Summary:
To enable profile-guided indirect call promotion in ThinLTO mode, we
simply add call graph edges for each profitable target from the profile
to the summaries, then the summary-guided importing will consider the
callee for importing as usual.
Also we need to enable the indirect call promotion pass creation in the
PassManagerBuilder when PerformThinLTO=true (we are in the ThinLTO
backend), so that the newly imported functions are considered for
promotion in the backends.
The IC promotion profiles refer to callees by GUID, which required
adding GUIDs to the per-module VST in bitcode (and assigning them
valueIds similar to how they are assigned valueIds in the combined
index).
Reviewers: mehdi_amini, xur
Subscribers: mehdi_amini, davidxl, llvm-commits
Differential Revision: http://reviews.llvm.org/D21932
llvm-svn: 275707
The linker supports a feature to force load an object from a static
archive if it defines an Objective-C category.
This API supports this feature by looking at every section in the
module to find if a category is defined in the module.
llvm-svn: 275125
I have an LTO snapshot (for which I don't have sources) that can't
be read back by LLVM. It seems the writer emitted broken bitcode
and this assertions aims at catching such cases.
llvm-svn: 274819
Summary:
This complements the earlier addition of IntrWriteMem and IntrWriteArgMem
LLVM intrinsic properties, see D18291.
Also start using the attribute for memset, memcpy, and memmove intrinsics,
and remove their special-casing in BasicAliasAnalysis.
Reviewers: reames, joker.eph
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D18714
llvm-svn: 274485
Summary:
This represents the adjustment applied to the implicit 'this' parameter
in the prologue of a virtual method in the MS C++ ABI. The adjustment is
always zero unless multiple inheritance is involved.
This increases the size of DISubprogram by 8 bytes, unfortunately. The
adjustment really is a signed 32-bit integer. If this size increase is
too much, we could probably win it back by splitting out a subclass with
info specific to virtual methods (virtuality, vindex, thisadjustment,
containingType).
Reviewers: aprantl, dexonsmith
Subscribers: aaboud, amccarth, llvm-commits
Differential Revision: http://reviews.llvm.org/D21614
llvm-svn: 274325
The function name Module::empty() is slightly misleading in that it
only tests for the presence of functions in the module. However we
still want to emit the module summary if the module contains only
global variables or aliases. The presence of such entities can be
determined simply by checking the summary directly, as we are doing
below.
Differential Revision: http://reviews.llvm.org/D21669
llvm-svn: 273638
This change is motivated by an upcoming change to the metadata representation
used for CFI. The indirect function call checker needs type information for
external function declarations in order to correctly generate jump table
entries for such declarations. We currently associate such type information
with declarations using a global metadata node, but I plan [1] to move all
such metadata to global object attachments.
In bitcode, metadata attachments for function declarations appear in the
global metadata block. This seems reasonable to me because I expect metadata
attachments on declarations to be uncommon. In the long term I'd also expect
this to be the case for CFI, because we'd want to use some specialized bitcode
format for this metadata that could be read as part of the ThinLTO thin-link
phase, which would mean that it would not appear in the global metadata block.
To solve the lazy loaded metadata issue I was seeing with D20147, I use the
same bitcode representation for metadata attachments for global variables as I
do for function declarations. Since there's a use case for metadata attachments
in the global metadata block, we might as well use that representation for
global variables as well, at least until we have a mechanism for lazy loading
global variables.
In the assembly format, the metadata attachments appear after the "declare"
keyword in order to avoid a parsing ambiguity.
[1] http://lists.llvm.org/pipermail/llvm-dev/2016-June/100462.html
Differential Revision: http://reviews.llvm.org/D21052
llvm-svn: 273336
pass manager passes' `run` methods.
This removes a bunch of SFINAE goop from the pass manager and just
requires pass authors to accept `AnalysisManager<IRUnitT> &` as a dead
argument. This is a small price to pay for the simplicity of the system
as a whole, despite the noise that changing it causes at this stage.
This will also helpfull allow us to make the signature of the run
methods much more flexible for different kinds af passes to support
things like intelligently updating the pass's progression over IR units.
While this touches many, many, files, the changes are really boring.
Mostly made with the help of my trusty perl one liners.
Thanks to Sean and Hal for bouncing ideas for this with me in IRC.
llvm-svn: 272978
If a local_unnamed_addr attribute is attached to a global, the address
is known to be insignificant within the module. It is distinct from the
existing unnamed_addr attribute in that it only describes a local property
of the module rather than a global property of the symbol.
This attribute is intended to be used by the code generator and LTO to allow
the linker to decide whether the global needs to be in the symbol table. It is
possible to exclude a global from the symbol table if three things are true:
- This attribute is present on every instance of the global (which means that
the normal rule that the global must have a unique address can be broken without
being observable by the program by performing comparisons against the global's
address)
- The global has linkonce_odr linkage (which means that each linkage unit must have
its own copy of the global if it requires one, and the copy in each linkage unit
must be the same)
- It is a constant or a function (which means that the program cannot observe that
the unique-address rule has been broken by writing to the global)
Although this attribute could in principle be computed from the module
contents, LTO clients (i.e. linkers) will normally need to be able to compute
this property as part of symbol resolution, and it would be inefficient to
materialize every module just to compute it.
See:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160509/356401.htmlhttp://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20160516/356738.html
for earlier discussion.
Part of the fix for PR27553.
Differential Revision: http://reviews.llvm.org/D20348
llvm-svn: 272709
r267296 used std::piecewise_construct without using
std::forward_as_tuple, and r267298 hacked it out (using an emplace_back
followed by a couple of reset() calls) because of a problem on a bot.
I'm finally circling back to call forward_as_tuple as I should have to
begin with (thanks to David Blaikie for pointing out the missing piece).
Note that this code uses emplace_back() instead of
push_back(make_pair()) because the move constructor for TrackingMDRef is
expensive (cheaper than a copy, but still expensive).
llvm-svn: 272306
Summary:
Now DISubroutineType has a 'cc' field which should be a DW_CC_ enum. If
it is present and non-zero, the backend will emit it as a
DW_AT_calling_convention attribute. On the CodeView side, we translate
it to the appropriate enum for the LF_PROCEDURE record.
I added a new LLVM vendor specific enum to the list of DWARF calling
conventions. DWARF does not appear to attempt to standardize these, so I
assume it's OK to do this until we coordinate with GCC on how to emit
vectorcall convention functions.
Reviewers: dexonsmith, majnemer, aaboud, amccarth
Subscribers: mehdi_amini, llvm-commits
Differential Revision: http://reviews.llvm.org/D21114
llvm-svn: 272197
This will be necessary to allow the global merge pass to attach
multiple debug info metadata nodes to global variables once we reverse
the edge from DIGlobalVariable to GlobalVariable.
Differential Revision: http://reviews.llvm.org/D20414
llvm-svn: 271358
This patch adds an IR, assembly and bitcode representation for metadata
attachments for globals. Future patches will port existing features to use
these new attachments.
Differential Revision: http://reviews.llvm.org/D20074
llvm-svn: 271348
When we have "Image Info Version" module flag but don't have "Class Properties"
module flag, set "Class Properties" module flag to 0, so we can correctly emit
errors when one module has the flag set and another module does not.
rdar://26469641
llvm-svn: 270791
Calls are initialized from a DenseMap. We can sort them using the
value id to recover some determinism during serialization.
From: mehdi_amini <mehdi_amini@91177308-0d34-0410-b5e6-96231b3b80d8>
llvm-svn: 269638
GlobalVars Refs are initialized from a DenseSet. We can sort them
using the value id to recover some determinism during serialization.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 269635
Calls are initialized from a DenseMap. We can sort them using the
value id to recover some determinism during serialization.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 269634
Refs are initialized from a DenseSet. We can sort them using the
value id to recover some determinism during serialization.
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 269629
This fixes a debug assert on Windows from the new iterator
implementation added in r269059. The Windows std::vector iterator
operator== checks in debug mode that the containers being iterated over
are the same, which they may not be.
Fixed by checking that we are iterating over the same container before
comparing the container iterators.
llvm-svn: 269232
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
The bitcode upgrade I added for DISubprogram in r266446 was based on the
assumption that the CU node for the subprogram was already materialized by the
time the DISubprogram is visited. This assumption may not hold true as future
versions of LLVM may decide to write out bitcode in a different order. This
patch corrects this by introducing a versioning bit next to the distinct flag to
unambiguously differentiate the new from the old record layouts.
Note for people stabilizing LLVM out-of-tree: This patch introduces a bitcode
incompatibility with llvm trunk revisions from r266446 — this commit. (But
D19987 will ensure that it degrades gracefully).
http://reviews.llvm.org/D20004
rdar://problem/26074194
llvm-svn: 268816
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
Summary:
With the removal of support for lazy parsing of combined index summary
records (e.g. r267344), we no longer need to include the summary record
bitcode offset in the VST entries for definitions. Change the combined
index format to be similar to the per-module index format in using value
ids to cross-reference from the summary record to the VST entry (rather
than the summary record bitcode offset to cross-reference in the other
direction).
The visible changes are:
1) Add the value id to the combined summary records
2) Remove the summary offset from the combined VST records, which has
the following effects:
- No longer need the VST_CODE_COMBINED_GVDEFENTRY record, as all
combined index VST entries now only contain the value id and
corresponding GUID.
- No longer have duplicate VST entries in the case where there are
multiple definitions of a symbol (e.g. weak/linkonce), as they all
have the same value id and GUID.
An implication of #2 above is that in order to hook up an alias to the
correct aliasee based on the value id of the aliasee recorded in the
combined index alias record, we need to scan the entries in the index
for that GUID to find the one from the same module (i.e. the case where
there are multiple entries for the aliasee). But the reader no longer
has to maintain a special map to hook up the alias/aliasee.
Reviewers: joker.eph
Subscribers: joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D19481
llvm-svn: 267712
There's hardly any functionality change here. Instead of calling
materializeMetadata on the first call to materialize(GlobalValue*), wait
until the first one that's actually going to do something. Noticed by
inspection; I don't have a concrete case where this makes a difference.
Added an assertion in materializeMetadata to be sure this (or a future
change) doesn't delay materializeMetadata after function-level metadata.
llvm-svn: 267345
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
Add tests for some missing cases to bitcode upgrade in r267296.
- DICompositeType with an 'elements:' field, which will cause it to be
involved in a cycle after the upgrade.
- A DIDerivedType that references a class in 'extraData:'.
I updated test/Bitcode/dityperefs-3.8.ll with the missing cases and
regenerated test/Bitcode/dityperefs-3.8.ll.bc.
llvm-svn: 267332
Right now it only contains the LinkageType, but will be extended
with "hasSection", "isOptSize", "hasInlineAssembly", etc.
Differential Revision: http://reviews.llvm.org/D19404
From: Mehdi Amini <mehdi.amini@apple.com>
llvm-svn: 267319
Teresa Johnson