1. Clamps OOB start index to 0 in slice folder
2. Adds a more descriptive `emitError` in slice folder if the creation
of the `DenseElementsAttr` would fail due to a bad result shape.
3. Fixes the `onnx.Shape` lowering to default to `inputRank` for `end`
instead of `-1`. When `end==-1` the last element was missing when
slicing.
Removes a boolean variable that is used only for an assertion, and
inlines the condition into the assertion.
Signed-off-by: Max Dawkins <max.dawkins@gmail.com>
### new patterns:
1. Propagates `aten.broadcast_to` ops of a single value to an
`aten.full` op
2. Propagates arithmetic operations through a templated class which
associates some tensor arithmetic ops to their integer-scalar
counterparts. These are a major blocker right now, since some models
have a bunch of rank 0 arithmetic being done with tensor ops. See the
lit test for an interesting example that pads an input to the smallest
shape which will become divisible by twelve in `dim0`. If you think this
is convoluted, you haven't been staring at ONNX generated IR long
enough.
3. Adds a stronger folder for `aten.eq.int` to fold `size.int == 0` to
`false`. See the comment in that conversion pattern for more
justification as to why it is acceptable to make this assumption here.
This is another major blocker for models, since this lack of folding
propagates to lack of folding for subsequent `where.self` operations.
4. Add `AtenSqueezeDim` to the existing `FoldAtenSqueezeOpPattern`
### other changes:
1. Add two new anchor ops: `AtenArangeStartStepOp` and
`Torch::RuntimeAssertOp`. I've checked all possible sources of the
runtime assert ops and it is always shape related. The Arange op only
takes int inputs, and these are all shape related. Adds a size check to
getting a list from literal ops.
2. Improved folders for int arithmetic ops to fold some common patterns.
3. adds the ability to get some values from scalar-tensor ops to
getListFromTensor.
4. further cleans up getListFromTensor for readability.
### points to scrutinize:
1. I made the choice to scalarize `div.Tensor` (int dtype result) to
`floordiv.int`. This is because our shape computations involving this
kind of arithmetic are never negative in practice, and we don't have a
"round towards zero" scalar int divide counterpart.
2. Anchoring on `RuntimeAssertOp` sounds really suspicious, and if
someone happens to add a runtime assert in the future that doesn't boil
down to shapes, then it would add to the worklist considerably. We might
be able to get around this by adding "NoMemoryEffect" to ops which are
"ReadOnly" so that the inputs for the runtime asserts get cse'd with
existing elements of the worklist before we even get to this pass.
This is a first step towards reworking the scalarize-shapes pass which
has been integral to our ONNX frontend path detangling shape
computations.
## Purpose:
1. Restrict the scope of the pass to only apply to op sequences which
are used to compute shapes.
2. Make the pass more efficient by applying patterns in an appropriate
order for scalarization propagation.
3. Report failed scalarization patterns for easier debugging (Not yet
implemented). I can't seem to find a good path for this right now to
capture the right diagnostics. I'd like to defer this addition to a
later patch so we can add some high-value patterns to this pass in the
meantime.
With these changes, some reworking of the conversions themselves will be
necessary.
1. The removal of the SqueezeDim fold pattern was an appropriate fix to
avoid folding a pattern that may be needed to propagate further. The
reversal of pattern application order uncovered this bug. The addition
of rank 0 item logic was added to replace the functionality needed from
the squeeze dim pattern.
2. Rework getListFromTensor to modify a `SmallVector<OpFoldResult>` to
allow processing value tensor literals without immediately materializing
the ints. This should factor out a significant portion of code that was
used in specific cases to handle constants.
## RFC 1:
Currently, we are going to add all prim list of int ops to the worklist.
Can anyone identify problems with uniformly anchoring on prim lists of
ints? E.g. Does there exist a Torch Op satisfying all of the following
conditions:
1. Accepts a list of constant ints, LIST, as an input
2. The role of LIST is **not** shape related. All the examples I can
think of are indeed shape related: padding ints passed to a pad op,
kernel size ints passed to a conv op, size ints passed to a view op,
etc.
4. The LIST is not gotten entirely from scalars already.
If there does not exist a torch op satisfying all three of those
conditions, I think it will be safe to "anchor" on prim lists of ints.
### Conclusion for RFC 1:
I just scanned through the `GeneratedTorchOps.td` and `TorchOps.td` for
all references of `AnyTorchListOfTorchIntType` and verified this will
not be problematic to apply in any of those cases.
## RFC 2:
What should I use to report failed scalarization?
Like my dumb idea was just to walk back through the func op after
applying the passes and check if anything in the worklist is still a
tensor. If so, emit/log a warning. It certainly works, since you can
just look at the warnings and start debugging from the last printed
warning upwards, but there has to be a better way to handle this without
walking back through the func.func op.
### Conclusion for RFC 2:
I tried a few things without much success. The fundamental problem is
that identifying the cause of a failed scalarization could be myriad:
1. We could be missing a pattern for an op entirely: E.g., a pattern we
need is scalarizing rank0 arithmetic ops (e.g. AtenMulTensorOp ->
AtenMulIntOp).
2. We could fail a scalarization pattern because it should fold instead.
This is specifically the case for rank0 where.self ops. These ops MUST
fold, or we need to have custom lowering logic for the rank 0 case.
3. Walking through the func op a second time and emiting a warning for
ops that have tensor result types seems to give locations that are
inconsistent or hard to track in the converted IR. Doing this on IR that
doesn't apply any patterns seems to give decent information, but it's
still dramatically insufficient considering how complex these patterns
can get, and still takes manually reading IR to try and figure out what
is really blocking the simplification.
I'd like to skip out on fleshing out the error reporting for now and
come back to it after iterating a few time on the patterns.
This was preventing dynamic dims in an ONNX model from being reified (causing the generation of `tensor.cast`s and preventing fusion in iree):
```mlir
%2 = torch.vtensor.literal(dense<[4, 256]> : tensor<2xsi64>) : !torch.vtensor<[2],si64>]
%7 = torch.prim.ListConstruct %int2 : (!torch.int) -> !torch.list<int>
%8 = torch.aten.reshape %2, %7 : !torch.vtensor<[2],si64>, !torch.list<int> -> !torch.vtensor<[2],si64>
//... chain of foldable ops linking %2 to the `shape` operand of a `torch.aten.broadcast_to ... -> !torch.vtensor<[?,?],si64>`
```
The op can be valid with no attached shape symbols if they are not
required by the corresponding affine map. Fix the verifier to consider
number of arguments for both.
Fixes https://github.com/iree-org/iree/issues/18562.
During canonicalization pass on `AtenUnflattenIntOp`, if the second dim
was statically equal to one, we would create an `AtenAddIntOp` to add
one to the dimension obtained from `op.getDim()`. This, when passed into
`Torch::unsqueezeTensor()`, would make it get interpreted as
non-constant, which would lead to MLIR failing an assertion when
`UnsqueezeOp` would later get lowered into `ExpandShapeOp`, as the
output of the `UnsqueezeOp` would consist of only dynamic dims.
This patch fixes this behavior, by extracting the integer value from the
dim if it was constant, and then emitting a `ConstantIntOp` from
(dim+1). This creates an output with static shape.
Addresses an issue in <https://github.com/llvm/torch-mlir/issues/3651>
where some unflatten ops generated from onnx models weren't propagating
static shape information. It may be necessary to add further
optimizations for the more general case when some static information is
present in the unflatten (or possibly reshape/view) op's `sizes` list,
but not reflected in the output shape. These ops will only successfully
infer shapes if the `sizes` list is gotten from a list of constant ints
(with possibly one -1). A common example where this fails is when some
of the `sizes` are determined from `aten.size.int` ops on dynamic
tensors, and other `sizes` are known statically.
This PR includes:
- a canonicalizer for `aten.unflatten.int` which converts to
`aten.unsqueeze` when it is expanding one dim to two, and one of the new
dims is statically 1.
- an improvement to the folder for `aten.__or__.bool` which does not
rely on *both* operands being static.
This PR add `floordiv` to the `PY_BUILTIN_TO_TORCH_OP`. For
`aten.mul.int` and `aten.floordiv.int` ops, we add new Canonicalization
Patterns as follow:
```
%1 = torch.aten.mul.int %input, %const-5
%2 = torch.aten.mul.int %1, %const-6
```
Will be replaced by
`torch.aten.mul.int %input, %const-30`
And
```
%1 = torch.aten.mul.int %input, %const-5
%2 = torch.aten.floordiv.int %1, %const-5
```
Will directly return `%input`
This PR also relaxes the `float` type constraint in TorchToTosa for the
`AtenRsubScalarOp` conversion.
To test:
`cmake --build build --target check-torch-mlir-all`
The static uneven divisible AdaptiveAvgPool2d means that although the
input size is not an integer multiple of ouput size, but the kernel and
stride size can also be fixed (not dynamic). The derivation logic of
kernel and stride size is consistent with
torch/_decomp/decomposations.py:adaptive_avg_pool2d as described in the
following:
1. Stride Size
Firstly , derive the start index in each reduce operation according to
the output size (`n`), `start_index = ([0, 1, ..., n - 1] * input_size)
// output_size`. For each index `k`, if `k * (input_size % output_size)
< output_size`, then the current and previous stride keeps the same as
`input_size // output_size`. So suppose `(n-1) * (input_size %
output_size) < output_size`, the stride in the whole AdaptiveAvgPool2d
process keeps static, as `input_size // output_size`.
2. Kernel Size
torch/_decomp/decomposations.py:adaptive_avg_pool2d calculates a static
kernel size when the input/output sizes satisfy either of the two
conditions, `input_size % output_size == 0` or `output_size %
(input_size % output_size) == 0`. Here if `input_size % output_size ==
0`, then the kernel size equals `input_size // output_size`, otherwise
`input_size // output_size + 1.`
Fix the pad tensor rearrangement such that we change the representation
from [x1_begin, x2_begin, ..., x1_end, x2_end,...] to [xn_begin, xn_end,
...., x2_begin, x2_end, x1_begin, x1_end] where x1, x2 .. xn are the
dimensions of the pads tensor argument.
---------
Co-authored-by: zjgarvey <zjgarvey@gmail.com>
Co-authored-by: zjgarvey <47986913+zjgarvey@users.noreply.github.com>
Due to the custom operation parser, the print and parser were expecting
two different forms.
One having the dictionary before the value and the other after.
Following the format of the other constants ops, the constant.int will
follow the `value attr-dict` format. Updated the parser accordingly.
This bump triggered an upstream assert. Includes a WAR for #3506.
Also includes several things I needed to do to repro:
* When TORCH_MLIR_TEST_CONCURRENCY=1, test runs will be printed.
* Added TORCH_MLIR_TEST_VERBOSE=1 handling to enable verbose mode
(useful on CI).
---------
Co-authored-by: Stella Laurenzo <stellaraccident@gmail.com>
There is currently no int16 quantization support in torch. This patch
adds a new mlir type to correspond to the missing "torch.qint16" type,
and enables lowering of quantization-related onnx ops using int16 types.
In follow-up patches, custom quantization logic for ops like
aten.matmul/aten.mm/aten.convolution may need to be revisited to allow
support for qint16. The passes in FuseQuantizedOps.cpp may also need
slight modifications.
Updates:
- some unsupported modes are now going to report a match failure for
unsupported coordinate transformation modes.
- fixes a bug that was introduced in the last patch for resize (my
bad...)
- uses actual x and y coordinates for computing weights in bilinear
interpolation (rather than eps modified values)
- slightly simplifies the bilinear interpolation payload for readability
and performance
- passes coordinate transformation mode information from an onnx.Resize
op to the mode string for the aten._interpolate op. This allows us to
perform custom logic in the torch->linalg lowering to support
onnx.Resize options without losing the default behaviors of the
interpolate op.
In constant folding progress, a new constant op will be created
according to the origin op's result type.
See the code in TorchDialect.cpp.
```cpp
Operation *TorchDialect::materializeConstant(OpBuilder &builder,
Attribute value, Type type,
Location loc) {
if (auto integerType = dyn_cast<Torch::IntType>(type))
return builder.create<Torch::ConstantIntOp>(loc, cast<IntegerAttr>(value));
if (auto floatType = dyn_cast<Torch::FloatType>(type))
return builder.create<Torch::ConstantFloatOp>(loc, cast<FloatAttr>(value));
if (auto numberType = dyn_cast<Torch::NumberType>(type)) {
if (auto floatValue = dyn_cast<mlir::FloatAttr>(value)) {
return builder.create<Torch::ConstantNumberOp>(loc, floatValue);
} else if (auto intValue = dyn_cast<mlir::IntegerAttr>(value)) {
return builder.create<Torch::ConstantNumberOp>(loc, intValue);
}
}
if (isa<Torch::BoolType>(type)) {
return builder.create<Torch::ConstantBoolOp>(loc, cast<IntegerAttr>(value));
}
if (isa<Torch::NoneType>(type))
return builder.create<ConstantNoneOp>(loc);
if (auto stringAttr = dyn_cast<StringAttr>(value))
return builder.create<ConstantStrOp>(loc, stringAttr);
if (auto elementsAttr = dyn_cast<ElementsAttr>(value)) {
// Only !torch.vtensor can be constant folded. !torch.tensor has
// non-trivial aliasing semantics which prevent deduplicating it.
assert(isa<ValueTensorType>(type) && "should be a vtensor type!");
return builder.create<ValueTensorLiteralOp>(loc, elementsAttr);
}
return nullptr;
}
```
So when the op has a tensor result type, it must be "ValueTensorType"
due to the **assert** statement. However, many fold methods in
TorchOps.cpp only have a judgment of "BaseTensorType".
While playing with TorchDynamo on ResNet18. I notice following issues:
- `prims.convert_element_type` can’t be canonicalized even if the input
and the output share the same type
- `aten.max_pool2d_with_indices` is always used instead of
`aten.max_pool2d`, even if the second returned output (indices) has no
user
This PR fixes above issues by adding a folder to the
PrimsConvertElementTypeOp and a canonicalizer to the
AtenMaxPool2dWithIndicesOp
Lit test:
`cmake --build build --target check-torch-mlir-all`
---------
Co-authored-by: Ze Zhang <ze.zhang@getcruise.com>