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Author: Srihari-mcw

ggml/src/ggml-quants.c

@@ -4481,6 +4481,7 @@ void ggml_vec_dot_q4_0_b16_q8_0_b16(int n, float * restrict s, size_t bs, const
         __m128bh xd = m128bh(_mm_cvtepu16_epi32(_mm_set_epi64x(0, x_delta)));
         __m128bh yd = m128bh(_mm_cvtepu16_epi32(_mm_set_epi64x(0, y_delta)));
 
+        // Computes product of delta values from four corresponding blocks
         __m256 d =  _mm256_castps128_ps256(_mm_dpbf16_ps(zerovec, xd, yd));
         d = _mm256_permute2f128_ps(d ,d, 0);
 
@@ -6040,6 +6041,7 @@ void ggml_vec_dot_q8_0_b16_q8_0_b16(int n, float * restrict s, size_t bs, const
         __m128bh xd = m128bh(_mm_cvtepu16_epi32(_mm_set_epi64x(0, x_delta)));
         __m128bh yd = m128bh(_mm_cvtepu16_epi32(_mm_set_epi64x(0, y_delta)));
 
+        // Computes product of delta values from four corresponding blocks
         __m256 d =  _mm256_castps128_ps256(_mm_dpbf16_ps(zerovec, xd, yd));
         d = _mm256_permute2f128_ps(d ,d, 0);
 

ggml/src/llamafile/sgemm.cpp

@@ -981,6 +981,7 @@ class tinyBLAS_Q0_B16_AVX {
     }
 
 #if defined(__AVX512BF16__)
+// Templated functions for gemm of dimesnions 4xN
     template <int RN>
     NOINLINE void gemm4xN(int64_t m0, int64_t m, int64_t n0, int64_t n) {
         int64_t ytiles = (m - m0) / 4;
@@ -1005,6 +1006,7 @@ class tinyBLAS_Q0_B16_AVX {
                 __m256i avec3 = load(A + lda * (ii + 3) + l);
                 for (int64_t j = 0; j < RN; ++j) {
                         __m128bh db = m128bh(_mm_set1_epi16(B[ldb * (jj + j) + l].d));
+                        // Computation of product of delta values for four blocks
                         __m256 dvec =  _mm256_castps128_ps256(_mm_dpbf16_ps(zerovec, da, db));
                         dvec = _mm256_permute2f128_ps(dvec ,dvec, 0);
                         Cv[j][0] = madd(_mm256_shuffle_ps(dvec, dvec, 0),
@@ -1056,7 +1058,8 @@ class tinyBLAS_Q0_B16_AVX {
                 __m256i bvec3 = load(B + ldb * (jj + 3) + l);
                 for (int64_t i = 0; i < RM; ++i) {
                     __m128bh da = m128bh(_mm_set1_epi16((A[lda * (ii + i) + l].d)));
-                   __m256 dvec =  _mm256_castps128_ps256(_mm_dpbf16_ps(zerovec, da, db));
+                    // Computation of product of delta values for four blocks
+                    __m256 dvec =  _mm256_castps128_ps256(_mm_dpbf16_ps(zerovec, da, db));
                     dvec = _mm256_permute2f128_ps(dvec ,dvec, 0);
                     Cv[0][i] = madd(_mm256_shuffle_ps(dvec, dvec, 0),
                                     updot(_mm256_sign_epi8(load(A + lda * (ii + i) + l),