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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303152 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@302705 91177308-0d34-0410-b5e6-96231b3b80d8
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
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
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
This is a safeguard against data loss if the user specifies a directory
that is not a cache directory. Teach the existing cache pruning clients
to create files with appropriate names.
Differential Revision: https://reviews.llvm.org/D31109
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@298271 91177308-0d34-0410-b5e6-96231b3b80d8
We can't assume that the `const char *` provided through libLTO has a
lifetime that expands beyond the codegenerator itself.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295018 91177308-0d34-0410-b5e6-96231b3b80d8
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
When a symbol is not exported outside of the
DSO, it is can be hidden. Usually we try to internalize
as much as possible, but it is not always possible, for
instance a symbol can be referenced outside of the LTO
unit, or there can be cross-module reference in ThinLTO.
This is a recommit of r293912 after fixing build failures,
and a recommit of r293918 after fixing LLD tests.
Differential Revision: https://reviews.llvm.org/D28978
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293970 91177308-0d34-0410-b5e6-96231b3b80d8
When a symbol is not exported outside of the
DSO, it is can be hidden. Usually we try to internalize
as much as possible, but it is not always possible, for
instance a symbol can be referenced outside of the LTO
unit, or there can be cross-module reference in ThinLTO.
This is a recommit of r293912 after fixing build failures.
Differential Revision: https://reviews.llvm.org/D28978
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293918 91177308-0d34-0410-b5e6-96231b3b80d8
When a symbol is not exported outside of the
DSO, it is can be hidden. Usually we try to internalize
as much as possible, but it is not always possible, for
instance a symbol can be referenced outside of the LTO
unit, or there can be cross-module reference in ThinLTO.
Differential Revision: https://reviews.llvm.org/D28978
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293912 91177308-0d34-0410-b5e6-96231b3b80d8
This has been fixed in the "new" LTO API used by Gold/LLD, this is
fixing the same issue in the libLTO API used by ld64 (amongst other)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291518 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Using the linker-supplied list of "preserved" symbols, we can compute
the list of "dead" symbols, i.e. the one that are not reachable from
a "preserved" symbol transitively on the reference graph.
Right now we are using this information to mark these functions as
non-eligible for import.
The impact is two folds:
- Reduction of compile time: we don't import these functions anywhere
or import the function these symbols are calling.
- The limited number of import/export leads to better internalization.
Patch originally by Mehdi Amini.
Reviewers: mehdi_amini, pcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D23488
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@291177 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289993 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The motivation is to support better the -object_path_lto option on
Darwin. The linker needs to write down the generate object files on
disk for later use by lldb or dsymutil (debug info are not present
in the final binary). We're moving this into libLTO so that we can
be smarter when a cache is enabled and hard-link when possible
instead of duplicating the files.
Reviewers: tejohnson, deadalnix, pcc
Subscribers: dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D27507
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289631 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This will also be added to the LTO API, right now this will
bring ThinLTO on par with Monolithic LTO on Darwin.
Reviewers: anemet
Subscribers: tejohnson, llvm-commits
Differential Revision: https://reviews.llvm.org/D26886
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@287450 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We have always speculatively promoted all renamable local values
(except const non-address taken variables) for both the exporting
and importing module. We would then internalize them back based on
the ThinLink results if they weren't actually exported. This is
inefficient, and results in unnecessary renames. It also meant we
had to check the non-renamability of a value in the summary, which
was already checked during function importing analysis in the ThinLink.
Made renameModuleForThinLTO (which does the promotion/renaming) instead
use the index when exporting, to avoid unnecessary renames/promotions.
For importing modules, we can simply promoted all values as any local
we import by definition is exported and needs promotion.
This required changes to the method used by the FunctionImport pass
(only invoked from 'opt' for testing) and when invoked from llvm-link,
since neither does a ThinLink. We simply conservatively mark all locals
in the index as promoted, which preserves the current aggressive
promotion behavior.
I also needed to change an llvm-lto based test where we had previously
been aggressively promoting values that weren't importable (aliasees),
but now will not promote.
Reviewers: mehdi_amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D26467
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286871 91177308-0d34-0410-b5e6-96231b3b80d8
The functions getBitcodeTargetTriple(), isBitcodeContainingObjCCategory(),
getBitcodeProducerString() and hasGlobalValueSummary() now return errors
via their return value rather than via the diagnostic handler.
To make this work, re-implement these functions using non-member functions
so that they can be used without the LLVMContext required by BitcodeReader.
Differential Revision: https://reviews.llvm.org/D26532
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286623 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@286566 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This is a follow-up to D25416. It removes all usages of TimeValue from
llvm/Support library (except for the actual TimeValue declaration), and replaces
them with appropriate usages of std::chrono. To facilitate this, I have added
small utility functions for converting time points and durations into appropriate
OS-specific types (FILETIME, struct timespec, ...).
Reviewers: zturner, mehdi_amini
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25730
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284966 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Changes default backend parallelism from thread::hardware_concurrency to
the new llvm::heavyweight_hardware_concurrency, which for X86 Linux
defaults to the number of physical cores (and will fall back to
thread::hardware_concurrency otherwise). This avoid oversubscribing
the physical cores using hyperthreading.
Reviewers: mehdi_amini, pcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D25775
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@284618 91177308-0d34-0410-b5e6-96231b3b80d8
We need to add an entry in the combined-index for modules that have
a hash but otherwise empty summary, this is needed so that we can
get the hash for the module.
Also, if no entry is present in the combined index for a module, we
need to skip it when trying to compute a cache entry.
Differential Revision: https://reviews.llvm.org/D25300
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283654 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch improves thinlto importer
by importing 3x larger functions that are called from hot block.
I compared performance with the trunk on spec, and there
were about 2% on povray and 3.33% on milc. These results seems
to be consistant and match the results Teresa got with her simple
heuristic. Some benchmarks got slower but I think they are just
noisy (mcf, xalancbmki, omnetpp)- running the benchmarks again with
more iterations to confirm. Geomean of all benchmarks including the noisy ones
were about +0.02%.
I see much better improvement on google branch with Easwaran patch
for pgo callsite inlining (the inliner actually inline those big functions)
Over all I see +0.5% improvement, and I get +8.65% on povray.
So I guess we will see much bigger change when Easwaran patch will land
(it depends on new pass manager), but it is still worth putting this to trunk
before it.
Implementation details changes:
- Removed CallsiteCount.
- ProfileCount got replaced by Hotness
- hot-import-multiplier is set to 3.0 for now,
didn't have time to tune it up, but I see that we get most of the interesting
functions with 3, so there is no much performance difference with higher, and
binary size doesn't grow as much as with 10.0.
Reviewers: eraman, mehdi_amini, tejohnson
Subscribers: mehdi_amini, llvm-commits
Differential Revision: https://reviews.llvm.org/D24638
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282437 91177308-0d34-0410-b5e6-96231b3b80d8
directly produce the index as the value type result.
This requires making the index movable which is straightforward. It
greatly simplifies things by allowing us to completely avoid the builder
API and the layers of abstraction inherent there. Instead both pass
managers can directly construct these when run by value. They still
won't be constructed truly eagerly thanks to the optional in the legacy
PM. The code that directly builds the index can also just share a direct
function.
A notable change here is that the result type of the analysis for the
new PM is no longer a reference type. This was really problematic when
making changes to how we handle result types to make our interface
requirements *much* more strict and precise. But I think this is an
overall improvement.
Differential Revision: https://reviews.llvm.org/D23701
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@279216 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Multiple APIs were taking a StringMap for the ImportLists containing
the entries for for all the modules while operating on a single entry
for the current module. Instead we can pass the desired ModuleImport
directly. Also some of the APIs were not const, I believe just to be
able to use operator[] on the StringMap.
Reviewers: tejohnson
Subscribers: llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D23537
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278776 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Fixed a bug in ThinLTOCodeGenerator's temp file dumping. The Twine
needs to be passed directly as an argument, or a copy saved into a
std::string.
It doesn't seem there are any consumers of this, so I added a new option
to llvm-lto to enable saving of temp files during ThinLTO, and augmented
a test to use it to check post-import but pre-opt bitcode.
Reviewers: mehdi_amini
Subscribers: llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D23525
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278761 91177308-0d34-0410-b5e6-96231b3b80d8
We currently do not touch a symbol's linkage in the case where a definition
has a single copy. However, this code is effectively unnecessary: either
the definition is not exported, in which case the internalize phase sets
its linkage to internal, or it is exported, in which case we need to promote
linkage to weak. Those two cases are already handled by existing code.
I believe that the only real functional change here is in the case where we
have a single definition which does not prevail (e.g. because the definition
in a native object file prevails). In that case we now lower linkage to
available_externally following the existing code path for that case.
As a result we can remove the isExported function parameter from the
thinLTOResolveWeakForLinkerInIndex function.
Differential Revision: http://reviews.llvm.org/D21883
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* UpdateCompilerUsed() -> updateCompilerUsed()
* ThinLTO doesn't use the API so we can remove the include
* Clean up unused #include <functional> from the header
* Rename #ifdef guard comment to be correct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@273461 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270698 91177308-0d34-0410-b5e6-96231b3b80d8
