1 // Auto-generated file. Do not edit! 2 // Template: src/f32-sigmoid/scalar-lut64-p2-div.c.in 3 // Generator: tools/xngen 4 // 5 // Copyright 2019 Google LLC 6 // 7 // This source code is licensed under the BSD-style license found in the 8 // LICENSE file in the root directory of this source tree. 9 10 #include <assert.h> 11 #include <math.h> 12 13 #include <xnnpack/common.h> 14 #include <xnnpack/vunary.h> 15 16 #include <fp16/bitcasts.h> 17 18 19 // Note redefine as uint32[] to avoid redundant bitcasts. 20 extern XNN_INTERNAL const uint32_t xnn_table_exp2minus_k_over_64[64]; 21 xnn_f32_sigmoid_ukernel__scalar_lut64_p2_div_x2(size_t n,const float * x,float * y,const void * params)22void xnn_f32_sigmoid_ukernel__scalar_lut64_p2_div_x2( 23 size_t n, 24 const float* x, 25 float* y, 26 const void* params) 27 { 28 assert(n % sizeof(float) == 0); 29 30 const float vmagic_bias = 0x1.800000p17f; 31 const float vminus_log2e = -0x1.715476p0f; 32 const uint32_t vindex_mask = UINT32_C(0x3F); 33 const float vln2_hi = 0x1.630000p-1f; 34 const float vln2_lo = -0x1.BD0106p-13f; 35 const float vc2 = 0x1.FFFF0Ap-2f; 36 const float vone = 1.0f; 37 const float vdenorm_cutoff = 0x1.5D589Ep+6f; 38 39 for (; n >= 2 * sizeof(float); n -= 2 * sizeof(float)) { 40 const float vx0 = x[0]; 41 const float vx1 = x[1]; 42 x += 2; 43 44 const float vz0 = fabsf(vx0); 45 const float vz1 = fabsf(vx1); 46 47 float vn0 = vz0 * vminus_log2e + vmagic_bias; 48 float vn1 = vz1 * vminus_log2e + vmagic_bias; 49 50 const uint32_t ve0 = fp32_to_bits(vn0) << 17; 51 const uint32_t ve1 = fp32_to_bits(vn1) << 17; 52 53 const uint32_t vidx0 = fp32_to_bits(vn0) & vindex_mask; 54 const float vs0 = fp32_from_bits(xnn_table_exp2minus_k_over_64[vidx0] + ve0); 55 const uint32_t vidx1 = fp32_to_bits(vn1) & vindex_mask; 56 const float vs1 = fp32_from_bits(xnn_table_exp2minus_k_over_64[vidx1] + ve1); 57 58 vn0 -= vmagic_bias; 59 vn1 -= vmagic_bias; 60 61 float vt0 = vn0 * vln2_hi + vz0; 62 float vt1 = vn1 * vln2_hi + vz1; 63 64 vt0 = vn0 * vln2_lo + vt0; 65 vt1 = vn1 * vln2_lo + vt1; 66 67 float vp0 = vt0 * vc2; 68 float vp1 = vt1 * vc2; 69 70 vp0 = vt0 - vp0 * vt0; 71 vp1 = vt1 - vp1 * vt1; 72 73 const float vy0 = vs0 - vs0 * vp0; 74 const float vy1 = vs1 - vs1 * vp1; 75 76 const float vd0 = vy0 + vone; 77 const float vd1 = vy1 + vone; 78 79 float vf0 = vy0 / vd0; 80 float vf1 = vy1 / vd1; 81 82 if XNN_UNPREDICTABLE(vz0 > vdenorm_cutoff) { 83 vf0 = 0.0f; 84 } 85 if XNN_UNPREDICTABLE(vz1 > vdenorm_cutoff) { 86 vf1 = 0.0f; 87 } 88 89 if XNN_UNPREDICTABLE(vx0 > 0.0f) { 90 vf0 = vone - vf0; 91 } 92 if XNN_UNPREDICTABLE(vx1 > 0.0f) { 93 vf1 = vone - vf1; 94 } 95 96 y[0] = vf0; 97 y[1] = vf1; 98 y += 2; 99 } 100 if XNN_UNLIKELY(n != 0) { 101 const float vx = *x; 102 103 const float vz = fabsf(vx); 104 105 float vn = vz * vminus_log2e + vmagic_bias; 106 const uint32_t ve = fp32_to_bits(vn) << 17; 107 const uint32_t vidx = fp32_to_bits(vn) & vindex_mask; 108 const float vs = fp32_from_bits(xnn_table_exp2minus_k_over_64[vidx] + ve); 109 vn -= vmagic_bias; 110 111 float vt = vn * vln2_hi + vz; 112 vt = vn * vln2_lo + vt; 113 114 float vp = vt * vc2; 115 vp = vt - vp * vt; 116 117 const float vy = vs - vs * vp; 118 const float vd = vy + vone; 119 120 float vf = vy / vd; 121 if XNN_UNPREDICTABLE(vz > vdenorm_cutoff) { 122 vf = 0.0f; 123 } 124 if XNN_UNPREDICTABLE(vx > 0.0f) { 125 vf = vone - vf; 126 } 127 128 *y = vf; 129 } 130 } 131