This patch adds supports for union of relations (PresburgerRelation). Along
with this, support for PresburgerSet is also maintained.
This patch is part of a series of patches to add support for relations in
Presburger library.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D121417
This patch remove `spaceKind` from PresburgerSpace, making PresburgerSpace only
a space supporting relations.
Sets are still implemented in the same way, i.e. with a zero domain but instead
the asserts to check if the space is still set are added to users of
PresburgerSpace which treat it as a Set space.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D121357
When `addCoalescedPolyhedron` was called with `j == n - 1`,
the `polyhedrons`-vector was not properly updated (the
`IntegerPolyhedron` at position `n - 2` was "lost"). This patch adds
special handling to that case and a regression testcase.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D121356
This patch moves PresburgerSpace::removeIdRange(idStart, idLimit) to
PresburgerSpace::removeIdRange(kind, idStart, idLimit), i.e. identifiers
can only be removed at once for a single kind.
This makes users of PresburgerSpace to not assume any inside ordering of
identifier kinds.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D121079
This patch cleans up the interface to PresburgerSet. At a high level it does
the following changes:
- Move member functions around to have constructors at top and print/dump
at end.
- Move a private function to be a static function instead.
- Change member functions of type "getAllIntegerPolyhedron" to "getAllPolys"
instead.
- Improve documentation for PresburgerSet.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D121027
This patch makes coalesce skip the comparison of all pairs of IntegerPolyhedrons with LocalIds rather than crash. The heuristics to handle these cases will be upstreamed later on.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D120995
This patch introduces the cut case. If one polytope has only cutting and
redundant inequalities for the other and the facet of the cutting
inequalities are contained within the other polytope, then the polytopes are
be combined into a polytope consisting only of their respective
redundant constraints.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D120614
This patch moves all functionality from IntegerPolyhedron to IntegerRelation.
IntegerPolyhedron is now implemented as a relation with no domain. All existing
functionality is extended to work on relations.
This patch does not affect external users like FlatAffineConstraints as they
can still continue to use IntegerPolyhedron abstraction.
This patch is part of a series of patches to support relations in Presburger
library.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D120652
This patch moves identifier kind specific insert/append functions like
`insertDimId`, `appendSymbolId`, etc. from IntegerPolyhedron to
FlatAffineConstraints.
This change allows for a smoother transition to IntegerRelation.
This change is part of a series of patches to introduce Relations in Presburger
library.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D120576
In the main-loop of the current coalesce implementation `i` was incremented
twice for some cases. This patch fixes this bug and adds a regression
testcase.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D120613
This patch refactors the looping strategy of coalesce for future patches. The new strategy works in-place and uses IneqType to organize inequalities into vectors of the same type. Future coalesce cases will pattern match on this organization. E.g. the contained case needs all inequalities and equalities to be redundant, so this case becomes checking whether the respective vectors are empty. For other cases, the patterns consider the types of all inequalities of both sets making it wasteful to only consider whether a can be coalesced with b in one step, as inequalities would need to be typed again for the opposite case. Therefore, the new strategy tries to coalesce a with b and b with a in a single step.
Reviewed By: Groverkss, arjunp
Differential Revision: https://reviews.llvm.org/D120392
This patch moves the Presburger library to a new `presburger` namespace.
This allows to shorten some names, helps to avoid polluting the mlir namespace,
and also provides some structure.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D120505
Use an `MLIRContext` declared in a single place in the `parsePoly` function that almost all Presburger unit tests use for parsing sets. This function is only used in tests.
This saves us from having to declare and pass a new `MLIRContext` in every test.
Reviewed By: bondhugula, mehdi_amini
Differential Revision: https://reviews.llvm.org/D119251
This patch adds typing of inequalities to the simplex. This is a cental part of the coalesce algorithm and will be heavily used in later coalesce patches. Currently, only the three most basic types are supported with more to be introduced when they are needed.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D119925
This allows to differentiate between the cases where the optimum does not
exist due to being unbounded and due to the polytope being empty.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D120127
This patch introducing seperating dimensions into two types: Domain and Range.
This allows building relations over PresburgerSpace.
This patch is part of a series of patches to introduce relations in Presburger
library.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D119709
Add support for computing an overapproximation of the number of integer points
in a polyhedron. The returned result is actually the number of integer points
one gets by computing the "rational shadow" obtained by projecting out the
local IDs, finding the minimal axis-parallel hyperrectangular approximation
of the shadow, and returning the number of integer points in that. This does
not currently support symbols.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D119228
Add the class MultiAffineFunction which represents functions whose domain is an
IntegerPolyhedron and which produce an output given by a tuple of affine
expressions in the IntegerPolyhedron's ids.
Also add support for piece-wise MultiAffineFunctions, which are defined on a
union of IntegerPolyhedrons, and may have different output affine expressions
on each IntegerPolyhedron. Thus the function is affine on each individual
IntegerPolyhedron piece in the domain.
This is part of a series of patches leading up to parametric integer programming.
Depends on D118778.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D118779
Use `SmallVector` instead of `std::vector` in `getLocalRepr` function.
Also, fix the casing of a variable.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D118722
Extract the division representation from equality constraints.
For example:
32*k == 16*i + j - 31 <-- k is the localVariable
expr = 16*i + j - 31, divisor = 32
k = (16*i + j - 32) floordiv 32
The dividend of the division is set to [16, 1, -32] and the divisor is set
to 32.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D117959
This patch introduces a class LexSimplex that can currently be used to find the
lexicographically minimal rational point in an IntegerPolyhedron. This is a
series of patches leading to computing the lexicographically minimal integer
lattice point as well parametric lexicographic minimization.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D117437
When the coefficients of dividend are negative, the gcd may be negative
which will change the sign of dividend and overflow denominator.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D117911
The current state of the top level Analysis/ directory is that it contains two libraries;
a generic Analysis library (free from dialect dependencies), and a LoopAnalysis library
that contains various analysis utilities that originated from Affine loop transformations.
This commit moves the LoopAnalysis to the more appropriate home of `Dialect/Affine/Analysis/`,
given the use and intention of the majority of the code within it. After the move, if there
are generic utilities that would fit better in the top-level Analysis/ directory, we can move
them.
Differential Revision: https://reviews.llvm.org/D117351
This patch moves PresburgerSet to Presburger/ directory. This patch is purely
mechincal, it only moves and renames functionality and tests.
This patch is part of a series of patches to move presburger functionality to
Presburger/ directory.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D116836
This patch moves all presburger functionality from FlatAffineConstraints to
IntegerPolyhedron. This patch is purely mechanical, it only moves and renames
functionality and tests.
This patch is part of a series of patches to move presburger functionality to
Presburger/ directory.
Reviewed By: bondhugula
Differential Revision: https://reviews.llvm.org/D116681
This commits adds division normalization in the `getDivRepr` function which extracts
the gcd from the dividend and divisor and normalizes them.
Signed-off-by: Prashant Kumar <pk5561@gmail.com>
Reviewed By: bondhugula
Differential Revision: https://reviews.llvm.org/D115595
This patch moves LinearTransform to Presburger/ and makes it use
IntegerPolyhedron instead of FlatAffineConstraints. Also modifies its usage in
`FlatAffineConstraints::findIntegerSample` to support the changes.
This patch is part of a series of patches for moving presburger math functionality into Presburger directory.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D116311
This patch replaces usage of FlatAffineConstraints in Simplex with
IntegerPolyhedron. This removes dependency of Simplex on FlatAffineConstraints
and puts it on IntegerPolyhedron, which is part of Presburger library.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D116287
This commit rewrites most existing unittests involving FlatAffineConstraints
to use the parsing utility. This helps to make the tests more understandable.
This relands commit b0e8667b1d, which was
reverted in 6963be1276, with a fix to a unittest
which was incorrectly rewritten before.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D115920
This reverts commit b0e8667b1d.
ASAN/UBSAN bot is broken with this trace:
[ RUN ] FlatAffineConstraintsTest.FindSampleTest
llvm-project/mlir/include/mlir/Support/MathExtras.h:27:15: runtime error: signed integer overflow: 1229996100002 * 809999700000 cannot be represented in type 'long'
#0 0x7f63ace960e4 in mlir::ceilDiv(long, long) llvm-project/mlir/include/mlir/Support/MathExtras.h:27:15
#1 0x7f63ace8587e in ceil llvm-project/mlir/include/mlir/Analysis/Presburger/Fraction.h:57:42
#2 0x7f63ace8587e in operator* llvm-project/llvm/include/llvm/ADT/STLExtras.h:347:42
#3 0x7f63ace8587e in uninitialized_copy<llvm::mapped_iterator<mlir::Fraction *, long (*)(mlir::Fraction), long>, long *> include/c++/v1/__memory/uninitialized_algorithms.h:36:62
#4 0x7f63ace8587e in uninitialized_copy<llvm::mapped_iterator<mlir::Fraction *, long (*)(mlir::Fraction), long>, long *> llvm-project/llvm/include/llvm/ADT/SmallVector.h:490:5
#5 0x7f63ace8587e in append<llvm::mapped_iterator<mlir::Fraction *, long (*)(mlir::Fraction), long>, void> llvm-project/llvm/include/llvm/ADT/SmallVector.h:662:5
#6 0x7f63ace8587e in SmallVector<llvm::mapped_iterator<mlir::Fraction *, long (*)(mlir::Fraction), long> > llvm-project/llvm/include/llvm/ADT/SmallVector.h:1204:11
#7 0x7f63ace8587e in mlir::FlatAffineConstraints::findIntegerSample() const llvm-project/mlir/lib/Analysis/AffineStructures.cpp:1171:27
#8 0x7f63ae95a84d in mlir::checkSample(bool, mlir::FlatAffineConstraints const&, mlir::TestFunction) llvm-project/mlir/unittests/Analysis/AffineStructuresTest.cpp:37:23
#9 0x7f63ae957545 in mlir::FlatAffineConstraintsTest_FindSampleTest_Test::TestBody() llvm-project/mlir/unittests/Analysis/AffineStructuresTest.cpp:222:3
This commit rewrites most existing unittests involving FlatAffineConstraints to use the parsing utility. This helps to make the tests more understandable.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D115920
When subtracting `b \ c`, when there are divisions in `c`, these division
constraints get added to `b`. `b` must be restored to its original state
when returning, but these added divisions constraints were not removed in
one of the return paths. This patch fixes this and deduplicates the
restoration logic by encapuslating it in a lambda `restoreState`. The patch
also includes a regression test for the bug fix.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D115577
This patch adds support for extracting divisions when the set contains bounds
which are tighter than the division bounds. For example:
```
3q - i + 2 >= 0 <-- Lower bound for 'q'
-3q + i - 1 >= 0 <-- Tighter upper bound for 'q'
```
Here, the actual upper bound for division for `q` would be `-3q + i >= 0`, but
since this actual upper bound is implied by a tighter upper bound, which awe can still
extract the divison.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D115096
The method that was previously used for computing dual variables was incorrect.
This was used in the integer emptiness check algorithm, where this bug could lead to much longer running times. (Due to the way it is used, this never results in an incorrect emptiness check result.)
This patch fixes the dual computation and adds some additional asserts that catch this bug, along with regression test cases that trigger the asserts when the incorrect dual computation is used.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D113803
This patch factors out math functionality that is a subset of Presburger arithmetic and moves it from FlatAffineConstraints to Presburger/IntegerPolyhedron. This patch only moves some parts of the functionality planned to be moved, with subsequent patches moving more functionality. There are three main reasons for this:
1. This split makes the Presburger Library easier and more flexible to use
across MLIR, by not depending on IR.
2. This split allows the Presburger library to be developed independently from
Affine Analysis, with Affine Analysis using this library.
3. With more functionality being upstreamed to the Presburger Library, the
mlir/Analysis directory will be cluttered with Presburger library components
since they depend on math functionality from FlatAffineConstraints. Moving this
functionality to the Presburger directory allows keeping the new functionality
in the Presburger directory.
This patch is part of an ongoing effort to make the Presburger Library easier to use. The motivation for this effort is the feedback received at the LLVM conference from Mehdi and others.
Reviewed By: bondhugula
Differential Revision: https://reviews.llvm.org/D114674
This patch provides functionality for simplifying `PresburgerSet`s by checking if any `FlatAffineConstraints` in the set is contained in another, and removing such redundant FACs.
This is part of a series of patches to provide functionality for [integer set coalescing](http://impact.gforge.inria.fr/impact2015/papers/impact2015-verdoolaege.pdf) in MLIR.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D110617