34 Commits

Author SHA1 Message Date
Smit Hinsu
adca59e4f7 Return bool from all emitError methods similar to Operation::emitOpError
This simplifies call-sites returning true after emitting an error. After the
conversion, dropped braces around single statement blocks as that seems more
common.

Also, switched to emitError method instead of emitting Error kind using the
emitDiagnostic method.

TESTED with existing unit tests

PiperOrigin-RevId: 224527868
2019-03-29 14:22:06 -07:00
Nicolas Vasilache
4adc169bd0 [MLIR] Add AffineMap composition and use it in Materialization
This CL adds the following free functions:
```
/// Returns the AffineExpr e o m.
AffineExpr compose(AffineExpr e, AffineMap m);
/// Returns the AffineExpr f o g.
AffineMap compose(AffineMap f, AffineMap g);
```

This addresses the issue that AffineMap composition is only available at a
distance via AffineValueMap and is thus unusable on Attributes.
This CL thus implements AffineMap composition in a more modular and composable
way.

This CL does not claim that it can be a good replacement for the
implementation in AffineValueMap, in particular it does not support bounded
maps atm.

Standalone tests are added that replicate some of the logic of the AffineMap
composition pass.

Lastly, affine map composition is used properly inside MaterializeVectors and
a standalone test is added that requires permutation_map composition with a
projection map.

PiperOrigin-RevId: 224376870
2019-03-29 14:20:22 -07:00
Nicolas Vasilache
df0a25efee [MLIR] Add support for permutation_map
This CL hooks up and uses permutation_map in vector_transfer ops.
In particular, when going into the nuts and bolts of the implementation, it
became clear that cases arose that required supporting broadcast semantics.
Broadcast semantics are thus added to the general permutation_map.
The verify methods and tests are updated accordingly.

Examples of interest include.

Example 1:
The following MLIR snippet:
```mlir
   for %i3 = 0 to %M {
     for %i4 = 0 to %N {
       for %i5 = 0 to %P {
         %a5 = load %A[%i4, %i5, %i3] : memref<?x?x?xf32>
   }}}
```
may vectorize with {permutation_map: (d0, d1, d2) -> (d2, d1)} into:
```mlir
   for %i3 = 0 to %0 step 32 {
     for %i4 = 0 to %1 {
       for %i5 = 0 to %2 step 256 {
         %4 = vector_transfer_read %arg0, %i4, %i5, %i3
              {permutation_map: (d0, d1, d2) -> (d2, d1)} :
              (memref<?x?x?xf32>, index, index) -> vector<32x256xf32>
   }}}
````
Meaning that vector_transfer_read will be responsible for reading the 2-D slice:
`%arg0[%i4, %i5:%15+256, %i3:%i3+32]` into vector<32x256xf32>. This will
require a transposition when vector_transfer_read is further lowered.

Example 2:
The following MLIR snippet:
```mlir
   %cst0 = constant 0 : index
   for %i0 = 0 to %M {
     %a0 = load %A[%cst0, %cst0] : memref<?x?xf32>
   }
```
may vectorize with {permutation_map: (d0) -> (0)} into:
```mlir
   for %i0 = 0 to %0 step 128 {
     %3 = vector_transfer_read %arg0, %c0_0, %c0_0
          {permutation_map: (d0, d1) -> (0)} :
          (memref<?x?xf32>, index, index) -> vector<128xf32>
   }
````
Meaning that vector_transfer_read will be responsible of reading the 0-D slice
`%arg0[%c0, %c0]` into vector<128xf32>. This will require a 1-D vector
broadcast when vector_transfer_read is further lowered.

Additionally, some minor cleanups and refactorings are performed.

One notable thing missing here is the composition with a projection map during
materialization. This is because I could not find an AffineMap composition
that operates on AffineMap directly: everything related to composition seems
to require going through SSAValue and only operates on AffinMap at a distance
via AffineValueMap. I have raised this concern a bunch of times already, the
followup CL will actually do something about it.

In the meantime, the projection is hacked at a minimum to pass verification
and materialiation tests are temporarily incorrect.

PiperOrigin-RevId: 224376828
2019-03-29 14:20:07 -07:00
Uday Bondhugula
9f77faae87 Strided DMA support for DmaStartOp
- add optional stride arguments for DmaStartOp
- add DmaStartOp::verify(), and missing test cases for DMA op's in
  test/IR/memory-ops.mlir.

PiperOrigin-RevId: 224232466
2019-03-29 14:18:37 -07:00
Lei Zhang
b572322859 Add isIntOrIndex() and isIntOrIndexOrFloat() into Type
The checks for `isa<IndexType>() || isa<IntegerType>()` and
`isa<IndexType>() || isa<IntegerType>() || isa<FloatType>()`
are frequently used, so it's useful to have some helper
methods for them.

PiperOrigin-RevId: 224133596
2019-03-29 14:17:38 -07:00
Nicolas Vasilache
b39d1f0bdb [MLIR] Add VectorTransferOps
This CL implements and uses VectorTransferOps in lieu of the former custom
call op. Tests are updated accordingly.

VectorTransferOps come in 2 flavors: VectorTransferReadOp and
VectorTransferWriteOp.

VectorTransferOps can be thought of as a backend-independent
pseudo op/library call that needs to be legalized to MLIR (whiteboxed) before
it can be lowered to backend-dependent IR.

Note that the current implementation does not yet support a real permutation
map. Proper support will come in a followup CL.

VectorTransferReadOp
====================
VectorTransferReadOp performs a blocking read from a scalar memref
location into a super-vector of the same elemental type. This operation is
called 'read' by opposition to 'load' because the super-vector granularity
is generally not representable with a single hardware register. As a
consequence, memory transfers will generally be required when lowering
VectorTransferReadOp. A VectorTransferReadOp is thus a mid-level abstraction
that supports super-vectorization with non-effecting padding for full-tile
only code.

A vector transfer read has semantics similar to a vector load, with additional
support for:
  1. an optional value of the elemental type of the MemRef. This value
     supports non-effecting padding and is inserted in places where the
     vector read exceeds the MemRef bounds. If the value is not specified,
     the access is statically guaranteed to be within bounds;
  2. an attribute of type AffineMap to specify a slice of the original
     MemRef access and its transposition into the super-vector shape. The
     permutation_map is an unbounded AffineMap that must represent a
     permutation from the MemRef dim space projected onto the vector dim
     space.

Example:
```mlir
  %A = alloc(%size1, %size2, %size3, %size4) : memref<?x?x?x?xf32>
  ...
  %val = `ssa-value` : f32
  // let %i, %j, %k, %l be ssa-values of type index
  %v0 = vector_transfer_read %src, %i, %j, %k, %l
        {permutation_map: (d0, d1, d2, d3) -> (d3, d1, d2)} :
          (memref<?x?x?x?xf32>, index, index, index, index) ->
            vector<16x32x64xf32>
  %v1 = vector_transfer_read %src, %i, %j, %k, %l, %val
        {permutation_map: (d0, d1, d2, d3) -> (d3, d1, d2)} :
          (memref<?x?x?x?xf32>, index, index, index, index, f32) ->
            vector<16x32x64xf32>
```

VectorTransferWriteOp
=====================
VectorTransferWriteOp performs a blocking write from a super-vector to
a scalar memref of the same elemental type. This operation is
called 'write' by opposition to 'store' because the super-vector
granularity is generally not representable with a single hardware register. As
a consequence, memory transfers will generally be required when lowering
VectorTransferWriteOp. A VectorTransferWriteOp is thus a mid-level
abstraction that supports super-vectorization with non-effecting padding
for full-tile only code.
A vector transfer write has semantics similar to a vector store, with
additional support for handling out-of-bounds situations.

Example:
```mlir
  %A = alloc(%size1, %size2, %size3, %size4) : memref<?x?x?x?xf32>.
  %val = `ssa-value` : vector<16x32x64xf32>
  // let %i, %j, %k, %l be ssa-values of type index
  vector_transfer_write %val, %src, %i, %j, %k, %l
    {permutation_map: (d0, d1, d2, d3) -> (d3, d1, d2)} :
  (vector<16x32x64xf32>, memref<?x?x?x?xf32>, index, index, index, index)
```
PiperOrigin-RevId: 223873234
2019-03-29 14:15:25 -07:00
Chris Lattner
3f2530cdf5 Split "rewrite" functionality out of Pattern into a new RewritePattern derived
class.  This change is NFC, but allows for new kinds of patterns, specifically
LegalizationPatterns which will be allowed to change the types of things they
rewrite.

PiperOrigin-RevId: 223243783
2019-03-29 14:12:07 -07:00
Lei Zhang
1f5330ac90 Verify CmpIOp's result type to be bool-like
This CL added two new traits, SameOperandsAndResultShape and
ResultsAreBoolLike, and changed CmpIOp to embody these two
traits. As a consequence, CmpIOp's result type now is verified
to be bool-like.

PiperOrigin-RevId: 223208438
2019-03-29 14:11:53 -07:00
Alex Zinenko
a3fb6d0da3 StandardOps: introduce 'select'.
The semantics of 'select' is conventional: return the second operand if the
first operand is true (1 : i1) and the third operand otherwise.  It is
applicable to vectors and tensors element-wise, similarly to LLVM instruction.
This operation is necessary to implement min/max to lower 'for' loops with
complex bounds to CFG functions and to support ternary operations in ML
functions.  It is preferred to first-class min/max because of its simplicity,
e.g. it is not concered with signedness.

PiperOrigin-RevId: 223160860
2019-03-29 14:11:25 -07:00
Chris Lattner
721a30d6a0 Tidy up the replaceOp hooks in PatternMatch, generalizing them to support any
number of result ops.  Among other things, this results in shorter names

PiperOrigin-RevId: 222685039
2019-03-29 14:09:28 -07:00
River Riddle
58cd315a68 Remove unnecessary include from StandardOps.cpp.
PiperOrigin-RevId: 222316745
2019-03-29 14:05:34 -07:00
Uday Bondhugula
fff1efbaf5 Updates to transformation/analysis passes/utilities. Update DMA generation pass
and getMemRefRegion() to work with specified loop depths; add support for
outgoing DMAs, store op's.

- add support for getMemRefRegion symbolic in outer loops - hence support for
  DMAs symbolic in outer surrounding loops.

- add DMA generation support for outgoing DMAs (store op's to lower memory
  space); extend getMemoryRegion to store op's. -memref-bound-check now works
  with store op's as well.

- fix dma-generate (references to the old memref in the dma_start op were also
  being replaced with the new buffer); we need replace all memref uses to work
  only on a subset of the uses - add a new optional argument for
  replaceAllMemRefUsesWith. update replaceAllMemRefUsesWith to take an optional
  'operation' argument to serve as a filter - if provided, only those uses that
  are dominated by the filter are replaced.

- Add missing print for attributes for dma_start, dma_wait op's.

- update the FlatAffineConstraints API

PiperOrigin-RevId: 221889223
2019-03-29 14:00:51 -07:00
Jacques Pienaar
711047c0cd Add Type to int/float attributes.
* Optionally attach the type of integer and floating point attributes to the attributes, this allows restricting a int/float to specific width.
  - Currently this allows suffixing int/float constant with type [this might be revised in future].
  - Default to i64 and f32 if not specified.
* For index types the APInt width used is 64.
* Change callers to request a specific attribute type.
* Store iN type with APInt of width N.
* This change does not handle the folding of constants of different types (e.g., doing int type promotions to support constant folding i3 and i32), and instead restricts the constant folding to only operate on the same types.

PiperOrigin-RevId: 221722699
2019-03-29 13:59:23 -07:00
Jacques Pienaar
25e6b541cd Switch IntegerAttr to use APInt.
Change the storage type to APInt from int64_t for IntegerAttr (following the change to APFloat storage in FloatAttr). Effectively a direct change from int64_t to 64-bit APInt throughout (the bitwidth hardcoded). This change also adds a getInt convenience method to IntegerAttr and replaces previous getValue calls with getInt calls.

While this changes updates the storage type, it does not update all constant folding calls.

PiperOrigin-RevId: 221082788
2019-03-29 13:55:08 -07:00
Chris Lattner
86a5323f04 - Simplify PatternMatch to *require* static benefits at pattern construction
time.  The "Fast and Flexible Instruction Selection With Constraints" paper
  from CC2018 makes a credible argument that dynamic costs aren't actually
  necessary/important, and we are not using them.

- Check in my "MLIR Generic DAG Rewriter Infrastructure" design doc into the
  source tree.

PiperOrigin-RevId: 221017546
2019-03-29 13:54:38 -07:00
Uday Bondhugula
e0623d4b86 Automatic DMA generation for simple cases.
- constant bounded memory regions, static shapes, no handling of
  overlapping/duplicate regions (through union) for now; also only, load memory
  op's.
- add build methods for DmaStartOp, DmaWaitOp.
- move getMemoryRegion() into Analysis/Utils and expose it.
- fix addIndexSet, getMemoryRegion() post switch to exclusive upper bounds;
  update test cases for memref-bound-check and memref-dependence-check for
  exclusive bounds (missed in a previous CL)

PiperOrigin-RevId: 220729810
2019-03-29 13:53:14 -07:00
Alex Zinenko
ac2a655e87 Enable arithmetics for index types.
Arithmetic and comparison instructions are necessary to implement, e.g.,
control flow when lowering MLFunctions to CFGFunctions.  (While it is possible
to replace some of the arithmetics by affine_apply instructions for loop
bounds, it is still necessary for loop bounds checking, steps, if-conditions,
non-trivial memref subscripts, etc.)  Furthermore, working with indirect
accesses in, e.g., lookup tables for large embeddings, may require operating on
tensors of indexes.  For example, the equivalents to C code "LUT[Index[i]]" or
"ResultIndex[i] = i + j" where i, j are loop induction variables require the
arithmetics on indices as well as the possibility to operate on tensors
thereof.  Allow arithmetic and comparison operations to apply to index types by
declaring them integer-like.  Allow tensors whose element type is index for
indirection purposes.

The absence of vectors with "index" element type is explicitly tested, but the
only justification for this restriction in the CL introducing the test is
"because we don't need them".  Do NOT enable vectors of index types, although
it makes vector and tensor types inconsistent with respect to allowed element
types.

PiperOrigin-RevId: 220614055
2019-03-29 13:51:19 -07:00
Alex Zinenko
3a38a5d0d6 Introduce integer comparison operation.
This binary operation is applicable to integers, vectors and tensors thereof
similarly to binary arithmetic operations.  The operand types must match
exactly, and the shape of the result type is the same as that of the operands.
The element type of the result is always i1.  The kind of the comparison is
defined by the "predicate" integer attribute.  This attribute requests one of:
- equals to;
- not equals to;
- signed less than;
- signed less than or equals;
- signed greater than;
- signed greater than or equals;
- unsigned less than;
- unsigned less than or equals;
- unsigned greater than;
- unsigned greater than or equals.
Since integer values themselves do not have a sign, the comparison operator
specifies whether to use signed or unsigned comparison logic, i.e. whether to
interpret values where the foremost bit is set as negatives expressed as two's
complements or as positive values.  For non-scalar operands, pairwise
per-element comparison is performed.  Comparison operators on scalars are
necessary to implement basic control flow with conditional branches.

PiperOrigin-RevId: 220613566
2019-03-29 13:50:49 -07:00
River Riddle
4c465a181d Implement value type abstraction for types.
This is done by changing Type to be a POD interface around an underlying pointer storage and adding in-class support for isa/dyn_cast/cast.

PiperOrigin-RevId: 219372163
2019-03-29 13:45:54 -07:00
Lei Zhang
5ffb211bff Rename mlir::match to mlir::matchPattern and add m_Op()
- We already have Pattern::match(). Using mlir::match() in Pattern::match()
  confuses the compiler.
- Created m_Op() to avoid using detailed matcher implementation in
  StandardOps.cpp.

PiperOrigin-RevId: 219328823
2019-03-29 13:44:47 -07:00
Uday Bondhugula
bdfd6193b8 Add getMemRefType() accessors to LoadOp/StoreOp.
- There are several places where we are casting the type of the memref obtained
  from the load/store op to a memref type, and this will become even more
  common (some upcoming CLs this week). Add a getMemRefType and use it at
  several places where the cast was being used.

PiperOrigin-RevId: 219164326
2019-03-29 13:43:58 -07:00
Lei Zhang
582b0761c6 Use matcher sugars for cannonicalization pattern matching
- Added a mechanism for specifying pattern matching more concisely like LLVM.
- Added support for canonicalization of addi/muli over vector/tensor splat
- Added ValueType to Attribute class hierarchy
- Allowed creating constant splat

PiperOrigin-RevId: 219149621
2019-03-29 13:43:44 -07:00
Lei Zhang
60b5184c8b Canonicalize muli(x, 1) into x
PiperOrigin-RevId: 218885877
2019-03-29 13:42:01 -07:00
Alex Zinenko
87c5145a5d Perform the MemRef layout map dimensionality check in the Parser.
This check was being performed in AllocOp::verify.  However it is not specific
to AllocOp and should apply to all MemRef type declarations.  At the same time,
the unique *Type factory functions in MLIRContext do not have access to
location information necessary to properly emit diagnostics.  Emit the error in
Parser where the location information is available.  Keep the error emission in
AllocOp for the cases of programmatically-constructed, e.g. through Builders,
IR with a note.  Once we decided on the diagnostic infrastructure in type
construction system, the type-related checks should be removed from specific
Ops.

Correct several parser test cases that have been using affine maps of
mismatching dimensionality.

This CL prepares for an upcoming change that will drop trivial identity affine
map compositions during MemRefType construction.  In that case, the
dimensionality mismatch error must be emitted before dropping the identity map,
i.e. during the type construction at the latest and before "verify" being
called.

PiperOrigin-RevId: 218844127
2019-03-29 13:41:33 -07:00
Chris Lattner
7de0da9594 Refactor all of the canonicalization patterns out of the Canonicalize pass, and
make operations provide a list of canonicalizations that can be applied to
them.  This allows canonicalization to be general to any IR definition.

As part of this, sink PatternMatch.h/cpp down to the IR library to fix a
layering problem.

PiperOrigin-RevId: 218773981
2019-03-29 13:39:49 -07:00
River Riddle
792d1c25e4 Implement value type abstraction for attributes.
This is done by changing Attribute to be a POD interface around an underlying pointer storage and adding in-class support for isa/dyn_cast/cast.

PiperOrigin-RevId: 218764173
2019-03-29 13:39:19 -07:00
Alex Zinenko
e8d254b909 Rename shape_cast to tensor_cast.
"shape_cast" only applies to tensors, and there are other operations that
actually affect shape, for example "reshape".  Rename "shape_cast" to
"tensor_cast" in both the code and the documentation.

PiperOrigin-RevId: 218528122
2019-03-29 13:37:41 -07:00
Chris Lattner
50cc57e25a Random cleanups:
- Change AllocOp to have a getType() that always returns a MemRefType, since
   that is what it requires.
 - Rename StandardOps/StandardOpRegistration.cpp ->
   StandardOps/OpRegistration.cpp to align with other op sets.
 - Add AffineMap::getContext() helper and use it in the asmprinter.

PiperOrigin-RevId: 218205527
2019-03-29 13:35:19 -07:00
Chris Lattner
b2f93b27ee introduce a memref_cast operation, refactoring common code between it and
shape_cast into a common CastOp class.

PiperOrigin-RevId: 218175818
2019-03-29 13:35:06 -07:00
Chris Lattner
9eedf6adb1 Replace the "OperationSet" abstraction with a new Dialect abstraction. This is
a step forward because now every AbstractOperation knows which Dialect it is
associated with, enabling things in the future like "constant folding
hooks" which will be important for layering.  This is also a bit nicer on
the registration side of things.

PiperOrigin-RevId: 218104230
2019-03-29 13:34:37 -07:00
Uday Bondhugula
18e666702c Generalize / improve DMA transfer overlap; nested and multiple DMA support; resolve
multiple TODOs.

- replace the fake test pass (that worked on just the first loop in the
  MLFunction) to perform DMA pipelining on all suitable loops.
- nested DMAs work now (DMAs in an outer loop, more DMAs in nested inner loops)
- fix bugs / assumptions: correctly copy memory space and elemental type of source
  memref for double buffering.
- correctly identify matching start/finish statements, handle multiple DMAs per
  loop.
- introduce dominates/properlyDominates utitilies for MLFunction statements.
- move checkDominancePreservationOnShifts to LoopAnalysis.h; rename it
  getShiftValidity
- refactor getContainingStmtPos -> findAncestorStmtInBlock - move into
  Analysis/Utils.h; has two users.
- other improvements / cleanup for related API/utilities
- add size argument to dma_wait - for nested DMAs or in general, it makes it
  easy to obtain the size to use when lowering the dma_wait since we wouldn't
  want to identify the matching dma_start, and more importantly, in general/in the
  future, there may not always be a dma_start dominating the dma_wait.
- add debug information in the pass

PiperOrigin-RevId: 217734892
2019-03-29 13:32:28 -07:00
Chris Lattner
7e7157fd1d Various improvements to pattern matching and other infra:
- Make it so OpPointer implicitly converts to SSAValue* when the underlying op
   has a single value.  This eliminates a lot more ->getResult() calls and makes
   the behavior more LLVM-like
 - Fill out PatternBenefit to be typed instead of just a typedef for int with
   magic numbers.
 - Simplify various code due to these changes.

PiperOrigin-RevId: 217020717
2019-03-29 13:29:49 -07:00
Uday Bondhugula
0ceda12cc5 Missed change - remove 1-d tag memref restriction while parsing DmaStartOp.
Fixing oversight from cl/216429885.

PiperOrigin-RevId: 216768516
2019-03-29 13:28:40 -07:00
Jacques Pienaar
764fd035b0 Split BuiltinOps out of StandardOps.
* Move Return, Constant and AffineApply out into BuiltinOps;
* BuiltinOps are always registered, while StandardOps follow the same dynamic registration;
* Kept isValidX in MLValue as we don't have a verify on AffineMap so need to keep it callable from Parser (I wanted to move it to be called in verify instead);

PiperOrigin-RevId: 216592527
2019-03-29 13:28:12 -07:00