The Presburger library currently uses int64_t throughout for its integers.
This runs the risk of silently producing incorrect results when overflows occur.
Fixing this issue requires some sort of multiprecision integer
that transparently supports aribtrary arithmetic computations.
The class SlowMPInt provides this functionality, and is intended to be used
as the slow path fallback for a more optimized upcoming class, MPInt, that optimizes
for the Presburger library's workloads.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D123758
This patch allows attaching user information, called "values" to each
identifier. The values are used to carry information along with variables and
are also used to determine if two variables are identical.
This patch is part of a series of patches to allow attaching user information
with variables in Presburger library.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D127347
Using "default:" in the switch statemements that handle all our
merger ops has become a bit cumbersome since it is easy to overlook
parts of the code that need to handle ops specifically. By enforcing
full switch statements without "default:", we get a compiler warning
when cases are overlooked.
Reviewed By: wrengr
Differential Revision: https://reviews.llvm.org/D127263
When constraints in the two operands make each other redundant, prefer constraints of the second because this affects the number of sets in the output at each level; reducing these can help prevent exponential blowup.
This is accomplished by adding extra overloads to Simplex::detectRedundant that only scan a subrange of the constraints for redundancy.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D127237
This patch fixes a bug in PresburgeRelation::subtract that made it process the
inequality at index 0, multiple times. This was caused by allocating memory
instead of reserving memory in llvm::SmallVector.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D127228
This commit defines a dataflow analysis for integer ranges, which
uses a newly-added InferIntRangeInterface to compute the lower and
upper bounds on the results of an operation from the bounds on the
arguments. The range inference is a flow-insensitive dataflow analysis
that can be used to simplify code, such as by statically identifying
bounds checks that cannot fail in order to eliminate them.
The InferIntRangeInterface has one method, inferResultRanges(), which
takes a vector of inferred ranges for each argument to an op
implementing the interface and a callback allowing the implementation
to define the ranges for each result. These ranges are stored as
ConstantIntRanges, which hold the lower and upper bounds for a
value. Bounds are tracked separately for the signed and unsigned
interpretations of a value, which ensures that the impact of
arithmetic overflows is correctly tracked during the analysis.
The commit also adds a -test-int-range-inference pass to test the
analysis until it is integrated into SCCP or otherwise exposed.
Finally, this commit fixes some bugs relating to the handling of
region iteration arguments and terminators in the data flow analysis
framework.
Depends on D124020
Depends on D124021
Reviewed By: rriddle, Mogball
Differential Revision: https://reviews.llvm.org/D124023
This patch adds support for applying a relation on domain/range of a relation.
Reviewed By: arjunp, ftynse
Differential Revision: https://reviews.llvm.org/D126339
This patch adds support for obtaining a set corresponding to the domain/range
of the relation.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D126326
This diff updates the LLVMIR dialect Fastmath flags attribute to use recently
added features of `BitEnum` attributes. Specifically, this diff uses the bit
enum "group" case to represent the `fast` value as an alias for a combination
of other values (`ninf`, `nnan`, ...), instead of using a separate integer
value. (This is in line with LLVM's fastmath flags representation.) This diff
also leverages the `printBitEnumPrimaryGroups` `tblgen` field for concise
enum printing.
The `BitEnum` features were developed for an upcoming diff that adds `fastmath`
support to the arithmetic dialect. This diff simply applies some of the relevant
new features to the LLVM dialect attribute.
Reviewed By: ftynse, Mogball
Differential Revision: https://reviews.llvm.org/D124720
There are a lot of cases where we accidentally ignored the result of some
parsing hook. Mark ParseResult as LLVM_NODISCARD just like ParseResult is.
This exposed some stuff to clean up, so do.
Differential Revision: https://reviews.llvm.org/D125549
This allows for inferring the result types of operations in certain situations by using the type of
an operand. This commit allowed for automatically supporting type inference for many more
operations with no additional effort, e.g. nearly all Arithmetic operations now support
result type inferrence with no additional changes.
Differential Revision: https://reviews.llvm.org/D124581
This diff introduces a tablegen field for bit enum attributes
(`printBitEnumPrimaryGroups`) to control printing when the enum uses "group"
cases. An example would be an implementation that uses a `fastmath` enum value
as an alias for individual fastmath flags. The proposed field would allow
printing of simply `fast` for the enum value, instead of the more verbose list
that would include `fast` as well as the individual flags (e.g. `reassoc,nnan,
ninf,nsz,arcp,contract,afn,fast`).
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D123871
Add helper functions to check if an op may be executed multiple times based on RegionBranchOpInterface.
Differential Revision: https://reviews.llvm.org/D123789
This patch modifies mergeLocalIds to not delete duplicate local ids in
`this` relation. This allows the ordering of the final local ids for `this`
to be determined more easily, which is generally required when other objects
refer to these local ids.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D123866
This diff moves `EnumAttr` tablegen definitions (specifically, `IntEnumAttr` and
`BitEnumAttr`-related classes) from `OpBase.td` to `EnumAttr.td`. No
functionality is changed.
Reviewed By: rriddle
Differential Revision: https://reviews.llvm.org/D123551
StrEnumAttr has been deprecated in favour of EnumAttr, a solution based on AttrDef (https://reviews.llvm.org/D115181). This patch removes StrEnumAttr, along with all the custom ODS logic required to handle it.
See https://discourse.llvm.org/t/psa-stop-using-strenumattr-do-use-enumattr/5710 on how to transition to EnumAttr. In short,
```
// Before
def MyEnumAttr : StrEnumAttr<"MyEnum", "", [
StrEnumAttrCase<"A">,
StrEnumAttrCase<"B">
]>;
// After (pick an integer enum of your choice)
def MyEnum : I32EnumAttr<"MyEnum", "", [
I32EnumAttrCase<"A", 0>,
I32EnumAttrCase<"B", 1>
]> {
// Don't generate a C++ class! We want to use the AttrDef
let genSpecializedAttr = 0;
}
// Define the AttrDef
def MyEnum : EnumAttr<MyDialect, MyEnum, "my_enum">;
```
Reviewed By: rriddle, jpienaar
Differential Revision: https://reviews.llvm.org/D120834
This diff contains:
- Parameterization of bit enum attributes in OpBase.td by bit width (e.g. 32
and 64). Previously, all enums were 32-bits. This brings enum functionality in
line with other integer attributes, and allows for bit enums greater than 32
bits.
- SPIRV and Vector dialects were updated to use bit enum attributes with an
explicit bit width
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D123095
With the introduction of IntegerPolyhedron and IntegerRelation in Presburger
directory, the purpose of FlatAffineConstraints becomes redundant. For users
requiring Presburger arithmetic without IR information, Presburger library can
directly be used. For users requiring IR information,
FlatAffineValueConstraints can be used.
This patch merges FAC and FACV to remove redundancy of FAC.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D122476
Add support for computing the symbolic integer lexmin of a polyhedron.
This finds, for every assignment to the symbols, the lexicographically
minimum value attained by the dimensions. For example, the symbolic lexmin
of the set
`(x, y)[a, b, c] : (a <= x, b <= x, x <= c)`
can be written as
```
x = a if b <= a, a <= c
x = b if a < b, b <= c
```
This also finds the set of assignments to the symbols that make the lexmin unbounded.
This was previously landed in da92f92621 and
reverted in b238c252e8 due to a build failure
in the code. Re-landing now with a fixed build.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122985
Add support for computing the symbolic integer lexmin of a polyhedron.
This finds, for every assignment to the symbols, the lexicographically
minimum value attained by the dimensions. For example, the symbolic lexmin
of the set
`(x, y)[a, b, c] : (a <= x, b <= x, x <= c)`
can be written as
```
x = a if b <= a, a <= c
x = b if a < b, b <= c
```
This also finds the set of assignments to the symbols that make the lexmin unbounded.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122985
This commit restructures how TypeID is implemented to ideally avoid
the current problems related to shared libraries. This is done by changing
the "implicit" fallback path to use the name of the type, instead of using
a static template variable (which breaks shared libraries). The major downside to this
is that it adds some additional initialization costs for the implicit path. Given the
use of type names for uniqueness in the fallback, we also no longer allow types
defined in anonymous namespaces to have an implicit TypeID. To simplify defining
an ID for these classes, a new `MLIR_DEFINE_EXPLICIT_INTERNAL_INLINE_TYPE_ID` macro
was added to allow for explicitly defining a TypeID directly on an internal class.
To help identify when types are using the fallback, `-debug-only=typeid` can be
used to log which types are using implicit ids.
This change generally only requires changes to the test passes, which are all defined
in anonymous namespaces, and thus can't use the fallback any longer.
Differential Revision: https://reviews.llvm.org/D122775
Add integer-exact checks for inequalities being separate and redundant in LexSimplex.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122921
Previously, when an input set had a duplicate division, the duplicates might
be removed by a call to mergeLocalIds due to being detected as being duplicate
for the first time. The subtraction implementation cannot handle existing
locals being removed, so this would lead to unexpected behaviour. Resolve this
by removing all the duplicates up front.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122826
This patch modifies IntegerPolyhedron, IntegerRelation, PresburgerRelation,
PresburgerSet, PWMAFunction, constructors to take PresburgerSpace instead of
dimensions. This allows information present in PresburgerSpace to be carried
better and allows for a general interface.
Reviewed By: arjunp
Differential Revision: https://reviews.llvm.org/D122842
Previously, when updating the outputs matrix, the local offset was not being considered.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122812
This reverts commit 5630143af3. The
implementation in this commit was incorrect. Also, handling this representation
of equalities in the upcoming support for symbolic lexicographic minimization
makes that patch much more complex. It will be easier to review that without
this representaiton and then reintroduce the fixed column representation
later, hence the revert rather than a bug fix.
Add a baseline implementation of support for local ids for `PWMAFunction::valueAt`. This can be made more efficient later if needed by handling locals with known div representations separately.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122144
In LexSimplex, instead of adding equalities as a pair of inequalities,
add them as a single row, move them into the basis, and keep them there.
There will always be a valid basis involving all non-redundant equalities. Such
equalities will then be ignored in some other operations, such as when looking
for pivot columns. This speeds them up a little bit.
More importantly, this is an important precursor patch to adding support for
symbolic integer lexmin, as this heuristic can sometimes make a big difference there.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122165
This is a convenience function for adding new divisions to the Simplex given the numerator and denominator.
This will be needed for symbolic integer lexmin support.
Reviewed By: Groverkss
Differential Revision: https://reviews.llvm.org/D122159
Arjun P