that we have a way to mark GlobalValues as local we can use the symbol resolutions that the linker plugin provides as part of lto/thinlto link step to refine the compilers view on what symbols will end up being local. Originally commited as r317374, but reverted in r317395 to update some missed tests. Differential Revision: https://reviews.llvm.org/D35702 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317408 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-04Revert "[LTO][ThinLTO] Use the linker resolutions to mark global values ..."Sean Fertile
Changes more tests then expected on one of the build bots. reverting to investigate. This reverts https://llvm.org/svn/llvm-project/llvm/trunk@317374 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317395 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-03[LTO][ThinLTO] Use the linker resolutions to mark global values as dso_local.Sean Fertile
Now that we have a way to mark GlobalValues as local we can use the symbol resolutions that the linker plugin provides as part of lto/thinlto link step to refine the compilers view on what symbols will end up being local. Differential Revision: https://reviews.llvm.org/D35702 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317374 91177308-0d34-0410-b5e6-96231b3b80d8
2017-11-01LTO: Apply global DCE to ThinLTO modules at LTO opt level 0.Peter Collingbourne
This is necessary because DCE is applied to full LTO modules. Without this change, a reference from a dead ThinLTO global to a dead full LTO global will result in an undefined reference at link time. This problem is only observable when --gc-sections is disabled, or when targeting COFF, as the COFF port of lld requires all symbols to have a definition even if all references are dead (this is consistent with link.exe). This change also adds an EliminateAvailableExternally pass at -O0. This is necessary to handle the situation on Windows where a non-prevailing copy of a linkonce_odr function has an SEH filter function; any such filters must be DCE'd because they will contain a call to the llvm.localrecover intrinsic, passing as an argument the address of the function that the filter belongs to, and llvm.localrecover requires this function to be defined locally. Fixes PR35142. Differential Revision: https://reviews.llvm.org/D39484 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317108 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-23[Support] Rename tool_output_file to ToolOutputFile, NFCReid Kleckner
This class isn't similar to anything from the STL, so it shouldn't use the STL naming conventions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@314050 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-11LowerTypeTests: Add import/export support for targets without absolute ↵Peter Collingbourne
symbol constants. The rationale is the same as for r312967. Differential Revision: https://reviews.llvm.org/D37408 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312968 91177308-0d34-0410-b5e6-96231b3b80d8
2017-09-11WholeProgramDevirt: Add import/export support for targets without absolute ↵Peter Collingbourne
symbol constants. Not all targets support the use of absolute symbols to export constants. In particular, ARM has a wide variety of constant encodings that cannot currently be relocated by linkers. So instead of exporting the constants using symbols, export them directly in the summary. The values of the constants are left as zeroes on targets that support symbolic exports. This may result in more cache misses when targeting those architectures as a result of arbitrary changes in constant values, but this seems somewhat unavoidable for now. Differential Revision: https://reviews.llvm.org/D37407 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@312967 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-09Fix thinlto cache key computation for cfi-icall.Evgeniy Stepanov
Summary: Fixed PR33966. CFI code generation for users (not just callers) of a function depends on whether this function has a jumptable entry or not. This information needs to be encoded in of thinlto cache key. We filter the jumptable list against functions that are actually referenced in the current module. Subscribers: mehdi_amini, inglorion, eraman, hiraditya Differential Revision: https://reviews.llvm.org/D36346 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@310536 91177308-0d34-0410-b5e6-96231b3b80d8
2017-08-03Delete Default and JITDefault code modelsRafael Espindola
IMHO it is an antipattern to have a enum value that is Default. At any given piece of code it is not clear if we have to handle Default or if has already been mapped to a concrete value. In this case in particular, only the target can do the mapping and it is nice to make sure it is always done. This deletes the two default enum values of CodeModel and uses an explicit Optional<CodeModel> when it is possible that it is unspecified. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@309911 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-19LTO: Export functions referenced by the CFI jump table.Peter Collingbourne
If the LowerTypeTests pass decides to add a function to a jump table for CFI, it will add its name to the set cfiFunctionDefs, which among other things will cause the function to be renamed in the ThinLTO backend. One other thing that we must do with such functions is to not internalize them, because the jump table in the full LTO object will contain a reference to the actual function body in the ThinLTO object. This patch handles that by ensuring that we export any functions whose names appear in the cfiFunctionDefs set. Fixes PR33831. Differential Revision: https://reviews.llvm.org/D35605 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308504 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-10Use DenseMap instead std::map for GVSummaryMapTy.Dehao Chen
Summary: This speeds-up thin-link by ~47% for large programs. Reviewers: tejohnson Reviewed By: tejohnson Subscribers: sanjoy, llvm-commits, mehdi_amini Differential Revision: https://reviews.llvm.org/D35148 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307578 91177308-0d34-0410-b5e6-96231b3b80d8
2017-07-06[LTO] Fix the interaction between linker redefined symbols and ThinLTODavide Italiano
This is the same as r304719 but for ThinLTO. The substantial difference is that in this case we don't have whole visibility, just the summary. In the LTO case, when we got the resolution for the input file we could just see if the linker told us whether a symbol was linker redefined (using --wrap or --defsym) and switch the linkage directly for the GV. Here, we have the summary. So, we record that the linkage changed from <whatever it was> to $weakany to prevent IPOs across this symbol boundaries and actually just switch the linkage at FunctionImport time. This patch should also fixes the lld bits (as all the scaffolding for communicating if a symbol is linker redefined should be there & should be the same), but I'll make sure to add some tests there as well. Fixes PR33192. Differential Revision: https://reviews.llvm.org/D35064 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307303 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-30[ORE] Unify spelling as "diagnostics hotness"Brian Gesiak
Summary: To enable profile hotness information in diagnostics output, Clang takes the option `-fdiagnostics-show-hotness` -- that's "diagnostics", with an "s" at the end. Clang also defines `CodeGenOptions::DiagnosticsWithHotness`. LLVM, on the other hand, defines `LLVMContext::getDiagnosticHotnessRequested` -- that's "diagnostic", not "diagnostics". It's a small difference, but it's confusing, typo-inducing, and frustrating. Add a new method with the spelling "diagnostics", and "deprecate" the old spelling. Reviewers: anemet, davidxl Reviewed By: anemet Subscribers: llvm-commits, mehdi_amini Differential Revision: https://reviews.llvm.org/D34864 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306848 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-30[LTO] Remove values from non-prevailing comdatsTeresa Johnson
Summary: When linking a regular LTO module, if it has any non-prevailing values (dropped to available_externally) in comdats, we need to do more than just remove those values from their comdat. We also remove all values from that comdat, so as to avoid leaving an incomplete comdat. This is necessary in case we are compiling in mixed regular and ThinLTO mode, since the resulting regularLTO native object is always linked into the final binary first. We need to prevent the linker from selecting an incomplete comdat that was not the prevailing copy. Fixes PR32980. Reviewers: pcc, rafael Subscribers: mehdi_amini, david2050, llvm-commits, inglorion Differential Revision: https://reviews.llvm.org/D34803 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306826 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-15Silence warning with assertions disabled.Peter Collingbourne
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@305485 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-15Apply summary-based dead stripping to regular LTO modules with summaries.Peter Collingbourne
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
2017-06-08Object: Factor out the code for creating the irsymtab for an arbitrary ↵Peter Collingbourne
bitcode file. This code now lives in lib/Object. The idea is that it can now be reused by IRObjectFile among other things. Differential Revision: https://reviews.llvm.org/D31921 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304958 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-05Symbols re-defined with -wrap and -defsym need to be excluded from inter-Dmitry Mikulin
procedural optimizations to prevent dropping symbols and allow the linker to process re-directs. PR33145: --wrap doesn't work with lto. Differential Revision: https://reviews.llvm.org/D33621 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304719 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-02Move summary dead stripping before regular LTO.Evgeniy Stepanov
This way dead stripping results are recorded in combined summary and can be used in regular LTO passes. Differential Revision: https://reviews.llvm.org/D33615 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304577 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-01[ThinLTO] Move -lto-use-new-pm to llvm-lto2, and change it to -use-new-pm.Tim Shen
Summary: As we teach Clang to use ThinkLTO + new PM, it's good for the users to inject through Config, instead of setting a flag in the LTOBackend library. Move the flag to llvm-lto2. As it moves to llvm-lto2, a new name -use-new-pm seems simpler and as clear. Reviewers: davide, tejohnson Subscribers: mehdi_amini, Prazek, inglorion, eraman, chandlerc, llvm-commits Differential Revision: https://reviews.llvm.org/D33799 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304492 91177308-0d34-0410-b5e6-96231b3b80d8
2017-06-01(NFC) Track global summary liveness in GVFlags.Evgeniy Stepanov
Replace GVFlags::LiveRoot with GVFlags::Live and use that instead of all the DeadSymbols sets. This is refactoring in order to make liveness information available in the RegularLTO pipeline. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304466 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-26[lib/LTO] Don't reinvent the code for switching linkage.Davide Italiano
Differential Revision: https://reviews.llvm.org/D33582 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@304040 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-25LTO: Do summary-based prevailing symbol resolution at --lto-O0.Peter Collingbourne
Prevailing symbol resolution is necessary for correctness. Without this we can end up dropping a referenced linkonce symbol from the link. Differential Revision: https://reviews.llvm.org/D33570 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303939 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-22Infer relocation model from module flags in relocatable LTO link.Evgeniy Stepanov
Fix for PR33096. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303578 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-16IR: Give function GlobalValue::getRealLinkageName() a less misleading name: ↵Peter Collingbourne
dropLLVMManglingEscape(). This function gives the wrong answer on some non-ELF platforms in some cases. The function that does the right thing lives in Mangler.h. To try to discourage people from using this function, give it a different name. Differential Revision: https://reviews.llvm.org/D33162 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303134 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-04Re-apply r302108, "IR: Use pointers instead of GUIDs to represent edges in ↵Peter Collingbourne
the module summary. NFCI." with a fix for the clang backend. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302176 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-04Revert "IR: Use pointers instead of GUIDs to represent edges in the module ↵Eric Liu
summary. NFCI." This reverts commit r302108. This causes crash in clang bootstrap with LTO. Contacted the auther in the original commit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302140 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-04IR: Use pointers instead of GUIDs to represent edges in the module summary. ↵Peter Collingbourne
NFCI. When profiling a no-op incremental link of Chromium I found that the functions computeImportForFunction and computeDeadSymbols were consuming roughly 10% of the profile. The goal of this change is to improve the performance of those functions by changing the map lookups that they were previously doing into pointer dereferences. This is achieved by changing the ValueInfo data structure to be a pointer to an element of the global value map owned by ModuleSummaryIndex, and changing reference lists in the GlobalValueSummary to hold ValueInfos instead of GUIDs. This means that a ValueInfo will take a client directly to the summary list for a given GUID. Differential Revision: https://reviews.llvm.org/D32471 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302108 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-01Bitcode: Make the summary reader responsible for merging. NFCI.Peter Collingbourne
This is to prepare for an upcoming change which uses pointers instead of GUIDs to represent references. Differential Revision: https://reviews.llvm.org/D32469 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301843 91177308-0d34-0410-b5e6-96231b3b80d8
2017-05-01Object: Remove ModuleSummaryIndexObjectFile class.Peter Collingbourne
Differential Revision: https://reviews.llvm.org/D32195 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301832 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-26LTO: Mark undefined module asm symbols as used.Peter Collingbourne
Marking them as used causes them to be considered visible outside of LTO. This prevents the symbols from being internalized or discarded, either by GlobalDCE or by summary-based dead stripping in ThinLTO. This change makes it unnecessary to add these symbols to llvm.compiler.used in the backend, as the symbols are kept alive by virtue of being external, so remove the backend code that handles that. Fixes PR32798. Differential Revision: https://reviews.llvm.org/D32544 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@301438 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-14Object, LTO: Add target triple to irsymtab and LTO API.Peter Collingbourne
Start using it in LLD to avoid needing to read bitcode again just to get the target triple, and in llvm-lto2 to avoid printing symbol table information that is inappropriate for the target. Differential Revision: https://reviews.llvm.org/D32038 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300300 91177308-0d34-0410-b5e6-96231b3b80d8
2017-04-13Support: Add a VCSRevision.h header file.Peter Collingbourne
This is a magic header file supported by the build system that provides a single definition, LLVM_REVISION, containing an LLVM revision identifier, if available. This functionality previously lived in the LTO library, but I am moving it out to lib/Support because I want to also start using it in lib/Object to create the IR symbol table. This change also fixes a bug where LLVM_REVISION was never actually being used in lib/LTO because the macro HAS_LLVM_REVISION was never defined (it was misspelled as HAVE_SVN_VERSION_INC in lib/LTO/CMakeLists.txt, and was only being defined in a non-existent file Version.cpp). I also changed the code to use "git rev-parse --git-dir" to locate the .git directory, instead of looking for it in the LLVM source root directory, which makes this compatible with monorepos as well as git worktrees. Differential Revision: https://reviews.llvm.org/D31985 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@300160 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31LTO: call getRealLinkageName on IRNames before feeding to getGUIDBob Haarman
Summary: GlobalValue has two getGUID methods: an instance method and a static method. The static method takes a string, which is expected to be what GlobalValue::getRealLinkageName() would return. In LTO.cpp, we were not doing this consistently, sometimes passing an IR name instead. This change makes it so that we call getRealLinkageName() first, making the static getGUID return value consistent with the instance method. Without this change, compiling FileCheck with ThinLTO on Windows fails with numerous undefined symbol errors. With the change, it builds successfully. Reviewers: pcc, rnk Reviewed By: pcc Subscribers: tejohnson, mehdi_amini, llvm-commits Differential Revision: https://reviews.llvm.org/D31444 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299268 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31Re-apply r299168 and r299169 now that the libdeps are fixed.Peter Collingbourne
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299184 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31Move llvm::emitLinkerFlagsForGlobalCOFF() to Mangler.Peter Collingbourne
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299183 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31Revert r299168 and r299169 due to library dependency issues.Peter Collingbourne
http://bb.pgr.jp/builders/i686-mingw32-RA-on-linux/builds/25073/steps/build_llvmclang/logs/stdio git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299171 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-31LTO: Reduce memory consumption by creating an in-memory symbol table for ↵Peter Collingbourne
InputFiles. NFCI. Introduce symbol table data structures that can be potentially written to disk, have the LTO library build those data structures using temporarily constructed modules and redirect the LTO library implementation to go through those data structures. This allows us to remove the LLVMContext and Modules owned by InputFile. With this change I measured a peak memory consumption decrease from 5.4GB to 2.8GB in a no-op incremental ThinLTO link of Chromium on Linux. The impact on memory consumption is larger in COFF linkers where we are currently forced to materialize all metadata in order to read linker options. Peak memory consumption linking a large piece of Chromium for Windows with full LTO and debug info decreases from >64GB (OOM) to 15GB. Part of PR27551. Differential Revision: https://reviews.llvm.org/D31364 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@299168 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28More accurate header inclusions. NFC.Peter Collingbourne
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298960 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-28LTO: Replace InputFile::Symbol::getFlags() with predicate accessors. NFC.Peter Collingbourne
This makes the predicates independent of the flag representation and makes the code a little easier to read. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298951 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-10LTO: Hash type identifier resolutions for WholeProgramDevirt.Peter Collingbourne
Differential Revision: https://reviews.llvm.org/D30555 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297514 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-10LTO: Hash type identifier resolutions for LowerTypeTests.Peter Collingbourne
Differential Revision: https://reviews.llvm.org/D30553 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@297513 91177308-0d34-0410-b5e6-96231b3b80d8
2017-03-03LTO: Hash the set of imported symbols for each module.Peter Collingbourne
This set may affect code generation and is sensitive to link order (and possibly in the future to the linker's choice of prevailing symbol), so we need to include it. Differential Revision: https://reviews.llvm.org/D30586 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@296907 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-15[LTO] Add ability to emit assembly to new LTO APITobias Edler von Koch
Summary: Add a field to LTO::Config, CGFileType, to select the file type to emit (object or assembly). This is useful for testing and to implement -save-temps. Reviewers: tejohnson, mehdi_amini, pcc Reviewed By: mehdi_amini Subscribers: davide, llvm-commits Differential Revision: https://reviews.llvm.org/D29475 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295226 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-10[LTO] Share the optimization remarks setup between Thin/Full LTO.Davide Italiano
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294807 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-03IRMover: Merge flags LinkModuleInlineAsm and IsPerformingImport.Peter Collingbourne
Currently these flags are always the inverse of each other, so there is no need to keep them separate. Differential Revision: https://reviews.llvm.org/D29471 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@294016 91177308-0d34-0410-b5e6-96231b3b80d8
2017-02-03Revert "[ThinLTO] Add an auto-hide feature"Mehdi Amini
This reverts commit r293970. After more discussion, this belongs to the linker side and there is no added value to do it at this level. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293993 91177308-0d34-0410-b5e6-96231b3b80d8