The current demand propagator for addition will mark all input bits at and right of the alive output bit as alive. But carry won't propagate beyond a bit for which both operands are zero (or one/zero in the case of subtraction) so a more accurate answer is possible given known bits.
I derived a propagator by working through truth tables and using a bit-reversed addition to make demand ripple to the right, but I'm not sure how to make a convincing argument for its correctness in the comments yet. Nevertheless, here's a minimal implementation and test to get feedback.
This would help in a situation where, for example, four bytes (<128) packed into an int are added with four others SIMD-style but only one of the four results is actually read.
Known A: 0_______0_______0_______0_______
Known B: 0_______0_______0_______0_______
AOut: 00000000001000000000000000000000
AB, current: 00000000001111111111111111111111
AB, patch: 00000000001111111000000000000000
Committed on behalf of: @rrika (Erika)
Differential Revision: https://reviews.llvm.org/D72423
Summary:
Splitting Knowledge retention into Queries in Analysis and Builder into Transform/Utils
allows Queries and Transform/Utils to use Analysis.
Reviewers: jdoerfert, sstefan1
Reviewed By: jdoerfert
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D77171
Summary:
Assume bundles need to be usable by Analysis and Transforms/Utils isn't.
so this commit moves utilities to deal with asusme bundles to IR.
Reviewers: jdoerfert
Reviewed By: jdoerfert
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D75618
The CallGraphUpdater is a helper that simplifies the process of updating
the call graph, both old and new style, while running an CGSCC pass.
The uses are contained in different commits, e.g. D70767.
More functionality is added as we need it.
Reviewed By: modocache, hfinkel
Differential Revision: https://reviews.llvm.org/D70927
Reintroduces the scalable vector IR type from D32530, after it was reverted
a couple of times due to increasing chromium LTO build times. This latest
incarnation removes the walk over aggregate types from the verifier entirely,
in favor of rejecting scalable vectors in the isValidElementType methods in
ArrayType and StructType. This removes the 70% degradation observed with
the second repro tarball from PR42210.
Reviewers: thakis, hans, rengolin, sdesmalen
Reviewed By: sdesmalen
Differential Revision: https://reviews.llvm.org/D64079
llvm-svn: 365203
We saw a 70% ThinLTO link time increase in Chromium for Android, see
crbug.com/978817. Sounds like more of PR42210.
> Recommit of D32530 with a few small changes:
> - Stopped recursively walking through aggregates in
> the verifier, so that we don't impose too much
> overhead on large modules under LTO (see PR42210).
> - Changed tests to match; the errors are slightly
> different since they only report the array or
> struct that actually contains a scalable vector,
> rather than all aggregates which contain one in
> a nested member.
> - Corrected an older comment
>
> Reviewers: thakis, rengolin, sdesmalen
>
> Reviewed By: sdesmalen
>
> Differential Revision: https://reviews.llvm.org/D63321
llvm-svn: 364543
Recommit of D32530 with a few small changes:
- Stopped recursively walking through aggregates in
the verifier, so that we don't impose too much
overhead on large modules under LTO (see PR42210).
- Changed tests to match; the errors are slightly
different since they only report the array or
struct that actually contains a scalable vector,
rather than all aggregates which contain one in
a nested member.
- Corrected an older comment
Reviewers: thakis, rengolin, sdesmalen
Reviewed By: sdesmalen
Differential Revision: https://reviews.llvm.org/D63321
llvm-svn: 363658
* Adds a 'scalable' flag to VectorType
* Adds an 'ElementCount' class to VectorType to pass (possibly scalable) vector lengths, with overloaded operators.
* Modifies existing helper functions to use ElementCount
* Adds support for serializing/deserializing to/from both textual and bitcode IR formats
* Extends the verifier to reject global variables of scalable types
* Updates documentation
See the latest version of the RFC here: http://lists.llvm.org/pipermail/llvm-dev/2018-July/124396.html
Reviewers: rengolin, lattner, echristo, chandlerc, hfinkel, rkruppe, samparker, SjoerdMeijer, greened, sebpop
Reviewed By: hfinkel, sebpop
Differential Revision: https://reviews.llvm.org/D32530
llvm-svn: 361953
TimePassesHandler object (implementation of time-passes for new pass manager)
gains ability to report into a stream customizable per-instance (per pipeline).
Intended use is to specify separate time-passes output stream per each compilation,
setting up TimePasses member of StandardInstrumentation during PassBuilder setup.
That allows to get independent non-overlapping pass-times reports for parallel
independent compilations (in JIT-like setups).
By default it still puts timing reports into the info-output-file stream
(created by CreateInfoOutputFile every time report is requested).
Unit-test added for non-default case, and it also allowed to discover that print() does not work
as declared - it did not reset the timers, leading to yet another report being printed into the default stream.
Fixed print() to actually reset timers according to what was declared in print's comments before.
Reviewed By: philip.pfaffe
Differential Revision: https://reviews.llvm.org/D59366
llvm-svn: 356305
Use this feature to fix a bug on ARM where 4 byte alignment is
incorrectly assumed.
Differential Revision: https://reviews.llvm.org/D57335
llvm-svn: 355685
Use this feature to fix a bug on ARM where 4 byte alignment is
incorrectly assumed.
Differential Revision: https://reviews.llvm.org/D57335
llvm-svn: 355585
Use this feature to fix a bug on ARM where 4 byte alignment is
incorrectly assumed.
Differential Revision: https://reviews.llvm.org/D57335
llvm-svn: 355522
DomTreeUpdater depends on headers from Analysis, but is in IR. This is a
layering violation since Analysis depends on IR. Relocate this code from IR
to Analysis to fix the layering violation.
llvm-svn: 353265
This shortcut mechanism for creating types was added 10 years ago, but
has seen almost no uptake since then, neither internally nor in
external projects.
The very small number of characters saved by using it does not seem
worth the mental overhead of an additional type-creation API, so,
delete it.
Differential Revision: https://reviews.llvm.org/D56573
llvm-svn: 351020
All the PassBuilder::parse interfaces now return descriptive StringError
instead of a plain bool. It allows to make -passes/aa-pipeline parsing
errors context-specific and thus less confusing.
TODO: ideally we should also make suggestions for misspelled pass names,
but that requires some extensions to PassBuilder.
Reviewed By: philip.pfaffe, chandlerc
Differential Revision: https://reviews.llvm.org/D53246
llvm-svn: 344685
Summary:
All the PassBuilder::parse interfaces now return descriptive StringError
instead of a plain bool. It allows to make -passes/aa-pipeline parsing
errors context-specific and thus less confusing.
TODO: ideally we should also make suggestions for misspelled pass names,
but that requires some extensions to PassBuilder.
Reviewed By: philip.pfaffe, chandlerc
Differential Revision: https://reviews.llvm.org/D53246
llvm-svn: 344519
Summary: After converting all existing passes to use the new DomTreeUpdater interface, there isn't any usage of the original DeferredDominance class. Thus, we can safely remove it from the codebase.
Reviewers: kuhar, brzycki, dmgreen, davide, grosser
Reviewed By: kuhar, brzycki
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D49747
llvm-svn: 339502
Summary:
This patch is the first in a series of patches related to the [[ http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html | RFC - A new dominator tree updater for LLVM ]].
This patch introduces the DomTreeUpdater class, which provides a cleaner API to perform updates on available dominator trees (none, only DomTree, only PostDomTree, both) using different update strategies (eagerly or lazily) to simplify the updating process.
—Prior to the patch—
- Directly calling update functions of DominatorTree updates the data structure eagerly while DeferredDominance does updates lazily.
- DeferredDominance class cannot be used when a PostDominatorTree also needs to be updated.
- Functions receiving DT/DDT need to branch a lot which is currently necessary.
- Functions using both DomTree and PostDomTree need to call the update function separately on both trees.
- People need to construct an additional DeferredDominance class to use functions only receiving DDT.
—After the patch—
Patch by Chijun Sima <simachijun@gmail.com>.
Reviewers: kuhar, brzycki, dmgreen, grosser, davide
Reviewed By: kuhar, brzycki
Author: NutshellySima
Subscribers: vsk, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D48383
llvm-svn: 336163
Summary:
This patch is the first in a series of patches related to the [[ http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html | RFC - A new dominator tree updater for LLVM ]].
This patch introduces the DomTreeUpdater class, which provides a cleaner API to perform updates on available dominator trees (none, only DomTree, only PostDomTree, both) using different update strategies (eagerly or lazily) to simplify the updating process.
—Prior to the patch—
- Directly calling update functions of DominatorTree updates the data structure eagerly while DeferredDominance does updates lazily.
- DeferredDominance class cannot be used when a PostDominatorTree also needs to be updated.
- Functions receiving DT/DDT need to branch a lot which is currently necessary.
- Functions using both DomTree and PostDomTree need to call the update function separately on both trees.
- People need to construct an additional DeferredDominance class to use functions only receiving DDT.
—After the patch—
Patch by Chijun Sima <simachijun@gmail.com>.
Reviewers: kuhar, brzycki, dmgreen, grosser, davide
Reviewed By: kuhar, brzycki
Subscribers: vsk, mgorny, llvm-commits
Author: NutshellySima
Differential Revision: https://reviews.llvm.org/D48383
llvm-svn: 336114
Now the Windows mangling modes ('w' and 'x') do not do any mangling for
symbols starting with '?'. This means that clang can stop adding the
hideous '\01' leading escape. This means LLVM debug logs are less likely
to contain ASCII escape characters and it will be easier to copy and
paste MS symbol names from IR.
Finally.
For non-Windows platforms, names starting with '?' still get IR
mangling, so once clang stops escaping MS C++ names, we will get extra
'_' prefixing on MachO. That's fine, since it is currently impossible to
construct a triple that uses the MS C++ ABI in clang and emits macho
object files.
Differential Revision: https://reviews.llvm.org/D7775
llvm-svn: 327734
Summary:
See D37528 for a previous (non-deferred) version of this
patch and its description.
Preserves dominance in a deferred manner using a new class
DeferredDominance. This reduces the performance impact of
updating the DominatorTree at every edge insertion and
deletion. A user may call DDT->flush() within JumpThreading
for an up-to-date DT. This patch currently has one flush()
at the end of runImpl() to ensure DT is preserved across
the pass.
LVI is also preserved to help subsequent passes such as
CorrelatedValuePropagation. LVI is simpler to maintain and
is done immediately (not deferred). The code to perform the
preversation was minimally altered and simply marked as
preserved for the PassManager to be informed.
This extends the analysis available to JumpThreading for
future enhancements such as threading across loop headers.
Reviewers: dberlin, kuhar, sebpop
Reviewed By: kuhar, sebpop
Subscribers: mgorny, dmgreen, kuba, rnk, rsmith, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40146
llvm-svn: 322401
Summary:
This patch introduces a way of informing the (Post)DominatorTree about multiple CFG updates that happened since the last tree update. This makes performing tree updates much easier, as it internally takes care of applying the updates in lockstep with the (virtual) updates to the CFG, which is done by reverse-applying future CFG updates.
The batch updater is able to remove redundant updates that cancel each other out. In the future, it should be also possible to reorder updates to reduce the amount of work needed to perform the updates.
Reviewers: dberlin, sanjoy, grosser, davide, brzycki
Reviewed By: brzycki
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D36167
llvm-svn: 311015
Summary:
This patch introduces a new testing utility for building and modifying CFG -- CFGBuilder. The primary use case for the utility is testing the upcoming incremental dominator tree update API.
The current design provides a simple mechanism of constructing arbitrary graphs and then applying series of updates to them. CFGBuilder takes care of creating empty functions, connecting and disconnecting basic blocks. Under the hood it uses SwitchInst and UnreachableInst.
It will be also possible to create a thin wrapper over CFGBuilder for parsing string input and to hook it up to other textual tools (e.g. opt used with FileCheck).
Reviewers: dberlin, sanjoy, grosser, dblaikie
Reviewed By: dblaikie
Subscribers: davide, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D34798
llvm-svn: 307960
Summary:
This patch adds a callback registration API to the PassBuilder,
enabling registering out-of-tree passes with it.
Through the Callback API, callers may register callbacks with the
various stages at which passes are added into pass managers, including
parsing of a pass pipeline as well as at extension points within the
default -O pipelines.
Registering utilities like `require<>` and `invalidate<>` needs to be
handled manually by the caller, but a helper is provided.
Additionally, adding passes at pipeline extension points is exposed
through the opt tool. This patch adds a `-passes-ep-X` commandline
option for every extension point X, which opt parses into pipelines
inserted into that extension point.
Reviewers: chandlerc
Reviewed By: chandlerc
Subscribers: lksbhm, grosser, davide, mehdi_amini, llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D33464
llvm-svn: 307532
block.
This allows writing much more natural and readable range based for loops
directly over the PHI nodes. It also takes advantage of the same tricks
for terminating the sequence as the hand coded versions.
I've replaced one example of this mostly to showcase the difference and
I've added a unit test to make sure the facilities really work the way
they're intended. I want to use this inside of SimpleLoopUnswitch but it
seems generally nice.
Differential Revision: https://reviews.llvm.org/D33533
llvm-svn: 303964
Split out a new, low-level intrusive list type with clear semantics.
Unlike iplist (and ilist), all operations on simple_ilist are intrusive,
and simple_ilist never takes ownership of its nodes. This enables an
intuitive API that has the right defaults for intrusive lists.
- insert() takes references (not pointers!) to nodes (in iplist/ilist,
passing a reference will cause the node to be copied).
- erase() takes only iterators (like std::list), and does not destroy
the nodes.
- remove() takes only references and has the same behaviour as erase().
- clear() does not destroy the nodes.
- The destructor does not destroy the nodes.
- New API {erase,remove,clear}AndDispose() take an extra Disposer
functor for callsites that want to call some disposal routine (e.g.,
std::default_delete).
This list is not currently configurable, and has no callbacks.
The initial motivation was to fix iplist<>::sort to work correctly (even
with callbacks in ilist_traits<>). iplist<> uses simple_ilist<>::sort
directly. The new test in unittests/IR/ModuleTest.cpp crashes without
this commit.
Fixing sort() via a low-level layer provided a good opportunity to:
- Unit test the low-level functionality thoroughly.
- Modernize the API, largely inspired by other intrusive list
implementations.
Here's a sketch of a longer-term plan:
- Create BumpPtrList<>, a non-intrusive list implemented using
simple_ilist<>, and use it for the Token list in
lib/Support/YAMLParser.cpp. This will factor out the only real use of
createNode().
- Evolve the iplist<> and ilist<> APIs in the direction of
simple_ilist<>, making allocation/deallocation explicit at call sites
(similar to simple_ilist<>::eraseAndDispose()).
- Factor out remaining calls to createNode() and deleteNode() and remove
the customization from ilist_traits<>.
- Transition uses of iplist<>/ilist<> that don't need callbacks over to
simple_ilist<>.
llvm-svn: 280107
The second test in this file is actually testing DICompositeType API,
not LLVMContext API (after r266742 moved it to a higher level). This
really doesn't make sense in an LLVMContextTest. Rename the tests
before adding more.
llvm-svn: 266764
Rather than relying on the structural equivalence of DICompositeType to
merge type definitions, use an explicit map on the LLVMContext that
LLParser and BitcodeReader consult when constructing new nodes.
Each non-forward-declaration DICompositeType with a non-empty
'identifier:' field is stored/loaded from the type map, and the first
definiton will "win".
This map is opt-in: clients that expect ODR types from different modules
to be merged must call LLVMContext::ensureDITypeMap.
- Clients that just happen to load more than one Module in the same
LLVMContext won't magically merge types.
- Clients (like LTO) that want to continue to merge types based on ODR
identifiers should opt-in immediately.
I have updated LTOCodeGenerator.cpp, the two "linking" spots in
gold-plugin.cpp, and llvm-link (unless -disable-debug-info-type-map) to
set this.
With this in place, it will be straightforward to remove the DITypeRef
concept (i.e., referencing types by their 'identifier:' string rather
than pointing at them directly).
llvm-svn: 266549
Instead of copying arguments from the source function to the
destination, steal them. This has a few advantages.
- The ValueMap doesn't need to be seeded with (or cleared of)
Arguments.
- Often the destination function won't have created any arguments yet,
so this avoids malloc traffic.
- Argument names don't need to be copied.
Because argument lists are lazy, this required a new
Function::stealArgumentListFrom helper.
llvm-svn: 265519
Fix PR24852 (crash with -debug -instcombine)
Patch by Than McIntosh <thanm@google.com>
Summary:
Add guards to the asm writer to prevent crashing
when dumping an instruction that has no basic
block.
Differential Revision: http://reviews.llvm.org/D15798
From: Than McIntosh <thanm@google.com>
llvm-svn: 257094
folding the code into the main Analysis library.
There already wasn't much of a distinction between Analysis and IPA.
A number of the passes in Analysis are actually IPA passes, and there
doesn't seem to be any advantage to separating them.
Moreover, it makes it hard to have interactions between analyses that
are both local and interprocedural. In trying to make the Alias Analysis
infrastructure work with the new pass manager, it becomes particularly
awkward to navigate this split.
I've tried to find all the places where we referenced this, but I may
have missed some. I have also adjusted the C API to continue to be
equivalently functional after this change.
Differential Revision: http://reviews.llvm.org/D12075
llvm-svn: 245318
This reverts commit r218918, effectively reapplying r218914 after fixing
an Ocaml bindings test and an Asan crash. The root cause of the latter
was a tightened-up check in `DILexicalBlock::Verify()`, so I'll file a
PR to investigate who requires the loose check (and why).
Original commit message follows.
--
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString. Integers are stringified and
a `\0` character is used as a separator.
Part of PR17891.
Note: I've attached my testcases upgrade scripts to the PR. If I've
just broken your out-of-tree testcases, they might help.
llvm-svn: 219010
This patch addresses the first stage of PR17891 by folding constant
arguments together into a single MDString. Integers are stringified and
a `\0` character is used as a separator.
Part of PR17891.
Note: I've attached my testcases upgrade scripts to the PR. If I've
just broken your out-of-tree testcases, they might help.
llvm-svn: 218914
Add `Value::sortUseList()`, templated on the comparison function to use.
The sort is an iterative merge sort that uses a binomial vector of
already-merged lists to limit the size overhead to `O(1)`.
This is part of PR5680.
llvm-svn: 213824
