COMPMID-2063: New Winograd implementation

Refactoring of winograd code reducing the size of the binaries
about 8X.

Change-Id: If8845bda324573e1a5cf436f354ac8603e88a92e
Signed-off-by: Pablo Tello <pablo.tello@arm.com>
Reviewed-on: https://review.mlplatform.org/c/959
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Anthony Barbier <Anthony.barbier@arm.com>
Reviewed-by: Georgios Pinitas <georgios.pinitas@arm.com>
diff --git a/src/core/NEON/kernels/convolution/winograd/winograd_transforms/output_2_7_fp32_fp32_integers.cpp b/src/core/NEON/kernels/convolution/winograd/winograd_transforms/output_2_7_fp32_fp32_integers.cpp
new file mode 100644
index 0000000..c32d7f2
--- /dev/null
+++ b/src/core/NEON/kernels/convolution/winograd/winograd_transforms/output_2_7_fp32_fp32_integers.cpp
@@ -0,0 +1,137 @@
+/*
+ * Copyright (c) 2019 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 "arm.hpp"
+#include "output.hpp"
+
+namespace winograd
+{
+
+template <>
+void OutputTransform<1, 7, 1, 8, float, float, WinogradRoots::Integers>::transform_tile(
+  const int n_channels,
+  const float* inptr,
+  const int matrix_stride,
+  const float* bptr,
+  float* const output,
+  const int,  // No need to stride across rows
+  const int output_col_stride
+)
+{
+  // Construct a map to the output cells
+  float *outptrs[output_tile_cols];
+  for (int j = 0; j < output_tile_cols; j++)
+  {
+    outptrs[j] = output + j*output_col_stride;
+  }
+
+  // For each channel of the output
+  int channels_remaining = n_channels;
+#ifdef __arm_any__
+  for (; channels_remaining >= 4; channels_remaining -= 4)
+  {
+    // Matrices used and computed during this transform
+    float32x4_t F[inner_tile_cols], f[output_tile_cols], b = vdupq_n_f32(0.0f);
+
+    // Read a 1x8 tile in the Winograd domain
+    for (int j = 0; j < inner_tile_cols; j++)
+    {
+      F[j] = vld1q_f32(inptr + j*matrix_stride);
+    }
+    inptr += 4;
+
+    f[0] = vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmulq_n_f32(F[6], 1), F[5], 1), F[4], 1), F[3], 1), F[2], 1), F[1], 1), F[0], 1);
+    f[1] = vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmlaq_n_f32(vmulq_n_f32(F[7], 1), F[2], 1), F[6], 3), F[4], 2), F[3], -2), F[5], -3), F[1], -1);
+
+    // Write out the output tile
+    if (bptr != 0)
+    {
+      b = vld1q_f32(bptr);
+      bptr += 4;
+    }
+    for (int j = 0; j < output_tile_cols; j++)
+    {
+      vst1q_f32(outptrs[j], f[j] + b);
+      outptrs[j] += 4;
+    }
+  }
+  for (; channels_remaining >= 2; channels_remaining -= 2)
+  {
+    // Matrices used and computed during this transform
+    float32x2_t F[inner_tile_cols], f[output_tile_cols], b = vdup_n_f32(0.0f);
+
+    // Read a 1x8 tile in the Winograd domain
+    for (int j = 0; j < inner_tile_cols; j++)
+    {
+      F[j] = vld1_f32(inptr + j*matrix_stride);
+    }
+    inptr += 2;
+
+    f[0] = vmla_n_f32(vmla_n_f32(vmla_n_f32(vmla_n_f32(vmla_n_f32(vmla_n_f32(vmul_n_f32(F[6], 1), F[5], 1), F[4], 1), F[3], 1), F[2], 1), F[1], 1), F[0], 1);
+    f[1] = vmla_n_f32(vmla_n_f32(vmla_n_f32(vmla_n_f32(vmla_n_f32(vmla_n_f32(vmul_n_f32(F[7], 1), F[2], 1), F[6], 3), F[4], 2), F[3], -2), F[5], -3), F[1], -1);
+
+    // Write out the output tile
+    if (bptr != 0)
+    {
+      b = vld1_f32(bptr);
+      bptr += 2;
+    }
+    for (int j = 0; j < output_tile_cols; j++)
+    {
+      vst1_f32(outptrs[j], f[j] + b);
+      outptrs[j] += 2;
+    }
+  }
+#endif  // __arm_any__
+  for (; channels_remaining; channels_remaining--)
+  {
+    // Matrices used and computed during this transform
+    float F[inner_tile_cols], f[output_tile_cols], b = 0.0f;
+
+    // Read a 1x8 tile in the Winograd domain
+    for (int j = 0; j < inner_tile_cols; j++)
+    {
+      F[j] = *(inptr + j*matrix_stride);
+    }
+    inptr++;
+
+    f[0] = F[0]*1 + F[1]*1 + F[2]*1 + F[3]*1 + F[4]*1 + F[5]*1 + F[6]*1;
+    f[1] = F[1]*-1 + F[5]*-3 + F[3]*-2 + F[4]*2 + F[6]*3 + F[2]*1 + F[7]*1;
+
+    // Write out the output tile
+    if (bptr != 0)
+    {
+      b = *(bptr++);
+    }
+    for (int j = 0; j < output_tile_cols; j++)
+    {
+      *(outptrs[j]++) = f[j] + b;
+    }
+  }
+}
+
+template class OutputTransform<1, 7, 1, 8, float, float, WinogradRoots::Integers>;
+template class OutputTransform<7, 1, 8, 1, float, float, WinogradRoots::Integers>;
+
+}  // namespace winograd