Commit Graph

48 Commits

Author SHA1 Message Date
Christopher Di Bella 0082764605 Revert "Add workaround for false positive in -Wfree-nonheap-object"
This reverts commit 499571ea83.
2021-07-21 21:30:17 +00:00
River Riddle 6304c0836a [mlir] Store the flag for dynamic operand storage in the low bits
It is currently stored in the high bits, which is disallowed on certain
platforms (e.g. android). This revision switches the representation to use
the low bits instead, fixing crashes/breakages on those platforms.

Differential Revision: https://reviews.llvm.org/D101969
2021-05-06 12:45:35 -07:00
David Blaikie 499571ea83 Add workaround for false positive in -Wfree-nonheap-object 2021-04-03 14:03:43 -07:00
River Riddle a776ecb6c2 [mlir][IR] Add an Operation::eraseOperands that supports batch erasure
This method allows for removing multiple disjoint operands at once, reducing the need to erase operands individually (which results in shifting the operand list).

Differential Revision: https://reviews.llvm.org/D98290
2021-03-09 15:07:53 -08:00
River Riddle 2f37cdd569 [mlir][IR][NFC] Move a majority of the builtin attributes to ODS
Now that attributes can be generated using ODS, we can move the builtin attributes as well. This revision removes a majority of the builtin attributes with a few left for followup revisions. The attributes moved to ODS in this revision are: AffineMapAttr, ArrayAttr, DictionaryAttr, IntegerSetAttr, StringAttr, SymbolRefAttr, TypeAttr, and UnitAttr.

Differential Revision: https://reviews.llvm.org/D97591
2021-03-04 13:04:06 -08:00
River Riddle 3dfa86149e [mlir][IR] Refactor the internal implementation of Value
The current implementation of Value involves a pointer int pair with several different kinds of owners, i.e. BlockArgumentImpl*, Operation *, TrailingOpResult*. This design arose from the desire to save memory overhead for operations that have a very small number of results (generally 0-2). There are, unfortunately, many problematic aspects of the current implementation that make Values difficult to work with or just inefficient.

Operation result types are stored as a separate array on the Operation. This is very inefficient for many reasons: we use TupleType for multiple results, which can lead to huge amounts of memory usage if multi-result operations change types frequently(they do). It also means that simple methods like Value::getType/Value::setType now require complex logic to get to the desired type.

Value only has one pointer bit free, severely limiting the ability to use it in things like PointerUnion/PointerIntPair. Given that we store the kind of a Value along with the "owner" pointer, we only leave one bit free for users of Value. This creates situations where we end up nesting PointerUnions to be able to use Value in one.

As noted above, most of the methods in Value need to branch on at least 3 different cases which is both inefficient, possibly error prone, and verbose. The current storage of results also creates problems for utilities like ValueRange/TypeRange, which want to efficiently store base pointers to ranges (of which Operation* isn't really useful as one).

This revision greatly simplifies the implementation of Value by the introduction of a new ValueImpl class. This class contains all of the state shared between all of the various derived value classes; i.e. the use list, the type, and the kind. This shared implementation class provides several large benefits:

* Most of the methods on value are now branchless, and often one-liners.

* The "kind" of the value is now stored in ValueImpl instead of Value
This frees up all of Value's pointer bits, allowing for users to take full advantage of PointerUnion/PointerIntPair/etc. It also allows for storing more operation results as "inline", 6 now instead of 2, freeing up 1 word per new inline result.

* Operation result types are now stored in the result, instead of a side array
This drops the size of zero-result operations by 1 word. It also removes the memory crushing use of TupleType for operations results (which could lead up to hundreds of megabytes of "dead" TupleTypes in the context). This also allowed restructured ValueRange, making it simpler and one word smaller.

This revision does come with two conceptual downsides:
* Operation::getResultTypes no longer returns an ArrayRef<Type>
This conceptually makes some usages slower, as the iterator increment is slightly more complex.
* OpResult::getOwner is slightly more expensive, as it now requires a little bit of arithmetic

From profiling, neither of the conceptual downsides have resulted in any perceivable hit to performance. Given the advantages of the new design, most compiles are slightly faster.

Differential Revision: https://reviews.llvm.org/D97804
2021-03-03 14:33:37 -08:00
River Riddle fc5cf50e89 [mlir] Remove the MutableDictionaryAttr class
This class used to serve a few useful purposes:
* Allowed containing a null DictionaryAttr
* Provided some simple mutable API around a DictionaryAttr

The first of which is no longer an issue now that there is much better caching support for attributes in general, and a cache in the context for empty dictionaries. The second results in more trouble than it's worth because it mutates the internal dictionary on every action, leading to a potentially large number of dictionary copies. NamedAttrList is a much better alternative for the second use case, and should be modified as needed to better fit it's usage as a DictionaryAttrBuilder.

Differential Revision: https://reviews.llvm.org/D93442
2020-12-17 17:18:42 -08:00
River Riddle 47364f95e8 [mlir][IR] Move the storage for results to before the Operation instead of after.
Trailing objects are really nice for storing additional data inline with the main class, and is something that we heavily take advantage of for Operation(and many other classes). To get the address of the inline data you need to compute the address by doing some pointer arithmetic taking into account any objects stored before the object you want to access. Most classes keep the count of the number of objects, so this is relatively cheap to compute. This is not the case for results though, which have two different types(inline and trailing) that are not necessarily as cheap to compute as the count for other objects. This revision moves the storage for results to before the operation and stores them in reverse order. This allows for getting results to still be very fast given that they are never iterated directly in order, and also greatly improves the speed when accessing the other trailing objects of an operation(operands/regions/blocks/etc).

This reduced compile time when compiling a decently sized mlir module by about ~400ms, or 2.17s -> 1.76s.

Differential Revision: https://reviews.llvm.org/D92687
2020-12-04 21:01:42 -08:00
River Riddle 09f7a55fad [mlir][Types][NFC] Move all of the builtin Type classes to BuiltinTypes.h
This is part of a larger refactoring the better congregates the builtin structures under the BuiltinDialect. This also removes the problematic "standard" naming that clashes with the "standard" dialect, which is not defined within IR/. A temporary forward is placed in StandardTypes.h to allow time for downstream users to replaced references.

Differential Revision: https://reviews.llvm.org/D92435
2020-12-03 18:02:10 -08:00
Rahul Joshi c298824f9c [MLIR] Check for duplicate entries in attribute dictionary during custom parsing
- Verify that attributes parsed using a custom parser do not have duplicates.
- If there are duplicated in the attribute dictionary in the input, they get caught during the
  dictionary parsing.
- This check verifies that there is no duplication between the parsed dictionary and any
  attributes that might be added by the custom parser (or when the custom parsing code
  adds duplicate attributes).
- Fixes https://bugs.llvm.org/show_bug.cgi?id=48025

Differential Revision: https://reviews.llvm.org/D90502
2020-11-03 16:40:46 -08:00
Alex Zinenko 03e6f40cdb [mlir] Do not print back 0 alignment in LLVM dialect 'alloca' op
The alignment attribute in the 'alloca' op treats the '0' value as 'unset'.
When parsing the custom form of the 'alloca' op, ignore the alignment attribute
with if its value is '0' instead of actually creating it and producing a
slightly different textually yet equivalent semantically form in the output.

Reviewed By: rriddle

Differential Revision: https://reviews.llvm.org/D90179
2020-10-26 23:19:20 +01:00
Rahul Joshi a6ae695017 [MLIR][NFC] Adopt use of BlockRange in place of ArrayRef<Block *>
- Use BlockRange in ODS generated builders as well as other places throughout the code

Differential Revision: https://reviews.llvm.org/D87955
2020-09-23 09:21:54 -07:00
Rahul Joshi 8893d0816c [MLIR] Change Operation::create() methods to use Value/Type/Block ranges.
- Introduce a new BlockRange class to represent range of blocks (constructible from
  an ArrayRef<Block *> or a SuccessorRange);
- Change Operation::create() methods to use TypeRange for result types, ValueRange for
  operands and BlockRange for successors.

Differential Revision: https://reviews.llvm.org/D86985
2020-09-08 14:19:05 -07:00
River Riddle eaeadce9bd [mlir][OpFormatGen] Add initial support for regions in the custom op assembly format
This adds some initial support for regions and does not support formatting the specific arguments of a region. For now this can be achieved by using a custom directive that formats the arguments and then parses the region.

Differential Revision: https://reviews.llvm.org/D86760
2020-08-31 13:26:24 -07:00
Rahul Joshi 1d6a724aa1 [MLIR] Change FunctionType::get() and TupleType::get() to use TypeRange
- Moved TypeRange into its own header/cpp file, and add hashing support.
- Change FunctionType::get() and TupleType::get() to use TypeRange

Differential Revision: https://reviews.llvm.org/D85075
2020-08-04 12:43:40 -07:00
Nicolas Vasilache 79f059c4ac [mlir] NFC - Fix OperationSupport.cpp::findNamedAttr
Summary:
When NamedAttrList::get is called against a StringRef and the
entry is not present, the Identifier::operator== crashes.
Interestingly there seems to be no use of the NamedAttrList::get(StringRef) in
the codebase so far. A subsequent commit will introduce such a use.

Differential Revision: https://reviews.llvm.org/D80089
2020-05-18 09:36:00 -04:00
Jacques Pienaar 5eae715a31 [mlir] Add NamedAttrList
This is a wrapper around vector of NamedAttributes that keeps track of whether sorted and does some minimal effort to remain sorted (doing more, e.g., appending attributes in sorted order, could be done in follow up). It contains whether sorted and if a DictionaryAttr is queried, it caches the returned DictionaryAttr along with whether sorted.

Change MutableDictionaryAttr to always return a non-null Attribute even when empty (reserve null cases for errors). To this end change the getter to take a context as input so that the empty DictionaryAttr could be queried. Also create one instance of the empty dictionary attribute that could be reused without needing to lock context etc.

Update infer type op interface to use DictionaryAttr and use NamedAttrList to avoid incurring multiple conversion costs.

Fix bug in sorting helper function.

Differential Revision: https://reviews.llvm.org/D79463
2020-05-07 12:33:36 -07:00
River Riddle 469c02d058 [mlir] Add support for merging identical blocks during canonicalization
This revision adds support for merging identical blocks, or those with the same operations that branch to the same successors. Operands that mismatch between the different blocks are replaced with new block arguments added to the merged block.

Differential Revision: https://reviews.llvm.org/D79134
2020-05-04 19:56:46 -07:00
River Riddle 0752d98ccf [mlir] Simplify BranchOpInterface by using MutableOperandRange
This range allows for performing many different operations on successor operands, including erasing/adding/setting. This removes the need for the explicit canEraseSuccessorOperand and eraseSuccessorOperand methods.

Differential Revision: https://reviews.llvm.org/D79077
2020-04-29 16:48:15 -07:00
River Riddle df00e466da [mlir] Move the operation equivalence out of CSE and into OperationSupport
This provides a general hash and comparison for checking if two operations are equivalent. This revision also optimizes the handling of result types to take advantage of how result types are stored on the operation.

Differential Revision: https://reviews.llvm.org/D79029
2020-04-29 16:48:15 -07:00
River Riddle 108abd2f2e [mlir] Add a new MutableOperandRange class for adding/remove operands
This class allows for mutating an operand range in-place, and provides vector like API for adding/erasing/setting. ODS now uses this class to generate mutable wrappers for named operands, with the name `MutableOperandRange <operand-name>Mutable()`

Differential Revision: https://reviews.llvm.org/D78892
2020-04-29 16:48:14 -07:00
River Riddle 4dfd1b5fcb [mlir] Optimize operand storage such that all operations can have resizable operand lists
This revision refactors the structure of the operand storage such that there is no additional memory cost for resizable operand lists until it is required. This is done by using two different internal representations for the operand storage:
* One using trailing operands
* One using a dynamically allocated std::vector<OpOperand>

This allows for removing the resizable operand list bit, and will free up APIs from needing to workaround non-resizable operand lists.

Differential Revision: https://reviews.llvm.org/D78875
2020-04-26 21:34:01 -07:00
River Riddle 8da0f85ea5 [mlir] Optimize the allocation of resizable operand lists
This revision optimizes resizable operand lists by allocating them in the same location as the trailing operands. This has numerous benefits:
* If the operation has at least one operand at construction time, there is 0 additional memory overhead to the resizable storage.
* There is less pointer arithmetic necessary as the resizable storage is now only used when the operands are dynamically allocated.

Differential Revision: https://reviews.llvm.org/D78854
2020-04-26 21:34:01 -07:00
River Riddle 48e9ef4320 [mlir] Give each OpResult its own use list
This revision removes the multi use-list to ensure that each result gets its own. This decision was made by doing some extensive benchmarking of programs that actually use multiple results. This results in a size increase of 1-word per result >1, but the common case of 1-result remains unaffected. A side benefit is that 0-result operations now shrink by 1-word.

Differential Revision: https://reviews.llvm.org/D78701
2020-04-23 16:28:55 -07:00
River Riddle b87531ca68 [mlir] Fix getTypes() support for result ranges. 2020-04-20 17:18:42 -07:00
River Riddle 204c3b5516 [llvm][STLExtras] Move various iterator/range utilities from MLIR to LLVM
This revision moves the various range utilities present in MLIR to LLVM to enable greater reuse. This revision moves the following utilities:

* indexed_accessor_*
This is set of utility iterator/range base classes that allow for building a range class where the iterators are represented by an object+index pair.

* make_second_range
Given a range of pairs, returns a range iterating over the `second` elements.

* hasSingleElement
Returns if the given range has 1 element. size() == 1 checks end up being very common, but size() is not always O(1) (e.g., ilist). This method provides O(1) checks for those cases.

Differential Revision: https://reviews.llvm.org/D78064
2020-04-14 15:14:40 -07:00
River Riddle cb1777127c [mlir] Remove successor operands from the Operation class
Summary:
This revision removes all of the functionality related to successor operands on the core Operation class. This greatly simplifies a lot of handling of operands, as well as successors. For example, DialectConversion no longer needs a special "matchAndRewrite" for branching terminator operations.(Note, the existing method was also broken for operations with variadic successors!!)

This also enables terminator operations to define their own relationships with successor arguments, instead of the hardcoded "pass-through" behavior that exists today.

Differential Revision: https://reviews.llvm.org/D75318
2020-03-05 12:53:02 -08:00
River Riddle 988249a506 [mlir] Refactor a few users to no longer rely on the successor operand API of Operation.
The existing API for successor operands on operations is in the process of being removed. This revision simplifies a later one that completely removes the existing API.

Differential Revision: https://reviews.llvm.org/D75316
2020-03-05 12:51:59 -08:00
River Riddle 621d7cca37 [mlir] Add a new BranchOpInterface to allow for opaquely interfacing with branching terminator operations.
This interface contains the necessary components to provide the same builtin behavior that terminators have. This will be used in future revisions to remove many of the hardcoded constraints placed on successors and successor operands. The interface initially contains three methods:

```c++
// Return a set of values corresponding to the operands for successor 'index', or None if the operands do not correspond to materialized values.
Optional<OperandRange> getSuccessorOperands(unsigned index);

// Return true if this terminator can have it's successor operands erased.
bool canEraseSuccessorOperand();

// Erase the operand of a successor. This is only valid to call if 'canEraseSuccessorOperand' returns true.
void eraseSuccessorOperand(unsigned succIdx, unsigned opIdx);
```

Differential Revision: https://reviews.llvm.org/D75314
2020-03-05 12:50:35 -08:00
River Riddle 94a4ca4bf3 [mlir] Add a TypeRange class that functions similar to ValueRange.
Summary: This class wraps around the various different ways to construct a range of Type, without forcing the materialization of that range into a contiguous vector.

Differential Revision: https://reviews.llvm.org/D74646
2020-02-18 11:37:24 -08:00
River Riddle aff4ed7326 [mlir][NFC] Update Operation::getResultTypes to use ArrayRef<Type> instead of iterator_range.
Summary: The new internal representation of operation results now allows for accessing the result types to be more efficient. Changing the API to ArrayRef is more efficient and removes the need to explicitly materialize vectors in several places.

Differential Revision: https://reviews.llvm.org/D73429
2020-01-27 19:57:48 -08:00
Mehdi Amini 308571074c Mass update the MLIR license header to mention "Part of the LLVM project"
This is an artifact from merging MLIR into LLVM, the file headers are
now aligned with the rest of the project.
2020-01-26 03:58:30 +00:00
River Riddle 0d9ca98c1a [mlir] Fix indexed_accessor_range to properly forward the derived class.
Summary: This fixes the return value of helper methods on the base range class.

Reviewed By: jpienaar

Differential Revision: https://reviews.llvm.org/D72127
2020-01-03 13:30:18 -08:00
River Riddle fd01d8626c [mlir] Rewrite the internal representation of OpResult to be optimized for memory.
Summary:
This changes the implementation of OpResult to have some of the results be represented inline in Value, via a pointer int pair of Operation*+result number, and the rest being trailing objects on the main operation. The full details of the new representation is detailed in the proposal here:
https://groups.google.com/a/tensorflow.org/g/mlir/c/XXzzKhqqF_0/m/v6bKb08WCgAJ

The only difference between here and the above proposal is that we only steal 2-bits for the Value kind instead of 3. This means that we can only fit 2-results inline instead of 6. This allows for other users to steal the final bit for PointerUnion/etc. If necessary, we can always steal this bit back in the future to save more space if 3-6 results are common enough.

Reviewed By: jpienaar

Differential Revision: https://reviews.llvm.org/D72020
2020-01-02 14:40:09 -08:00
River Riddle ab46543ceb Resubmit: ReImplement the Value classes as value-typed objects wrapping an internal pointer storage.
This will enable future commits to reimplement the internal implementation of OpResult without needing to change all of the existing users. This is part of a chain of commits optimizing the size of operation results.

PiperOrigin-RevId: 286930047
2019-12-23 16:05:05 -08:00
MLIR Team 268365ab01 Automated rollback of commit f603a50109
PiperOrigin-RevId: 286924059
2019-12-23 15:54:44 -08:00
River Riddle f603a50109 ReImplement the Value classes as value-typed objects wrapping an internal pointer storage.
This will enable future commits to reimplement the internal implementation of OpResult without needing to change all of the existing users. This is part of a chain of commits optimizing the size of operation results.

PiperOrigin-RevId: 286919966
2019-12-23 15:44:00 -08:00
Mehdi Amini 56222a0694 Adjust License.txt file to use the LLVM license
PiperOrigin-RevId: 286906740
2019-12-23 15:33:37 -08:00
River Riddle 35807bc4c5 NFC: Introduce new ValuePtr/ValueRef typedefs to simplify the transition to Value being value-typed.
This is an initial step to refactoring the representation of OpResult as proposed in: https://groups.google.com/a/tensorflow.org/g/mlir/c/XXzzKhqqF_0/m/v6bKb08WCgAJ

This change will make it much simpler to incrementally transition all of the existing code to use value-typed semantics.

PiperOrigin-RevId: 286844725
2019-12-22 22:00:23 -08:00
River Riddle 9ed22ae5b8 Refactor the various operand/result/type iterators to use indexed_accessor_range.
This has several benefits:
* The implementation is much cleaner and more efficient.
* The ranges now have support for many useful operations: operator[], slice, drop_front, size, etc.
* Value ranges can now directly query a range for their types via 'getTypes()': e.g:
   void foo(Operation::operand_range operands) {
     auto operandTypes = operands.getTypes();
   }

PiperOrigin-RevId: 284834912
2019-12-10 13:21:22 -08:00
Uday Bondhugula a63f6e0bf9 Replace spurious SmallVector constructions with ValueRange
Signed-off-by: Uday Bondhugula <uday@polymagelabs.com>

Closes tensorflow/mlir#305

COPYBARA_INTEGRATE_REVIEW=https://github.com/tensorflow/mlir/pull/305 from bondhugula:value_range 21d1fae73f549e3c8e72b60876eff1b864cea39c
PiperOrigin-RevId: 284541027
2019-12-09 06:26:33 -08:00
River Riddle d6ee6a0310 Update the builder API to take ValueRange instead of ArrayRef<Value *>
This allows for users to provide operand_range and result_range in builder.create<> calls, instead of requiring an explicit copy into a separate data structure like SmallVector/std::vector.

PiperOrigin-RevId: 284360710
2019-12-07 10:35:41 -08:00
River Riddle 2f59f76876 NFC: Remove the explicit context from Operation::create and OperationState.
The context can easily be recovered from the Location in these situations.

PiperOrigin-RevId: 265578574
2019-08-26 17:34:48 -07:00
Alex Zinenko 0b468b0101 gpu::LaunchOp: canonicalize away constant kernel arguments
The GPU Launch operation may take constants as arguments, in particular
affine-to-GPU mapping pass automatically forwards potentially constant lower
bounds of loops into the kernel.  Define a canonicalization pattern for
LaunchOp that recreates the constants inside the kernel region instead of
accepting them as kernel arguments.  This is currently restricted to standard
constants but may be extended to other constant operations.

Also fix an off-by-one indexing bug in OperandStorage::eraseOperand.

PiperOrigin-RevId: 256035437
2019-07-01 17:03:03 -07:00
River Riddle 48d6cf1ced NFC: Remove the 'context' parameter from OperationState.
Now that Locations are Attributes they contain a direct reference to the MLIRContext, i.e. the context can be directly accessed from the given location instead of being explicitly passed in.

PiperOrigin-RevId: 254568329
2019-06-22 13:05:10 -07:00
River Riddle 213b8d4d3b Rename InstOperand to OpOperand.
PiperOrigin-RevId: 240814651
2019-03-29 17:50:41 -07:00
River Riddle 9ffdc930c0 Rename the Instruction class to Operation. This just renames the class, usages of Instruction will still refer to a typedef in the interim.
This is step 1/N to renaming Instruction to Operation.

PiperOrigin-RevId: 240431520
2019-03-29 17:42:50 -07:00
Alex Zinenko a7215a9032 Allow creating standalone Regions
Currently, regions can only be constructed by passing in a `Function` or an
`Instruction` pointer referencing the parent object, unlike `Function`s or
`Instruction`s themselves that can be created without a parent.  It leads to a
rather complex flow in operation construction where one has to create the
operation first before being able to work with its regions.  It may be
necessary to work with the regions before the operation is created.  In
particular, in `build` and `parse` functions that are executed _before_ the
operation is created in cases where boilerplate region manipulation is required
(for example, inserting the hypothetical default terminator in affine regions).
Allow creating standalone regions.  Such regions are meant to own a list of
blocks and transfer them to other regions on demand.

Each instruction stores a fixed number of regions as trailing objects and has
ownership of them.  This decreases the size of the Instruction object for the
common case of instructions without regions.  Keep this behavior intact.  To
allow some flexibility in construction, make OperationState store an owning
vector of regions.  When the Builder creates an Instruction from
OperationState, the bodies of the regions are transferred into the
instruction-owned regions to minimize copying.  Thus, it becomes possible to
fill standalone regions with blocks and move them to an operation when it is
constructed, or move blocks from a region to an operation region, e.g., for
inlining.

PiperOrigin-RevId: 240368183
2019-03-29 17:40:59 -07:00