COMPMID-406: Port CLActivationLayer to use QS8/QS16.

Change-Id: Ia4114984c38e1d2027ad97335b3c6c11f5754e23
Reviewed-on: http://mpd-gerrit.cambridge.arm.com/78727
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
Tested-by: Kaizen <jeremy.johnson+kaizengerrit@arm.com>

3 files changed, 208 insertions, 72 deletions

diff --git a/src/core/CL/cl_kernels/activation_layer.cl b/src/core/CL/cl_kernels/activation_layer.cl
index 721c43c017..5f812cf5b3 100644
--- a/src/core/CL/cl_kernels/activation_layer.cl
+++ b/src/core/CL/cl_kernels/activation_layer.cl
@@ -23,16 +23,99 @@
  */
 #include "helpers.h"
 
+#define TYPE VEC_DATA_TYPE(DATA_TYPE, VEC_SIZE)
+
+#if defined(FIXED_POINT_POSITION)
+#include "fixed_point.h"
+
+#define CONST_ONE (1 << FIXED_POINT_POSITION)
+#define ABS_OP(a) ABS_SAT_OP_EXPAND((a), DATA_TYPE, VEC_SIZE)
+#define ADD_OP(a, b) ADD_SAT_OP_EXPAND((a), (b), DATA_TYPE, VEC_SIZE)
+#define SUB_OP(a, b) SUB_SAT_OP_EXPAND((a), (b), DATA_TYPE, VEC_SIZE)
+#define MUL_OP(a, b) MUL_SAT_OP_EXPAND((a), (b), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION)
+#define MLA_OP(a, b, c) MLA_SAT_OP_EXPAND((a), (b), (c), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION)
+#define DIV_OP(a, b) DIV_SAT_OP_EXPAND((a), (b), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION)
+#define EXP_OP(a) EXP_OP_EXPAND((a), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION)
+#define LOG_OP(a) LOG_OP_EXPAND((a), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION)
+#define SQRT_OP(a) DIV_OP(CONST_ONE, INVSQRT_OP_EXPAND((a), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION))
+#define TANH_OP(a) TANH_OP_EXPAND((a), DATA_TYPE, VEC_SIZE, FIXED_POINT_POSITION)
+
+#else /* FIXED_POINT_POSITION */
+
+#define CONST_ONE (1.f)
+#define ABS_OP(a) fabs((a))
+#define ADD_OP(a, b) ((a) + (b))
+#define SUB_OP(a, b) ((a) - (b))
+#define MUL_OP(a, b) ((a) * (b))
+#define MLA_OP(a, b, c) ((b) * (c) + (a))
+#define DIV_OP(a, b) ((a) / (b))
+#define EXP_OP(a) exp((a))
+#define LOG_OP(a) log((a))
+#define SQRT_OP(a) sqrt((a))
+#define TANH_OP(a) tanh((a))
+
+#endif /* FIXED_POINT_POSITION */
+
+// Logistic Activation
+inline TYPE logistic_op(TYPE x)
+{
+    return DIV_OP(CONST_ONE, ADD_OP(CONST_ONE, EXP_OP(-x)));
+}
+// Hyperbolic Tangent Activation
+inline TYPE tanh_op(TYPE x)
+{
+    return MUL_OP((TYPE)A_VAL, TANH_OP(MUL_OP((TYPE)B_VAL, x)));
+}
+// RELU Tangent Activation
+inline TYPE relu_op(TYPE x)
+{
+    return max(0, x);
+}
+// Bounded RELU Activation
+inline TYPE brelu_op(TYPE x)
+{
+    return min((TYPE)A_VAL, max(0, x));
+}
+// Soft RELU Activation
+inline TYPE srelu_op(TYPE x)
+{
+    return LOG_OP(ADD_OP(CONST_ONE, EXP_OP(x)));
+}
+// Absolute Activation
+inline TYPE abs_op(TYPE x)
+{
+    return ABS_OP(x);
+}
+// Square Activation
+inline TYPE square_op(TYPE x)
+{
+    return MUL_OP(x, x);
+}
+// Square-root Activation
+inline TYPE sqrt_op(TYPE x)
+{
+    return SQRT_OP(x);
+}
+// Linear Activation
+inline TYPE linear_op(TYPE x)
+{
+    return MLA_OP((TYPE)B_VAL, (TYPE)A_VAL, x);
+}
+
+#define ACTIVATION_OP2(op, x) op##_op(x)
+#define ACTIVATION_OP(op, x) ACTIVATION_OP2(op, x)
+
 /** This performs an activation function floating point inputs.
  *
  * @note In order to perform the activation function "in-place", the pre-processor -DIN_PLACE must be passed at compile time
  *
  * @note Datatype should be given as a preprocessor argument using -DDATA_TYPE=type. e.g. -DDATA_TYPE=short
- * @note Activation function should be given as a preprocessor argument using -DNAME. e.g. -DTANH
- * @note Distinction between floating point and integer is done using -DTYPE_FP and -DTYPE_INT preprocessor argument
- * @note A, B variables required by some activation functions are set using -DA= and -DB= respectively.
+ * @note Vector size should be given as a preprocessor argument using -DVEC_SIZE=size. e.g. -DVEC_SIZE=16
+ * @note Activation function should be given as a preprocessor argument using -DACT=name. e.g. -DACT=TANH
+ * @note A, B variables required by some activation functions are set using -DA_VAL= and -DB_VAL= respectively.
+ * @note In case of fixed point calculations the fixed point position is passed using -DFIXED_POINT_POSITION=position. e.g. -DFIXED_POINT_POSITION=3.
  *
- * @param[in]  input_ptr                            Pointer to the source image. Supported data types: F16, F32
+ * @param[in]  input_ptr                            Pointer to the source image. Supported data types: QS8/QS16/F16/F32
  * @param[in]  input_stride_x                       Stride of the source image in X dimension (in bytes)
  * @param[in]  input_step_x                         input_stride_x * number of elements along X processed per workitem(in bytes)
  * @param[in]  input_stride_y                       Stride of the source image in Y dimension (in bytes)
@@ -40,7 +123,7 @@
  * @param[in]  input_stride_z                       Stride of the source tensor in Z dimension (in bytes)
  * @param[in]  input_step_z                         input_stride_z * number of elements along Z processed per workitem(in bytes)
  * @param[in]  input_offset_first_element_in_bytes  The offset of the first element in the source image
- * @param[out] output_ptr                           Pointer to the destination image. Supported data types: F16, F32
+ * @param[out] output_ptr                           Pointer to the destination image. Supported data types: same as @p input_ptr
  * @param[in]  output_stride_x                      Stride of the destination image in X dimension (in bytes)
  * @param[in]  output_step_x                        output_stride_x * number of elements along X processed per workitem(in bytes)
  * @param[in]  output_stride_y                      Stride of the destination image in Y dimension (in bytes)
@@ -66,34 +149,12 @@ __kernel void activation_layer(
 #endif /* IN_PLACE */
 
     // Load data
-    VEC_DATA_TYPE(DATA_TYPE, 16)
-    data = vload16(0, (__global DATA_TYPE *)input.ptr);
+    TYPE data = VLOAD(VEC_SIZE)(0, (__global DATA_TYPE *)input.ptr);
 
     // Perform activation
-#ifdef LOGISTIC
-    data = 1 / (1 + exp(-data));
-#elif defined(TANH)
-    data            = (VEC_DATA_TYPE(DATA_TYPE, 16))A * tanh((VEC_DATA_TYPE(DATA_TYPE, 16))B * data);
-#elif defined(RELU)
-    data = max(0, data);
-#elif defined(BRELU)
-    data = min((VEC_DATA_TYPE(DATA_TYPE, 16))A, max(0, data));
-#elif defined(SRELU)
-    data = log(1 + exp(data));
-#elif defined(ABS)
-#ifdef TYPE_INT
-    data = abs(data);
-#else  /* TYPE_INT */
-    data = fabs(data);
-#endif /* TYPE_INT */
-#elif defined(SQUARE)
-    data = data * data;
-#elif defined(SQRT)
-    data = sqrt(data);
-#elif defined(LINEAR)
-    data = (VEC_DATA_TYPE(DATA_TYPE, 16))A * data + (VEC_DATA_TYPE(DATA_TYPE, 16))B;
-#endif /* switch TANH, RELU, BRELU, SRELU, ABS, SQUARE, SQRT, LINEAR */
+    data = ACTIVATION_OP(ACT, data);
 
     // Store result
-    vstore16(data, 0, (__global DATA_TYPE *)output.ptr);
+    VSTORE(VEC_SIZE)
+    (data, 0, (__global DATA_TYPE *)output.ptr);
 }
diff --git a/src/core/CL/cl_kernels/fixed_point.h b/src/core/CL/cl_kernels/fixed_point.h
index 5d340c4e95..bb534f5a51 100644
--- a/src/core/CL/cl_kernels/fixed_point.h
+++ b/src/core/CL/cl_kernels/fixed_point.h
@@ -99,6 +99,24 @@ TYPE_ALIAS(int, qs32)
 #define CONVERT_SAT_STR(x, type) CONVERT_SAT_STR2(x, type, type##_TYPE)
 #define CONVERT_SAT(x, type) CONVERT_SAT_STR(x, type)
 
+/** Computes saturating absolute value of fixed point vector.
+  *
+  * @param[in] type the actual data type.
+  *
+  * @return The result of the fixed point absolute value.
+  */
+#define ABSQ_SAT_IMPL(type)                  \
+    inline type abs_##type##_sat(type VopA)  \
+    {                                        \
+        return CONVERT_SAT(abs(VopA), type); \
+    }
+
+ABSQ_SAT_IMPL(qs8x16)
+ABSQ_SAT_IMPL(qs16x8)
+
+#define ABS_SAT_OP_EXPAND_STR(a, type, size) abs_##type##x##size##_sat((a))
+#define ABS_SAT_OP_EXPAND(a, type, size) ABS_SAT_OP_EXPAND_STR(a, type, size)
+
 /** Computes max of fixed point types.
   *
   * @param[in] type the actual data type.
@@ -280,6 +298,7 @@ MLALQ_SAT_IMPL(qs16x8, qs32x8)
     }
 
 DIVQ_SAT_IMPL(qs8, qs8x16, qs16x16)
+DIVQ_SAT_IMPL(qs16, qs16x8, qs32x8)
 DIVQ_SAT_IMPL(qs16, qs16x16, qs32x16)
 
 #define DIV_SAT_OP_EXPAND_STR(a, b, type, size, position) div_sat_##type##x##size((a), (b), (position))
@@ -287,34 +306,37 @@ DIVQ_SAT_IMPL(qs16, qs16x16, qs32x16)
 
 /** Saturate exponential of a fixed point vector
   *
+  * @note Implemented approach uses taylor polynomial to approximate the exponential function.
+  *
   * @param[in] stype the actual scalar data type.
   * @param[in] type  the actual data type.
   * @param[in] size  the number of the calculated elements.
   *
   * @return The result of the fixed point exponential. The result is saturated in case of overflow
   */
-#define EXPQ_IMPL(stype, type, size)                                                                                     \
-    inline type exp_sat_##type(type VopA, int fixed_point_position)                                                      \
-    {                                                                                                                    \
-        type const_one = (type)(1 << (fixed_point_position));                                                            \
-        type ln2       = (type)((((0x58B9 >> (14 - fixed_point_position))) + 1) >> 1);                                   \
-        type inv_ln2   = (type)((((0x38AA >> (14 - fixed_point_position)) + 1) >> 1)) | const_one;                       \
-        type A         = (type)(((0x7FBA >> (14 - fixed_point_position)) + 1) >> 1);                                     \
-        type B         = (type)(((0x3FE9 >> (14 - fixed_point_position)) + 1) >> 1);                                     \
-        type C         = (type)(((0x1693 >> (14 - fixed_point_position)) + 1) >> 1);                                     \
-        type D         = (type)(((0x0592 >> (14 - fixed_point_position)) + 1) >> 1);                                     \
-        type m         = MUL_SAT_OP_EXPAND(VopA, inv_ln2, stype, size, fixed_point_position);                            \
-        type dec_m     = m >> (type)fixed_point_position;                                                                \
-        type alpha     = MUL_SAT_OP_EXPAND(dec_m << (type)fixed_point_position, ln2, stype, size, fixed_point_position); \
-        alpha          = CONVERT(abs_diff(VopA, alpha), type);                                                           \
-        type sum       = add_sat(MUL_SAT_OP_EXPAND(alpha, D, stype, size, fixed_point_position), C);                     \
-        sum            = add_sat(MUL_SAT_OP_EXPAND(alpha, sum, stype, size, fixed_point_position), B);                   \
-        sum            = add_sat(MUL_SAT_OP_EXPAND(alpha, sum, stype, size, fixed_point_position), A);                   \
-        sum            = add_sat(MUL_SAT_OP_EXPAND(alpha, sum, stype, size, fixed_point_position), const_one);           \
-        return select(select(sum << dec_m, sum >> -dec_m, dec_m < (type)0), (type)stype##_MAX, clz(sum) <= dec_m);       \
+#define EXPQ_IMPL(stype, type, size)                                                                                                              \
+    inline type exp_sat_##type(type VopA, int fixed_point_position)                                                                               \
+    {                                                                                                                                             \
+        type const_one = (type)(1 << (fixed_point_position));                                                                                     \
+        type ln2       = (type)((((0x58B9 >> (14 - fixed_point_position))) + 1) >> 1);                                                            \
+        type inv_ln2   = (type)((((0x38AA >> (14 - fixed_point_position)) + 1) >> 1)) | const_one;                                                \
+        type A         = (type)(((0x7FBA >> (14 - fixed_point_position)) + 1) >> 1);                                                              \
+        type B         = (type)(((0x3FE9 >> (14 - fixed_point_position)) + 1) >> 1);                                                              \
+        type C         = (type)(((0x1693 >> (14 - fixed_point_position)) + 1) >> 1);                                                              \
+        type D         = (type)(((0x0592 >> (14 - fixed_point_position)) + 1) >> 1);                                                              \
+        type m         = MUL_SAT_OP_EXPAND(VopA, inv_ln2, stype, size, fixed_point_position);                                                     \
+        type dec_m     = m >> (type)fixed_point_position;                                                                                         \
+        type alpha     = MUL_SAT_OP_EXPAND(dec_m << (type)fixed_point_position, ln2, stype, size, fixed_point_position);                          \
+        alpha          = CONVERT(abs_diff(VopA, alpha), type);                                                                                    \
+        type sum       = add_sat(MUL_SAT_OP_EXPAND(alpha, D, stype, size, fixed_point_position), C);                                              \
+        sum            = add_sat(MUL_SAT_OP_EXPAND(alpha, sum, stype, size, fixed_point_position), B);                                            \
+        sum            = add_sat(MUL_SAT_OP_EXPAND(alpha, sum, stype, size, fixed_point_position), A);                                            \
+        sum            = add_sat(MUL_SAT_OP_EXPAND(alpha, sum, stype, size, fixed_point_position), const_one);                                    \
+        return select((type)stype##_MAX, select(sum << dec_m, sum >> -dec_m, dec_m < (type)0), clz(sum) > dec_m); /* Saturate result if needed */ \
     }
 
 EXPQ_IMPL(qs8, qs8x16, 16)
+EXPQ_IMPL(qs16, qs16x8, 8)
 EXPQ_IMPL(qs16, qs16x16, 16)
 
 #define EXP_OP_EXPAND_STR(a, type, size, position) exp_sat_##type##x##size((a), (position))
@@ -322,6 +344,8 @@ EXPQ_IMPL(qs16, qs16x16, 16)
 
 /** Saturate logarithm of a fixed point vector
   *
+  * @note Implemented approach uses taylor polynomial to approximate the logarithm function.
+  *
   * @param[in] stype the actual scalar data type.
   * @param[in] type  the actual data type.
   * @param[in] size  the number of the calculated elements.
@@ -332,11 +356,11 @@ EXPQ_IMPL(qs16, qs16x16, 16)
     inline type log_sat_##type(type VopA, int fixed_point_position)                                                                        \
     {                                                                                                                                      \
         type const_one = (type)(1 << (fixed_point_position));                                                                              \
-        type ln2       = (type)(0x58B9 >> (15 - fixed_point_position));                                                                    \
-        type A         = (type)(0x5C0F >> (14 - fixed_point_position));                                                                    \
-        type B         = -(type)(0x56AE >> (15 - fixed_point_position));                                                                   \
-        type C         = (type)(0x2933 >> (15 - fixed_point_position));                                                                    \
-        type D         = -(type)(0x0AA7 >> (15 - fixed_point_position));                                                                   \
+        type ln2       = (type)(0x58B9 >> (15 - fixed_point_position));  /* 1.4384189 */                                                   \
+        type A         = (type)(0x5C0F >> (14 - fixed_point_position));  /* 1.4384189 */                                                   \
+        type B         = -(type)(0x56AE >> (15 - fixed_point_position)); /* -0.6771900 */                                                  \
+        type C         = (type)(0x2933 >> (15 - fixed_point_position));  /* 0.3218538 */                                                   \
+        type D         = -(type)(0x0AA7 >> (15 - fixed_point_position)); /* -0.0832229 */                                                  \
         type inter_a   = select(VopA, DIV_SAT_OP_EXPAND(const_one, VopA, stype, size, fixed_point_position), VopA < const_one);            \
         type shift_val = (type)(15 - stype##_SHIFT) - clz(inter_a >> (type)fixed_point_position);                                          \
         inter_a        = inter_a >> shift_val;                                                                                             \
@@ -346,16 +370,19 @@ EXPQ_IMPL(qs16, qs16x16, 16)
         sum            = add_sat(MUL_SAT_OP_EXPAND(inter_a, sum, stype, size, fixed_point_position), A);                                   \
         sum            = MUL_SAT_OP_EXPAND(inter_a, sum, stype, size, fixed_point_position);                                               \
         sum            = MUL_SAT_OP_EXPAND(add_sat(sum, shift_val << (type)fixed_point_position), ln2, stype, size, fixed_point_position); \
-        return select(select(sum, -sum, VopA < const_one), (type)0, VopA < (type)0);                                                       \
+        return select(select(sum, -sum, VopA < const_one), (type)0, VopA < (type)0); /* Saturate result if needed */                       \
     }
 
 LOGQ_IMPL(qs8, qs8x16, 16)
+LOGQ_IMPL(qs16, qs16x8, 8)
 
 #define LOG_OP_EXPAND_STR(a, type, size, position) log_sat_##type##x##size((a), (position))
 #define LOG_OP_EXPAND(a, type, size, position) LOG_OP_EXPAND_STR(a, type, size, position)
 
 /** Saturate inverse square root of a fixed point vector
   *
+  * @note Implemented approach uses Newton's method to approximate the inverse square root function.
+  *
   * @param[in] stype the actual scalar data type.
   * @param[in] type  the actual data type.
   * @param[in] size  the number of the calculated elements.
@@ -367,20 +394,53 @@ LOGQ_IMPL(qs8, qs8x16, 16)
     {                                                                                                                                                                                                                                  \
         type const_three = (type)(3 << (fixed_point_position));                                                                                                                                                                        \
         type shift_value = (type)(16 - stype##_SHIFT) - (clz(VopA) + (type)fixed_point_position);                                                                                                                                      \
-        type temp        = select(VopA >> shift_value, VopA << (-shift_value), shift_value < (type)0);                                                                                                                                 \
+        type temp        = select(VopA >> shift_value, select((type)stype##_MAX, VopA << (-shift_value), clz(VopA) > (-shift_value)), shift_value < (type)0);                                                                          \
         type x           = temp;                                                                                                                                                                                                       \
         x                = MUL_SAT_OP_EXPAND(x, sub_sat(const_three, MUL_SAT_OP_EXPAND(MUL_SAT_OP_EXPAND(x, x, stype, size, fixed_point_position), temp, stype, size, fixed_point_position)), stype, size, fixed_point_position) >> 1; \
         x                = MUL_SAT_OP_EXPAND(x, sub_sat(const_three, MUL_SAT_OP_EXPAND(MUL_SAT_OP_EXPAND(x, x, stype, size, fixed_point_position), temp, stype, size, fixed_point_position)), stype, size, fixed_point_position) >> 1; \
         x                = MUL_SAT_OP_EXPAND(x, sub_sat(const_three, MUL_SAT_OP_EXPAND(MUL_SAT_OP_EXPAND(x, x, stype, size, fixed_point_position), temp, stype, size, fixed_point_position)), stype, size, fixed_point_position) >> 1; \
-        type res         = select(x >> (shift_value >> 1), x << ((-shift_value) >> 1), shift_value < (type)0);                                                                                                                         \
-        return select(res, stype##_MAX, res < (type)0);                                                                                                                                                                                \
+        if(sizeof((stype)(1)) > 1) /* Perform more iterations if datatype is QS16 */                                                                                                                                                   \
+        {                                                                                                                                                                                                                              \
+            x = MUL_SAT_OP_EXPAND(x, sub_sat(const_three, MUL_SAT_OP_EXPAND(MUL_SAT_OP_EXPAND(x, x, stype, size, fixed_point_position), temp, stype, size, fixed_point_position)), stype, size, fixed_point_position) >> 1;            \
+            x = MUL_SAT_OP_EXPAND(x, sub_sat(const_three, MUL_SAT_OP_EXPAND(MUL_SAT_OP_EXPAND(x, x, stype, size, fixed_point_position), temp, stype, size, fixed_point_position)), stype, size, fixed_point_position) >> 1;            \
+        }                                                                                                                                                                                                                              \
+        type shift_value2 = select(shift_value >> 1, (-shift_value) >> 1, shift_value < (type)0);                                                                                                                                      \
+        return select(x >> shift_value2, select((type)stype##_MAX, x << shift_value2, clz(x) > shift_value2), shift_value < (type)0); /* Saturate result if needed */                                                                  \
     }
 
 INVSQRTQ_IMPL(qs8, qs8x16, 16)
+INVSQRTQ_IMPL(qs16, qs16x8, 8)
 
 #define INVSQRT_OP_EXPAND_STR(a, type, size, position) invsqrt_sat_##type##x##size((a), (position))
 #define INVSQRT_OP_EXPAND(a, type, size, position) INVSQRT_OP_EXPAND_STR(a, type, size, position)
 
+/** Saturate hyperbolic tangent of a fixed point vector
+  *
+  * tanh(x) = (e^2x - 1)/(e^2x + 1)
+  *
+  * @param[in] stype the actual scalar data type.
+  * @param[in] type  the actual data type.
+  * @param[in] size  the number of the calculated elements.
+  *
+  * @return The result of the fixed point hyperbolic tangent. The result is saturated in case of overflow
+  */
+#define TANHQ_IMPL(stype, type, size)                                                                                                             \
+    inline type tanh_sat_##type(type VopA, int fixed_point_position)                                                                              \
+    {                                                                                                                                             \
+        type const_one = (type)(1 << (fixed_point_position));                                                                                     \
+        type const_two = (type)(2 << (fixed_point_position));                                                                                     \
+        type exp2x     = EXP_OP_EXPAND(MUL_SAT_OP_EXPAND(const_two, VopA, stype, size, fixed_point_position), stype, size, fixed_point_position); \
+        type num       = SUB_SAT_OP_EXPAND(exp2x, const_one, stype, size);                                                                        \
+        type den       = ADD_SAT_OP_EXPAND(exp2x, const_one, stype, size);                                                                        \
+        return DIV_SAT_OP_EXPAND(num, den, stype, size, fixed_point_position);                                                                    \
+    }
+
+TANHQ_IMPL(qs8, qs8x16, 16)
+TANHQ_IMPL(qs16, qs16x8, 8)
+
+#define TANH_OP_EXPAND_STR(a, type, size, position) tanh_sat_##type##x##size((a), (position))
+#define TANH_OP_EXPAND(a, type, size, position) TANH_OP_EXPAND_STR(a, type, size, position)
+
 #define floatx16 float16
 #define float16_TYPE float16
 
diff --git a/src/core/CL/kernels/CLActivationLayerKernel.cpp b/src/core/CL/kernels/CLActivationLayerKernel.cpp
index fda69b0b94..18202c1c5b 100644
--- a/src/core/CL/kernels/CLActivationLayerKernel.cpp
+++ b/src/core/CL/kernels/CLActivationLayerKernel.cpp
@@ -26,6 +26,7 @@
 #include "arm_compute/core/CL/CLHelpers.h"
 #include "arm_compute/core/CL/CLKernelLibrary.h"
 #include "arm_compute/core/CL/ICLTensor.h"
+#include "arm_compute/core/FixedPoint.h"
 #include "arm_compute/core/Helpers.h"
 #include "arm_compute/core/IAccessWindow.h"
 #include "arm_compute/core/TensorInfo.h"
@@ -33,6 +34,10 @@
 #include "arm_compute/core/Validate.h"
 #include "arm_compute/core/Window.h"
 
+#include "support/ToolchainSupport.h"
+
+#include <cmath>
+
 using namespace arm_compute;
 
 CLActivationLayerKernel::CLActivationLayerKernel()
@@ -42,7 +47,7 @@ CLActivationLayerKernel::CLActivationLayerKernel()
 
 void CLActivationLayerKernel::configure(ICLTensor *input, ICLTensor *output, ActivationLayerInfo act_info)
 {
-    ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(input, 1, DataType::F16, DataType::F32);
+    ARM_COMPUTE_ERROR_ON_DATA_TYPE_CHANNEL_NOT_IN(input, 1, DataType::QS8, DataType::QS16, DataType::F16, DataType::F32);
 
     if(output != nullptr)
     {
@@ -54,20 +59,33 @@ void CLActivationLayerKernel::configure(ICLTensor *input, ICLTensor *output, Act
         ARM_COMPUTE_ERROR_ON_MISMATCHING_FIXED_POINT(input, output);
     }
 
+    const unsigned int num_elems_processed_per_iteration = 16 / input->info()->element_size();
+    const int          fixed_point_position              = input->info()->fixed_point_position();
+    float              a_const                           = act_info.a();
+    float              b_const                           = act_info.b();
+    if(is_data_type_fixed_point(input->info()->data_type()))
+    {
+        a_const = static_cast<int>(lround(a_const * (1 << fixed_point_position)));
+        b_const = static_cast<int>(lround(b_const * (1 << fixed_point_position)));
+    }
+
     // Set build options
     std::set<std::string> build_opts;
-    build_opts.insert(("-D" + string_from_activation_func(act_info.activation())));
-    build_opts.insert(("-D" + ((is_data_type_float(input->info()->data_type())) ? std::string("TYPE_FP") : std::string("TYPE_INT"))));
-    build_opts.insert(("-DDATA_TYPE=" + get_cl_type_from_data_type(input->info()->data_type())));
-    build_opts.insert(("-DA=" + support::cpp11::to_string(act_info.a())));
-    build_opts.insert(("-DB=" + support::cpp11::to_string(act_info.b())));
-    build_opts.insert(output == nullptr ? "-DIN_PLACE" : "");
+    build_opts.emplace(("-DACT=" + lower_string(string_from_activation_func(act_info.activation()))));
+    build_opts.emplace(("-DDATA_TYPE=" + get_cl_type_from_data_type(input->info()->data_type())));
+    build_opts.emplace(("-DVEC_SIZE=" + support::cpp11::to_string(num_elems_processed_per_iteration)));
+    build_opts.emplace(("-DA_VAL=" + support::cpp11::to_string(a_const)));
+    build_opts.emplace(("-DB_VAL=" + support::cpp11::to_string(b_const)));
+    build_opts.emplace(output == nullptr ? "-DIN_PLACE" : "");
+    if(is_data_type_fixed_point(input->info()->data_type()))
+    {
+        build_opts.emplace(("-DFIXED_POINT_POSITION=" + support::cpp11::to_string(fixed_point_position)));
+    }
 
     // Create kernel
     _kernel = static_cast<cl::Kernel>(CLKernelLibrary::get().create_kernel("activation_layer", build_opts));
 
     // Make sure _kernel is initialized before calling the parent's configure
-    constexpr unsigned int num_elems_processed_per_iteration = 16;
 
     _input  = input;
     _output = output;
@@ -77,12 +95,9 @@ void CLActivationLayerKernel::configure(ICLTensor *input, ICLTensor *output, Act
 
     if(output != nullptr)
     {
+        AccessWindowHorizontal input_access(input->info(), 0, num_elems_processed_per_iteration);
         AccessWindowHorizontal output_access(output->info(), 0, num_elems_processed_per_iteration);
-
-        update_window_and_padding(win,
-                                  AccessWindowHorizontal(input->info(), 0, num_elems_processed_per_iteration),
-                                  output_access);
-
+        update_window_and_padding(win, input_access, output_access);
         output_access.set_valid_region(win, input->info()->valid_region());
     }
     else