Commit Graph

510 Commits

Author SHA1 Message Date
Peter Collingbourne 264d7c9021 LTO: Remove unnecessary Windows support code.
I empirically verified that open files can in fact be renamed on
Windows with sys::fs::rename, so remove the incorrect code and comment.

llvm-svn: 312683
2017-09-07 00:55:00 +00:00
Peter Collingbourne d0e9c167d8 LTO: Try to open cache files before renaming them.
It appears that a potential race between the cache client and the cache
pruner that I thought was unlikely actually happened in practice [1].
Try to avoid the race condition by opening the temporary file before
renaming it. Do this only on non-Windows platforms because we cannot
rename open files on Windows using the sys::fs::rename function.

[1] https://luci-logdog.appspot.com/v/?s=chromium%2Fbb%2Fchromium.memory%2FLinux_CFI%2F1610%2F%2B%2Frecipes%2Fsteps%2Fcompile%2F0%2Fstdout

Differential Revision: https://reviews.llvm.org/D37410

llvm-svn: 312567
2017-09-05 19:51:38 +00:00
Evgeniy Stepanov 3427d17cf8 Fix thinlto cache key computation for cfi-icall.
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

llvm-svn: 310536
2017-08-09 23:24:07 +00:00
Rafael Espindola 79e238afee Delete Default and JITDefault code models
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.

llvm-svn: 309911
2017-08-03 02:16:21 +00:00
Dehao Chen 3246dc3df1 Fix the bug that parseAAPipeline is not invoked in runNewPMPasses in release compiler.
Summary: The logic is guarded by "assert".

Reviewers: davidxl, davide, chandlerc

Reviewed By: davide, chandlerc

Subscribers: sanjoy, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D36195

llvm-svn: 309787
2017-08-02 03:03:19 +00:00
Dehao Chen 89d3226019 Update the new PM pipeline to make ICP aware if it is SamplePGO build.
Summary: In ThinLTO backend compile, OPTOptions are not set so that the ICP in ThinLTO backend does not know if it is a SamplePGO build, in which profile count needs to be annotated directly on call instructions. This patch cleaned up the PGOOptions handling logic and passes down PGOOptions to ThinLTO backend.

Reviewers: chandlerc, tejohnson, davidxl

Reviewed By: chandlerc

Subscribers: sanjoy, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D36052

llvm-svn: 309780
2017-08-02 01:28:31 +00:00
Peter Collingbourne e776dd9ca2 LTO: Export functions referenced by the CFI jump table.
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

llvm-svn: 308504
2017-07-19 18:18:19 +00:00
Dehao Chen 5d96ee4fab Use DenseMap instead std::map for GVSummaryMapTy.
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

llvm-svn: 307578
2017-07-10 20:12:54 +00:00
Davide Italiano 6a5fbe52fa [LTO] Fix the interaction between linker redefined symbols and ThinLTO
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

llvm-svn: 307303
2017-07-06 19:58:26 +00:00
Brian Gesiak 44e5f6c4ac [ORE] Unify spelling as "diagnostics hotness"
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

llvm-svn: 306848
2017-06-30 18:13:59 +00:00
Teresa Johnson b247ffbaed [LTO] Remove values from non-prevailing comdats
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

llvm-svn: 306826
2017-06-30 14:03:24 +00:00
Teresa Johnson a690e3cea2 [ThinLTO] Remove unnecessary include of Linker.h (NFC)
The ModuleLinker is no longer used by ThinLTO, so this is not needed.

Patch by Benoit Belley <Benoit.Belley@autodesk.com>

llvm-svn: 306028
2017-06-22 16:18:48 +00:00
Peter Collingbourne 7e85b26549 Silence warning with assertions disabled.
llvm-svn: 305485
2017-06-15 17:41:32 +00:00
Peter Collingbourne dbd2fed6a1 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

llvm-svn: 305482
2017-06-15 17:26:13 +00:00
Peter Collingbourne 89061b2224 IR: Replace the "Linker Options" module flag with "llvm.linker.options" named metadata.
The new metadata is easier to manipulate than module flags.

Differential Revision: https://reviews.llvm.org/D31349

llvm-svn: 305227
2017-06-12 20:10:48 +00:00
Peter Collingbourne c00c2b246b Object: Factor out the code for creating the irsymtab for an arbitrary 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

llvm-svn: 304958
2017-06-08 01:26:14 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Dmitry Mikulin db3b87b2c0 Symbols re-defined with -wrap and -defsym need to be excluded from inter-
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

llvm-svn: 304719
2017-06-05 16:24:25 +00:00
Evgeniy Stepanov 659b3bc77d Move summary dead stripping before regular LTO.
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

llvm-svn: 304577
2017-06-02 18:24:17 +00:00
Tim Shen 4e912aa5af [ThinLTO] Move -lto-use-new-pm to llvm-lto2, and change it to -use-new-pm.
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

llvm-svn: 304492
2017-06-01 23:13:44 +00:00
Evgeniy Stepanov 56584bbf16 (NFC) Track global summary liveness in GVFlags.
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.

llvm-svn: 304466
2017-06-01 20:30:06 +00:00
Chandler Carruth 8b3be4e59d [PM/ThinLTO] Port the ThinLTO pipeline (both components) to the new PM.
Based on the original patch by Davide, but I've adjusted the API exposed
to just be different entry points rather than exposing more state
parameters. I've factored all the common logic out so that we don't have
any duplicate pipelines, we just stitch them together in different ways.
I think this makes the build easier to reason about and understand.

This adds a direct method for getting the module simplification pipeline
as well as a method to get the optimization pipeline. While not my
express goal, this seems nice and gives a good place comment about the
restrictions that are imposed on them.

I did make some minor changes to the way the pipelines are structured
here, but hopefully not ones that are significant or controversial:

1) I sunk the PGO indirect call promotion to only be run when we have
   PGO enabled (or as part of the special ThinLTO pipeline).

2) I made the extra GlobalOpt run in ThinLTO just happen all the time
   and at a slightly more powerful place (before we remove available
   externaly functions). This seems like general goodness and not a big
   compile time sink, so it didn't make sense to *only* use it in
   ThinLTO. Fewer differences in the pipeline makes everything simpler
   IMO.

3) I hoisted the ThinLTO stop point pre-link above the the RPO function
   attr inference. The RPO inference won't infer anything terribly
   meaningful pre-link (recursiveness?) so it didn't make a lot of
   sense. But if the placement of RPO inference starts to matter, we
   should move it to the canonicalization phase anyways which seems like
   a better place for it (and there is a FIXME to this effect!). But
   that seemed a bridge too far for this patch.

If we ever need to parameterize these pipelines more heavily, we can
always sink the logic to helper functions with parameters to keep those
parameters out of the public API. But the changes above seemed minor
that we could possible get away without the parameters entirely.

I added support for parsing 'thinlto' and 'thinlto-pre-link' names in
pass pipelines to make it easy to test these routines and play with them
in larger pipelines. I also added a really basic manifest of passes test
that will show exactly how the pipelines behave and work as well as
making updates to them clear.

Lastly, this factoring does introduce a nesting layer of module pass
managers in the default pipeline. I don't think this is a big deal and
the flexibility of decoupling the pipelines seems easily worth it.

Differential Revision: https://reviews.llvm.org/D33540

llvm-svn: 304407
2017-06-01 11:39:39 +00:00
Davide Italiano d4db116af8 [lib/LTO] Don't reinvent the code for switching linkage.
Differential Revision:  https://reviews.llvm.org/D33582

llvm-svn: 304040
2017-05-26 21:56:14 +00:00
Peter Collingbourne f87197ad91 LTO: Do summary-based prevailing symbol resolution at --lto-O0.
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

llvm-svn: 303939
2017-05-25 23:40:11 +00:00
Evgeniy Stepanov b9f1b014e1 Infer relocation model from module flags in relocatable LTO link.
Fix for PR33096.

llvm-svn: 303578
2017-05-22 21:11:35 +00:00
Adrian Prantl 981a799896 Revert "Revert "ThinLTO: Verify bitcode before lauching the ThinLTOCodeGenerator.""
This reapplies commit r303438 modified to not verify cross-imported
bitcode in FunctionImporter.

rdar://problem/31233625

Differential Revision: https://reviews.llvm.org/D33370

llvm-svn: 303470
2017-05-20 00:00:08 +00:00
Adrian Prantl 660437975b Revert "ThinLTO: Verify bitcode before lauching the ThinLTOCodeGenerator."
This reverts commit r303438 while deliberating buildbot breakage.

llvm-svn: 303467
2017-05-19 23:32:21 +00:00
Adrian Prantl f9ab9bfc39 ThinLTO: Verify bitcode before lauching the ThinLTOCodeGenerator.
rdar://problem/31233625

Differential Revision: https://reviews.llvm.org/D33151

llvm-svn: 303438
2017-05-19 17:55:02 +00:00
Akira Hatanaka b10bff1183 [ThinLTO] Do not assert when adding a module with a different but
compatible target triple

Currently, an assertion fails in ThinLTOCodeGenerator::addModule when
the target triple of the module being added doesn't match that of the
one stored in TMBuilder. This patch relaxes the constraint and makes
changes to allow target triples that only differ in their version
numbers on Apple platforms, similarly to what r228999 did.

rdar://problem/30133904

Differential Revision: https://reviews.llvm.org/D33291

llvm-svn: 303326
2017-05-18 03:52:29 +00:00
James Henderson 852f6fde01 [LTO] Print time-passes information at conclusion of LTO codegen
The information collected when requested by -time-passes is only printed when
llvm_shutdown is called at the moment. This means that when linking against the LTO
library dynamically and using the C interface, it is not possible to see the timing
information, because llvm_shutdown cannot be called. This change modifies the LTO
code generation functions for both regular LTO and thin LTO to explicitly print and
reset the timing information.

I have tested that this works with our proprietary linker. However, as this relies
on a specific method of building and linking against the LTO library, I'm not sure
how or if this can be tested in the LLVM testsuite.

Reviewed by: mehdi_amini

Differential Revision: https://reviews.llvm.org/D32803

llvm-svn: 303152
2017-05-16 09:43:21 +00:00
Peter Collingbourne 6f0ecca3b5 IR: Give function GlobalValue::getRealLinkageName() a less misleading name: 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

llvm-svn: 303134
2017-05-16 00:39:01 +00:00
Adrian Prantl 1fa362f811 LTO: Don't verify modules twice in verifyMergedModuleOnce
Differential Revision: https://reviews.llvm.org/D33140

llvm-svn: 302951
2017-05-12 21:38:32 +00:00
Teresa Johnson 94624aca2a Ensure non-null ProfileSummaryInfo passed to ModuleSummaryIndex builder
This fixes a ubsan bot failure after r302597, which made getProfileCount
non-static, but ended up invoking it on a null ProfileSummaryInfo object
in some cases from buildModuleSummaryIndex.

Most testing passed because the non-static getProfileCount currently
doesn't access any member variables, but I found this when testing a
follow on patch (D32877) that adds a member variable access.

llvm-svn: 302705
2017-05-10 18:52:16 +00:00
Peter Collingbourne 9667b91b13 Re-apply r302108, "IR: Use pointers instead of GUIDs to represent edges in the module summary. NFCI."
with a fix for the clang backend.

llvm-svn: 302176
2017-05-04 18:03:25 +00:00
Eric Liu f6039f255e Revert "IR: Use pointers instead of GUIDs to represent edges in the module summary. NFCI."
This reverts commit r302108. This causes crash in clang bootstrap with LTO.

Contacted the auther in the original commit.

llvm-svn: 302140
2017-05-04 11:49:39 +00:00
Peter Collingbourne 5f85a9deda IR: Use pointers instead of GUIDs to represent edges in the module summary. 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

llvm-svn: 302108
2017-05-04 03:36:16 +00:00
Peter Collingbourne 74d22dd7dc Bitcode: Make the summary reader responsible for merging. NFCI.
This is to prepare for an upcoming change which uses pointers instead of
GUIDs to represent references.

Differential Revision: https://reviews.llvm.org/D32469

llvm-svn: 301843
2017-05-01 22:04:36 +00:00
Peter Collingbourne c15d60b772 Object: Remove ModuleSummaryIndexObjectFile class.
Differential Revision: https://reviews.llvm.org/D32195

llvm-svn: 301832
2017-05-01 20:42:32 +00:00
Peter Collingbourne fa58f7528e LTO: Mark undefined module asm symbols as used.
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

llvm-svn: 301438
2017-04-26 17:53:39 +00:00
Peter Collingbourne 8446f1fe6a Object, LTO: Add target triple to irsymtab and LTO API.
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

llvm-svn: 300300
2017-04-14 02:55:06 +00:00
Peter Collingbourne 942fa56f40 Support: Add a VCSRevision.h header file.
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

llvm-svn: 300160
2017-04-13 01:26:12 +00:00
Bob Haarman d6aea71957 LTO: call getRealLinkageName on IRNames before feeding to getGUID
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

llvm-svn: 299268
2017-03-31 21:56:30 +00:00
Peter Collingbourne 7b30f16c9f Re-apply r299168 and r299169 now that the libdeps are fixed.
llvm-svn: 299184
2017-03-31 04:47:07 +00:00
Peter Collingbourne c66018e247 Move llvm::emitLinkerFlagsForGlobalCOFF() to Mangler.
llvm-svn: 299183
2017-03-31 04:46:50 +00:00
Peter Collingbourne 2e0ffe9858 Move llvm::canBeOmittedFromSymbolTable() to Analysis.
llvm-svn: 299182
2017-03-31 04:46:31 +00:00
Peter Collingbourne f10698b940 Revert r299168 and r299169 due to library dependency issues.
http://bb.pgr.jp/builders/i686-mingw32-RA-on-linux/builds/25073/steps/build_llvmclang/logs/stdio

llvm-svn: 299171
2017-03-31 02:44:50 +00:00
Peter Collingbourne d9717aa0e4 LTO: Reduce memory consumption by creating an in-memory symbol table for 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

llvm-svn: 299168
2017-03-31 02:28:30 +00:00
Peter Collingbourne 192d8520de More accurate header inclusions. NFC.
llvm-svn: 298960
2017-03-28 23:35:34 +00:00
Peter Collingbourne 0d56b959ad LTO: Replace InputFile::Symbol::getFlags() with predicate accessors. NFC.
This makes the predicates independent of the flag representation
and makes the code a little easier to read.

llvm-svn: 298951
2017-03-28 22:31:35 +00:00
Mehdi Amini b5a46c1f45 Add support for -fno-builtin to LTO and ThinLTO to libLTO
Reviewers: tejohnson, pcc

Subscribers: Prazek, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D30791

llvm-svn: 298936
2017-03-28 18:55:44 +00:00