This allows to use OperationEquivalence to track structural comparison for equality
between two operations.
Differential Revision: https://reviews.llvm.org/D106422
I backed this off to make the previous patch easier to wrangle, but now
this is an efficient query and it is better to not replace it in CSE.
Differential Revision: https://reviews.llvm.org/D103494
The previous impl densely scanned the entire region starting with an op
when dominators were created, creating a DominatorTree for every region.
This is extremely expensive up front -- particularly for clients like
Linalg/Transforms/Fusion.cpp that construct DominanceInfo for a single
query. It is also extremely memory wasteful for IRs that use single
block regions commonly (e.g. affine.for) because it's making a
dominator tree for a region that has trivial dominance. The
implementation also had numerous unnecessary minor efficiencies, e.g.
doing multiple walks of the region tree or tryGetBlocksInSameRegion
building a DenseMap that it didn't need.
This patch switches to an approach where [Post]DominanceInfo is free
to construct, and which lazily constructs DominatorTree's for any
multiblock regions that it needs. This avoids the up-front cost
entirely, making its runtime proportional to the complexity of the
region tree instead of # ops in a region. This also avoids the memory
and time cost of creating DominatorTree's for single block regions.
Finally this rewrites the implementation for simplicity and to avoids
the constant factor problems the old implementation had.
Differential Revision: https://reviews.llvm.org/D103384
CSE is the only client of this API, refactor it a bit to pull the query
internally to make changes to DominanceInfo a bit easier. This commit
also improves comments a bit.
If an operation has been inserted as a key in to the known values
hashtable, then it can not be modified in a way which changes its hash.
This change avoids modifying the operands of any previously recorded
operation, which prevents their hash from changing.
In an SSACFG region, it is impossible to visit an operation before
visiting its operands, so this is not a problem. This situation can only
happen in regions without strict dominance, such as graph regions.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D99486
These properties were useful for a few things before traits had a better integration story, but don't really carry their weight well these days. Most of these properties are already checked via traits in most of the code. It is better to align the system around traits, and improve the performance/cost of traits in general.
Differential Revision: https://reviews.llvm.org/D96088
Some dialects have semantics which is not well represented by common
SSA structures with dominance constraints. This patch allows
operations to declare the 'kind' of their contained regions.
Currently, two kinds are allowed: "SSACFG" and "Graph". The only
difference between them at the moment is that SSACFG regions are
required to have dominance, while Graph regions are not required to
have dominance. The intention is that this Interface would be
generated by ODS for existing operations, although this has not yet
been implemented. Presumably, if someone were interested in code
generation, we might also have a "CFG" dialect, which defines control
flow, but does not require SSA.
The new behavior is mostly identical to the previous behavior, since
registered operations without a RegionKindInterface are assumed to
contain SSACFG regions. However, the behavior has changed for
unregistered operations. Previously, these were checked for
dominance, however the new behavior allows dominance violations, in
order to allow the processing of unregistered dialects with Graph
regions. One implication of this is that regions in unregistered
operations with more than one op are no longer CSE'd (since it
requires dominance info).
I've also reorganized the LangRef documentation to remove assertions
about "sequential execution", "SSA Values", and "Dominance". Instead,
the core IR is simply "ordered" (i.e. totally ordered) and consists of
"Values". I've also clarified some things about how control flow
passes between blocks in an SSACFG region. Control Flow must enter a
region at the entry block and follow terminator operation successors
or be returned to the containing op. Graph regions do not define a
notion of control flow.
see discussion here:
https://llvm.discourse.group/t/rfc-allowing-dialects-to-relax-the-ssa-dominance-condition/833/53
Differential Revision: https://reviews.llvm.org/D80358
Summary:
Almost all uses of these iterators, including implicit ones, really
only need the const variant (as it should be). The only exception is
in NewGVN, which changes the order of dominator tree child nodes.
Change-Id: I4b5bd71e32d71b0c67b03d4927d93fe9413726d4
Reviewers: arsenm, RKSimon, mehdi_amini, courbet, rriddle, aartbik
Subscribers: wdng, Prazek, hiraditya, kuhar, rogfer01, rriddle, jpienaar, shauheen, antiagainst, nicolasvasilache, arpith-jacob, mgester, lucyrfox, aartbik, liufengdb, stephenneuendorffer, Joonsoo, grosul1, vkmr, Kayjukh, jurahul, msifontes, cfe-commits, llvm-commits
Tags: #clang, #mlir, #llvm
Differential Revision: https://reviews.llvm.org/D83087
These libraries are distinct from other things in Analysis in that they
operate only on core IR concepts. This also simplifies dependencies
so that Dialect -> Analysis -> Parser -> IR. Previously, the parser depended
on portions of the the Analysis directory as well, which sometimes
caused issues with the way the cmake makefile generator discovers
dependencies on generated files during compilation.
Differential Revision: https://reviews.llvm.org/D79240
This provides a general hash and comparison for checking if two operations are equivalent. This revision also optimizes the handling of result types to take advantage of how result types are stored on the operation.
Differential Revision: https://reviews.llvm.org/D79029
Makes the relationship and function clearer. Accordingly rename getAttrList to getMutableAttrDict.
Differential Revision: https://reviews.llvm.org/D79125
Summary:
This is much cleaner, and fits the same structure as many other tablegen backends. This was not done originally as the CRTP in the pass classes made it overly verbose/complex.
Differential Revision: https://reviews.llvm.org/D77367
This revision removes all of the CRTP from the pass hierarchy in preparation for using the tablegen backend instead. This creates a much cleaner interface in the C++ code, and naturally fits with the rest of the infrastructure. A new utility class, PassWrapper, is added to replicate the existing behavior for passes not suitable for using the tablegen backend.
Differential Revision: https://reviews.llvm.org/D77350
This revision adds support for generating utilities for passes such as options/statistics/etc. that can be inferred from the tablegen definition. This removes additional boilerplate from the pass, and also makes it easier to remove the reliance on the pass registry to provide certain things(e.g. the pass argument).
Differential Revision: https://reviews.llvm.org/D76659
This will greatly simplify a number of things related to passes:
* Enables generation of pass registration
* Enables generation of boiler plate pass utilities
* Enables generation of pass documentation
This revision focuses on adding the basic structure and adds support for generating the registration for passes in the Transforms/ directory. Future revisions will add more support and move more passes over.
Differential Revision: https://reviews.llvm.org/D76656
HasNoSideEffect can now be implemented using the MemoryEffectInterface, removing the need to check multiple things for the same information. This also removes an easy foot-gun for users as 'Operation::hasNoSideEffect' would ignore operations that dynamically, or recursively, have no side effects. This also leads to an immediate improvement in some of the existing users, such as DCE, now that they have access to more information.
Differential Revision: https://reviews.llvm.org/D76036
These terminator operations don't really have any side effects, and this allows for more accurate side-effect analysis for region operations. For example, currently we can't detect like a loop.for or affine.for are dead because the affine.terminator is "side effecting".
Note: Marking as NoSideEffect doesn't mean that these operations can be opaquely erased.
Differential Revision: https://reviews.llvm.org/D75888
Summary: The new internal representation of operation results now allows for accessing the result types to be more efficient. Changing the API to ArrayRef is more efficient and removes the need to explicitly materialize vectors in several places.
Differential Revision: https://reviews.llvm.org/D73429
Statistics are a way to keep track of what the compiler is doing and how effective various optimizations are. It is useful to see what optimizations are contributing to making a particular program run faster. Pass-instance specific statistics take this even further as you can see the effect of placing a particular pass at specific places within the pass pipeline, e.g. they could help answer questions like "what happens if I run CSE again here".
Statistics can be added to a pass by simply adding members of type 'Pass::Statistics'. This class takes as a constructor arguments: the parent pass pointer, a name, and a description. Statistics can be dumped by the pass manager in a similar manner to how pass timing information is dumped, i.e. via PassManager::enableStatistics programmatically; or -pass-statistics and -pass-statistics-display via the command line pass manager options.
Below is an example:
struct MyPass : public OperationPass<MyPass> {
Statistic testStat{this, "testStat", "A test statistic"};
void runOnOperation() {
...
++testStat;
...
}
};
$ mlir-opt -pass-pipeline='func(my-pass,my-pass)' foo.mlir -pass-statistics
Pipeline Display:
===-------------------------------------------------------------------------===
... Pass statistics report ...
===-------------------------------------------------------------------------===
'func' Pipeline
MyPass
(S) 15 testStat - A test statistic
MyPass
(S) 6 testStat - A test statistic
List Display:
===-------------------------------------------------------------------------===
... Pass statistics report ...
===-------------------------------------------------------------------------===
MyPass
(S) 21 testStat - A test statistic
PiperOrigin-RevId: 284022014
This allows for them to be used on other non-function, or even other function-like, operations. The algorithms are already generic, so this is simply changing the derived pass type. The majority of this change is just ensuring that the nesting of these passes remains the same, as the pass manager won't auto-nest them anymore.
PiperOrigin-RevId: 276573038
Switch to C++14 standard method as llvm::make_unique has been removed (
https://reviews.llvm.org/D66259). Also mark some targets as c++14 to ease next
integrates.
PiperOrigin-RevId: 263953918
Since raw pointers are always passed around for IR construct without
implying any ownership transfer, it can be error prone to have implicit
ownership transferred the same way.
For example this code can seem harmless:
Pass *pass = ....
pm.addPass(pass);
pm.addPass(pass);
pm.run(module);
PiperOrigin-RevId: 263053082
These methods will allow replacing the uses of results with an existing operation, with the same number of results, or a range of values. This removes a number of hand-rolled result replacement loops and simplifies replacement for operations with multiple results.
PiperOrigin-RevId: 262206600
a pointer. This makes it consistent with all the other methods in
FunctionPass, as well as with ModulePass::getModule(). NFC.
PiperOrigin-RevId: 240257910
- change this for consistency - everything else similar takes/returns a
Function pointer - the FuncBuilder ctor,
Block/Value/Instruction::getFunction(), etc.
- saves a whole bunch of &s everywhere
PiperOrigin-RevId: 236928761
An analysis can be any class, but it must provide the following:
* A constructor for a given IR unit.
struct MyAnalysis {
// Compute this analysis with the provided module.
MyAnalysis(Module *module);
};
Analyses can be accessed from a Pass by calling either the 'getAnalysisResult<AnalysisT>' or 'getCachedAnalysisResult<AnalysisT>' methods. A FunctionPass may query for a cached analysis on the parent module with 'getCachedModuleAnalysisResult'. Similary, a ModulePass may query an analysis, it doesn't need to be cached, on a child function with 'getFunctionAnalysisResult'.
By default, when running a pass all cached analyses are set to be invalidated. If no transformation was performed, a pass can use the method 'markAllAnalysesPreserved' to preserve all analysis results. As noted above, preserving specific analyses is not yet supported.
PiperOrigin-RevId: 236505642
Mehdi Amini