diff --git a/common/includes/simd/avx2_double.h b/common/includes/simd/avx2_double.h
index c48fe6c..e57df9b 100644
--- a/common/includes/simd/avx2_double.h
+++ b/common/includes/simd/avx2_double.h
@@ -48,11 +48,13 @@ static inline MD_FLOAT simd_incr_reduced_sum(MD_FLOAT *m, MD_SIMD_FLOAT v0, MD_S
     t2 = _mm256_permute2f128_pd(t0, t1, 0x21);
     t0 = _mm256_add_pd(t0, t2);
     t1 = _mm256_add_pd(t1, t2);
-    t0 = _mm256_blend_pd(t0, t1, 0b1100);
+    t0 = _mm256_blend_pd(t0, t1, 0xC);
+    //t0 = _mm256_blend_pd(t0, t1, 0b1100);
     t1 = _mm256_add_pd(t0, _mm256_load_pd(m));
     _mm256_store_pd(m, t1);
 
-    t0 = _mm256_add_pd(t0, _mm256_permute_pd(t0, 0b0101));
+    t0 = _mm256_add_pd(t0, _mm256_permute_pd(t0, 0x5));
+    //t0 = _mm256_add_pd(t0, _mm256_permute_pd(t0, 0b0101));
     a0 = _mm256_castpd256_pd128(t0);
     a1 = _mm256_extractf128_pd(t0, 0x1);
     a0 = _mm_add_sd(a0, a1);
@@ -91,7 +93,7 @@ static inline void simd_h_decr3(MD_FLOAT *m, MD_SIMD_FLOAT a0, MD_SIMD_FLOAT a1,
 }
 
 // Functions used in LAMMPS kernel
-static inline MD_SIMD_FLOAT simd_gather(MD_SIMD_INT vidx, const MD_FLOAT *m, int s) { return _mm256_i32gather_pd(m, vidx, s); }
+#define simd_gather(vidx, m, s)     _mm256_i32gather_pd(m, vidx, s);
 static inline MD_SIMD_INT simd_int_broadcast(int scalar) { return _mm_set1_epi32(scalar); }
 static inline MD_SIMD_INT simd_int_zero() { return _mm_setzero_si128(); }
 static inline MD_SIMD_INT simd_int_seq() { return _mm_set_epi32(3, 2, 1, 0); }
diff --git a/gromacs/neighbor.c b/gromacs/neighbor.c
index dfba8f5..ba9fc82 100644
--- a/gromacs/neighbor.c
+++ b/gromacs/neighbor.c
@@ -58,6 +58,7 @@ void initNeighbor(Neighbor *neighbor, Parameter *param) {
     neighbor->numneigh = NULL;
     neighbor->numneigh_masked = NULL;
     neighbor->neighbors = NULL;
+    neighbor->neighbors_imask = NULL;
 }
 
 void setupNeighbor(Parameter *param, Atom *atom) {
@@ -229,7 +230,9 @@ void buildNeighbor(Atom *atom, Neighbor *neighbor) {
     if(atom->Nclusters_local > nmax) {
         nmax = atom->Nclusters_local;
         if(neighbor->numneigh) free(neighbor->numneigh);
+        if(neighbor->numneigh_masked) free(neighbor->numneigh_masked);
         if(neighbor->neighbors) free(neighbor->neighbors);
+        if(neighbor->neighbors_imask) free(neighbor->neighbors_imask);
         neighbor->numneigh = (int*) malloc(nmax * sizeof(int));
         neighbor->numneigh_masked = (int*) malloc(nmax * sizeof(int));
         neighbor->neighbors = (int*) malloc(nmax * neighbor->maxneighs * sizeof(int));
@@ -326,15 +329,17 @@ void buildNeighbor(Atom *atom, Neighbor *neighbor) {
                                     imask = get_imask_simd_4xn(1, ci, cj);
                                     #endif
 
-                                    if(imask == NBNXN_INTERACTION_MASK_ALL) {
-                                        neighptr[n] = cj;
-                                        neighptr_imask[n] = imask;
-                                    } else {
-                                        neighptr[n] = neighptr[nmasked];
-                                        neighptr_imask[n] = neighptr_imask[nmasked];
-                                        neighptr[nmasked] = cj;
-                                        neighptr_imask[nmasked] = imask;
-                                        nmasked++;
+                                    if(n < neighbor->maxneighs) {
+                                        if(imask == NBNXN_INTERACTION_MASK_ALL) {
+                                            neighptr[n] = cj;
+                                            neighptr_imask[n] = imask;
+                                        } else {
+                                            neighptr[n] = neighptr[nmasked];
+                                            neighptr_imask[n] = neighptr_imask[nmasked];
+                                            neighptr[nmasked] = cj;
+                                            neighptr_imask[nmasked] = imask;
+                                            nmasked++;
+                                        }
                                     }
 
                                     n++;
@@ -377,11 +382,12 @@ void buildNeighbor(Atom *atom, Neighbor *neighbor) {
         }
 
         if(resize) {
-            fprintf(stdout, "RESIZE %d\n", neighbor->maxneighs);
             neighbor->maxneighs = new_maxneighs * 1.2;
+            fprintf(stdout, "RESIZE %d\n", neighbor->maxneighs);
             free(neighbor->neighbors);
-            neighbor->neighbors = (int *) malloc(atom->Nmax * neighbor->maxneighs * sizeof(int));
-            neighbor->neighbors_imask = (unsigned int *) malloc(atom->Nmax * neighbor->maxneighs * sizeof(unsigned int));
+            free(neighbor->neighbors_imask);
+            neighbor->neighbors = (int *) malloc(nmax * neighbor->maxneighs * sizeof(int));
+            neighbor->neighbors_imask = (unsigned int *) malloc(nmax * neighbor->maxneighs * sizeof(unsigned int));
         }
     }