Commit Graph

782 Commits

Author SHA1 Message Date
Lei Zhang ac5a50e1e4 Extract openInputFile() into Support/FileUtilities
Multiple binaries have the needs to open input files. Use this function
to de-duplicate the code.

Also changed openOutputFile() to return errors using std::string since
it is a library call and accessing I/O in library call is not friendly.

PiperOrigin-RevId: 228878221
2019-03-29 15:09:11 -07:00
River Riddle e8d0e1f72a Provide dialect hooks for defining named aliases for AffineMap/IntegerSet/Type.
The AsmPrinter will then query registered dialects for aliases of symbols used within the module and use them in place.

PiperOrigin-RevId: 228831678
2019-03-29 15:08:55 -07:00
Nicolas Vasilache cfa5831960 Uniformize composition of AffineApplyOp by construction
This CL is the 5th on the path to simplifying AffineMap composition.
This removes the distinction between normalized single-result AffineMap and
more general composed multi-result map.

One nice byproduct of making the implementation driven by single-result is
that the multi-result extension is a trivial change: the implementation is
still single-result and we just use:

```
unsigned idx = getIndexOf(...);
map.getResult(idx);
```

This CL also fixes an AffineNormalizer implementation issue related to symbols.
Namely it stops performing substitutions on symbols in AffineNormalizer and
instead concatenates them all to be consistent with the call to
`AffineMap::compose(AffineMap)`. This latter call to `compose` cannot perform
simplifications of symbols coming from different maps based on positions only:
i.e. dims are applied and renumbered but symbols must be concatenated.

The only way to determine whether symbols from different AffineApply are the
same is to look at the concrete values. The canonicalizeMapAndOperands is thus
extended with behavior to support replacing operands that appear multiple
times.

Lastly, this CL demonstrates that the implementation is correct by rewriting
ComposeAffineMaps using only `makeComposedAffineApply`. The implementation
uses a matcher because AffineApplyOp are introduced as composed operations on
the fly instead of iteratively forwardSubstituting. For this purpose, a walker
would revisit freshly introduced AffineApplyOp. Regardless, ComposeAffineMaps
is scheduled to disappear, this CL replaces the implementation based on
iterative `forwardSubstitute` by a composed-by-construction
`makeComposedAffineApply`.
Remaining calls to `forwardSubstitute` will be removed in the next CL.

PiperOrigin-RevId: 228830443
2019-03-29 15:08:40 -07:00
Jacques Pienaar fdcfa0bb52 Remove unary, binary, ternary ops from op_base
Previously these were all defined as operating on Tensors which is not true in general. These don't serve much now so just inline it and we can extract it out again.

PiperOrigin-RevId: 228827011
2019-03-29 15:08:25 -07:00
Jacques Pienaar 88e1b9c792 Fix error in checking logic and update tests.
* Check was returning success instead of failure when reporting illegal type;
* TFL ops only support tensor types so update tests with corrected logic.
  - Removed some checks in broadcasting that don't work with tensor input requirement;

PiperOrigin-RevId: 228770184
2019-03-29 15:08:10 -07:00
Uday Bondhugula 2370c601ba Add safeguard against FM explosion
- FM has a worst case exponential complexity. For our purposes, this worst case
  is rarely expected, but could still appear due to improperly constructed
  constraints (a logical/memory error in other methods for eg.) or artificially
  created arbitrarily complex integer sets (adversarial / fuzz tests).

  Add a check to detect such an explosion in the number of constraints and
  conservatively return false from isEmpty() (instead of running out of memory
  or running for too long).

- Add an artifical virus test case.

PiperOrigin-RevId: 228753496
2019-03-29 15:07:55 -07:00
Alex Zinenko 9003490287 Implement branch-free single-division lowering of affine division/remainder
This implements the lowering of `floordiv`, `ceildiv` and `mod` operators from
affine expressions to the arithmetic primitive operations.  Integer division
rules in affine expressions explicitly require rounding towards either negative
or positive infinity unlike machine implementations that round towards zero.
In the general case, implementing `floordiv` and `ceildiv` using machine signed
division requires computing both the quotient and the remainder.  When the
divisor is positive, this can be simplified by adjusting the dividend and the
quotient by one and switching signs.

In the current use cases, we are unlikely to encounter affine expressions with
negative divisors (affine divisions appear in loop transformations such as
tiling that guarantee that divisors are positive by construction).  Therefore,
it is reasonable to use branch-free single-division implementation.  In case of
affine maps, divisors can only be literals so we can check the sign and
implement the case for negative divisors when the need arises.

The affine lowering pass can still fail when applied to semi-affine maps
(division or modulo by a symbol).

PiperOrigin-RevId: 228668181
2019-03-29 15:07:40 -07:00
River Riddle 56b99b4045 Add a few utilities for terminator management:
* Get a specific successor operand.
* Iterator support for non successor operands.
* Fix bug when removing the last operand from the operand list of an Instruction.
* Get the argument number for a BlockArgument.

PiperOrigin-RevId: 228660898
2019-03-29 15:07:25 -07:00
Uday Bondhugula 742c37abc9 Fix DMA overlap pass buffer mapping
- the double buffer should be indexed (iv floordiv step) % 2 and NOT (iv % 2);
  step wasn't being accounted for.

- fix test cases, enable failing test cases

PiperOrigin-RevId: 228635726
2019-03-29 15:07:10 -07:00
Lei Zhang e49e10e4de Replace getAttributeName() with .getName()
PiperOrigin-RevId: 228581178
2019-03-29 15:06:56 -07:00
Lei Zhang 9b034f0bfd Add tblgen::Attribute to wrap around TableGen Attr defs
This CL added a tblgen::Attribute class to wrap around raw TableGen
Record getValue*() calls on Attr defs, which will provide a nicer
API for handling TableGen Record.

PiperOrigin-RevId: 228581107
2019-03-29 15:06:41 -07:00
Alex Zinenko 6ce30becd7 Support verbose parsing and printing of terminator operations
Originally, terminators were special kinds of operation and could not be
extended by dialects.  Only builtin terminators were supported and they had
custom parsers and printers.  Currently, "terminator" is a property of an
operation, making it possible for dialects to define custom terminators.
However, verbose forms of operation syntax were not designed to support
terminators that may have a list of successors (each successor contains a block
name and an optional operand list).  Calling printDefaultOp on a terminator
drops all successor information.  Dialects are thus required to provide custom
parsers and printers for their terminators.

Introduce the syntax for the list of successors in the verbose from of the
operation.  Add support for printing and parsing verbose operations with
successors.

Note that this does not yet add support for unregistered terminators since
"terminator" is a property stored in AsbtractOperation and therefore is only
available for registered operations that have an instance of AbstractOperation.

Add tests for verbose parsing.  It is currently impossible to test round-trip
for verbose terminators because none of the known dialects use verbose syntax
for printing terminators by default, however the printer was exercised on the
LLVM IR dialect prototype.

PiperOrigin-RevId: 228566453
2019-03-29 15:06:26 -07:00
Uday Bondhugula 303c09299f Fix affine expr flattener bug + improve simplification in a particular scenario
- fix visitDivExpr: constraints constructed for localVarCst used the original
  divisor instead of the simplified divisor; fix this. Add a simple test case
  in memref-bound-check that reproduces this bug - although this was encountered in the
  context of slicing for fusion.

- improve mod expr flattening: when flattening mod expressions,
  cancel out the GCD of the numerator and denominator so that we can get a
  simpler flattened form along with a simpler floordiv local var for it

PiperOrigin-RevId: 228539928
2019-03-29 15:06:11 -07:00
Nicolas Vasilache 1f78d63f05 [MLIR] Make SuperVectorization use normalized AffineApplyOp
Supervectorization does not plan on handling multi-result AffineMaps and
non-canonical chains of > 1 AffineApplyOp.
This CL uses the simpler single-result unbounded AffineApplyOp in the
MaterializeVectors pass.

PiperOrigin-RevId: 228469085
2019-03-29 15:05:55 -07:00
Lei Zhang 3e5ee82b81 Put Operator and PredCNF into the tblgen namespace
PiperOrigin-RevId: 228429130
2019-03-29 15:05:38 -07:00
Lei Zhang b2cc2c344e Add tblgen::Type to wrap around TableGen Type defs
This CL added a tblgen::Type class to wrap around raw TableGen
Record getValue*() calls on Type defs, which will provide a
nicer API for handling TableGen Record.

The PredCNF class is also updated to work together with
tblgen::Type.
PiperOrigin-RevId: 228429090
2019-03-29 15:05:23 -07:00
Chris Lattner 2b902f1288 Delete FuncBuilder::createChecked. It is perhaps still a good idea, but has no
clients.  Let's re-add it in the future if there is ever a reason to.  NFC.

Unrelatedly, add a use of a variable to unbreak the non-assert build.

PiperOrigin-RevId: 228284026
2019-03-29 15:05:08 -07:00
Nicolas Vasilache 997415fa77 Extract BuiltinOps::canonicalizeMapAndOperands
This CL is the 4th on the path to simplifying AffineMap composition.
This CL extract canonicalizeMapAndOperands so it can be reused by other
functions; in particular, this will be used in
`makeNormalizedAffineApply`.

PiperOrigin-RevId: 228277890
2019-03-29 15:04:52 -07:00
Nicolas Vasilache 00aac70159 Move makeNormalizedAffineApply
This CL is the 3rd on the path to simplifying AffineMap composition.
This CL just moves `makeNormalizedAffineApply` from VectorAnalysis to
AffineAnalysis where it more naturally belongs.

PiperOrigin-RevId: 228277182
2019-03-29 15:04:38 -07:00
Nicolas Vasilache c6f798a976 Introduce AffineMap::compose(AffineMap)
This CL is the 2nd on the path to simplifying AffineMap composition.
This CL uses the now accepted `AffineExpr::compose(AffineMap)` to
implement `AffineMap::compose(AffineMap)`.

Implications of keeping the simplification function in
Analysis are documented where relevant.

PiperOrigin-RevId: 228276646
2019-03-29 15:04:20 -07:00
River Riddle 8eccc429b7 Add parser support for named type aliases.
Alias identifiers can be used in the place of the types that they alias, and are defined as:

    type-alias-def ::= '!' alias-name '=' 'type' type
    type-alias ::= '!' alias-name

Example:

    !avx.m128 = type vector<4 x f32>
    ...

    "foo"(%x) : vector<4 x f32> -> ()

    // becomes:

    "foo"(%x) : !avx.m128 -> ()

PiperOrigin-RevId: 228271372
2019-03-29 15:04:05 -07:00
Uday Bondhugula e94ba6815a Fix 0-d memref corner case for getMemRefRegion()
- fix crash on test/Transforms/canonicalize.mlir with
  -memref-bound-check

PiperOrigin-RevId: 228268486
2019-03-29 15:03:50 -07:00
Nicolas Vasilache c449e46ceb Introduce AffineExpr::compose(AffineMap)
This CL is the 1st on the path to simplifying AffineMap composition.
This CL uses the now accepted AffineExpr.replaceDimsAndSymbols to
implement `AffineExpr::compose(AffineMap)`.

Arguably, `simplifyAffineExpr` should be part of IR and not Analysis but
this CL does not yet pull the trigger on that.

PiperOrigin-RevId: 228265845
2019-03-29 15:03:36 -07:00
Uday Bondhugula 21baf86a2f Extend loop-fusion's slicing utility + other fixes / updates
- refactor toAffineFromEq and the code surrounding it; refactor code into
  FlatAffineConstraints::getSliceBounds
- add FlatAffineConstraints methods to detect identifiers as mod's and div's of other
  identifiers
- add FlatAffineConstraints::getConstantLower/UpperBound
- Address b/122118218 (don't assert on invalid fusion depths cmdline flags -
  instead, don't do anything; change cmdline flags
  src-loop-depth -> fusion-src-loop-depth
- AffineExpr/Map print method update: don't fail on null instances (since we have
  a wrapper around a pointer, it's avoidable); rationale: dump/print methods should
  never fail if possible.
- Update memref-dataflow-opt to add an optimization to avoid a unnecessary call to
  IsRangeOneToOne when it's trivially going to be true.
- Add additional test cases to exercise the new support
- update a few existing test cases since the maps are now generated uniformly with
  all destination loop operands appearing for the backward slice
- Fix projectOut - fix wrong range for getBestElimCandidate.
- Fix for getConstantBoundOnDimSize() - didn't show up in any test cases since
  we didn't have any non-hyperrectangular ones.

PiperOrigin-RevId: 228265152
2019-03-29 15:03:20 -07:00
Uday Bondhugula b934d75b8f Convert expr - c * (expr floordiv c) to expr mod c in AffineExpr
- Detect 'mod' to replace the combination of floordiv, mul, and subtract when
  possible at construction time; when 'c' is a power of two, this reduces the number of
  operations; also more compact and readable. Update simplifyAdd for this.

  On a side note:
  - with the affine expr flattening we have, a mod expression like d0 mod c
    would be flattened into d0 - c * q,  c * q <= d0 <= c*q + c - 1, with 'q'
    being added as the local variable (q = d0 floordiv c); as a result, a mod
    was turned into a floordiv whenever the expression was reconstructed back,
    i.e., as  d0 - c * (d0 floordiv c); as a result of this change, we recover
    the mod back.

- rename SimplifyAffineExpr -> SimplifyAffineStructures (pass had been renamed but
  the file hadn't been).

PiperOrigin-RevId: 228258120
2019-03-29 15:02:56 -07:00
Uday Bondhugula 56b3640b94 Misc readability and doc / code comment related improvements - NFC
- when SSAValue/MLValue existed, code at several places was forced to create additional
  aggregate temporaries of SmallVector<SSAValue/MLValue> to handle the conversion; get
  rid of such redundant code

- use filling ctors instead of explicit loops

- for smallvectors, change insert(list.end(), ...) -> append(...

- improve comments at various places

- turn getMemRefAccess into MemRefAccess ctor and drop duplicated
  getMemRefAccess. In the next CL, provide getAccess() accessors for load,
  store, DMA op's to return a MemRefAccess.

PiperOrigin-RevId: 228243638
2019-03-29 15:02:41 -07:00
MLIR Team 2cdb59f38d Spelling: bugpone -> bug-prone
PiperOrigin-RevId: 228231744
2019-03-29 15:02:25 -07:00
Jacques Pienaar 00ac2f6eb4 Verify the size of the vector in generated op verify.
PiperOrigin-RevId: 228195756
2019-03-29 15:02:10 -07:00
Lei Zhang f8bbe5deca Various tiny refinements over TableGen Operator class
Use "native" vs "derived" to differentiate attributes on ops: native ones
are specified when creating the op as a part of defining the op, while
derived ones are computed from properties of the op.

PiperOrigin-RevId: 228186962
2019-03-29 15:01:56 -07:00
Jacques Pienaar 65fc8643ec Addresing follow up comments from cl/227991412.
PiperOrigin-RevId: 228185819
2019-03-29 15:01:40 -07:00
River Riddle bee0b83cef Update the langref to include the rationale and specification of the dialect extended type system.
PiperOrigin-RevId: 228184876
2019-03-29 15:01:26 -07:00
River Riddle 3b2c5600d9 Add support for types belonging to unknown dialects. This allows for types to be round tripped even if the dialect that defines them is not linked in. These types will be represented by a new "UnknownType" that uniques them based upon the dialect namespace and raw string type data.
PiperOrigin-RevId: 228184629
2019-03-29 15:01:11 -07:00
Jacques Pienaar aae85ddce1 Match attributes in input pattern.
Bind attributes similar to operands. Use to rewrite leakyreulo and const rewrite pattern. The attribute type/attributes are not currently checked so should only be used where the attributes match due to the construction of the op.

To support current attribute namespacing, convert __ in attribute name to "$" for matching purposes ('$' is not valid character in variable in TableGen).

Some simplification to make it simpler to specify indented ostream and avoid so many spaces. The goal is not to have perfectly formatted code generated but good enough so that its still easy to read for a user.

PiperOrigin-RevId: 228183639
2019-03-29 15:00:55 -07:00
Jacques Pienaar 8d849eb4b9 Add static shape tensor type and rewrite squeeze and reshape rewrites as patterns.
This also moves the predicate declaration in op_base into one section.

PiperOrigin-RevId: 228170793
2019-03-29 15:00:40 -07:00
Alex Zinenko 92a899f629 Drop all uses of the ForInst induction variable before deleting ForInst
The `for` instruction defines the loop induction variable it uses.  In the
well-formed IR, the induction variable can only be used by the body of the
`for` loop.  Existing implementation was explicitly cleaning the body of the
for loop to remove all uses of the induction variable before removing its
definition.  However, in ill-formed IR that may appear in some stages of
parsing, there may be (invalid) users of the loop induction variable outside
the loop body.  In case of unsuccessful parsing, destructor of the
ForInst-defined Value would assert because there are remaining though invalid
users of this Value.  Explicitly drop all uses of the loop induction Value when
destroying a ForInst.  It is no longer necessary to explicitly clean the body
of the loop, destructor of the block will take care of this.

PiperOrigin-RevId: 228168880
2019-03-29 15:00:26 -07:00
Alex Zinenko 3b7b0040ce FunctionParser::~FunctionParser: avoid iterator invalidation
When destroying a FunctionParser in case of parsing failure, we clean up all
uses of undefined forward-declared references.  This has been implemented as
iteration over the list of uses.  However, deleting one use from the list
invalidates the iterator (`IROperand::drop` sets `nextUse` to `nullptr` while
the iterator reads `nextUse` to advance; therefore only the first use was
deleted from the list).  Get a new iterator before calling drop to avoid
invalidation.

PiperOrigin-RevId: 228168849
2019-03-29 15:00:10 -07:00
Uday Bondhugula 94c2d969ce Rename getAffineBinaryExpr -> getAffineBinaryOpExpr, getBinaryAffineOpExpr ->
getAffineBinaryOpExpr for consistency (NFC)

- this is consistent with the name of the class and getAffineDimExpr/ConstantExpr, etc.

PiperOrigin-RevId: 228164959
2019-03-29 14:59:52 -07:00
Nicolas Vasilache 7c0bbe0939 Iterate on vector rather than DenseMap during AffineMap normalization
This CL removes a flakyness associated to a spurious iteration on DenseMap
iterators when normalizing AffineMap.

PiperOrigin-RevId: 228160074
2019-03-29 14:59:37 -07:00
Alex Zinenko c47ed53211 Add simple constant folding hook for CmpIOp
Integer comparisons can be constant folded if both of their arguments are known
constants, which we can compare in the compiler.  This requires implementing
all comparison predicates, but thanks to consistency between LLVM and MLIR
comparison predicates, we have a one-to-one correspondence between predicates
and llvm::APInt comparison functions.  Constant folding of comparsions with
maximum/minimum values of the integer type are left for future work.

This will be used to test the lowering of mod/floordiv/ceildiv in affine
expressions at compile time.

PiperOrigin-RevId: 228077580
2019-03-29 14:59:22 -07:00
Alex Zinenko caa7e70627 LLVM IR lowering: support integer division and remainder operations
These operations trivially map to LLVM IR counterparts for operands of scalar
and (one-dimensional) vector type.  Multi-dimensional vector and tensor type
operands would fail type conversion before the operation conversion takes
place.  Add tests for scalar and vector cases.  Also add a test for vector
`select` instruction for consistency with other tests.

PiperOrigin-RevId: 228077564
2019-03-29 14:59:07 -07:00
Alex Zinenko bc04556cf8 Introduce integer division and remainder operations
This adds signed/unsigned integer division and remainder operations to the
StandardOps dialect.  Two versions are required because MLIR integers are
signless, but the meaning of the leading bit is important in division and
affects the results.  LLVM IR made a similar choice.  Define the operations in
the tablegen file and add simple constant folding hooks in the C++
implementation.  Handle signed division overflow and division by zero errors in
constant folding.  Canonicalization is left for future work.

These operations are necessary to lower affine_apply's down to LLVM IR.

PiperOrigin-RevId: 228077549
2019-03-29 14:58:52 -07:00
Nicolas Vasilache 28cf580555 Cleanup spurious DenseMap include
PiperOrigin-RevId: 228059305
2019-03-29 14:58:38 -07:00
Jacques Pienaar 8f24943826 Verify type of operands match those specifed in op registry.
Expand type to include matcher predicates. Use CNF form to allow specifying combinations of constraints for type. The matching call for the type is used to verify the construction of the operation as well as in rewrite pattern generation.

The matching initially includes redundant checks (e.g., even if the operand of the op is guaranteed to satisfy some requirement, it is still checked during matcher generation for now). As well as some of the traits specified now check what the generated code already checks. Some of the traits can be removed in future as the verify method will include the relevant checks based on the op definition already.

More work is needed for variadic operands.

CNF form is used so that in the follow up redundant checks in the rewrite patterns could be omitted (e.g., when matching a F32Tensor, one does not need to verify that op X's operand 0 is a Tensor if that is guaranteed by op X's definition). The alternative was to have single matcher function specified, but this would not allow for reasoning about what attributes already hold (at the level of PredAtoms).

Use this new operand type restrictions to rewrite BiasAdd with floating point operands as declarative pattern.

PiperOrigin-RevId: 227991412
2019-03-29 14:58:23 -07:00
Nicolas Vasilache 62dabbfd09 Fix opt build failure
PiperOrigin-RevId: 227938032
2019-03-29 14:57:36 -07:00
Uday Bondhugula 8496f2c30b Complete TODOs / cleanup for loop-fusion utility
- this is CL 1/2 that does a clean up and gets rid of one limitation in an
  underlying method - as a result, fusion works for more cases.
- fix bugs/incomplete impl. in toAffineMapFromEq
- fusing across rank changing reshapes for example now just works

  For eg. given a rank 1 memref to rank 2 memref reshape (64 -> 8 x 8) like this,
  -loop-fusion -memref-dataflow-opt now completely fuses and inlines/store-forward
  to get rid of the temporary:

INPUT

  // Rank 1 -> Rank 2 reshape
  for %i0 = 0 to 64 {
     %v = load %A[%i0]
     store %v, %B[%i0 floordiv 8, i0 mod 8]
  }

  for %i1 = 0 to 8
    for %i2 = 0 to 8
      %w = load %B[%i1, i2]
      "foo"(%w) : (f32) -> ()

OUTPUT

$ mlir-opt -loop-fusion -memref-dataflow-opt fuse_reshape.mlir

#map0 = (d0, d1) -> (d0 * 8 + d1)
mlfunc @fuse_reshape(%arg0: memref<64xf32>) {
  for %i0 = 0 to 8 {
    for %i1 = 0 to 8 {
      %0 = affine_apply #map0(%i0, %i1)
      %1 = load %arg0[%0] : memref<64xf32>
      "foo"(%1) : (f32) -> ()
    }
  }
}

AFAIK, there is no polyhedral tool / compiler that can perform such fusion -
because it's not really standard loop fusion, but possible through a
generalized slicing-based approach such as ours.

PiperOrigin-RevId: 227918338
2019-03-29 14:57:22 -07:00
Smit Hinsu d02b08eaf4 Add an example of rank zero tensor in go/mlir-spec
TESTED with preview

PiperOrigin-RevId: 227887054
2019-03-29 14:57:07 -07:00
Smit Hinsu d3339ea2b8 Handle parsing failure for splat elements attribute
Currently, it emits the error but does not terminate parsing.

TESTED with unit test

PiperOrigin-RevId: 227886274
2019-03-29 14:56:52 -07:00
Nicolas Vasilache 618c6a74c6 [MLIR] Introduce normalized single-result unbounded AffineApplyOp
Supervectorization does not plan on handling multi-result AffineMaps and
non-canonical chains of > 1 AffineApplyOp.
This CL introduces a simpler abstraction and composition of single-result
unbounded AffineApplyOp by using the existing unbound AffineMap composition.

This CL adds a simple API call and relevant tests:

```c++
OpPointer<AffineApplyOp> makeNormalizedAffineApply(
  FuncBuilder *b, Location loc, AffineMap map, ArrayRef<Value*> operands);
```

which creates a single-result unbounded AffineApplyOp.
The operands of AffineApplyOp are not themselves results of AffineApplyOp by
consrtuction.

This represent the simplest possible interface to complement the composition
of (mathematical) AffineMap, for the cases when we are interested in applying
it to Value*.

In this CL the composed AffineMap is not compressed (i.e. there exist operands
that are not part of the result). A followup commit will compress to normal
form.

The single-result unbounded AffineApplyOp abstraction will be used in a
followup CL to support the MaterializeVectors pass.

PiperOrigin-RevId: 227879021
2019-03-29 14:56:37 -07:00
River Riddle d2cd083f79 Introduce CRTP TypeBase class to simplify type construction and validation.
This impl class currently provides the following:
* auto definition of the 'ImplType = StorageClass'
* get/getChecked wrappers around TypeUniquer
* 'verifyConstructionInvariants' hook
   - This hook verifies that the arguments passed into get/getChecked are valid
     to construct a type instance with.

With this, all non-generic type uniquing has been moved out of MLIRContext.cpp

PiperOrigin-RevId: 227871108
2019-03-29 14:56:22 -07:00
Chris Lattner 7983bbc251 Introduce a simple canonicalization of affine_apply that drops unused dims and
symbols.

Included with this is some other infra:
 - Testcases for other canonicalizations that I will implement next.
 - Some helpers in AffineMap/Expr for doing simple walks without defining whole
   visitor classes.
 - A 'replaceDimsAndSymbols' facility that I'll be using to simplify maps and
   exprs, e.g. to fold one constant into a mapping and to drop/renumber unused dims.
 - Allow index (and everything else) to work in memref's, as we previously
   discussed, to make the testcase easier to write.
 - A "getAffineBinaryExpr" helper to produce a binop when you know the kind as
   an enum.

This line of work will eventually subsume the ComposeAffineApply pass, but it is no where close to that yet :-)

PiperOrigin-RevId: 227852951
2019-03-29 14:56:07 -07:00