COMPMID-731 - Remove padding requirements for NEGEMMLowpOutputStage

Used a left-over for loop in:
- NEGEMMLowpQuantizeDownInt32ToUint8ScaleByFixedPointKernel
- NEGEMMLowpQuantizeDownInt32ToUint8ScaleKernel
in order to remove the padding requirements for AndroidNN

Change-Id: I8ef529fc3d1adecf15fbe42002d99bc0030f131f
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/112266
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
Tested-by: BSG Visual Compute Jenkins server to access repositories on http://mpd-gerrit.cambridge.arm.com <bsgcomp@arm.com>

1 files changed, 114 insertions, 40 deletions

diff --git a/src/core/NEON/kernels/NEGEMMLowpQuantizeDownInt32ToUint8ScaleByFixedPointKernel.cpp b/src/core/NEON/kernels/NEGEMMLowpQuantizeDownInt32ToUint8ScaleByFixedPointKernel.cpp
index 1e369ab03a..8b3f2383ab 100644
--- a/src/core/NEON/kernels/NEGEMMLowpQuantizeDownInt32ToUint8ScaleByFixedPointKernel.cpp
+++ b/src/core/NEON/kernels/NEGEMMLowpQuantizeDownInt32ToUint8ScaleByFixedPointKernel.cpp
@@ -66,7 +66,10 @@ Status validate_arguments(const ITensorInfo *input, const ITensorInfo *bias, con
 
 std::pair<Status, Window> validate_and_configure_window(ITensorInfo *input, ITensorInfo *bias, ITensorInfo *output)
 {
-    constexpr unsigned int num_elems_processed_per_iteration = 16;
+    // Note: This kernel performs 16 elements per iteration.
+    // However, since we use a left-over for loop, we cannot have any read or write out of memory
+    // For this reason num_elems_processed_per_iteration is set to 1
+    constexpr unsigned int num_elems_processed_per_iteration = 1;
 
     // Configure kernel window
     Window win = calculate_max_window(*output, Steps(num_elems_processed_per_iteration));
@@ -86,7 +89,7 @@ std::pair<Status, Window> validate_and_configure_window(ITensorInfo *input, ITen
 
     if(bias != nullptr)
     {
-        AccessWindowStatic bias_access(bias, 0, 0, ceil_to_multiple(bias->dimension(0), num_elems_processed_per_iteration), bias->tensor_shape()[1]);
+        AccessWindowStatic bias_access(bias, 0, 0, bias->dimension(0), bias->dimension(1));
         window_changed = window_changed || update_window_and_padding(win, bias_access);
     }
 
@@ -144,6 +147,37 @@ inline uint8x16_t finalize_quantization(int32x4x4_t &in_s32, int result_fixedpoi
 
     return out_u8;
 }
+
+/* Function used by the left-over for loop to perform the quantization */
+template <bool is_bounded_relu>
+inline uint8_t finalize_quantization(int32x4_t in_s32, int result_fixedpoint_multiplier, int32_t result_shift, int32x4_t result_offset_after_shift_s32, uint8_t min_u8, uint8_t max_u8)
+{
+    const static int32x4_t zero_s32      = vdupq_n_s32(0);
+    const static int32x4_t sat_value_s32 = vdupq_n_s32(255);
+
+    // Fixed point multiplication with vector saturating rounding doubling multiply high with scalar
+    in_s32 = vqrdmulhq_n_s32(in_s32, result_fixedpoint_multiplier);
+
+    // Round to the nearest division by a power-of-two using result_shift_s32
+    in_s32 = rounding_divide_by_pow2(in_s32, result_shift);
+
+    // Add the offset terms
+    in_s32 = vaddq_s32(in_s32, result_offset_after_shift_s32);
+
+    // Saturate negative values
+    in_s32 = vmaxq_s32(in_s32, zero_s32);
+    in_s32 = vminq_s32(in_s32, sat_value_s32);
+
+    auto out_u8 = static_cast<uint8_t>(vgetq_lane_s32(in_s32, 0));
+
+    if(is_bounded_relu)
+    {
+        out_u8 = std::max(out_u8, min_u8);
+        out_u8 = std::min(out_u8, max_u8);
+    }
+
+    return out_u8;
+}
 } // namespace
 
 namespace arm_compute
@@ -161,63 +195,103 @@ void NEGEMMLowpQuantizeDownInt32ToUint8ScaleByFixedPointKernel::run(const Window
     ARM_COMPUTE_UNUSED(min_u8);
     ARM_COMPUTE_UNUSED(max_u8);
 
-    Iterator in(_input, window);
-    Iterator out(_output, window);
+    const int  window_step_x  = 16;
+    const auto window_start_x = static_cast<int>(window.x().start());
+    const auto window_end_x   = static_cast<int>(window.x().end());
+
+    Window win(window);
+    win.set(Window::DimX, Window::Dimension(0, 1, 1));
+
+    Iterator in(_input, win);
+    Iterator out(_output, win);
 
     if(_bias != nullptr)
     {
         Window win_biases;
-        win_biases.set(Window::DimX, Window::Dimension(window.x().start(), window.x().end(), window.x().step()));
+        win_biases.set(Window::DimX, Window::Dimension(0, 1, 1));
         win_biases.set(Window::DimY, Window::Dimension(0, 1, 1));
 
         Iterator bias(_bias, win_biases);
-        execute_window_loop(window, [&](const Coordinates & id)
+        execute_window_loop(win, [&](const Coordinates & id)
         {
-            int32x4x4_t in_s32 =
+            // Compute 16 elements per iteration
+            int x = window_start_x;
+            for(; x <= (window_end_x - window_step_x); x += window_step_x)
             {
+                int32x4x4_t in_s32 =
                 {
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 0),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 4),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 8),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 12)
-                }
-            };
-
-            const int32x4x4_t bias_s32 =
-            {
+                    {
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 0),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 4),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 8),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 12)
+                    }
+                };
+
+                const int32x4x4_t bias_s32 =
                 {
-                    vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + 0),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + 4),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + 8),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + 12)
-                }
-            };
-
-            // Add the bias to GEMM's result
-            in_s32.val[0] = vaddq_s32(in_s32.val[0], bias_s32.val[0]);
-            in_s32.val[1] = vaddq_s32(in_s32.val[1], bias_s32.val[1]);
-            in_s32.val[2] = vaddq_s32(in_s32.val[2], bias_s32.val[2]);
-            in_s32.val[3] = vaddq_s32(in_s32.val[3], bias_s32.val[3]);
-
-            vst1q_u8(out.ptr(), finalize_quantization<is_bounded_relu>(in_s32, _result_fixedpoint_multiplier, _result_shift, result_offset_after_shift_s32, min_u8, max_u8));
+                    {
+                        vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + x + 0),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + x + 4),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + x + 8),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(bias.ptr()) + x + 12)
+                    }
+                };
+
+                // Add the bias to GEMM's result
+                in_s32.val[0] = vaddq_s32(in_s32.val[0], bias_s32.val[0]);
+                in_s32.val[1] = vaddq_s32(in_s32.val[1], bias_s32.val[1]);
+                in_s32.val[2] = vaddq_s32(in_s32.val[2], bias_s32.val[2]);
+                in_s32.val[3] = vaddq_s32(in_s32.val[3], bias_s32.val[3]);
+
+                vst1q_u8(out.ptr() + x, finalize_quantization<is_bounded_relu>(in_s32, _result_fixedpoint_multiplier, _result_shift, result_offset_after_shift_s32, min_u8, max_u8));
+            }
+
+            // Compute left-over elements
+            for(; x < window_end_x; ++x)
+            {
+                const int32_t bias_value = *(reinterpret_cast<const int32_t *>(bias.ptr()) + x);
+                int32_t       in_value   = *(reinterpret_cast<const int32_t *>(in.ptr()) + x);
+
+                // Add bias
+                in_value += bias_value;
+
+                // Finalize and store the result
+                *(out.ptr() + x) = finalize_quantization<is_bounded_relu>(vdupq_n_s32(in_value), _result_fixedpoint_multiplier, _result_shift, result_offset_after_shift_s32, static_cast<uint8_t>(_min),
+                                                                          static_cast<uint8_t>(_max));
+            }
         },
         in, bias, out);
     }
     else
     {
-        execute_window_loop(window, [&](const Coordinates & id)
+        execute_window_loop(win, [&](const Coordinates & id)
         {
-            int32x4x4_t in_s32 =
+            // Compute 16 elements per iteration
+            int x = window_start_x;
+            for(; x <= (window_end_x - window_step_x); x += window_step_x)
             {
+                int32x4x4_t in_s32 =
                 {
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 0),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 4),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 8),
-                    vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + 12)
-                }
-            };
-
-            vst1q_u8(out.ptr(), finalize_quantization<is_bounded_relu>(in_s32, _result_fixedpoint_multiplier, _result_shift, result_offset_after_shift_s32, min_u8, max_u8));
+                    {
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 0),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 4),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 8),
+                        vld1q_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x + 12)
+                    }
+                };
+
+                vst1q_u8(out.ptr() + x, finalize_quantization<is_bounded_relu>(in_s32, _result_fixedpoint_multiplier, _result_shift, result_offset_after_shift_s32, min_u8, max_u8));
+            }
+
+            // Compute left-over elements
+            for(; x < window_end_x; ++x)
+            {
+                const int32x4_t in_s32 = vld1q_dup_s32(reinterpret_cast<const int32_t *>(in.ptr()) + x);
+
+                // Finalize and store the result
+                *(out.ptr() + x) = finalize_quantization<is_bounded_relu>(in_s32, _result_fixedpoint_multiplier, _result_shift, result_offset_after_shift_s32, static_cast<uint8_t>(_min), static_cast<uint8_t>(_max));
+            }
         },
         in, out);
     }