COMPMID-427: Port NEActivationLayer in 16bit fixed point.

Change-Id: Iebd61807f7b597c6bd990673bc7655c68ee16f4b
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/79085
Reviewed-by: Moritz Pflanzer <moritz.pflanzer@arm.com>
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>
Reviewed-by: Gian Marco Iodice <gianmarco.iodice@arm.com>

5 files changed, 71 insertions, 43 deletions

diff --git a/arm_compute/core/FixedPoint.h b/arm_compute/core/FixedPoint.h
index 5eb4c55c41..774125ec7d 100644
--- a/arm_compute/core/FixedPoint.h
+++ b/arm_compute/core/FixedPoint.h
@@ -251,7 +251,16 @@ qint16_t sdiv_qs16(qint16_t a, qint16_t b, int fixed_point_position);
 *
 * @return The result of the 8 bit fixed point exponential.
 */
-qint8_t sexp_qs8(qint8_t a, int fixed_point_position);
+qint8_t sqexp_qs8(qint8_t a, int fixed_point_position);
+
+/** 16 bit fixed point scalar exponential
+*
+* @param[in] a                    16 bit fixed point input
+* @param[in] fixed_point_position Fixed point position that expresses the number of bits for the fractional part of the number
+*
+* @return The result of the 16 bit fixed point exponential.
+*/
+qint16_t sqexp_qs16(qint16_t a, int fixed_point_position);
 
 /** 16 bit fixed point scalar exponential
 *
diff --git a/arm_compute/core/NEON/NEFixedPoint.h b/arm_compute/core/NEON/NEFixedPoint.h
index e3eb5d4638..e30509cd0a 100644
--- a/arm_compute/core/NEON/NEFixedPoint.h
+++ b/arm_compute/core/NEON/NEFixedPoint.h
@@ -176,6 +176,14 @@ void vst1q_qs8(qint8_t *addr, qint8x16_t b);
 */
 void vst1q_qs16(qint16_t *addr, qint16x8_t b);
 
+/** Store two 16 bit fixed point vector to memory (8x2 elements)
+*
+* @param[in] addr Memory address where the 16 bit fixed point vectors should be stored
+* @param[in] b    16 bit fixed point vectors to store
+*
+*/
+void vst2q_qs16(qint16_t *addr, qint16x8x2_t b);
+
 /** 16 bit fixed point vector saturating narrow (8 elements)
  *
  * @param[in] a 16 bit fixed point vector to convert
@@ -1122,7 +1130,7 @@ qint16x8_t vqinvsqrtq_qs16(qint16x8_t a, int fixed_point_position);
  *
  * @return The calculated Hyperbolic Tangent.
  */
-qint8x8_t vtanh_qs8(qint8x8_t a, int fixed_point_position);
+qint8x8_t vqtanh_qs8(qint8x8_t a, int fixed_point_position);
 
 /** Calculate hyperbolic tangent for fixed point 16 bit (4 elements)
  *
@@ -1131,7 +1139,7 @@ qint8x8_t vtanh_qs8(qint8x8_t a, int fixed_point_position);
  *
  * @return The calculated Hyperbolic Tangent.
  */
-qint16x4_t vtanh_qs16(qint16x4_t a, int fixed_point_position);
+qint16x4_t vqtanh_qs16(qint16x4_t a, int fixed_point_position);
 
 /** Calculate hyperbolic tangent for fixed point 8bit (16 elements)
  *
@@ -1140,7 +1148,16 @@ qint16x4_t vtanh_qs16(qint16x4_t a, int fixed_point_position);
  *
  * @return The calculated Hyperbolic Tangent.
  */
-qint8x16_t vtanhq_qs8(qint8x16_t a, int fixed_point_position);
+qint8x16_t vqtanhq_qs8(qint8x16_t a, int fixed_point_position);
+
+/** Calculate hyperbolic tangent for fixed point 16bit (8 elements)
+ *
+ * @param[in] a                    16 bit fixed point input vector
+ * @param[in] fixed_point_position Fixed point position that expresses the number of bits for the fractional part of the number
+ *
+ * @return The calculated Hyperbolic Tangent.
+ */
+qint16x8_t vqtanhq_qs16(qint16x8_t a, int fixed_point_position);
 
 /** Calculate saturating n power for fixed point 8bit (16 elements).
  *
@@ -1162,15 +1179,6 @@ qint8x8_t vqpowq_qs8(qint8x8_t a, qint8x16_t b, int fixed_point_position);
  * @return The lane-by-lane maximum -> float32x4x2
  */
 float32x4x2_t vmax2q_f32(float32x4x2_t a, float32x4x2_t b);
-
-/** Calculate hyperbolic tangent for fixed point 8bit (8 elements)
- *
- * @param[in] a                    16 bit fixed point input vector
- * @param[in] fixed_point_position Fixed point position that expresses the number of bits for the fractional part of the number
- *
- * @return The calculated Hyperbolic Tangent.
- */
-qint16x8_t vtanhq_qs16(qint16x8_t a, int fixed_point_position);
 }
 #include "arm_compute/core/NEON/NEFixedPoint.inl"
 #endif /* __ARM_COMPUTE_NEFIXEDPOINT_H__ */
diff --git a/arm_compute/core/NEON/NEFixedPoint.inl b/arm_compute/core/NEON/NEFixedPoint.inl
index 92af82cf71..b241dd5069 100644
--- a/arm_compute/core/NEON/NEFixedPoint.inl
+++ b/arm_compute/core/NEON/NEFixedPoint.inl
@@ -200,6 +200,11 @@ inline void vst1q_qs16(qint16_t *addr, qint16x8_t b)
     vst1q_s16(addr, b);
 }
 
+inline void vst2q_qs16(qint16_t *addr, qint16x8x2_t b)
+{
+    vst2q_s16(addr, b);
+}
+
 inline qint8x8_t vqmovn_qs16(qint16x8_t a)
 {
     return vqmovn_s16(a);
@@ -1641,15 +1646,15 @@ inline qint8x8_t vqinvsqrt_qs8(qint8x8_t a, int fixed_point_position)
     const qint8x8_t const_three = vdup_n_s8(3 << fixed_point_position);
 
     // Find shift value. Number must be in (0.5, 2) range.
-    qint8x8_t shift_value = vneg_s8(vqsub_s8(vdup_n_s8(8), vqadd_s8(vclz_s8(a), vdup_n_s8(fixed_point_position))));
+    qint8x8_t shift_value = vqneg_s8(vqsub_s8(vdup_n_s8(8), vqadd_s8(vclz_s8(a), vdup_n_s8(fixed_point_position))));
 
     // Add one when the shift value is negative in order to get the correct result when we shift right with 1
     qint8x8_t temp         = vqsub_s8(vdup_n_s8(8), vqadd_s8(vclz_s8(a), vdup_n_s8(fixed_point_position)));
     uint8x8_t temp_ltz     = vclt_s8(temp, vdup_n_qs8(0));
     temp                   = vbsl_s8(temp_ltz, vqadd_s8(temp, vdup_n_s8(1)), temp);
-    qint8x8_t shift_value2 = vneg_s8(vshr_n_s8(temp, 1));
+    qint8x8_t shift_value2 = vqneg_s8(vshr_n_s8(temp, 1));
 
-    temp = vshl_s8(a, shift_value);
+    temp = vqshl_s8(a, shift_value);
 
     // Initial guess
     qint8x8_t x = temp;
@@ -1660,7 +1665,7 @@ inline qint8x8_t vqinvsqrt_qs8(qint8x8_t a, int fixed_point_position)
     x = vshr_n_s8(vqmul_qs8(x, vqsub_s8(const_three, vqmul_qs8(temp, vqmul_qs8(x, x, fixed_point_position), fixed_point_position)), fixed_point_position), 1);
     x = vshr_n_s8(vqmul_qs8(x, vqsub_s8(const_three, vqmul_qs8(temp, vqmul_qs8(x, x, fixed_point_position), fixed_point_position)), fixed_point_position), 1);
 
-    return vshl_s8(x, shift_value2);
+    return vqshl_s8(x, shift_value2);
 }
 
 inline qint16x4_t vqinvsqrt_qs16(qint16x4_t a, int fixed_point_position)
@@ -1668,15 +1673,15 @@ inline qint16x4_t vqinvsqrt_qs16(qint16x4_t a, int fixed_point_position)
     const qint16x4_t const_three = vdup_n_s16(3 << fixed_point_position);
 
     // Find shift value. Number must be in (0.5, 2) range.
-    qint16x4_t shift_value = vneg_s16(vqsub_s16(vdup_n_s16(16), vqadd_s16(vclz_s16(a), vdup_n_s16(fixed_point_position))));
+    qint16x4_t shift_value = vqneg_s16(vqsub_s16(vdup_n_s16(16), vqadd_s16(vclz_s16(a), vdup_n_s16(fixed_point_position))));
 
     // Add one when the shift value is negative in order to get the correct result when we shift right with 1
     qint16x4_t temp         = vqsub_s16(vdup_n_s16(16), vqadd_s16(vclz_s16(a), vdup_n_s16(fixed_point_position)));
     uint16x4_t temp_ltz     = vclt_s16(temp, vdup_n_qs16(0));
     temp                    = vbsl_s16(temp_ltz, vqadd_s16(temp, vdup_n_s16(1)), temp);
-    qint16x4_t shift_value2 = vneg_s16(vshr_n_s16(temp, 1));
+    qint16x4_t shift_value2 = vqneg_s16(vshr_n_s16(temp, 1));
 
-    temp = vshl_s16(a, shift_value);
+    temp = vqshl_s16(a, shift_value);
 
     // Initial guess
     qint16x4_t x = temp;
@@ -1753,15 +1758,15 @@ inline qint8x16_t vqinvsqrtq_qs8(qint8x16_t a, int fixed_point_position)
     const qint8x16_t const_three = vdupq_n_s8(3 << fixed_point_position);
 
     // Find shift value. Number must be in (0.5, 2) range.
-    qint8x16_t shift_value = vnegq_s8(vqsubq_s8(vdupq_n_s8(8), vqaddq_s8(vclzq_s8(a), vdupq_n_s8(fixed_point_position))));
+    qint8x16_t shift_value = vqnegq_s8(vqsubq_s8(vdupq_n_s8(8), vqaddq_s8(vclzq_s8(a), vdupq_n_s8(fixed_point_position))));
 
     // Add one when the shift value is negative in order to get the correct result when we shift right with 1
     qint8x16_t temp         = vqsubq_s8(vdupq_n_s8(8), vqaddq_s8(vclzq_s8(a), vdupq_n_s8(fixed_point_position)));
     uint8x16_t temp_ltz     = vcltq_s8(temp, vdupq_n_qs8(0));
     temp                    = vbslq_s8(temp_ltz, vqaddq_s8(temp, vdupq_n_s8(1)), temp);
-    qint8x16_t shift_value2 = vnegq_s8(vshrq_n_s8(temp, 1));
+    qint8x16_t shift_value2 = vqnegq_s8(vshrq_n_s8(temp, 1));
 
-    temp = vshlq_s8(a, shift_value);
+    temp = vqshlq_s8(a, shift_value);
 
     // Initial guess
     qint8x16_t x = temp;
@@ -1780,13 +1785,13 @@ inline qint16x8_t vqinvsqrtq_qs16(qint16x8_t a, int fixed_point_position)
     const qint16x8_t const_three = vdupq_n_s16(3 << fixed_point_position);
 
     // Find shift value. Number must be in (0.5, 2) range.
-    qint16x8_t shift_value = vnegq_s16(vqsubq_s16(vdupq_n_s16(16), vqaddq_s16(vclzq_s16(a), vdupq_n_s16(fixed_point_position))));
+    qint16x8_t shift_value = vqnegq_s16(vqsubq_s16(vdupq_n_s16(16), vqaddq_s16(vclzq_s16(a), vdupq_n_s16(fixed_point_position))));
 
     // Add one when the shift value is negative in order to get the correct result when we shift right with 1
     qint16x8_t temp         = vqsubq_s16(vdupq_n_s16(16), vqaddq_s16(vclzq_s16(a), vdupq_n_s16(fixed_point_position)));
     uint16x8_t temp_ltz     = vcltq_s16(temp, vdupq_n_qs16(0));
     temp                    = vbslq_s16(temp_ltz, vqaddq_s16(temp, vdupq_n_s16(1)), temp);
-    qint16x8_t shift_value2 = vnegq_s16(vshrq_n_s16(temp, 1));
+    qint16x8_t shift_value2 = vqnegq_s16(vshrq_n_s16(temp, 1));
 
     temp = vqshlq_s16(a, shift_value);
 
@@ -1804,7 +1809,7 @@ inline qint16x8_t vqinvsqrtq_qs16(qint16x8_t a, int fixed_point_position)
     return vqshlq_s16(x, shift_value2);
 }
 
-inline qint8x8_t vtanh_qs8(qint8x8_t a, int fixed_point_position)
+inline qint8x8_t vqtanh_qs8(qint8x8_t a, int fixed_point_position)
 {
     const qint8x8_t const_one = vdup_n_s8(1 << fixed_point_position);
     const qint8x8_t const_two = vdup_n_s8(2 << fixed_point_position);
@@ -1817,7 +1822,7 @@ inline qint8x8_t vtanh_qs8(qint8x8_t a, int fixed_point_position)
     return tanh;
 }
 
-inline qint16x4_t vtanh_qs16(qint16x4_t a, int fixed_point_position)
+inline qint16x4_t vqtanh_qs16(qint16x4_t a, int fixed_point_position)
 {
     const qint16x4_t const_one = vdup_n_s16(1 << fixed_point_position);
     const qint16x4_t const_two = vdup_n_s16(2 << fixed_point_position);
@@ -1830,7 +1835,7 @@ inline qint16x4_t vtanh_qs16(qint16x4_t a, int fixed_point_position)
     return tanh;
 }
 
-inline qint8x16_t vtanhq_qs8(qint8x16_t a, int fixed_point_position)
+inline qint8x16_t vqtanhq_qs8(qint8x16_t a, int fixed_point_position)
 {
     const qint8x16_t const_one = vdupq_n_s8(1 << fixed_point_position);
     const qint8x16_t const_two = vdupq_n_s8(2 << fixed_point_position);
@@ -1843,6 +1848,19 @@ inline qint8x16_t vtanhq_qs8(qint8x16_t a, int fixed_point_position)
     return tanh;
 }
 
+inline qint16x8_t vqtanhq_qs16(qint16x8_t a, int fixed_point_position)
+{
+    const qint16x8_t const_one = vdupq_n_s16(1 << fixed_point_position);
+    const qint16x8_t const_two = vdupq_n_s16(2 << fixed_point_position);
+
+    qint16x8_t exp2x = vqexpq_qs16(vqmulq_qs16(const_two, a, fixed_point_position), fixed_point_position);
+    qint16x8_t num   = vqsubq_qs16(exp2x, const_one);
+    qint16x8_t den   = vqaddq_qs16(exp2x, const_one);
+    qint16x8_t tanh  = vqmulq_qs16(num, vqrecipq_qs16(den, fixed_point_position), fixed_point_position);
+
+    return tanh;
+}
+
 inline qint8x16_t vqpowq_qs8(qint8x16_t a, qint8x16_t b, int fixed_point_position)
 {
     return vqexpq_qs8(vqmulq_qs8(b, vlogq_qs8(a, fixed_point_position), fixed_point_position), fixed_point_position);
@@ -1859,17 +1877,4 @@ inline float32x4x2_t vmax2q_f32(float32x4x2_t a, float32x4x2_t b)
     };
     return res;
 }
-
-inline qint16x8_t vtanhq_qs16(qint16x8_t a, int fixed_point_position)
-{
-    const qint16x8_t const_one = vdupq_n_s16(1 << fixed_point_position);
-    const qint16x8_t const_two = vdupq_n_s16(2 << fixed_point_position);
-
-    qint16x8_t exp2x = vqexpq_qs16(vqmulq_qs16(const_two, a, fixed_point_position), fixed_point_position);
-    qint16x8_t num   = vqsubq_qs16(exp2x, const_one);
-    qint16x8_t den   = vqaddq_qs16(exp2x, const_one);
-    qint16x8_t tanh  = vqmulq_qs16(num, vqrecipq_qs16(den, fixed_point_position), fixed_point_position);
-
-    return tanh;
-}
 }
diff --git a/arm_compute/core/NEON/kernels/NEActivationLayerKernel.h b/arm_compute/core/NEON/kernels/NEActivationLayerKernel.h
index 539bca587a..e995f1e5e0 100644
--- a/arm_compute/core/NEON/kernels/NEActivationLayerKernel.h
+++ b/arm_compute/core/NEON/kernels/NEActivationLayerKernel.h
@@ -50,7 +50,7 @@ public:
      * @note If the output tensor is a nullptr, the activation function will be performed in-place
      *
      * @param[in, out] input           Source tensor. In case of @p output tensor = nullptr, this tensor will store the result
-     *                                 of the activation function. Data types supported: QS8/F32.
+     *                                 of the activation function. Data types supported: QS8/QS16/F32.
      * @param[out]     output          Destination tensor. Data type supported: same as @p input
      * @param[in]      activation_info Activation layer information.
      */
@@ -78,6 +78,12 @@ private:
      */
     template <ActivationLayerInfo::ActivationFunction F, typename T>
     typename std::enable_if<std::is_same<T, qint8_t>::value, void>::type activation(const Window &window);
+    /** Function to apply an activation function on a tensor.
+     *
+     *  @param[in] window Region on which to execute the kernel
+     */
+    template <ActivationLayerInfo::ActivationFunction F, typename T>
+    typename std::enable_if<std::is_same<T, qint16_t>::value, void>::type activation(const Window &window);
 
 private:
     ITensor                      *_input;
diff --git a/arm_compute/runtime/NEON/functions/NEActivationLayer.h b/arm_compute/runtime/NEON/functions/NEActivationLayer.h
index b1a211553d..f3cd305910 100644
--- a/arm_compute/runtime/NEON/functions/NEActivationLayer.h
+++ b/arm_compute/runtime/NEON/functions/NEActivationLayer.h
@@ -44,7 +44,7 @@ public:
      * @note If the output tensor is a nullptr, the activation function will be performed in-place
      *
      * @param[in, out] input           Source tensor. In case of @p output tensor = nullptr, this tensor will store the result
-     *                                 of the activation function. Data types supported: QS8/F32.
+     *                                 of the activation function. Data types supported: QS8/QS16/F32.
      * @param[out]     output          Destination tensor. Data type supported: same as @p input
      * @param[in]      activation_info Activation layer parameters.
      */