95 Commits

Author SHA1 Message Date
Matthias Springer
f18c3e4e73
[mlir][Transforms] Dialect Conversion: Simplify materialization fn result type (#113031)
This commit simplifies the result type of materialization functions.

Previously: `std::optional<Value>`
Now: `Value`

The previous implementation allowed 3 possible return values:
- Non-null value: The materialization function produced a valid
materialization.
- `std::nullopt`: The materialization function failed, but another
materialization can be attempted.
- `Value()`: The materialization failed and so should the dialect
conversion. (Previously: Dialect conversion can roll back.)

This commit removes the last variant. It is not particularly useful
because the dialect conversion will fail anyway if all other
materialization functions produced `std::nullopt`.

Furthermore, in contrast to type conversions, at least one
materialization callback is expected to succeed. In case of a failing
type conversion, the current dialect conversion can roll back and try a
different pattern. This also used to be the case for materializations,
but that functionality was removed with #107109: failed materializations
can no longer trigger a rollback. (They can just make the entire dialect
conversion fail without rollback.) With this in mind, it is even less
useful to have an additional error state for materialization functions.

This commit is in preparation of merging the 1:1 and 1:N type
converters. Target materializations will have to return multiple values
instead of a single one. With this commit, we can keep the API simple:
`SmallVector<Value>` instead of `std::optional<SmallVector<Value>>`.

Note for LLVM integration: All 1:1 materializations should return
`Value` instead of `std::optional<Value>`. Instead of `std::nullopt`
return `Value()`.
2024-10-23 07:29:17 -07:00
Matthias Springer
6937dbbe51
[mlir][memref] Fix alloca lowering with 0 dimensions (#111119)
The `memref.alloca` lowering computed the allocation size incorrectly
when there were 0 dimensions.

Previously:
```
memref.alloca() : memref<10x0x2xf32>
--> llvm.alloca 20xf32
```

Now:
```
memref.alloca() : memref<10x0x2xf32>
--> llvm.alloca 0xf32
```

From the `llvm.alloca` documentation:
```
Allocating zero bytes is legal, but the returned pointer may not be unique.
```
2024-10-04 17:32:31 +02:00
Sergey Kozub
3f9cabae00
[MLIR] Add f8E8M0FNU type (#111028)
This PR adds `f8E8M0FNU` type to MLIR.

`f8E8M0FNU` type is proposed in [OpenCompute MX
Specification](https://www.opencompute.org/documents/ocp-microscaling-formats-mx-v1-0-spec-final-pdf).
It defines a 8-bit floating point number with bit layout S0E8M0. Unlike
IEEE-754 types, there are no infinity, denormals, zeros or negative
values.

```c
f8E8M0FNU
- Exponent bias: 127
- Maximum stored exponent value: 254 (binary 1111'1110)
- Maximum unbiased exponent value: 254 - 127 = 127
- Minimum stored exponent value: 0 (binary 0000'0000)
- Minimum unbiased exponent value: 0 − 127 = -127
- Doesn't have zero
- Doesn't have infinity
- NaN is encoded as binary 1111'1111

Additional details:
- Zeros cannot be represented
- Negative values cannot be represented
- Mantissa is always 1
```

Related PRs:
- [PR-107127](https://github.com/llvm/llvm-project/pull/107127)
[APFloat] Add APFloat support for E8M0 type
- [PR-105573](https://github.com/llvm/llvm-project/pull/105573) [MLIR]
Add f6E3M2FN type - was used as a template for this PR
- [PR-107999](https://github.com/llvm/llvm-project/pull/107999) [MLIR]
Add f6E2M3FN type
- [PR-108877](https://github.com/llvm/llvm-project/pull/108877) [MLIR]
Add f4E2M1FN type
2024-10-04 09:23:12 +02:00
Sergey Kozub
2c58063435
[MLIR] Add f4E2M1FN type (#108877)
This PR adds `f4E2M1FN` type to mlir.

`f4E2M1FN` type is proposed in [OpenCompute MX
Specification](https://www.opencompute.org/documents/ocp-microscaling-formats-mx-v1-0-spec-final-pdf).
It defines a 4-bit floating point number with bit layout S1E2M1. Unlike
IEEE-754 types, there are no infinity or NaN values.

```c
f4E2M1FN
- Exponent bias: 1
- Maximum stored exponent value: 3 (binary 11)
- Maximum unbiased exponent value: 3 - 1 = 2
- Minimum stored exponent value: 1 (binary 01)
- Minimum unbiased exponent value: 1 − 1 = 0
- Has Positive and Negative zero
- Doesn't have infinity
- Doesn't have NaNs

Additional details:
- Zeros (+/-): S.00.0
- Max normal number: S.11.1 = ±2^(2) x (1 + 0.5) = ±6.0
- Min normal number: S.01.0 = ±2^(0) = ±1.0
- Min subnormal number: S.00.1 = ±2^(0) x 0.5 = ±0.5
```

Related PRs:
- [PR-95392](https://github.com/llvm/llvm-project/pull/95392) [APFloat]
Add APFloat support for FP4 data type
- [PR-105573](https://github.com/llvm/llvm-project/pull/105573) [MLIR]
Add f6E3M2FN type - was used as a template for this PR
- [PR-107999](https://github.com/llvm/llvm-project/pull/107999) [MLIR]
Add f6E2M3FN type
2024-09-24 08:22:48 +02:00
Sergey Kozub
73d83f20c9
[MLIR] Add f6E2M3FN type (#107999)
This PR adds `f6E2M3FN` type to mlir.

`f6E2M3FN` type is proposed in [OpenCompute MX
Specification](https://www.opencompute.org/documents/ocp-microscaling-formats-mx-v1-0-spec-final-pdf).
It defines a 6-bit floating point number with bit layout S1E2M3. Unlike
IEEE-754 types, there are no infinity or NaN values.

```c
f6E2M3FN
- Exponent bias: 1
- Maximum stored exponent value: 3 (binary 11)
- Maximum unbiased exponent value: 3 - 1 = 2
- Minimum stored exponent value: 1 (binary 01)
- Minimum unbiased exponent value: 1 − 1 = 0
- Has Positive and Negative zero
- Doesn't have infinity
- Doesn't have NaNs

Additional details:
- Zeros (+/-): S.00.000
- Max normal number: S.11.111 = ±2^(2) x (1 + 0.875) = ±7.5
- Min normal number: S.01.000 = ±2^(0) = ±1.0
- Max subnormal number: S.00.111 = ±2^(0) x 0.875 = ±0.875
- Min subnormal number: S.00.001 = ±2^(0) x 0.125 = ±0.125
```

Related PRs:
- [PR-94735](https://github.com/llvm/llvm-project/pull/94735) [APFloat]
Add APFloat support for FP6 data types
- [PR-105573](https://github.com/llvm/llvm-project/pull/105573) [MLIR]
Add f6E3M2FN type - was used as a template for this PR
2024-09-16 21:09:27 +02:00
Sergey Kozub
918222ba43
[MLIR] Add f6E3M2FN type (#105573)
This PR adds `f6E3M2FN` type to mlir.

`f6E3M2FN` type is proposed in [OpenCompute MX
Specification](https://www.opencompute.org/documents/ocp-microscaling-formats-mx-v1-0-spec-final-pdf).
It defines a 6-bit floating point number with bit layout S1E3M2. Unlike
IEEE-754 types, there are no infinity or NaN values.

```c
f6E3M2FN
- Exponent bias: 3
- Maximum stored exponent value: 7 (binary 111)
- Maximum unbiased exponent value: 7 - 3 = 4
- Minimum stored exponent value: 1 (binary 001)
- Minimum unbiased exponent value: 1 − 3 = −2
- Has Positive and Negative zero
- Doesn't have infinity
- Doesn't have NaNs

Additional details:
- Zeros (+/-): S.000.00
- Max normal number: S.111.11 = ±2^(4) x (1 + 0.75) = ±28
- Min normal number: S.001.00 = ±2^(-2) = ±0.25
- Max subnormal number: S.000.11 = ±2^(-2) x 0.75 = ±0.1875
- Min subnormal number: S.000.01 = ±2^(-2) x 0.25 = ±0.0625
```

Related PRs:
- [PR-94735](https://github.com/llvm/llvm-project/pull/94735) [APFloat]
Add APFloat support for FP6 data types
- [PR-97118](https://github.com/llvm/llvm-project/pull/97118) [MLIR] Add
f8E4M3 type - was used as a template for this PR
2024-09-10 10:41:05 +02:00
Diego Caballero
2ac2e9a5b6
[mlir][LLVM] Improve lowering of llvm.byval function arguments (#100028)
When a function argument is annotated with the `llvm.byval` attribute,
[LLVM expects](https://llvm.org/docs/LangRef.html#parameter-attributes)
the function argument type to be an `llvm.ptr`. For example:

```
func.func (%args0 : llvm.ptr {llvm.byval = !llvm.struct<(i32)>} {
  ...
}
```

Unfortunately, this makes the type conversion context-dependent, which
is something that the type conversion infrastructure (i.e.,
`LLVMTypeConverter` in this particular case) doesn't support. For
example, we may want to convert `MyType` to `llvm.struct<(i32)>` in
general, but to an `llvm.ptr` type only when it's a function argument
passed by value.

To fix this problem, this PR changes the FuncToLLVM conversion logic to
generate an `llvm.ptr` when the function argument has a `llvm.byval`
attribute. An `llvm.load` is inserted into the function to retrieve the
value expected by the argument users.
2024-08-08 19:27:54 -07:00
Andrzej Warzyński
673604a539
[mlir][vector] Update docs for scalable vectors (#101842)
Adds a few notes on scalable vectors in the docs for the Vector dialect.
This is mostly "repeating" things from LLVM's LangRef. 

Additionally:

* Adds a few basic tests with scalable vectors (those should've been
  added long time ago),
* Updates a comment in "TypeConverter.cpp" (the current comment is
out-of-date),
* Includes small formatting edits in Vector.md.

**NOTE** Depends on #101813 - only review the top commit
2024-08-06 11:52:55 +01:00
Alexander Pivovarov
eef1d7e377
[MLIR] Add f8E3M4 IEEE 754 type (#101230)
This PR adds `f8E3M4` type to mlir.

`f8E3M4` type  follows IEEE 754 convention

```c
f8E3M4 (IEEE 754)
- Exponent bias: 3
- Maximum stored exponent value: 6 (binary 110)
- Maximum unbiased exponent value: 6 - 3 = 3
- Minimum stored exponent value: 1 (binary 001)
- Minimum unbiased exponent value: 1 − 3 = −2
- Precision specifies the total number of bits used for the significand (mantissa), 
    including implicit leading integer bit = 4 + 1 = 5
- Follows IEEE 754 conventions for representation of special values
- Has Positive and Negative zero
- Has Positive and Negative infinity
- Has NaNs

Additional details:
- Max exp (unbiased): 3
- Min exp (unbiased): -2
- Infinities (+/-): S.111.0000
- Zeros (+/-): S.000.0000
- NaNs: S.111.{0,1}⁴ except S.111.0000
- Max normal number: S.110.1111 = +/-2^(6-3) x (1 + 15/16) = +/-2^3 x 31 x 2^(-4) = +/-15.5
- Min normal number: S.001.0000 = +/-2^(1-3) x (1 + 0) = +/-2^(-2)
- Max subnormal number: S.000.1111 = +/-2^(-2) x 15/16 = +/-2^(-2) x 15 x 2^(-4) = +/-15 x 2^(-6)
- Min subnormal number: S.000.0001 = +/-2^(-2) x 1/16 =  +/-2^(-2) x 2^(-4) = +/-2^(-6)
```

Related PRs:
- [PR-99698](https://github.com/llvm/llvm-project/pull/99698) [APFloat]
Add support for f8E3M4 IEEE 754 type
- [PR-97118](https://github.com/llvm/llvm-project/pull/97118) [MLIR] Add
f8E4M3 IEEE 754 type
2024-08-02 00:22:11 -07:00
Alexander Pivovarov
019136e30f
[MLIR] Add f8E4M3 IEEE 754 type (#97118)
This PR adds `f8E4M3` type to mlir.

`f8E4M3` type  follows IEEE 754 convention

```c
f8E4M3 (IEEE 754)
- Exponent bias: 7
- Maximum stored exponent value: 14 (binary 1110)
- Maximum unbiased exponent value: 14 - 7 = 7
- Minimum stored exponent value: 1 (binary 0001)
- Minimum unbiased exponent value: 1 − 7 = −6
- Precision specifies the total number of bits used for the significand (mantisa), 
    including implicit leading integer bit = 3 + 1 = 4
- Follows IEEE 754 conventions for representation of special values
- Has Positive and Negative zero
- Has Positive and Negative infinity
- Has NaNs

Additional details:
- Max exp (unbiased): 7
- Min exp (unbiased): -6
- Infinities (+/-): S.1111.000
- Zeros (+/-): S.0000.000
- NaNs: S.1111.{001, 010, 011, 100, 101, 110, 111}
- Max normal number: S.1110.111 = +/-2^(7) x (1 + 0.875) = +/-240
- Min normal number: S.0001.000 = +/-2^(-6)
- Max subnormal number: S.0000.111 = +/-2^(-6) x 0.875 = +/-2^(-9) x 7
- Min subnormal number: S.0000.001 = +/-2^(-6) x 0.125 = +/-2^(-9)
```

Related PRs:
- [PR-97179](https://github.com/llvm/llvm-project/pull/97179) [APFloat]
Add support for f8E4M3 IEEE 754 type
2024-07-22 23:20:28 -07:00
Matthias Springer
acc159aea1
[mlir][Transforms] Dialect conversion: Fix missing source materialization (#97903)
This commit fixes a bug in the dialect conversion. During a 1:N
signature conversion, the dialect conversion did not insert a cast back
to the original block argument type, producing invalid IR.

See `test-block-legalization.mlir`: Without this commit, the operand
type of the op changes because an `unrealized_conversion_cast` is
missing:
```
"test.consumer_of_complex"(%v) : (!llvm.struct<(f64, f64)>) -> ()
```

To implement this fix, it was necessary to change the meaning of
argument materializations. An argument materialization now maps from the
new block argument types to the original block argument type. (It now
behaves almost like a source materialization.) This also addresses a
`FIXME` in the code base:
```
// FIXME: The current argument materialization hook expects the original
// output type, even though it doesn't use that as the actual output type
// of the generated IR. The output type is just used as an indicator of
// the type of materialization to do. This behavior is really awkward in
// that it diverges from the behavior of the other hooks, and can be
// easily misunderstood. We should clean up the argument hooks to better
// represent the desired invariants we actually care about.
```

It is no longer necessary to distinguish between the "output type" and
the "original output type".

Most type converter are already written according to the new API. (Most
implementations use the same conversion functions as for source
materializations.) One exception is the MemRef-to-LLVM type converter,
which materialized an `!llvm.struct` based on the elements of a memref
descriptor. It still does that, but casts the `!llvm.struct` back to the
original memref type. The dialect conversion inserts a target
materialization (to `!llvm.struct`) which cancels out with the other
cast.

This commit also fixes a bug in `computeNecessaryMaterializations`. The
implementation did not account for the possibility that a value was
replaced multiple times. E.g., replace `a` by `b`, then `b` by `c`.

This commit also adds a transform dialect op to populate SCF-to-CF
patterns. This transform op was needed to write a test case. The bug
described here appears only during a complex interplay of 1:N signature
conversions and op replacements. (I was not able to trigger it with ops
and patterns from the `test` dialect without duplicating the `scf.if`
pattern.)

Note for LLVM integration: Make sure that all
`addArgument/Source/TargetMaterialization` functions produce an SSA of
the specified type.

Depends on #98743.
2024-07-15 17:04:56 +02:00
Matthias Springer
9e8ccf6b64
[mlir][Conversion] FuncToLLVM: Simplify bare-pointer handling (#96393)
Before this commit, there used to be a workaround in the
`func.func`/`gpu.func` op lowering when the bare-pointer calling
convention is enabled. This workaround "patched up" the argument
materializations for memref arguments. This can be done directly in the
argument materialization functions (as the TODOs in the code base
indicate).

This commit effectively reverts back to the old implementation
(a664c14001fa2359604527084c91d0864aa131a4) and adds additional checks to
make sure that bare pointers are used only for function entry block
arguments.
2024-06-24 08:38:26 +02:00
Ramkumar Ramachandra
e843f029b4
mlir: fix incorrect usages of divideCeilSigned (#95680)
Follow up on #95087 to fix incorrect usage instances of
divideCeilSigned.
2024-06-17 11:43:57 +01:00
Ramkumar Ramachandra
0fb216fb2f
mlir/MathExtras: consolidate with llvm/MathExtras (#95087)
This patch is part of a project to move the Presburger library into
LLVM.
2024-06-11 23:00:02 +01:00
Jeff Niu
e553ac4d81
[mlir][llvm] Port overflowFlags to a native operation property (RELAND) (#89410)
This PR changes the LLVM dialect's IntegerOverflowFlags to be stored on
operations as native properties.

Reland to fix flang
2024-04-19 09:23:00 -07:00
Valentin Clement (バレンタイン クレメン)
13beabe5e9
Revert "[mlir][llvm] Port overflowFlags to a native operation property" (#89344)
Reverts llvm/llvm-project#89312 as it breaks all flang buildbots
2024-04-18 22:15:42 -07:00
Jeff Niu
0c41eea474
[mlir][llvm] Port overflowFlags to a native operation property (#89312)
This PR changes the LLVM dialect's IntegerOverflowFlags to be stored on
operations as native properties.
2024-04-18 15:35:39 -07:00
Oleksandr "Alex" Zinenko
43bc81d748
[mlir] fix LLVM type converter for structs (#73231)
Existing implementation of the LLVM type converter for LLVM structs
containing incompatible types was attempting to change identifiers of
the struct in case of name clash post-conversion (all identified structs
have different names post-conversion since one cannot change the body of
the struct once initialized). Beyond a trivial error of not updating the
counter in renaming, this approach was broken for recursive structs that
can't be made aware of the renaming and would use the pre-existing
struct with clashing name instead.

For example, given

`!llvm.struct<"_Converted.foo", (struct<"_Converted.foo">, f32)>`

the following type

`!llvm.struct<"foo", (struct<"foo", index>)>`

would incorrectly convert to

```
!llvm.struct<"_Converted_1.foo",
             (struct<"_Converted.foo",
	             (struct<"_Converted.foo">, f32)>)>
```

Remove this incorrect renaming and simply refuse to convert types if it
would lead to identifier clashes for structs with different bodies.
Document the expectation that such generated names are reserved and must
not be present in the input IR of the converter. If we ever actually
need to use handle such cases, this can be achieved by temporarily
renaming structs with reserved identifiers to an unreserved name and
back in a pre/post-processing pass that does _not_ use the type
conversion infra.
2023-11-23 22:21:39 +01:00
Christian Ulmann
4983432f17
[MLIR][LLVM] Remove typed pointers from the LLVM dialect (#71285)
This commit removes the support for typed pointers from the LLVM
dialect. Typed pointers have been deprecated for a while and thus this
removal was announced in a PSA:

https://discourse.llvm.org/t/psa-removal-of-typed-pointers-from-the-llvm-dialect/74502

This change includes:
- Changing the ` LLVMPointerType`
- Removing remaining usages of the builders and the now removed element
type
- Fixing assembly formats that require fully qualified pointer types
- Updating ODS pointer constraints
2023-11-06 15:48:03 +01:00
Christian Ulmann
97a238e863
[MLIR][LLVM] Remove typed pointer conversion utils (#71169)
This commit removes the no longer required type pointer helpers from the
LLVM dialect conversion utils. Typed pointers have been deprecated for a
while now and it's planned to soon remove them from the LLVM dialect.

Related PSA:
https://discourse.llvm.org/t/psa-removal-of-typed-pointers-from-the-llvm-dialect/74502
2023-11-03 13:02:35 +01:00
Christian Ulmann
b28a296cdf
[MLIR][MemRefToLLVM] Remove typed pointer support (#70909)
This commit removes the support for lowering MemRefToLLVM to LLVM
dialect with typed pointers. Typed pointers have been deprecated for a
while now and it's planned to soon remove them from the LLVM dialect.

Related PSA:
https://discourse.llvm.org/t/psa-removal-of-typed-pointers-from-the-llvm-dialect/74502
2023-11-02 07:35:58 +01:00
Benjamin Maxwell
3be3883e6d
[mlir][VectorOps] Support string literals in vector.print (#68695)
Printing strings within integration tests is currently quite annoyingly
verbose, and can't be tucked into shared helpers as the types depend on
the length of the string:

```
llvm.mlir.global internal constant @hello_world("Hello, World!\0")

func.func @entry() {
  %0 = llvm.mlir.addressof @hello_world : !llvm.ptr<array<14 x i8>>
  %1 = llvm.mlir.constant(0 : index) : i64
  %2 = llvm.getelementptr %0[%1, %1]
    : (!llvm.ptr<array<14 x i8>>, i64, i64) -> !llvm.ptr<i8>
  llvm.call @printCString(%2) : (!llvm.ptr<i8>) -> ()
  return
}
```

So this patch adds a simple extension to `vector.print` to simplify
this:
```
func.func @entry() {
   // Print a vector of characters ;)
   vector.print str "Hello, World!"
   return
}
```

Most of the logic for this is now shared with `cf.assert` which already
does something similar.

Depends on #68694
2023-10-24 09:34:14 +01:00
Tobias Gysi
85175edd4e
[mlir][llvm] Replace NullOp by ZeroOp (#67183)
This revision replaces the LLVM dialect NullOp by the recently
introduced ZeroOp. The ZeroOp is more generic in the sense that it
represents zero values of any LLVM type rather than null pointers only.

This is a follow to https://github.com/llvm/llvm-project/pull/65508
2023-09-25 11:11:52 +02:00
Benjamin Maxwell
665995b918 [mlir][Conversion] Allow lowering to fixed arrays of scalable vectors
This allows lowering vector types like: vector<3x[4]> or vector<3x2x[4]>
to LLVM IR, i.e. vectors where the trailing dim is scalable.

This is contingent on:
https://discourse.llvm.org/t/rfc-enable-arrays-of-scalable-vector-types/72935

More tests will be added in later patches, however, some MLIR fixes are
needed first.

Depends on: D158517

Reviewed By: awarzynski

Differential Revision: https://reviews.llvm.org/D158752
2023-09-15 09:33:18 +00:00
Cullen Rhodes
38eb55a130
[mlir][llvm] Return failure from type converter for n-D scalable vectors (#65450)
This patch changes vector type conversion to return failure on n-D
scalable vector types instead of asserting.

This is an alternative approach to #65261 that aims to enable lowering
of Vector ops directly to ArmSME intrinsics where possible, and seems
more consistent with other type conversions. It's trivial to hit the
assert at the moment and it could be interpreted as n-D scalable vector
types being a bug, when they're valid types in the Vector dialect.

By returning failure it will generally fail more gracefully,
particularly for release builds or other builds where assertions are
disabled.
2023-09-11 09:31:48 +01:00
Adrian Kuegel
fb03cd5af1 [mlir] Apply ClangTidy finding (NFC)
Remove redundant .get() on a smart pointer.
2023-09-04 08:44:49 +02:00
Mikhail Goncharov
0a0aff2d24 fix unused variable warnings in conditionals
warning was updated in 92023b15099012a657da07ebf49dd7d94a260f84
2023-08-30 19:09:27 +02:00
Mehdi Amini
dc3dc97410 Remove the conversionCallStack from the MLIR TypeConverter
This vector keeps tracks of recursive types through the recursive invocations
of `convertType()`. However this is something only useful for some specific
cases, in which the dedicated conversion callbacks can handle this stack
privately.

This allows removing a mutable member of the type converter.

Reviewed By: springerm

Differential Revision: https://reviews.llvm.org/D158351
2023-08-27 16:14:31 -07:00
Matthias Springer
ce254598b7 [mlir][Conversion] Store const type converter in ConversionPattern
ConversionPatterns do not (and should not) modify the type converter that they are using.

* Make `ConversionPattern::typeConverter` const.
* Make member functions of the `LLVMTypeConverter` const.
* Conversion patterns take a const type converter.
* Various helper functions (that are called from patterns) now also take a const type converter.

Differential Revision: https://reviews.llvm.org/D157601
2023-08-14 09:03:11 +02:00
Alex Zinenko
e98e59955e Revert "Foo"
This reverts commit 3c9aa10c57cf0833ff108ecf9ffbb512bd96cc89.

No proper description of the commit.
2023-08-04 13:30:12 +00:00
Nicolas Vasilache
3c9aa10c57 Foo 2023-08-04 11:06:17 +00:00
Nicolas Vasilache
620e2bb20c [mlir][LLVM] NFC - Remove createIndexConstant method
This revision removes the createIndexConstant method, which implicitly creates constants of the
getIndexType type and updates all uses to the more explicit createIndexAttrConstant which requires
an explicit Type parameter.

This is an NFC step towards entangling index type conversion in LLVM lowering.

The selection of which index type to use requires finer granularity than the existing
implementations which all rely on pass level flags and end up in mismatches, especially on GPUs
with multiple address spaces of different capacities.

This revision also includes an NFC fix to MemRefToLLVM.cpp that prevents a crash in cases where
an integer memory space cannot be derived for a MemRef.

Differential Revision: https://reviews.llvm.org/D156854
2023-08-02 07:24:29 +00:00
Andrzej Warzynski
faf77f8dec [mlir][nfc] Clarify the limitation on scalable vectors
When converting/lowering to LLVM, MLIR does not support n-D scalable
vectors at the moment. This patch simply clarifies an assert that's
meant to catch such unsupported cases.

Note that we may want to relax this condition in the future.

Differential Revision: https://reviews.llvm.org/D154302
2023-07-19 07:00:35 +00:00
Andrzej Warzynski
f22af204ed [mlir][VectorType] Remove numScalableDims from the vector type
This is a follow-up of https://reviews.llvm.org/D153372 in which
`numScalableDims` (single integer) was effectively replaced with
`isScalableDim` bitmask.

This change is a part of a larger effort to enable scalable
vectorisation in Linalg. See this RFC for more context:
  * https://discourse.llvm.org/t/rfc-scalable-vectorisation-in-linalg/

Differential Revision: https://reviews.llvm.org/D153412
2023-06-28 13:53:45 +01:00
Andrzej Warzynski
79c83e12c8 [mlir][VectorType] Allow arbitrary dimensions to be scalable
At the moment, only the trailing dimensions in the vector type can be
scalable, i.e. this is supported:

    vector<2x[4]xf32>

and this is not allowed:

    vector<[2]x4xf32>

This patch extends the vector type so that arbitrary dimensions can be
scalable. To this end, an array of bool values is added to every vector
type to denote whether the corresponding dimensions are scalable or not.
For example, for this vector:

  vector<[2]x[3]x4xf32>

the following array would be created:

  {true, true, false}.

Additionally, the current syntax:

  vector<[2x3]x4xf32>

is replaced with:

  vector<[2]x[3]x4xf32>

This is primarily to simplify parsing (this way, the parser can easily
process one dimension at a time rather than e.g. tracking whether
"scalable block" has been entered/left).

NOTE: The `isScalableDim` parameter of `VectorType` (introduced in this
patch) makes `numScalableDims` redundant. For the time being,
`numScalableDims` is preserved to facilitate the transition between the
two parameters. `numScalableDims` will be removed in one of the
subsequent patches.

This change is a part of a larger effort to enable scalable
vectorisation in Linalg. See this RFC for more context:
  * https://discourse.llvm.org/t/rfc-scalable-vectorisation-in-linalg/

Differential Revision: https://reviews.llvm.org/D153372
2023-06-27 19:21:59 +01:00
Krzysztof Drewniak
73eecc9ca4 [mlir] Convert 8-bit float types to i8
Whereas LLVM currently doesn't have any types for 8-bit floats, and
whereas existing 8-bit float APIs (for instance, the AMDGCN
intrinsics) take such floats as (packed) bytes, translate the MLIR
8-bit float types to i8 during LLVM lowering.

In order to not special-case arith.constant for bitcasting constants
to their integer form, amend the MLIR to LLVM translator to turn 8-bit
float constants into i8 constants with the same value (by use of
APFloat's bitcast method).

This change can be reverted once LLVM has 8-bit float types.

Reviewed By: gysit

Differential Revision: https://reviews.llvm.org/D153160
2023-06-26 17:42:00 +00:00
Christian Ulmann
48b126e30b [mlir][llvm] Ensure immediate usage in intrinsics
This commit changes intrinsics that have immarg parameter attributes to
model these parameters as attributes, instead of operands. Using
operands only works if the operation is an `llvm.mlir.constant`,
otherwise the exported LLVMIR is invalid.

Reviewed By: gysit

Differential Revision: https://reviews.llvm.org/D151692
2023-06-12 06:57:42 +00:00
Tres Popp
68f58812e3 [mlir] Move casting calls from methods to function calls
The MLIR classes Type/Attribute/Operation/Op/Value support
cast/dyn_cast/isa/dyn_cast_or_null functionality through llvm's doCast
functionality in addition to defining methods with the same name.
This change begins the migration of uses of the method to the
corresponding function call as has been decided as more consistent.

Note that there still exist classes that only define methods directly,
such as AffineExpr, and this does not include work currently to support
a functional cast/isa call.

Context:
- https://mlir.llvm.org/deprecation/ at "Use the free function variants
  for dyn_cast/cast/isa/…"
- Original discussion at https://discourse.llvm.org/t/preferred-casting-style-going-forward/68443

Implementation:
This patch updates all remaining uses of the deprecated functionality in
mlir/. This was done with clang-tidy as described below and further
modifications to GPUBase.td and OpenMPOpsInterfaces.td.

Steps are described per line, as comments are removed by git:
0. Retrieve the change from the following to build clang-tidy with an
   additional check:
   main...tpopp:llvm-project:tidy-cast-check
1. Build clang-tidy
2. Run clang-tidy over your entire codebase while disabling all checks
   and enabling the one relevant one. Run on all header files also.
3. Delete .inc files that were also modified, so the next build rebuilds
   them to a pure state.

```
ninja -C $BUILD_DIR clang-tidy

run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
               -header-filter=mlir/ mlir/* -fix

rm -rf $BUILD_DIR/tools/mlir/**/*.inc
```

Differential Revision: https://reviews.llvm.org/D151542
2023-05-26 10:29:55 +02:00
Fabian Mora
041f1abee1 [mlir][memref] Fix num elements in lowering of memref.alloca op to LLVM
Fixes a mistake in the lowering of memref.alloca to llvm.alloca, as llvm.alloca uses the number of elements to allocate in the stack and not the size in bytes.

Reference:
LLVM IR: https://llvm.org/docs/LangRef.html#alloca-instruction
LLVM MLIR: https://mlir.llvm.org/docs/Dialects/LLVM/#llvmalloca-mlirllvmallocaop

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D150705
2023-05-22 16:23:00 +00:00
Quentin Colombet
bba9209f1d [MemRefToLLVM][NFC] Use early exit for the getter of the buffer ptr
Address review comment from https://reviews.llvm.org/D148947
2023-05-16 10:54:25 +02:00
Tres Popp
5550c82189 [mlir] Move casting calls from methods to function calls
The MLIR classes Type/Attribute/Operation/Op/Value support
cast/dyn_cast/isa/dyn_cast_or_null functionality through llvm's doCast
functionality in addition to defining methods with the same name.
This change begins the migration of uses of the method to the
corresponding function call as has been decided as more consistent.

Note that there still exist classes that only define methods directly,
such as AffineExpr, and this does not include work currently to support
a functional cast/isa call.

Caveats include:
- This clang-tidy script probably has more problems.
- This only touches C++ code, so nothing that is being generated.

Context:
- https://mlir.llvm.org/deprecation/ at "Use the free function variants
  for dyn_cast/cast/isa/…"
- Original discussion at https://discourse.llvm.org/t/preferred-casting-style-going-forward/68443

Implementation:
This first patch was created with the following steps. The intention is
to only do automated changes at first, so I waste less time if it's
reverted, and so the first mass change is more clear as an example to
other teams that will need to follow similar steps.

Steps are described per line, as comments are removed by git:
0. Retrieve the change from the following to build clang-tidy with an
   additional check:
   https://github.com/llvm/llvm-project/compare/main...tpopp:llvm-project:tidy-cast-check
1. Build clang-tidy
2. Run clang-tidy over your entire codebase while disabling all checks
   and enabling the one relevant one. Run on all header files also.
3. Delete .inc files that were also modified, so the next build rebuilds
   them to a pure state.
4. Some changes have been deleted for the following reasons:
   - Some files had a variable also named cast
   - Some files had not included a header file that defines the cast
     functions
   - Some files are definitions of the classes that have the casting
     methods, so the code still refers to the method instead of the
     function without adding a prefix or removing the method declaration
     at the same time.

```
ninja -C $BUILD_DIR clang-tidy

run-clang-tidy -clang-tidy-binary=$BUILD_DIR/bin/clang-tidy -checks='-*,misc-cast-functions'\
               -header-filter=mlir/ mlir/* -fix

rm -rf $BUILD_DIR/tools/mlir/**/*.inc

git restore mlir/lib/IR mlir/lib/Dialect/DLTI/DLTI.cpp\
            mlir/lib/Dialect/Complex/IR/ComplexDialect.cpp\
            mlir/lib/**/IR/\
            mlir/lib/Dialect/SparseTensor/Transforms/SparseVectorization.cpp\
            mlir/lib/Dialect/Vector/Transforms/LowerVectorMultiReduction.cpp\
            mlir/test/lib/Dialect/Test/TestTypes.cpp\
            mlir/test/lib/Dialect/Transform/TestTransformDialectExtension.cpp\
            mlir/test/lib/Dialect/Test/TestAttributes.cpp\
            mlir/unittests/TableGen/EnumsGenTest.cpp\
            mlir/test/python/lib/PythonTestCAPI.cpp\
            mlir/include/mlir/IR/
```

Differential Revision: https://reviews.llvm.org/D150123
2023-05-12 11:21:25 +02:00
Quentin Colombet
e02d4142dc [MemRefToLLVM] Add a method in MemRefDescriptor to get the buffer addr
This patch pushes the computation of the start address of a memref in one
place (a method in MemRefDescriptor.)

This allows all the (indirect) users of this method to produce the start
address in the same way.

Thanks to this change, we expose more CSEs opportunities and thanks to
that, the backend is able to properly find the `llvm.assume` expression
related to the base address as demonstrated in the added test.

Differential Revision: https://reviews.llvm.org/D148947
2023-04-26 06:12:18 +02:00
Stephan Herhut
6a10381b6f [mlir][llvm] Fix for MemRefBuilder when using opaque pointers.
Loading the offset of an unranked memref descriptor is creating an invalid load.

Differential Revision: https://reviews.llvm.org/D148540
2023-04-18 10:02:23 +02:00
Adrian Kuegel
418c8cbcdd [mlir] Apply ClangTidy fix.
The argument name 'useBarePtrCallConv' does not match the actual
parameter name 'useBarePointerCallConv'.
2023-04-17 13:50:29 +02:00
Alex Zinenko
76ba5ed053 [mlir] LLVM lowering: don't use calling convention in op returns
Conversions to the LLVM dialect have an option to use the "bare pointer"
calling convention that converts memref types differently than the
default convention. It has crept into the conversion of operations that
are not related to calls but do require multiresult-to-struct packing.
Use a similar mechanism for the latter without using the calling
convention.

Reviewed By: gysit

Differential Revision: https://reviews.llvm.org/D148086
2023-04-13 10:56:56 +00:00
Mahesh Ravishankar
162f757206 [mlir][LLVM] Add an attribute to control use of bare-pointer calling convention.
Currently the use of bare pointer calling convention is controlled
globally through use of an option in the `LLVMTypeConverter`. To allow
more fine-grained control use an attribute on a function to drive the
calling convention to use.

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D147494
2023-04-06 16:19:56 +00:00
Jakub Kuderski
8c258fda1f [ADT][mlir][NFCI] Do not use non-const lvalue-refs with enumerate
Replace references to enumerate results with either result_pairs
(reference wrapper type) or structured bindings. I did not use
structured bindings everywhere as it wasn't clear to me it would
improve readability.

This is in preparation to the switch to zip semantics which won't
support non-const lvalue reference to elements:
https://reviews.llvm.org/D144503.

I chose to use values instead of const lvalue-refs because MLIR is
biased towards avoiding `const` local variables. This won't degrade
performance because currently `result_pair` is cheap to copy (size_t
+ iterator), and in the future, the enumerator iterator dereference
will return temporaries anyway.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D146006
2023-03-15 10:43:56 -04:00
Kazu Hirata
05423905d0 [mlir] Use std::optional instead of llvm::Optional (NFC)
This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2023-02-14 20:33:36 -08:00
Krzysztof Drewniak
7fb9bbe5f0 [mlir][Memref] Add memref.memory_space_cast and its lowerings
Address space casts are present in common MLIR targets (LLVM, SPIRV).
Some planned rewrites (such as one of the potential fixes to the fact
that the AMDGPU backend requires alloca() to live in address space 5 /
the GPU private memory space) may require such casts to be inserted
into MLIR code, where those address spaces could be represented by
arbitrary memory space attributes.

Therefore, we define memref.memory_space_cast and its lowerings.

Depends on D141293

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D141148
2023-02-09 21:44:57 +00:00
Krzysztof Drewniak
d0f19ce774 [mlir] Handle different pointer sizes in unranked memref descriptors
The code for unranked memref descriptors assumed that
sizeof(!llvm.ptr) == lizeof(!llvm.ptr<N>) for all address spaces N.
This is not always true (ex. the AMDGPU compiler backend has
sizeof(!llvm.ptr) = 64 bits but sizeof(!llvm.ptr<5>) = 32 bits, where
address space 5 is used for stack allocations). While this is merely
an overallocation in the case where a non-0 address space has pointers
smaller than the default, the existing code could cause OOB memory
accesses when sizeof(!llvm.ptr<N>) > sizeof(!llvm.ptr).

So, add an address spaces parameter to computeSizes in order to
partially resolve this class of bugs. Note that the LLVM data layout
in the conversion passes is currently set to "" and not constructed
from the MLIR data layout or some other source, but this could change
in the future.

Depends on D142159

Reviewed By: ftynse

Differential Revision: https://reviews.llvm.org/D141293
2023-02-09 19:14:58 +00:00