Commit Graph

72 Commits

Author SHA1 Message Date
Caroline Tice 3dea3f9e0a Pass code-model through Module IR to LTO which will use it.
Currently the code-model does not get saved in the module IR,
so if a code model is specified when compiling with LTO,
it gets lost and is not propagated properly to LTO. This patch,
along with one for the front end, fixes that.

Differential Revision: https://reviews.llvm.org/D52322

llvm-svn: 342760
2018-09-21 18:41:31 +00:00
Teresa Johnson 28023dbed7 [ThinLTO] Enable ThinLTO WholeProgramDevirt and LowerTypeTests in new PM
Summary:
Enable these passes for CFI and WPD in ThinLTO and LTO with the new pass
manager. Add a couple of tests for both PMs based on the clang tests
tools/clang/test/CodeGen/thinlto-distributed-cfi*.ll, but just test
through llvm-lto2 and not with distributed ThinLTO.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, eraman, steven_wu, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D49429

llvm-svn: 337461
2018-07-19 14:51:32 +00:00
Peter Collingbourne 3aa30e8062 IRGen: Write .dwo files when -split-dwarf-file is used together with -fthinlto-index.
Differential Revision: https://reviews.llvm.org/D47597

llvm-svn: 333677
2018-05-31 18:25:59 +00:00
Peter Collingbourne 274c4f7ab4 Fix a make_unique ambiguity.
llvm-svn: 332889
2018-05-21 20:56:28 +00:00
Peter Collingbourne c5a9765cea LTO: Replace split dwarf implementation that uses objcopy with one that uses direct emission.
Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47091

llvm-svn: 332884
2018-05-21 20:26:49 +00:00
Peter Collingbourne 9a45114b3c CodeGen: Add a dwo output file argument to addPassesToEmitFile and hook it up to dwo output.
Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47089

llvm-svn: 332881
2018-05-21 20:16:41 +00:00
Teresa Johnson 81d9207317 [LTO] Handle Task=-1 passed to addSaveTemps
Summary:
This change is necessary for D46464, which will pass -1 as the Task
ID for distributed backends, so that the save temps files don't end
up with "4294967295" in their path. For distributed back ends, when -1
is passed, don't append any Task ID.

An existing test (tools/clang/test/CodeGen/thinlto_backend.ll) will
fail without this change after D46464.

Reviewers: pcc

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D46488

llvm-svn: 331591
2018-05-05 14:37:20 +00:00
Teresa Johnson 85cc298c1a [ThinLTO] Add support for optimization remarks to thinBackend
Summary:
Support was added to the regular LTO backend, but not thinBackend.
This patch adds that support.

Reviewers: pcc, davide

Subscribers: mehdi_amini, inglorion, llvm-commits

Differential Revision: https://reviews.llvm.org/D46376

llvm-svn: 331481
2018-05-03 20:24:12 +00:00
Yunlian Jiang bd200b9ff6 Enable debug fission for thinLTO linked via gold-plugin
Summary: This enables debug fission on implicit ThinLTO when linked with gold. It will put the .dwo files in a directory specified by user. 

Reviewers: tejohnson, pcc, dblaikie

Reviewed By: pcc

Subscribers: JDevlieghere, mehdi_amini, inglorion

Differential Revision: https://reviews.llvm.org/D44792

llvm-svn: 329988
2018-04-13 05:03:28 +00:00
Bob Haarman fb2d342299 Revert "[LTO] Support filtering by hotness threshold"
This reverts commit 1f3bd185c53beb6aa68446974b7e80837abd6ef0 (r326107)
because it fails
ThinLTO/X86/diagnostic-handler-remarks-with-hotness.ll.

llvm-svn: 326975
2018-03-08 01:13:10 +00:00
Adam Nemet b4ce3573c4 [LTO] Support filtering by hotness threshold
This wires up -pass-remarks-hotness-threshold to LTO and ThinLTO.

Next is to change the clang driver to pass this
with -fdiagnostics-hotness-threshold.

Differential Revision: https://reviews.llvm.org/D41465

llvm-svn: 326107
2018-02-26 18:37:45 +00:00
Rafael Espindola 6a86e25d90 Pass a reference to a module to the bitcode writer.
This simplifies most callers as they are already using references or
std::unique_ptr.

llvm-svn: 325155
2018-02-14 19:11:32 +00:00
Teresa Johnson 791c98e4c8 [ThinLTO] Remove dead and dropped symbol declarations when possible
Summary:
Removing the dropped symbols will prevent indirect call promotion in the
ThinLTO Backend from adding a new reference to a symbol, which can
result in linker unsats. This can happen when we compile with a sample
profile collected from one binary by used for another, which may have
profiled targets that aren't used in the new binary.

Note that until dropDeadSymbols handles variables and aliases (in
progress), we may not be able to remove the declaration and can still
have an issue.

Reviewers: grimar, davidxl

Subscribers: mehdi_amini, inglorion, llvm-commits, eraman

Differential Revision: https://reviews.llvm.org/D42816

llvm-svn: 324299
2018-02-06 00:43:39 +00:00
Teresa Johnson 5a95c47730 [ThinLTO] Convert dead alias to declarations
Summary:
This complements the fixes in r323633 and r324075 which drop the
definitions of dead functions and variables, respectively.

Fixes PR36208.

Reviewers: grimar, rafael

Subscribers: mehdi_amini, llvm-commits, inglorion

Differential Revision: https://reviews.llvm.org/D42856

llvm-svn: 324242
2018-02-05 15:44:27 +00:00
George Rimar f5de271a92 [LTO] - Simplify. NFC.
llvm-svn: 324076
2018-02-02 12:21:26 +00:00
George Rimar 76c5fae2a0 [ThinLTO] - Fix for "ThinLTO inlines variables that should be discarded".
This fixes PR36187.

Patch teaches ThinLTO to drop non-prevailing variables, 
just like we recently did for functions (in r323633).

Differential revision: https://reviews.llvm.org/D42798

llvm-svn: 324075
2018-02-02 12:17:33 +00:00
George Rimar eaf5172ca6 [ThinLTO] - Stop internalizing and drop non-prevailing symbols.
Implementation marks non-prevailing symbols as not live in the summary.
Then them are dropped in backends.

Fixes https://bugs.llvm.org/show_bug.cgi?id=35938

Differential revision: https://reviews.llvm.org/D42107

llvm-svn: 323633
2018-01-29 08:03:30 +00:00
Eugene Leviant 28d8a49f42 [ThinLTO] Re-commit of dot dumper after test fix
llvm-svn: 323116
2018-01-22 13:35:40 +00:00
Eugene Leviant 72b9bdb71a Temporarily revert r323062 to investigate buildbot failures
llvm-svn: 323065
2018-01-21 10:22:19 +00:00
Eugene Leviant 453c976a63 [ThinLTO] Implement summary visualizer
Differential revision: https://reviews.llvm.org/D41297

llvm-svn: 323062
2018-01-21 07:27:32 +00:00
Reid Kleckner 3fc649cb76 [Support] Rename tool_output_file to ToolOutputFile, NFC
This class isn't similar to anything from the STL, so it shouldn't use
the STL naming conventions.

llvm-svn: 314050
2017-09-23 01:03:17 +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
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
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
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
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 192d8520de More accurate header inclusions. NFC.
llvm-svn: 298960
2017-03-28 23:35:34 +00:00
Peter Collingbourne f7691d8b41 IPO: Const correctness for summaries passed into passes.
Pass const qualified summaries into importers and unqualified summaries into
exporters. This lets us const-qualify the summary argument to thinBackend.

Differential Revision: https://reviews.llvm.org/D31230

llvm-svn: 298534
2017-03-22 18:22:59 +00:00
Teresa Johnson d820447212 Perform symbol binding for .symver versioned symbols
Summary:
In a .symver assembler directive like:
.symver name, name2@@nodename
"name2@@nodename" should get the same symbol binding as "name".

While the ELF object writer is updating the symbol binding for .symver
aliases before emitting the object file, not doing so when the module
inline assembly is handled by the RecordStreamer is causing the wrong
behavior in *LTO mode.

E.g. when "name" is global, "name2@@nodename" must also be marked as
global. Otherwise, the symbol is skipped when iterating over the LTO
InputFile symbols (InputFile::Symbol::shouldSkip). So, for example,
when performing any *LTO via the gold-plugin, the versioned symbol
definition is not recorded by the plugin and passed back to the
linker. If the object was in an archive, and there were no other symbols
needed from that object, the object would not be included in the final
link and references to the versioned symbol are undefined.

The llvm-lto2 tests added will give an error about an unused symbol
resolution without the fix.

Reviewers: rafael, pcc

Reviewed By: pcc

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D30485

llvm-svn: 297332
2017-03-09 00:19:49 +00:00
Tobias Edler von Koch f454b9eadf [LTO] Add ability to emit assembly to new LTO API
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

llvm-svn: 295226
2017-02-15 20:36:36 +00:00
Davide Italiano 20a895c4be [LTO] Make sure we flush buffers to work around linker shenanigans.
lld, at least, doesn't call global destructors by default (unless
--full-shutdown is passed) because it's, allegedly, expensive.

llvm-svn: 294953
2017-02-13 14:39:51 +00:00
Davide Italiano ebd471974a [lib/LTO] Initial support for optimization remarks in the new API.
llvm-svn: 294882
2017-02-12 03:31:30 +00:00
Davide Italiano 0dd200e04d [LTO] Teach lib/LTO about the new pass manager.
Differential Revision:  https://reviews.llvm.org/D28997

llvm-svn: 292864
2017-01-24 00:58:24 +00:00
Peter Collingbourne e02b74e294 IPO, LTO: Plumb the summary from the LTO API into the pass manager.
Differential Revision: https://reviews.llvm.org/D28840

llvm-svn: 292661
2017-01-20 22:18:52 +00:00
Chandler Carruth 3bab7e1a79 [PM] Separate the LoopAnalysisManager from the LoopPassManager and move
the latter to the Transforms library.

While the loop PM uses an analysis to form the IR units, the current
plan is to have the PM itself establish and enforce both loop simplified
form and LCSSA. This would be a layering violation in the analysis
library.

Fundamentally, the idea behind the loop PM is to *transform* loops in
addition to running passes over them, so it really seemed like the most
natural place to sink this was into the transforms library.

We can't just move *everything* because we also have loop analyses that
rely on a subset of the invariants. So this patch splits the the loop
infrastructure into the analysis management that has to be part of the
analysis library, and the transform-aware pass manager.

This also required splitting the loop analyses' printer passes out to
the transforms library, which makes sense to me as running these will
transform the code into LCSSA in theory.

I haven't split the unittest though because testing one component
without the other seems nearly intractable.

Differential Revision: https://reviews.llvm.org/D28452

llvm-svn: 291662
2017-01-11 09:43:56 +00:00
Teresa Johnson a61f5e3796 [ThinLTO] Import composite types as declarations
Summary:
When reading the metadata bitcode, create a type declaration when
possible for composite types when we are importing. Doing this in
the bitcode reader saves memory. Also it works naturally in the case
when the type ODR map contains a definition for the same composite type
because it was used in the importing module (buildODRType will
automatically use the existing definition and not create a type
declaration).

For Chromium built with -g2, this reduces the aggregate size of the
generated native object files by 66% (from 31G to 10G). It reduced
the time through the ThinLTO link and backend phases by about 20% on
my machine.

Reviewers: mehdi_amini, dblaikie, aprantl

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D27775

llvm-svn: 289993
2016-12-16 21:25:01 +00:00
Dehao Chen 2797800595 Pass sample pgo flags to thinlto.
Summary: ThinLTO needs to invoke SampleProfileLoader pass during link time in order to annotate profile correctly after module importing.

Reviewers: davidxl, mehdi_amini, tejohnson

Subscribers: pcc, davide, llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D27790

llvm-svn: 289957
2016-12-16 16:48:46 +00:00
Davide Italiano 2ceb628f36 [LTO] Reject modules without datalayout.
Also, udpate the ~60 failing tests in the tree which did
not contain a valid datalayout.
This fixes PR31123. lld will be updated in a following patch,
immediately after this is committed.

Differential Revision:  https://reviews.llvm.org/D27082

llvm-svn: 289719
2016-12-14 21:57:04 +00:00
Peter Collingbourne 1a0720e8c4 LTO: Add support for multi-module bitcode files.
Differential Revision: https://reviews.llvm.org/D27313

llvm-svn: 289621
2016-12-14 01:17:59 +00:00
Peter Collingbourne 863cbfbeba Object: Extract a ModuleSymbolTable class from IRObjectFile.
This class represents a symbol table built from in-memory IR. It provides
access to GlobalValues and should only be used if such access is required
(e.g. in the LTO implementation). We will eventually change IRObjectFile
to read from a bitcode symbol table rather than using ModuleSymbolTable,
so it would not be able to expose the module.

Differential Revision: https://reviews.llvm.org/D27073

llvm-svn: 288319
2016-12-01 06:51:47 +00:00
Davide Italiano 8812f28f47 [lib/LTO] Rename few instances of Lto to LTO.
llvm-svn: 287840
2016-11-24 00:23:09 +00:00
Peter Collingbourne d9445c49ad Bitcode: Change module reader functions to return an llvm::Expected.
Differential Revision: https://reviews.llvm.org/D26562

llvm-svn: 286752
2016-11-13 07:00:17 +00:00
Teresa Johnson ad17679abd Split Bitcode/ReaderWriter.h into separate reader and writer headers
Summary:
Split ReaderWriter.h which contains the APIs into both the BitReader and
BitWriter libraries into BitcodeReader.h and BitcodeWriter.h.

This is to address Chandler's concern about sharing the same API header
between multiple libraries (BitReader and BitWriter). That concern is
why we create a single bitcode library in our downstream build of clang,
which led to r286297 being reverted as it added a dependency that
created a cycle only when there is a single bitcode library (not two as
in upstream).

Reviewers: mehdi_amini

Subscribers: dlj, mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D26502

llvm-svn: 286566
2016-11-11 05:34:58 +00:00
Mehdi Amini 41af43092c Make the Error class constructor protected
This is forcing to use Error::success(), which is in a wide majority
of cases a lot more readable.

Differential Revision: https://reviews.llvm.org/D26481

llvm-svn: 286561
2016-11-11 04:28:40 +00:00
Peter Collingbourne 7f00d0a125 Bitcode: Change the materializer interface to return llvm::Error.
Differential Revision: https://reviews.llvm.org/D26439

llvm-svn: 286382
2016-11-09 17:49:19 +00:00
Peter Collingbourne e2dcf7c3a1 IR, Bitcode: Change bitcode reader to no longer own its memory buffer.
Unique ownership is just one possible ownership pattern for the memory buffer
underlying the bitcode reader. In practice, as this patch shows, ownership can
often reside at a higher level. With the upcoming change to allow multiple
modules in a single bitcode file, it will no longer be appropriate for
modules to generally have unique ownership of their memory buffer.

The C API exposes the ownership relation via the LLVMGetBitcodeModuleInContext
and LLVMGetBitcodeModuleInContext2 functions, so we still need some way for
the module to own the memory buffer. This patch does so by adding an owned
memory buffer field to Module, and using it in a few other places where it
is convenient.

Differential Revision: https://reviews.llvm.org/D26384

llvm-svn: 286214
2016-11-08 06:03:43 +00:00
Benjamin Kramer 4c2582ad78 Reduce global namespace pollution. NFC.
llvm-svn: 284521
2016-10-18 19:39:31 +00:00
Peter Collingbourne f75609e015 Add explanatory comment.
llvm-svn: 282678
2016-09-29 03:29:28 +00:00
Peter Collingbourne 0d5636e517 LTO: Fix use-after-scope error.
llvm-svn: 282665
2016-09-29 01:28:36 +00:00