Break up loop for numeric stability

This commit is contained in:
Matvey Soloviev 2023-03-23 03:14:44 +01:00
parent 69071d3b6b
commit 711224708d

16
ggml.c
View File

@ -1700,12 +1700,19 @@ inline static void ggml_vec_dot_q4_1(const int n, float * restrict s, const void
#if defined(__AVX2__)
#if QK == 32
// Initialize accumulator with zeros
__m256 acc = _mm256_setzero_ps();
__m256 acc;
// Accumulator for constant offsets
__m128 acc_offset = _mm_setzero_ps(); //0.0f;
__m128 acc_offset;
int i = 0;
#define LOOP_SPLITS 2
#pragma GCC unroll 999
for(int j = 1; j <= LOOP_SPLITS; ++j) {
acc = _mm256_setzero_ps();
acc_offset = _mm_setzero_ps();
// Main loop
for (int i = 0; i < nb; ++i) {
for (; i < (j*nb)/LOOP_SPLITS; ++i) {
const float * m0 = (const float *) (pm0 + i*bs);
const float * m1 = (const float *) (pm1 + i*bs);
@ -1775,7 +1782,8 @@ inline static void ggml_vec_dot_q4_1(const int n, float * restrict s, const void
res = _mm_add_ps( res, _mm_movehl_ps( res, res ) );
res = _mm_add_ss( res, _mm_movehdup_ps( res ) );
sumf = _mm_cvtss_f32( res ) + _mm_cvtss_f32( acc_offset )* QK;
sumf += _mm_cvtss_f32( res ) + _mm_cvtss_f32( acc_offset )* QK;
}
#else
#error "not implemented for QK"
#endif