IVGCVSW-7455 Workaround to allow CLBatchMatMul to parse some 4D models

 * Added ability to reduce dimension sizes when calling BuildArmComputeTensorInfo or
   BuildArmComputeTensorShapes, this will attempt to remove leading 1s in order to
   squeeze the number of dimensions but retain the size.
 * Changed ClBatchMatMulWorkload to attempt to squeeze the number of dimensions to 3
   as the CL Gemm Kernel can only support up to 3 dimensions.

Signed-off-by: Mike Kelly <mike.kelly@arm.com>
Change-Id: I6b3d0886c5b97fdb686838fc3dc292833ddc4643

2 files changed, 92 insertions, 2 deletions

diff --git a/src/armnnUtils/TensorUtils.cpp b/src/armnnUtils/TensorUtils.cpp
index 9e3d719211..03109e0cee 100644
--- a/src/armnnUtils/TensorUtils.cpp
+++ b/src/armnnUtils/TensorUtils.cpp
@@ -1,5 +1,5 @@
 //
-// Copyright © 2017 Arm Ltd. All rights reserved.
+// Copyright © 2017-2023 Arm Ltd. All rights reserved.
 // SPDX-License-Identifier: MIT
 //
 
@@ -103,6 +103,40 @@ std::pair<float, float> FindMinMax(ITensorHandle* tensorHandle)
     return std::make_pair(min, max);
 }
 
+TensorShape ReduceDims(const TensorShape& tensorShape, unsigned int dimensions)
+{
+    if (tensorShape.GetNumDimensions() <= dimensions)
+    {
+        return tensorShape;
+    }
+    std::vector<unsigned int> newShape;
+
+    unsigned int dimsToSkip = tensorShape.GetNumDimensions() - dimensions;
+    unsigned int dimsSkipped = 0;
+    bool insertRemainder = false;
+
+    for (unsigned int i = 0; i < tensorShape.GetNumDimensions(); ++i)
+    {
+        if (tensorShape[i] == 1 && dimsSkipped < dimsToSkip && !insertRemainder)
+        {
+            ++dimsSkipped;
+            continue;
+        }
+        newShape.push_back(tensorShape[i]);
+        // Once we insert the first dimension we can't skip any more
+        insertRemainder = true;
+    }
+    return TensorShape(static_cast<unsigned int>(newShape.size()), newShape.data());
+}
+
+TensorInfo ReduceDims(const TensorInfo& tensorInfo, unsigned int dimensions)
+{
+    TensorInfo strippedTensor(tensorInfo);
+    TensorShape strippedShape = ReduceDims(tensorInfo.GetShape(), dimensions);
+    strippedTensor.SetShape(strippedShape);
+    return strippedTensor;
+}
+
 TensorShape ExpandDims(const TensorShape& tensorShape, int axis)
 {
     unsigned int outputDim = tensorShape.GetNumDimensions() + 1;
diff --git a/src/armnnUtils/test/TensorUtilsTest.cpp b/src/armnnUtils/test/TensorUtilsTest.cpp
index 16349c554e..a69a0098ce 100644
--- a/src/armnnUtils/test/TensorUtilsTest.cpp
+++ b/src/armnnUtils/test/TensorUtilsTest.cpp
@@ -1,5 +1,5 @@
 //
-// Copyright © 2019,2021-2022 Arm Ltd and Contributors. All rights reserved.
+// Copyright © 2019,2021-2023 Arm Ltd and Contributors. All rights reserved.
 // SPDX-License-Identifier: MIT
 //
 
@@ -126,6 +126,62 @@ TEST_CASE("ExpandDimsInvalidAxisTest")
     CHECK_THROWS_AS(ExpandDims(inputShape, 4), armnn::InvalidArgumentException);
 }
 
+TEST_CASE("ReduceDimsShapeAll1s")
+{
+    armnn::TensorShape inputShape({ 1, 1, 1 });
+
+    // Invalid expand dimension 4
+    armnn::TensorShape outputShape = ReduceDims(inputShape, 2);
+    CHECK(outputShape.GetNumDimensions() == 2);
+    CHECK(outputShape[0] == 1);
+    CHECK(outputShape[1] == 1);
+}
+
+TEST_CASE("ReduceDimsShapeNotEnough1s")
+{
+    armnn::TensorShape inputShape({ 1, 2, 1 });
+
+    // Invalid expand dimension 4
+    armnn::TensorShape outputShape = ReduceDims(inputShape, 1);
+    CHECK(outputShape.GetNumDimensions() == 2);
+    CHECK(outputShape[0] == 2);
+    CHECK(outputShape[1] == 1);
+}
+
+TEST_CASE("ReduceDimsInfoAll1s")
+{
+    armnn::TensorInfo inputInfo({ 1, 1, 1 }, DataType::Float32);
+
+    // Invalid expand dimension 4
+    armnn::TensorInfo outputInfo = ReduceDims(inputInfo, 2);
+    CHECK(outputInfo.GetShape().GetNumDimensions() == 2);
+    CHECK(outputInfo.GetShape()[0] == 1);
+    CHECK(outputInfo.GetShape()[1] == 1);
+}
+
+TEST_CASE("ReduceDimsInfoNotEnough1s")
+{
+    armnn::TensorInfo inputInfo({ 1, 2, 1 }, DataType::Float32);
+
+    // Invalid expand dimension 4
+    armnn::TensorInfo outputInfo = ReduceDims(inputInfo, 1);
+    CHECK(outputInfo.GetNumDimensions() == 2);
+    CHECK(outputInfo.GetShape()[0] == 2);
+    CHECK(outputInfo.GetShape()[1] == 1);
+}
+
+TEST_CASE("ReduceDimsShapeDimensionGreaterThanSize")
+{
+    armnn::TensorShape inputShape({ 1, 1, 1 });
+
+    // Invalid expand dimension 4
+    armnn::TensorShape outputShape = ReduceDims(inputShape, 4);
+    CHECK(outputShape.GetNumDimensions() == 3);
+    CHECK(outputShape[0] == 1);
+    CHECK(outputShape[1] == 1);
+    CHECK(outputShape[2] == 1);
+}
+
 TEST_CASE("ExpandDimsInvalidNegativeAxisTest")
 {
     armnn::TensorShape inputShape({ 2, 3, 4 });