Commit Graph

91 Commits

Author SHA1 Message Date
Teresa Johnson 6107a4195d [ThinLTO] Remove functions resolved to available_externally from comdats
Summary:
thinLTOResolveWeakForLinkerModule needs to drop any preempted weak symbols
that were converted to available_externally from comdats, otherwise we
will get a verification failure (since available_externally is a
declaration for the linker, and no declarations can be in a comdat).

Reviewers: mehdi_amini

Subscribers: llvm-commits, mehdi_amini

Differential Revision: https://reviews.llvm.org/D23015

llvm-svn: 278739
2016-08-15 21:00:04 +00:00
Piotr Padlewski 332b3b2210 Don't import variadic functions
Summary:
This patch adds IsVariadicFunction bit to summary in order
to not import variadic functions. Inliner doesn't inline
variadic functions because it is hard to reason about it.

This one small fix improves Importer by about 16%
(going from 86% to 100% of imported functions that are
inlined anywhere)
on some spec benchmarks like 'int' and others.

Reviewers: eraman, mehdi_amini, tejohnson

Subscribers: mehdi_amini, llvm-commits

Differential Revision: https://reviews.llvm.org/D23339

llvm-svn: 278432
2016-08-11 22:13:57 +00:00
Sean Silva fd03ac6a0c Consistently use ModuleAnalysisManager
Besides a general consistently benefit, the extra layer of indirection
allows the mechanical part of https://reviews.llvm.org/D23256 that
requires touching every transformation and analysis to be factored out
cleanly.

Thanks to David for the suggestion.

llvm-svn: 278078
2016-08-09 00:28:38 +00:00
Teresa Johnson 2124157102 [PM] Port FunctionImport Pass to new PM
Summary: Port FunctionImport Pass to new PM.

Reviewers: mehdi_amini, davide

Subscribers: davidxl, llvm-commits

Differential Revision: https://reviews.llvm.org/D22475

llvm-svn: 275916
2016-07-18 21:22:24 +00:00
Piotr Padlewski 3b77612839 Add 'thinlto_src_module' md with asserts or -enable-import-metadata
Summary:
This way the metadata will be only generated when asserts enabled,
or when -enable-import-metadata specified

FIXED missing colon on requires.

Reviewers: tejohnson, eraman, mehdi_amini

Subscribers: mehdi_amini, llvm-commits

Differential Revision: http://reviews.llvm.org/D22167

llvm-svn: 274947
2016-07-08 23:01:49 +00:00
Piotr Padlewski d4b792346c Revert "Add 'thinlto_src_module' md with asserts or -enable-import-metadata"
Reverting because of 17463
http://lab.llvm.org:8011/builders/clang-x86_64-linux-selfhost-modules/builds/17463

This reverts commit d20cb431bba2ba43b4c65a8556cff445bfefbb7c.

llvm-svn: 274946
2016-07-08 22:55:48 +00:00
Piotr Padlewski d6efefa2b8 Add 'thinlto_src_module' md with asserts or -enable-import-metadata
Summary:
This way the metadata will be only generated when asserts enabled,
or when -enable-import-metadata specified

Reviewers: tejohnson, eraman, mehdi_amini

Subscribers: mehdi_amini, llvm-commits

Differential Revision: http://reviews.llvm.org/D22167

llvm-svn: 274938
2016-07-08 21:25:39 +00:00
Piotr Padlewski 6deaa6afae Add 'thinlto_src_module' metadata to imported function
Added metadata to be able to make statistics on how many functions
that have been imported have been removed. Also module name might
be helpfull when debugging.

Reviewers: tejohnson, eraman

Subscribers: mehdi_amini, llvm-commits

Differential Revision: http://reviews.llvm.org/D21943

llvm-svn: 274668
2016-07-06 20:26:25 +00:00
Piotr Padlewski 1f685e0186 NFC changed names in FunctionImport
llvm-svn: 274649
2016-07-06 18:12:23 +00:00
Benjamin Kramer 1afc1de406 Apply another batch of fixes from clang-tidy's performance-unnecessary-value-param.
Contains some manual fixes. No functionality change intended.

llvm-svn: 273047
2016-06-17 20:41:14 +00:00
Teresa Johnson 7ab1f69272 [ThinLTO/gold] Enable summary-based internalization
Summary: Enable existing summary-based importing support in the gold-plugin.

Reviewers: mehdi_amini

Subscribers: llvm-commits, mehdi_amini

Differential Revision: http://reviews.llvm.org/D21080

llvm-svn: 272239
2016-06-09 01:14:13 +00:00
Teresa Johnson 04c9a2d63d [ThinLTO] Refactor ODR resolution and internalization (NFC)
Move the now index-based ODR resolution and internalization routines out
of ThinLTOCodeGenerator.cpp and into either LTO.cpp (index-based
analysis) or FunctionImport.cpp (index-driven optimizations).
This is to enable usage by other linkers.

llvm-svn: 270698
2016-05-25 14:03:11 +00:00
Teresa Johnson 2e03094d45 [ThinLTO] Don't re-analyze callee at same threshold unnecessarily
This should just be a compile-time change. Correct the check for whether
we have already analyzed the callee when making summary based decisions.
There is no need to reprocess one at the same threshold as when it was
last processed.

llvm-svn: 269251
2016-05-11 22:56:19 +00:00
Rafael Espindola f329be8394 Delete mayBeOverridden.
It is the same as isInterposable which seems to be the preferred name.

llvm-svn: 269150
2016-05-11 01:26:06 +00:00
Teresa Johnson 8570fe47ef [ThinLTO] Add option to emit imports files for distributed backends
Summary:
Add support for emission of plaintext lists of the imported files for
each distributed backend compilation. Used for distributed build file
staging.

Invoked with new gold-plugin thinlto-emit-imports-files option, which is
only valid with thinlto-index-only (i.e. for distributed builds), or
from llvm-lto with new -thinlto-action=emitimports value.

Depends on D19556.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D19636

llvm-svn: 269067
2016-05-10 15:54:09 +00:00
Teresa Johnson 84174c3771 Restore "[ThinLTO] Emit individual index files for distributed backends"
This restores commit r268627:
    Summary:
    When launching ThinLTO backends in a distributed build (currently
    supported in gold via the thinlto-index-only plugin option), emit
    an individual index file for each backend process as described here:
    http://lists.llvm.org/pipermail/llvm-dev/2016-April/098272.html

    ...

    Differential Revision: http://reviews.llvm.org/D19556

Address msan failures by avoiding std::prev on map.end(), the
theory is that this is causing issues due to some known UB problems
in __tree.

llvm-svn: 269059
2016-05-10 13:48:23 +00:00
Vitaly Buka 1df2338bb6 Revert "[ThinLTO] Emit individual index files for distributed backends"
MemorySanitizer: use-of-uninitialized-value in lib/Bitcode/Writer/BitcodeWriter.cpp:364:70
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/12544/steps/check-llvm%20msan/logs/stdio

This reverts commit 0c4a898ea550699d1b2f4fe3767251c8f9a48d52.

llvm-svn: 268660
2016-05-05 18:31:00 +00:00
Teresa Johnson 9254ebe3c0 [ThinLTO] Emit individual index files for distributed backends
Summary:
When launching ThinLTO backends in a distributed build (currently
supported in gold via the thinlto-index-only plugin option), emit
an individual index file for each backend process as described here:
http://lists.llvm.org/pipermail/llvm-dev/2016-April/098272.html

The individual index file encodes the summary and module information
required for implementing the importing/exporting decisions made
for a given module in the thin link step.
This is in place of the current mechanism that uses the combined index
to make importing decisions in each back end independently. It is an
enabler for doing global summary based optimizations in the thin link
step (which will be recorded in the individual index files), and reduces
the size of the index that must be sent to each backend process, and
the amount of work to scan it in the backends.

Rather than create entirely new ModuleSummaryIndex structures (and all
the included unique_ptrs) for each backend index file, a map is created
to record all of the GUID and summary pointers needed for a particular
index file. The IndexBitcodeWriter walks this map instead of the full
index (hiding the details of managing the appropriate summary iteration
in a new iterator subclass). This is more efficient than walking the
entire combined index and filtering out just the needed summaries during
each backend bitcode index write.

Depends on D19481.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D19556

llvm-svn: 268627
2016-05-05 13:44:56 +00:00
Mehdi Amini 5b85d8d67b ThinLTO: do not import function whose linkage prevents inlining.
There is not point in importing a "weak" or a "linkonce" function
since we won't be able to inline it anyway.
We already had a targeted check for WeakAny, this is using the
same check on GlobalValue as the inline, i.e.
isMayBeOverriddenLinkage()

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268341
2016-05-03 00:27:28 +00:00
Mehdi Amini 1e918c9cb3 Revert "ThinLTO: do not import function whose linkage prevents inlining."
This reverts commit r268315, the tests are not passing.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268317
2016-05-02 22:26:04 +00:00
Mehdi Amini bda9b2ae9e ThinLTO: do not import function whose linkage prevents inlining.
There is not point in importing a "weak" or a "linkonce" function
since we won't be able to inline it anyway.
We already had a targeted check for WeakAny, this is using the
same check on GlobalValue as the inline, i.e.
isMayBeOverriddenLinkage()

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 268315
2016-05-02 22:11:27 +00:00
Mehdi Amini b4e1e8297b ThinLTO: do not promote GlobalVariable that have a specific section.
Differential Revision: http://reviews.llvm.org/D18298

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 267646
2016-04-27 00:32:13 +00:00
Teresa Johnson c851d216e2 [ThinLTO] Introduce typedef for commonly-used map type (NFC)
Add a typedef for the std::map<GlobalValue::GUID, GlobalValueSummary *>
map that is passed around to identify summaries for values defined in a
particular module. This shortens up declarations in a variety of places.

llvm-svn: 267471
2016-04-25 21:09:51 +00:00
Teresa Johnson 28e457bccd [ThinLTO] Remove GlobalValueInfo class from index
Summary:
Remove the GlobalValueInfo and change the ModuleSummaryIndex to directly
reference summary objects. The info structure was there to support lazy
parsing of the combined index summary objects, which is no longer
needed and not supported.

Reviewers: joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D19462

llvm-svn: 267344
2016-04-24 14:57:11 +00:00
Mehdi Amini cb87494f4c Always traverse GlobalVariable initializer when computing the export list
Summary:
We are always importing the initializer for a GlobalVariable.
So if a GlobalVariable is in the export-list, we pull in any
refs as well.

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D19102

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 267303
2016-04-23 23:29:24 +00:00
Andrew Kaylor aa641a5171 Re-commit optimization bisect support (r267022) without new pass manager support.
The original commit was reverted because of a buildbot problem with LazyCallGraph::SCC handling (not related to the OptBisect handling).

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267231
2016-04-22 22:06:11 +00:00
Vedant Kumar 6013f45f92 Revert "Initial implementation of optimization bisect support."
This reverts commit r267022, due to an ASan failure:

  http://lab.llvm.org:8080/green/job/clang-stage2-cmake-RgSan_check/1549

llvm-svn: 267115
2016-04-22 06:51:37 +00:00
Andrew Kaylor f0f279291c Initial implementation of optimization bisect support.
This patch implements a optimization bisect feature, which will allow optimizations to be selectively disabled at compile time in order to track down test failures that are caused by incorrect optimizations.

The bisection is enabled using a new command line option (-opt-bisect-limit).  Individual passes that may be skipped call the OptBisect object (via an LLVMContext) to see if they should be skipped based on the bisect limit.  A finer level of control (disabling individual transformations) can be managed through an addition OptBisect method, but this is not yet used.

The skip checking in this implementation is based on (and replaces) the skipOptnoneFunction check.  Where that check was being called, a new call has been inserted in its place which checks the bisect limit and the optnone attribute.  A new function call has been added for module and SCC passes that behaves in a similar way.

Differential Revision: http://reviews.llvm.org/D19172

llvm-svn: 267022
2016-04-21 17:58:54 +00:00
Mehdi Amini bda3c97c16 ThinLTO/ModuleLinker: add a flag to not always pull-in linkonce when performing importing
Summary:
The function importer already decided what symbols need to be pulled
in. Also these magically added ones will not be in the export list
for the source module, which can confuse the internalizer for
instance.

Reviewers: tejohnson, rafael

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D19096

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266948
2016-04-21 01:59:39 +00:00
Mehdi Amini 2c719cc117 FunctionImport: make sure we always select the right callee in presence of alias
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266854
2016-04-20 04:17:36 +00:00
Mehdi Amini 6968ef773b ThinLTO: Move alias importing decision on the summary
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266845
2016-04-20 01:04:20 +00:00
Mehdi Amini aeb1e59b71 Minor improvement to debug output for Function Importer (NFC)
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266723
2016-04-19 09:21:30 +00:00
Mehdi Amini 1aafabf752 ThinLTO: Move the ODR resolution to be based purely on the summary.
This is a requirement for the cache handling in D18494

Differential Revision: http://reviews.llvm.org/D18908

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266519
2016-04-16 07:02:16 +00:00
Mehdi Amini 2d28f7aa07 ThinLTO: Make aliases explicit in the summary
To be able to work accurately on the reference graph when taking
decision about internalizing, promoting, renaming, etc. We need
to have the alias information explicit.

Differential Revision: http://reviews.llvm.org/D18836

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266517
2016-04-16 06:56:44 +00:00
Mehdi Amini b5b289339b Revert "Make aliases explicit in the summary"
Inadvertently commited...

This reverts commit e618ec93786d99df2ddf280ad2d5e02f5516cecf.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266215
2016-04-13 17:20:07 +00:00
Mehdi Amini ce744a95fd Make aliases explicit in the summary
Summary:
To be able to work accurately on the reference graph when taking decision
about internalizing, promoting, renaming, etc. We need to have the alias
information explicit.

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18836

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266214
2016-04-13 17:18:42 +00:00
Mehdi Amini ef7555fbb2 Fix FunctionImport export list computation: need to take a reference to a map entry to actually modify it
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 266159
2016-04-13 01:52:32 +00:00
Teresa Johnson c86af3345c [ThinLTO] Only compute imports for current module in FunctionImport pass
Summary:
The function import pass was computing all the imports for all the
modules in the index, and only using the imports for the current module.
Change this to instead compute only for the given module. This means
that the exports list can't be populated, but they weren't being used
anyway.

Longer term, the linker can collect all the imports and export lists
and serialize them out for consumption by the distributed backend
processes which use this pass.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18945

llvm-svn: 266125
2016-04-12 21:13:11 +00:00
Teresa Johnson 2d5487cf44 [ThinLTO] Move summary computation from BitcodeWriter to new pass
Summary:
This is the first step in also serializing the index out to LLVM
assembly.

The per-module summary written to bitcode is moved out of the bitcode
writer and to a new analysis pass (ModuleSummaryIndexWrapperPass).
The pass itself uses a new builder class to compute index, and the
builder class is used directly in places where we don't have a pass
manager (e.g. llvm-as).

Because we are computing summaries outside of the bitcode writer, we no
longer can use value ids created by the bitcode writer's
ValueEnumerator. This required changing the reference graph edge type
to use a new ValueInfo class holding a union between a GUID (combined
index) and Value* (permodule index). The Value* are converted to the
appropriate value ID during bitcode writing.

Also, this enables removal of the BitWriter library's dependence on the
Analysis library that was previously required for the summary computation.

Reviewers: joker.eph

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18763

llvm-svn: 265941
2016-04-11 13:58:45 +00:00
Teresa Johnson 3255eec16c [ThinLTO] Remove unused parameter (NFC)
llvm-svn: 265900
2016-04-10 15:17:26 +00:00
Teresa Johnson 0beb858e97 [ThinLTO] Augment FunctionImport dump with value name to GUID map
Summary:
To aid in debugging, dump out the correlation between value names and
GUID for each source module when it is materialized. This will make it
easier to comprehend the earlier summary-based function importing debug
trace which only has access to and prints the GUIDs.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18556

llvm-svn: 265326
2016-04-04 18:52:23 +00:00
Mehdi Amini ad5741b075 Create a typedef GlobalValue::GUID for uint64_t and RAUW (NFC)
Summary: This should make the code more readable, especially all the map declarations.

Reviewers: tejohnson

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18721

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265215
2016-04-02 05:07:53 +00:00
Mehdi Amini d7ad221c16 Add a module Hash in the bitcode and the combined index, implementing a kind of "build-id"
This is intended to be used for ThinLTO incremental build.

Differential Revision: http://reviews.llvm.org/D18213

This is a recommit of r265095 after fixing the Windows issues.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265111
2016-04-01 05:33:11 +00:00
Mehdi Amini 85fb9e058e Revert "Add support for computing SHA1 in LLVM"
This reverts commit r265096, r265095, and r265094.
Windows build is broken, and the validation does not pass.

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265102
2016-04-01 03:03:21 +00:00
Mehdi Amini 4c2ed3337d Add a module Hash in the bitcode and the combined index, implementing a kind of "build-id"
This is intended to be used for ThinLTO incremental build.

Differential Revision: http://reviews.llvm.org/D18213

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 265095
2016-04-01 01:30:06 +00:00
Teresa Johnson efeae0e210 [ThinLTO] Use new GlobalValue::getGUID helper (NFC)
This was already being used for functions and aliases, was missed when
handling global variables.

llvm-svn: 264734
2016-03-29 14:49:26 +00:00
Teresa Johnson d29478f70e [ThinLTO] Add optional import message and statistics
Summary:
Add a statistic to count the number of imported functions. Also, add a
new -print-imports option to emit a trace of imported functions, that
works even for an NDEBUG build.

Note that emitOptimizationRemark does not work for the above printing as
it expects a Function object and DebugLoc, neither of which we have
with summary-based importing.

This is part 2 of D18487, the first part was committed separately as
r264536.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18487

llvm-svn: 264537
2016-03-27 15:27:30 +00:00
Teresa Johnson 9aae395fa8 [ThinLTO] Don't try to import alias unless aliasee can be imported
With r264503, aliases are now being added to the GlobalsToImport set
even when their aliasees can't be imported due to their linkage type.
While the importing worked correctly (the aliases imported as
declarations) due to the logic in doImportAsDefinition, there is no
point to adding them to the GlobalsToImport set.

Additionally, with D18487 it was resulting in incorrectly printing a
message indicating that the alias was imported.

To avoid this, delay adding aliases to the GlobalsToImport set until
after the linkage type of the aliasee is checked.

This patch is part of D18487.

llvm-svn: 264536
2016-03-27 15:01:11 +00:00
Mehdi Amini 01e321306b ThinLTO: use the callgraph from the combined index to drive the FunctionImporter
Summary:
Now that the summary contains the full reference/call graph, we can
replace the existing function importer that loads and inspect the IR
to iteratively walk the call graph by a traversal based purely on the
summary information. Decouple the actual importing decision from any
IR manipulation.

Reviewers: tejohnson

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18343

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 264503
2016-03-26 05:40:34 +00:00
Mehdi Amini 8d05185a26 Rework linkInModule(), making it oblivious to ThinLTO
Summary:
ThinLTO is relying on linkInModule to import selected function.
However a lot of "magic" was hidden in linkInModule and the IRMover,
who would rename and promote global variables on the fly.

This is moving to an approach where the steps are decoupled and the
client is reponsible to specify the list of globals to import.
As a consequence some test are changed because they were relying on
the previous behavior which was importing the definition of *every*
single global without control on the client side.
Now the burden is on the client to decide if a global has to be imported
or not.

Reviewers: tejohnson

Subscribers: joker.eph, llvm-commits

Differential Revision: http://reviews.llvm.org/D18122

From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 263863
2016-03-19 00:40:31 +00:00