This is exciting as this is a much more involved port. This is
a complex, existing transformation pass. All of the core logic is shared
between both old and new pass managers. Only the access to the analyses
is separate because the actual techniques are separate. This also uses
a bunch of different and interesting analyses and is the first time
where we need to use an analysis across an IR layer.
This also paves the way to expose instcombine utility functions. I've
got a static function that implements the core pass logic over
a function which might be mildly interesting, but more interesting is
likely exposing a routine which just uses instructions *already in* the
worklist and combines until empty.
I've switched one of my favorite instcombine tests to run with both as
well to make sure this keeps working.
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manager to support the actual uses of it. =]
When I ported instcombine to the new pass manager I discover that it
didn't work because TLI wasn't available in the right places. This is
a somewhat surprising and/or subtle aspect of the new pass manager
design that came up before but I think is useful to be reminded of:
While the new pass manager *allows* a function pass to query a module
analysis, it requires that the module analysis is already run and cached
prior to the function pass manager starting up, possibly with
a 'require<foo>' style utility in the pass pipeline. This is an
intentional hurdle because using a module analysis from a function pass
*requires* that the module analysis is run prior to entering the
function pass manager. Otherwise the other functions in the module could
be in who-knows-what state, etc.
A somewhat surprising consequence of this design decision (at least to
me) is that you have to design a function pass that leverages
a module analysis to do so as an optional feature. Even if that means
your function pass does no work in the absence of the module analysis,
you have to handle that possibility and remain conservatively correct.
This is a natural consequence of things being able to invalidate the
module analysis and us being unable to re-run it. And it's a generally
good thing because it lets us reorder passes arbitrarily without
breaking correctness, etc.
This ends up causing problems in one case. What if we have a module
analysis that is *definitionally* impossible to invalidate. In the
places this might come up, the analysis is usually also definitionally
trivial to run even while other transformation passes run on the module,
regardless of the state of anything. And so, it follows that it is
natural to have a hard requirement on such analyses from a function
pass.
It turns out, that TargetLibraryInfo is just such an analysis, and
InstCombine has a hard requirement on it.
The approach I've taken here is to produce an analysis that models this
flexibility by making it both a module and a function analysis. This
exposes the fact that it is in fact safe to compute at any point. We can
even make it a valid CGSCC analysis at some point if that is useful.
However, we don't want to have a copy of the actual target library info
state for each function! This state is specific to the triple. The
somewhat direct and blunt approach here is to turn TLI into a pimpl,
with the state and mutators in the implementation class and the query
routines primarily in the wrapper. Then the analysis can lazily
construct and cache the implementations, keyed on the triple, and
on-demand produce wrappers of them for each function.
One minor annoyance is that we will end up with a wrapper for each
function in the module. While this is a bit wasteful (one pointer per
function) it seems tolerable. And it has the advantage of ensuring that
we pay the absolute minimum synchronization cost to access this
information should we end up with a nice parallel function pass manager
in the future. We could look into trying to mark when analysis results
are especially cheap to recompute and more eagerly GC-ing the cached
results, or we could look at supporting a variant of analyses whose
results are specifically *not* cached and expected to just be used and
discarded by the consumer. Either way, these seem like incremental
enhancements that should happen when we start profiling the memory and
CPU usage of the new pass manager and not before.
The other minor annoyance is that if we end up using the TLI in both
a module pass and a function pass, those will be produced by two
separate analyses, and thus will point to separate copies of the
implementation state. While a minor issue, I dislike this and would like
to find a way to cleanly allow a single analysis instance to be used
across multiple IR unit managers. But I don't have a good solution to
this today, and I don't want to hold up all of the work waiting to come
up with one. This too seems like a reasonable thing to incrementally
improve later.
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This patch adds a new set of JIT APIs to LLVM. The aim of these new APIs is to
cleanly support a wider range of JIT use cases in LLVM, and encourage the
development and contribution of re-usable infrastructure for LLVM JIT use-cases.
These APIs are intended to live alongside the MCJIT APIs, and should not affect
existing clients.
Included in this patch:
1) New headers in include/llvm/ExecutionEngine/Orc that provide a set of
components for building JIT infrastructure.
Implementation code for these headers lives in lib/ExecutionEngine/Orc.
2) A prototype re-implementation of MCJIT (OrcMCJITReplacement) built out of the
new components.
3) Minor changes to RTDyldMemoryManager needed to support the new components.
These changes should not impact existing clients.
4) A new flag for lli, -use-orcmcjit, which will cause lli to use the
OrcMCJITReplacement class as its underlying execution engine, rather than
MCJIT itself.
Tests to follow shortly.
Special thanks to Michael Ilseman, Pete Cooper, David Blaikie, Eric Christopher,
Justin Bogner, and Jim Grosbach for extensive feedback and discussion.
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I had already factored this analysis specifically to enable doing this,
but hadn't actually committed the necessary wiring to get at this from
the new pass manager. This also nicely shows how the separate cache
object can be directly managed by the new pass manager.
This analysis didn't have any direct tests and so I've added a printer
pass and a boring test case. I chose to print the i1 value which is
being assumed rather than the call to llvm.assume as that seems much
more useful for testing... but suggestions on an even better printing
strategy welcome. My main goal was to make sure things actually work. =]
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Summary:
The default copy and assignment operators for these objects probably don't actually do what the clients intend, so they should be deleted.
Places using the assignment operator to set the value of an option should cast to the option's data type first to call into the override for operator=. Places using the copy constructor just need to be changed to not copy (i.e. passing by const reference instead of value).
Reviewers: dexonsmith, chandlerc
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D7114
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pass and a LoopPrinterPass with the expected associated wiring.
I've added a RUN line to the only test case (!!!) we have that actually
prints loops. Everything seems to be working.
This is somewhat exciting as this is the first analysis using another
analysis to go in for the new pass manager. =D I also believe it is the
last analysis necessary for porting instcombine, but of course I may yet
discover more.
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It will be needed to instantiate the Target object that we will
use to create all the MC objects for the dwarf emission.
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Add an additional based relocation to the enumeration of based relocation names.
The lack of the enumerator value causes issues when inspecting WoA binaries.
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TargetLibraryAnalysis pass.
There are actually no direct tests of this already in the tree. I've
added the most basic test that the pass manager bits themselves work,
and the TLI object produced will be tested by an upcoming patches as
they port passes which rely on TLI.
This is starting to point out the awkwardness of the invalidate API --
it seems poorly fitting on the *result* object. I suspect I will change
it to live on the analysis instead, but that's not for this change, and
I'd rather have a few more passes ported in order to have more
experience with how this plays out.
I believe there is only one more analysis required in order to start
porting instcombine. =]
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The pass is really just a means of accessing a cached instance of the
TargetLibraryInfo object, and this way we can re-use that object for the
new pass manager as its result.
Lots of delta, but nothing interesting happening here. This is the
common pattern that is developing to allow analyses to live in both the
old and new pass manager -- a wrapper pass in the old pass manager
emulates the separation intrinsic to the new pass manager between the
result and pass for analyses.
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While the term "Target" is in the name, it doesn't really have to do
with the LLVM Target library -- this isn't an abstraction which LLVM
targets generally need to implement or extend. It has much more to do
with modeling the various runtime libraries on different OSes and with
different runtime environments. The "target" in this sense is the more
general sense of a target of cross compilation.
This is in preparation for porting this analysis to the new pass
manager.
No functionality changed, and updates inbound for Clang and Polly.
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This can happen if:
* It is present in a comdat in one file.
* It is not present in the comdat of the file that is kept.
* Is is not used.
This should fix the LTO boostrap.
Thanks to Takumi NAKAMURA for setting up the bot!
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utils/sort_includes.py.
I clearly haven't done this in a while, so more changed than usual. This
even uncovered a missing include from the InstrProf library that I've
added. No functionality changed here, just mechanical cleanup of the
include order.
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This adds the domtree analysis to the new pass manager. The analysis
returns the same DominatorTree result entity used by the old pass
manager and essentially all of the code is shared. We just have
different boilerplate for running and printing the analysis.
I've converted one test to run in both modes just to make sure this is
exercised while both are live in the tree.
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and expose the necessary hooks in the API directly.
This makes it much cleaner for example to log the usage of a pass
manager from a library. It also makes it more obvious that this
functionality isn't "optional" or "asserts-only" for the pass manager.
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template.
This consolidates three copies of nearly the same core logic. It adds
"complexity" to the ModuleAnalysisManager in that it makes it possible
to share a ModuleAnalysisManager across multiple modules... But it does
so by deleting *all of the code*, so I'm OK with that. This will
naturally make fixing bugs in this code much simpler, etc.
The only down side here is that we have to use 'typename' and 'this->'
in various places, and the implementation is lifted into the header.
I'll take that for the code size reduction.
The convenient names are still typedef-ed and used throughout so that
users can largely ignore this aspect of the implementation.
The follow-up change to this will do the exact same refactoring for the
PassManagers. =D
It turns out that the interesting different code is almost entirely in
the adaptors. At the end, that should be essentially all that is left.
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The bitcode reading interface used std::error_code to report an error to the
callers and it is the callers job to print diagnostics.
This is not ideal for error handling or diagnostic reporting:
* For error handling, all that the callers care about is 3 possibilities:
* It worked
* The bitcode file is corrupted/invalid.
* The file is not bitcode at all.
* For diagnostic, it is user friendly to include far more information
about the invalid case so the user can find out what is wrong with the
bitcode file. This comes up, for example, when a developer introduces a
bug while extending the format.
The compromise we had was to have a lot of error codes.
With this patch we use the DiagnosticHandler to communicate with the
human and std::error_code to communicate with the caller.
This allows us to have far fewer error codes and adds the infrastructure to
print better diagnostics. This is so because the diagnostics are printed when
he issue is found. The code that detected the problem in alive in the stack and
can pass down as much context as needed. As an example the patch updates
test/Bitcode/invalid.ll.
Using a DiagnosticHandler also moves the fatal/non-fatal error decision to the
caller. A simple one like llvm-dis can just use fatal errors. The gold plugin
needs a bit more complex treatment because of being passed non-bitcode files. An
hypothetical interactive tool would make all bitcode errors non-fatal.
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This reverts commit r225498 (but leaves r225499, which was a worthy
cleanup).
My plan was to change `DEBUG_LOC` to store the `MDNode` directly rather
than its operands (patch was to go out this morning), but on reflection
it's not clear that it's strictly better. (I had missed that the
current code is unlikely to emit the `MDNode` at all.)
Conflicts:
lib/Bitcode/Reader/BitcodeReader.cpp (due to r225499)
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options other than just -disassemble so that universal files can be used with other
options combined with -arch options.
No functional change to existing options and use. One test case added for the
additional functionality with a universal file an a -arch option.
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requiring and invalidating specific analyses. Also make their printed
names match their class names. Writing these out as prose really doesn't
make sense to me any more.
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Use this to test that path of invalidation. This test actually shows
redundant invalidation here that is really bad. I'm going to work on
fixing that next, but wanted to commit the test harness now that its all
working.
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remove an extra, redundant pass manager wrapping every run.
I had kept seeing these when manually testing, but it was getting really
annoying and was going to cause problems with overly eager invalidation.
The root cause was an overly complex and unnecessary pile of code for
parsing the outer layer of the pass pipeline. We can instead delegate
most of this to the recursive pipeline parsing.
I've added some somewhat more basic and precise tests to catch this.
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a specific analysis result.
This is quite handy to test things, and will also likely be very useful
for debugging issues. You could narrow down pass validation failures by
walking these invalidate pass runs up and down the pass pipeline, etc.
I've added support to the pass pipeline parsing to be able to create one
of these for any analysis pass desired.
Just adding this class uncovered one latent bug where the
AnalysisManager CRTP base class had a hard-coded Module type rather than
using IRUnitT.
I've also added tests for invalidation and caching of analyses in
a basic way across all the pass managers. These in turn uncovered two
more bugs where we failed to correctly invalidate an analysis -- its
results were invalidated but the key for re-running the pass was never
cleared and so it was never re-run. Quite nasty. I'm very glad to debug
this here rather than with a full system.
Also, yes, the naming here is horrid. I'm going to update some of the
names to be slightly less awful shortly. But really, I've no "good"
ideas for naming. I'll be satisfied if I can get it to "not bad".
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more verbose than I'd like, but the code really isn't that interesting,
and this still seems vastly simpler than any other solutions I've come
up with. =] Maybe if we get to the 10th IR unit, this will be a problem
in practice.
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manager tests to use them and be significantly more comprehensive.
This, naturally, uncovered a bug where the CGSCC pass manager wasn't
printing analyses when they were run.
The only remaining core manipulator is I think an invalidate pass
similar to the require pass. That'll be next. =]
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simplify things. This will become more important as I add no-op analyses
that want to re-use the logic we already have for analyses in the
registry. For now, no functionality changed.
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a normal interface for it in Passes.h.
This gives us essentially a single interface for running pass managers
which are provided from the bottom of the LLVM stack through interfaces
at the top of the LLVM stack that populate them with all of the
different analyses available throughout. It also means there is a single
blob of code that needs to include all of the pass headers and needs to
deal with the registry of passes and parsing names.
No functionality changed intended, should just be cleanup.
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is a no-op other than requiring some analysis results be available.
This can be used in real pass pipelines to force the usually lazy
analysis running to eagerly compute something at a specific point, and
it can be used to test the pass manager infrastructure (my primary use
at the moment).
I've also added bit of pipeline parsing magic to support generating
these directly from the opt command so that you can directly use these
when debugging your analysis. The syntax is:
require<analysis-name>
This can be used at any level of the pass manager. For example:
cgscc(function(require<my-analysis>,no-op-function))
This would produce a no-op function pass requiring my-analysis, followed
by a fully no-op function pass, both of these in a function pass manager
which is nested inside of a bottom-up CGSCC pass manager which is in the
top-level (implicit) module pass manager.
I have zero attachment to the particular syntax I'm using here. Consider
it a straw man for use while I'm testing and fleshing things out.
Suggestions for better syntax welcome, and I'll update everything based
on any consensus that develops.
I've used this new functionality to more directly test the analysis
printing rather than relying on the cgscc pass manager running an
analysis for me. This is still minimally tested because I need to have
analyses to run first! ;] That patch is next, but wanted to keep this
one separate for easier review and discussion.
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This object is meant to own the ObjectFiles and their underlying
MemoryBuffer. It is basically the equivalent of an OwningBinary
except that it efficiently handles Archives. It is optimized for
efficiently providing mappings of members of the same archive when
they are opened successively (which is standard in Darwin debug
maps, objects from the same archive will be contiguous).
Of course, the BinaryHolder will also be used by the DWARF linker
once it is commited, but for now only the debug map parser uses it.
With this change, you can run llvm-dsymutil on your Darwin debug build
of clang and get a complete debug map for it.
Differential Revision: http://reviews.llvm.org/D6690
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units.
This was debated back and forth a bunch, but using references is now
clearly cleaner. Of all the code written using pointers thus far, in
only one place did it really make more sense to have a pointer. In most
cases, this just removes immediate dereferencing from the code. I think
it is much better to get errors on null IR units earlier, potentially
at compile time, than to delay it.
Most notably, the legacy pass manager uses references for its routines
and so as more and more code works with both, the use of pointers was
likely to become really annoying. I noticed this when I ported the
domtree analysis over and wrote the entire thing with references only to
have it fail to compile. =/ It seemed better to switch now than to
delay. We can, of course, revisit this is we learn that references are
really problematic in the API.
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The required functionality has been there for some time, but I never
managed to actually wire it into the command line registry of passes.
Let's do that.
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This enhances llvm-readobj to print out the COFF export table, similar to the
-coff-import option. This is useful for testing in lld.
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For this to work, we have to encode it in the build variables and use it
from llvm-config.cpp. I've tried to do this reasonably cleanly, but the
code for llvm-config.cpp is pretty strange. However, with this,
llvm-config stops giving the wrong answer when using LLVM_LIBDIR_SUFFIX.
Note that the configure+make build just sets this to an empty string as
that build system has zero support for multilib of any form. I'm not
planning to add support there either, but this should leave a path for
anyone that wanted to.
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*numerous* places where it was missing in the CMake build. The primary
change here is that the suffix is now actually used for all of the lib
directories in the LLVM project's CMake. The various subprojects still
need similar treatment.
This is the first of a series of commits to try to make LLVM's cmake
effective in a multilib Linux installation. I don't think many people
are seriously using this variable so I'm hoping the fallout will be
minimal. A somewhat unfortunate consequence of the nature of these
commits is that until I land all of them, they will in part make the
brokenness of our multilib support more apparant. At the end, things
should actually work.
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Export symbols in libLTO.dylib for the local context-related functions
added in r221733 (`LTO_API_VERSION=11`)... and add the missing
definition for `lto_codegen_create_in_local_context()`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224567 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: We should only have llvm-c-test use libLLVM if the library is built with the default set of components or if LLVM_DYLIB_COMPONENTS includes all the LLVM_LINK_COMPONENTS required for llvm-c-test. Making libLLVM always used causes build failures if libLLVM doesn't include all
Reviewers: chapuni, ributzka
Reviewed By: ributzka
Subscribers: ributzka, llvm-commits
Differential Revision: http://reviews.llvm.org/D6668
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Also corrected the name of the load command to not end in an ’S’ as well as corrected
the name of the MachO::linker_option_command struct and other places that had the
word option as plural which did not match the Mac OS X headers.
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Add coverage in `llvm-lto` for the API exposed by libLTO to create
modules in local contexts.
The goal here isn't to test the symbol-related API extensively, just to
confirm that these modules work at all. (I'll be shifting code around
soon that should be NFC and I realized there was no test coverage.)
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The line mapping information for dynamic code is reported incorrectly. It causes VTune to map LLVM generated code to source lines incorrectly. This patch fix this issue.
Patch by Denis Pravdin.
Differential Revision: http://reviews.llvm.org/D6603
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The goal of this tool is to replicate Darwin's dsymutil functionality
based on LLVM. dsymutil is a DWARF linker. Darwin's linker (ld64) does
not link the debug information, it leaves it in the object files in
relocatable form, but embbeds a `debug map` into the executable that
describes where to find the debug information and how to relocate it.
When releasing/archiving a binary, dsymutil is called to link all the DWARF
information into a `dsym bundle` that can distributed/stored along with
the binary.
With this commit, the LLVM based dsymutil is just able to parse the STABS
debug maps embedded by ld64 in linked binaries (and not all of them, for
example archives aren't supported yet).
Note that the tool directory is called dsymutil, but the executable is
currently called llvm-dsymutil. This discrepancy will disappear once the
tool will be feature complete. At this point the executable will be renamed
to dsymutil, but until then you do not want it to override the system one.
Differential Revision: http://reviews.llvm.org/D6242
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In release builds this is actually possible as without asserts there is
no testing of the actual read bytes and the variables could be partially
uninitialized.
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This reflects the typelessness of `Metadata` in the bitcode format,
removing types from all metadata operands.
`METADATA_VALUE` represents a `ValueAsMetadata`, and always has two
fields: the type and the value.
`METADATA_NODE` represents an `MDNode`, and unlike `METADATA_OLD_NODE`,
doesn't store types. It stores operands at their ID+1 so that `0` can
reference `nullptr` operands.
Part of PR21532.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224073 91177308-0d34-0410-b5e6-96231b3b80d8
This cuts down the number on system calls done by a static llvm-ar producing
lib/libclangSema.a from 9164 to 442.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@224025 91177308-0d34-0410-b5e6-96231b3b80d8
The complicated situation is when we have to keep an alias but drop a GV
that is part of the aliasee.
We used to clone the dropped GV and make the clone internal. This is wasteful
as we know the original will be dropped.
With this patch what is done instead is set the linkage of the original to
internal and replace all uses (but the one in the alias) with a new
declaration that takes the name of the old GV. This saves us from having
to copy the body.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@223863 91177308-0d34-0410-b5e6-96231b3b80d8
