Integrate improved CPU depthwise convolution kernels

* Replace assembly kernels for depthwise convolution with more optimized
  ones.
* Add int8 assembly kernels.
* Fix implicit padding on optimized kernels

Resolves: COMPMID-3867, COMPMID-4361

Change-Id: I0b0867e05f61be4f368f62190d55e14d0ab3ebf2
Signed-off-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/5622
Tested-by: Arm Jenkins <bsgcomp@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
diff --git a/src/core/cpu/kernels/internal/CpuDepthwiseConv2dAssemblyWrapperKernel.cpp b/src/core/cpu/kernels/internal/CpuDepthwiseConv2dAssemblyWrapperKernel.cpp
new file mode 100644
index 0000000..f5c63b7
--- /dev/null
+++ b/src/core/cpu/kernels/internal/CpuDepthwiseConv2dAssemblyWrapperKernel.cpp
@@ -0,0 +1,359 @@
+/*
+ * Copyright (c) 2021 Arm Limited.
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+#include "src/core/cpu/kernels/internal/CpuDepthwiseConv2dAssemblyWrapperKernel.h"
+
+#include "arm_compute/core/Utils.h"
+#include "arm_compute/core/Validate.h"
+#include "arm_compute/core/utils/misc/ShapeCalculator.h"
+#include "arm_compute/core/utils/quantization/AsymmHelpers.h"
+#include "src/core/CPP/Validate.h"
+#include "src/core/helpers/AutoConfiguration.h"
+#include "src/core/helpers/WindowHelpers.h"
+#include "src/core/utils/AssemblyUtils.h"
+
+#include "src/core/NEON/kernels/assembly/depthwise.hpp"
+
+#include "depthwise_common.hpp"
+
+#include <arm_neon.h>
+
+namespace arm_compute
+{
+namespace cpu
+{
+namespace kernels
+{
+using namespace arm_compute::misc::shape_calculator;
+
+namespace
+{
+constexpr unsigned int idx_width    = 1;
+constexpr unsigned int idx_height   = 2;
+constexpr unsigned int idx_channels = 0;
+constexpr unsigned int idx_batches  = 3;
+
+template <typename TSrc, typename TWeights, typename TDst>
+void create_arm_dwc(const ITensorInfo *src, const ITensorInfo *weights, ITensorInfo *dst,
+                    const ConvolutionInfo &info, const CPUInfo &cpu_info,
+                    std::unique_ptr<arm_conv::depthwise::IDepthwiseCommon> &kernel)
+{
+    unsigned int stride_cols{};
+    unsigned int stride_rows{};
+    std::tie(stride_cols, stride_rows) = info.pad_stride_info.stride();
+
+    const arm_conv::PaddingValues padding = assembly_utils::map_to_arm_conv_padding(info.pad_stride_info);
+
+    const unsigned int n_batches  = src->dimension(idx_batches);
+    const unsigned int src_rows   = src->dimension(idx_height);
+    const unsigned int src_cols   = src->dimension(idx_width);
+    const unsigned int n_channels = src->dimension(idx_channels);
+    const unsigned int dst_rows   = dst->dimension(idx_height);
+    const unsigned int dst_cols   = dst->dimension(idx_width);
+
+    const unsigned int kernel_cols = weights->dimension(idx_width);
+    const unsigned int kernel_rows = weights->dimension(idx_height);
+
+    const arm_gemm::Activation activation = assembly_utils::map_to_arm_gemm_activation(info.act_info);
+
+    arm_conv::depthwise::DepthwiseArgs args(&cpu_info, kernel_rows, kernel_cols, stride_rows, stride_cols,
+                                            n_batches, src_rows, src_cols, n_channels, dst_rows, dst_cols, info.depth_multiplier,
+                                            padding, activation, nullptr);
+
+    // Configure assembly pooling kernel
+    auto dwc_kernel_asm = arm_conv::depthwise::depthwise<TSrc, TWeights, TDst>(args);
+    if(dwc_kernel_asm == nullptr)
+    {
+        // Configuration not supported: Leave function unconfigured:
+        return;
+    }
+
+    kernel = std::move(dwc_kernel_asm);
+}
+
+template <typename TSrc, typename TWeights, typename TDst>
+void create_arm_dwc_quant(const ITensorInfo *src, const ITensorInfo *weights, ITensorInfo *dst,
+                          const ConvolutionInfo &info, const CPUInfo &cpu_info,
+                          std::unique_ptr<arm_conv::depthwise::IDepthwiseCommon> &kernel,
+                          std::vector<int32_t> &multipliers, std::vector<int32_t> &right_shifts, std::vector<int32_t> &left_shifts)
+{
+    unsigned int stride_cols{};
+    unsigned int stride_rows{};
+    std::tie(stride_cols, stride_rows) = info.pad_stride_info.stride();
+
+    const arm_conv::PaddingValues padding = assembly_utils::map_to_arm_conv_padding(info.pad_stride_info);
+
+    const unsigned int n_batches  = src->dimension(idx_batches);
+    const unsigned int src_rows   = src->dimension(idx_height);
+    const unsigned int src_cols   = src->dimension(idx_width);
+    const unsigned int n_channels = src->dimension(idx_channels);
+    const unsigned int dst_rows   = dst->dimension(idx_height);
+    const unsigned int dst_cols   = dst->dimension(idx_width);
+
+    const unsigned int kernel_cols = weights->dimension(idx_width);
+    const unsigned int kernel_rows = weights->dimension(idx_height);
+
+    const arm_gemm::Activation activation = assembly_utils::map_to_arm_gemm_activation(info.act_info);
+
+    arm_conv::depthwise::DepthwiseArgs args(&cpu_info, kernel_rows, kernel_cols, stride_rows, stride_cols,
+                                            n_batches, src_rows, src_cols, n_channels, dst_rows, dst_cols, info.depth_multiplier,
+                                            padding, activation, nullptr);
+
+    const auto src_qinfo     = src->quantization_info().uniform();
+    const auto weights_qinfo = weights->quantization_info();
+    const auto dst_qinfo     = dst->quantization_info().uniform();
+
+    const unsigned int num_filters = weights_qinfo.scale().size();
+
+    multipliers.resize(num_filters);
+    std::vector<int32_t> dst_shifts(num_filters);
+    quantization::compute_quantized_multipliers_and_shifts(src,
+                                                           weights,
+                                                           dst,
+                                                           multipliers.data(),
+                                                           dst_shifts.data());
+
+    // Quantize activation bounds
+    int32_t min_activation = std::numeric_limits<TSrc>::lowest();
+    int32_t max_activation = std::numeric_limits<TSrc>::max();
+    if(info.act_info.enabled())
+    {
+        std::tie(min_activation, max_activation) = get_quantized_activation_min_max(info.act_info, src->data_type(), dst_qinfo);
+    }
+
+    // Set quantization parameters for assembly kernels
+    arm_gemm::Requantize32 requant_args{};
+    if(is_data_type_quantized_per_channel(weights->data_type()))
+    {
+        left_shifts.resize(num_filters);
+        right_shifts.resize(num_filters);
+        bool need_left_shift = false; // Select more optimized path if left shift is not needed
+        for(unsigned int i = 0; i < num_filters; ++i)
+        {
+            left_shifts[i]  = std::max(-dst_shifts[i], static_cast<int32_t>(0));
+            right_shifts[i] = std::min(-dst_shifts[i], static_cast<int32_t>(0));
+            if(dst_shifts[i] < 0 && !need_left_shift)
+            {
+                need_left_shift = true;
+            }
+        }
+
+        requant_args = arm_gemm::Requantize32(nullptr,
+                                              0,
+                                              src_qinfo.offset,
+                                              weights_qinfo.uniform().offset,
+                                              dst_qinfo.offset,
+                                              (need_left_shift) ? left_shifts.data() : nullptr,
+                                              right_shifts.data(),
+                                              multipliers.data(),
+                                              static_cast<TSrc>(min_activation),
+                                              static_cast<TSrc>(max_activation));
+    }
+    else
+    {
+        requant_args = arm_gemm::Requantize32(nullptr,
+                                              0,
+                                              src_qinfo.offset,
+                                              weights_qinfo.uniform().offset,
+                                              dst_qinfo.offset,
+                                              -dst_shifts[0],
+                                              multipliers[0],
+                                              static_cast<TSrc>(min_activation),
+                                              static_cast<TSrc>(max_activation));
+    }
+
+    // Configure assembly pooling kernel with requantization
+    auto dwc_kernel_asm = arm_conv::depthwise::depthwise<TSrc, TWeights, TDst, arm_gemm::Requantize32>(args, requant_args);
+    if(dwc_kernel_asm == nullptr)
+    {
+        // Configuration not supported: Leave function unconfigured:
+        return;
+    }
+
+    kernel = std::move(dwc_kernel_asm);
+}
+} // namespace
+
+CpuDepthwiseConv2dAssemblyWrapperKernel::CpuDepthwiseConv2dAssemblyWrapperKernel()
+    : _kernel_asm(nullptr),
+      _multipliers(),
+      _left_shifts(),
+      _right_shifts()
+{
+}
+
+CpuDepthwiseConv2dAssemblyWrapperKernel::~CpuDepthwiseConv2dAssemblyWrapperKernel() = default;
+
+void CpuDepthwiseConv2dAssemblyWrapperKernel::configure(const ITensorInfo *src, const ITensorInfo *weights, const ITensorInfo *, ITensorInfo *dst,
+                                                        const ConvolutionInfo &info, const CPUInfo &cpu_info)
+{
+    ARM_COMPUTE_UNUSED(cpu_info);
+    ARM_COMPUTE_ERROR_ON_NULLPTR(src, weights, dst);
+
+    // Destination initialization if not yet initialized
+    const TensorShape dst_shape = compute_depthwise_convolution_shape(*src, *weights, info);
+    auto_init_if_empty(*dst, src->clone()->set_tensor_shape(dst_shape));
+
+#if defined(__aarch64__)
+    switch(src->data_type())
+    {
+        case DataType::QASYMM8:
+            if(is_data_type_quantized_per_channel(weights->data_type()))
+            {
+                create_arm_dwc_quant<uint8_t, int8_t, uint8_t>(src, weights, dst, info, cpu_info, _kernel_asm, _multipliers, _right_shifts, _left_shifts);
+            }
+            else
+            {
+                create_arm_dwc_quant<uint8_t, uint8_t, uint8_t>(src, weights, dst, info, cpu_info, _kernel_asm, _multipliers, _right_shifts, _left_shifts);
+            }
+            break;
+        case DataType::QASYMM8_SIGNED:
+            create_arm_dwc_quant<int8_t, int8_t, int8_t>(src, weights, dst, info, cpu_info, _kernel_asm, _multipliers, _right_shifts, _left_shifts);
+            break;
+#if defined(__ARM_FEATURE_FP16_VECTOR_ARITHMETIC)
+        case DataType::F16:
+            create_arm_dwc<float16_t, float16_t, float16_t>(src, weights, dst, info, cpu_info, _kernel_asm);
+            break;
+#endif // defined(__ARM_FEATURE_FP16_VECTOR_ARITHMETIC)
+        case DataType::F32:
+            create_arm_dwc<float, float, float>(src, weights, dst, info, cpu_info, _kernel_asm);
+            break;
+        default:
+            break;
+    }
+#endif // defined(__aarch64__)
+
+    Window win = calculate_max_window(*dst, Steps());
+    ICpuKernel::configure(win);
+}
+
+Status CpuDepthwiseConv2dAssemblyWrapperKernel::validate(const ITensorInfo *src, const ITensorInfo *weights, const ITensorInfo *bias, const ITensorInfo *dst, const ConvolutionInfo &info)
+{
+    ARM_COMPUTE_RETURN_ERROR_ON_NULLPTR(src, dst);
+
+#if !defined(__aarch64__)
+    ARM_COMPUTE_RETURN_ERROR_MSG("32-bit is not supported by assembly kernels");
+#endif // !defined(__aarch64__)
+    ARM_COMPUTE_RETURN_ERROR_ON_CPU_F16_UNSUPPORTED(src);
+    ARM_COMPUTE_RETURN_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(src, 1, DataType::QASYMM8, DataType::QASYMM8_SIGNED, DataType::F16, DataType::F32);
+    ARM_COMPUTE_RETURN_ERROR_ON_MSG(src->data_layout() != DataLayout::NHWC, "Only NHWC is supported by assembly kernels");
+    ARM_COMPUTE_RETURN_ERROR_ON_MSG(info.dilation != Size2D(1, 1), "Assembly kernels do not support dilation != (1, 1)");
+
+    if(is_data_type_quantized_per_channel(weights->data_type()))
+    {
+        ARM_COMPUTE_RETURN_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(weights, 1, DataType::QSYMM8_PER_CHANNEL);
+        ARM_COMPUTE_RETURN_ERROR_ON(weights->dimension(0) != weights->quantization_info().scale().size());
+    }
+    else
+    {
+        ARM_COMPUTE_RETURN_ERROR_ON_MISMATCHING_DATA_TYPES(src, weights);
+    }
+
+    if(bias != nullptr)
+    {
+        ARM_COMPUTE_RETURN_ERROR_ON(bias->num_dimensions() > 1);
+        ARM_COMPUTE_RETURN_ERROR_ON(bias->dimension(0) != weights->dimension(0));
+
+        if(is_data_type_quantized(src->data_type()))
+        {
+            ARM_COMPUTE_RETURN_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(bias, 1, DataType::S32);
+        }
+        else
+        {
+            ARM_COMPUTE_RETURN_ERROR_ON_MISMATCHING_DATA_TYPES(src, bias);
+        }
+    }
+
+    if(dst->total_size() > 0)
+    {
+        const TensorShape dst_shape = misc::shape_calculator::compute_depthwise_convolution_shape(*src, *weights, info);
+        ARM_COMPUTE_RETURN_ERROR_ON_MISMATCHING_DIMENSIONS(dst->tensor_shape(), dst_shape);
+        ARM_COMPUTE_RETURN_ERROR_ON_MISMATCHING_DATA_TYPES(src, dst);
+    }
+    return Status{};
+}
+
+void CpuDepthwiseConv2dAssemblyWrapperKernel::run_op(ITensorPack &tensors, const Window &window, const ThreadInfo &info)
+{
+    ARM_COMPUTE_ERROR_ON_NULLPTR(_kernel_asm.get());
+    ARM_COMPUTE_ERROR_ON_UNCONFIGURED_KERNEL(this);
+    ARM_COMPUTE_UNUSED(window);
+    ARM_COMPUTE_UNUSED(info);
+
+    ARM_COMPUTE_ERROR_ON(tensors.empty());
+
+    const ITensor *src       = tensors.get_const_tensor(TensorType::ACL_SRC_0);
+    ITensor       *dst       = tensors.get_tensor(TensorType::ACL_DST);
+    ITensor       *workspace = tensors.get_tensor(TensorType::ACL_INT_0);
+    ITensor       *storage   = tensors.get_tensor(TensorType::ACL_INT_1);
+
+    const auto src_ptr        = src->buffer() + src->info()->offset_first_element_in_bytes();
+    auto       dst_ptr        = dst->buffer() + dst->info()->offset_first_element_in_bytes();
+    auto       working_space  = workspace->buffer() + workspace->info()->offset_first_element_in_bytes();
+    auto       parameters_ptr = storage->buffer() + storage->info()->offset_first_element_in_bytes();
+
+    const auto src_shape   = src->info()->tensor_shape();
+    const auto dst_shape   = dst->info()->tensor_shape();
+    const auto src_padding = src->info()->padding();
+    const auto dst_padding = dst->info()->padding();
+
+    const size_t ld_src_col   = src_shape[0] + src_padding.left + src_padding.right;
+    const size_t ld_src_row   = ld_src_col * (src_shape[1] + src_padding.top + src_padding.bottom);
+    const size_t ld_src_batch = ld_src_row * src_shape[2];
+    const size_t ld_dst_col   = dst_shape[0] + dst_padding.left + dst_padding.right;
+    const size_t ld_dst_row   = ld_dst_col * (dst_shape[1] + dst_padding.top + dst_padding.bottom);
+    const size_t ld_dst_batch = ld_dst_row * dst_shape[2];
+
+    _kernel_asm->execute(src_ptr, ld_src_col, ld_src_row, ld_src_batch,
+                         parameters_ptr,
+                         dst_ptr, ld_dst_col, ld_dst_row, ld_dst_batch,
+                         working_space, info.thread_id, info.num_threads);
+}
+
+void CpuDepthwiseConv2dAssemblyWrapperKernel::pack_parameters(void *parameters_ptr, void *bias_ptr, void *weights_ptr, size_t ld_weights_col, size_t ld_weight_row)
+{
+    _kernel_asm->pack_parameters(parameters_ptr, bias_ptr, weights_ptr, ld_weights_col, ld_weight_row);
+}
+
+size_t CpuDepthwiseConv2dAssemblyWrapperKernel::get_storage_size() const
+{
+    return _kernel_asm->get_storage_size();
+}
+
+size_t CpuDepthwiseConv2dAssemblyWrapperKernel::get_working_size(unsigned int num_threads, unsigned int num_input_channels) const
+{
+    return _kernel_asm->get_working_size(num_threads, num_input_channels);
+}
+
+bool CpuDepthwiseConv2dAssemblyWrapperKernel::is_configured() const
+{
+    return _kernel_asm != nullptr;
+}
+
+const char *CpuDepthwiseConv2dAssemblyWrapperKernel::name() const
+{
+    return "CpuDepthwiseConv2dAssemblyWrapperKernel";
+}
+} // namespace kernels
+} // namespace cpu
+} // namespace arm_compute