2 Commits

Author SHA1 Message Date
Uday Bondhugula
0122a99cbb Affine expression analysis and simplification.
Outside of IR/
- simplify a MutableAffineMap by flattening the affine expressions
- add a simplify affine expression pass that uses this analysis
- update the FlatAffineConstraints API (to be used in the next CL)

In IR:
- add isMultipleOf and getKnownGCD for AffineExpr, and make the in-IR
  simplication of simplifyMod simpler and more powerful.
- rename the AffineExpr visitor methods to distinguish b/w visiting and
  walking, and to simplify API names based on context.

The next CL will use some of these for the loop unrolling/unroll-jam to make
the detection for the need of cleanup loop powerful/non-trivial.

A future CL will finally move this simplification to FlatAffineConstraints to
make it more powerful. For eg., currently, even if a mod expr appearing in a
part of the expression tree can't be simplified, the whole thing won't be
simplified.

PiperOrigin-RevId: 211012256
2019-03-29 13:07:44 -07:00
Uday Bondhugula
851353687f Introduce hyper-rectangular sets for analysis.
- introduce hyper-rectangular set representation and API sketch for
  analysis/code generation
- implement the 'intersect' and 'project out' operations.

The represention is lighter weight, and operations and other queries on it are
much faster on such domains when compared to general polyhedral domains.

PiperOrigin-RevId: 210245882
2019-03-29 13:05:29 -07:00