diff --git a/src/f32-spmm/1x1-scalar.c b/src/f32-spmm/1x1-scalar.c
index 5d5752f..48029eb 100644
--- a/src/f32-spmm/1x1-scalar.c
+++ b/src/f32-spmm/1x1-scalar.c
@@ -33,23 +33,44 @@
     const int32_t* dmap = widx_dmap;
     const uint32_t* nnzmap = nidx_nnzmap;
     size_t j = n;
-    do {
+    while (j >= 1) {
       uint32_t nnz = *nnzmap++;
-      float vacc0 = *w++;
+      float vacc0x0 = *w++;
       if XNN_LIKELY(nnz != 0) {
         do {
           const intptr_t diff = *dmap++;
           const float va0 = a[0];
           a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-          const float vb = *w++;
-          vacc0 += va0 * vb;
+          const float vb0 = *w++;
+          vacc0x0 += va0 * vb0;
         } while (--nnz != 0);
       }
-      float vout0 = math_min_f32(vacc0, vmax);
-      vout0 = math_max_f32(vout0, vmin);
-      c[0] = vout0;
-      c += m;
-    } while (--j != 0);
+      float vout0x0 = math_min_f32(vacc0x0, vmax);
+      vout0x0 = math_max_f32(vout0x0, vmin);
+      c[0 * m + 0] = vout0x0;
+      c += 1 * m;
+      j -= 1;
+    }
+    if XNN_UNLIKELY(j != 0) {
+      do {
+        uint32_t nnz = *nnzmap++;
+        float vacc0 = *w++;
+        if XNN_LIKELY(nnz != 0) {
+          do {
+            const intptr_t diff = *dmap++;
+            const float va0 = a[0];
+            a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+            const float vb = *w++;
+            vacc0 += va0 * vb;
+          } while (--nnz != 0);
+        }
+        float vout0 = math_min_f32(vacc0, vmax);
+        vout0 = math_max_f32(vout0, vmin);
+        c[0] = vout0;
+        c += m;
+        j -= 1;
+      } while (j != 0);
+    }
     c -= m * n;
     c += 1;
     a += 1;
diff --git a/src/f32-spmm/2x1-scalar.c b/src/f32-spmm/2x1-scalar.c
index 474c2ea..4e33933 100644
--- a/src/f32-spmm/2x1-scalar.c
+++ b/src/f32-spmm/2x1-scalar.c
@@ -33,29 +33,56 @@
     const int32_t* dmap = widx_dmap;
     const uint32_t* nnzmap = nidx_nnzmap;
     size_t j = n;
-    do {
+    while (j >= 1) {
       uint32_t nnz = *nnzmap++;
-      float vacc0 = *w++;
-      float vacc1 = vacc0;
+      float vacc0x0 = *w++;
+      float vacc1x0 = vacc0x0;
       if XNN_LIKELY(nnz != 0) {
         do {
           const intptr_t diff = *dmap++;
           const float va0 = a[0];
           const float va1 = a[1];
           a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-          const float vb = *w++;
-          vacc0 += va0 * vb;
-          vacc1 += va1 * vb;
+          const float vb0 = *w++;
+          vacc0x0 += va0 * vb0;
+          vacc1x0 += va1 * vb0;
         } while (--nnz != 0);
       }
-      float vout0 = math_min_f32(vacc0, vmax);
-      float vout1 = math_min_f32(vacc1, vmax);
-      vout0 = math_max_f32(vout0, vmin);
-      vout1 = math_max_f32(vout1, vmin);
-      c[0] = vout0;
-      c[1] = vout1;
-      c += m;
-    } while (--j != 0);
+      float vout0x0 = math_min_f32(vacc0x0, vmax);
+      float vout1x0 = math_min_f32(vacc1x0, vmax);
+      vout0x0 = math_max_f32(vout0x0, vmin);
+      vout1x0 = math_max_f32(vout1x0, vmin);
+      c[0 * m + 0] = vout0x0;
+      c[0 * m + 1] = vout1x0;
+      c += 1 * m;
+      j -= 1;
+    }
+    if XNN_UNLIKELY(j != 0) {
+      do {
+        uint32_t nnz = *nnzmap++;
+        float vacc0 = *w++;
+        float vacc1 = vacc0;
+        if XNN_LIKELY(nnz != 0) {
+          do {
+            const intptr_t diff = *dmap++;
+            const float va0 = a[0];
+            const float va1 = a[1];
+            a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+            const float vb = *w++;
+            vacc0 += va0 * vb;
+            vacc1 += va1 * vb;
+          } while (--nnz != 0);
+        }
+        float vout0 = math_min_f32(vacc0, vmax);
+        float vout1 = math_min_f32(vacc1, vmax);
+        vout0 = math_max_f32(vout0, vmin);
+        vout1 = math_max_f32(vout1, vmin);
+        c[0] = vout0;
+        c[1] = vout1;
+        c += m;
+        j -= 1;
+      } while (j != 0);
+    }
     c -= m * n;
     c += 2;
     a += 2;
@@ -67,23 +94,44 @@
       const int32_t* dmap = widx_dmap;
       const uint32_t* nnzmap = nidx_nnzmap;
       size_t j = n;
-      do {
+      while (j >= 1) {
         uint32_t nnz = *nnzmap++;
-        float vacc0 = *w++;
+        float vacc0x0 = *w++;
         if XNN_LIKELY(nnz != 0) {
           do {
             const intptr_t diff = *dmap++;
             const float va0 = a[0];
             a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-            const float vb = *w++;
-            vacc0 += va0 * vb;
+            const float vb0 = *w++;
+            vacc0x0 += va0 * vb0;
           } while (--nnz != 0);
         }
-        float vout0 = math_min_f32(vacc0, vmax);
-        vout0 = math_max_f32(vout0, vmin);
-        c[0] = vout0;
-        c += m;
-      } while (--j != 0);
+        float vout0x0 = math_min_f32(vacc0x0, vmax);
+        vout0x0 = math_max_f32(vout0x0, vmin);
+        c[0 * m + 0] = vout0x0;
+        c += 1 * m;
+        j -= 1;
+      }
+      if XNN_UNLIKELY(j != 0) {
+        do {
+          uint32_t nnz = *nnzmap++;
+          float vacc0 = *w++;
+          if XNN_LIKELY(nnz != 0) {
+            do {
+              const intptr_t diff = *dmap++;
+              const float va0 = a[0];
+              a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+              const float vb = *w++;
+              vacc0 += va0 * vb;
+            } while (--nnz != 0);
+          }
+          float vout0 = math_min_f32(vacc0, vmax);
+          vout0 = math_max_f32(vout0, vmin);
+          c[0] = vout0;
+          c += m;
+          j -= 1;
+        } while (j != 0);
+      }
       c -= m * n;
       c += 1;
       a += 1;
diff --git a/src/f32-spmm/4x1-scalar.c b/src/f32-spmm/4x1-scalar.c
index 353f633..d45c518 100644
--- a/src/f32-spmm/4x1-scalar.c
+++ b/src/f32-spmm/4x1-scalar.c
@@ -33,12 +33,12 @@
     const int32_t* dmap = widx_dmap;
     const uint32_t* nnzmap = nidx_nnzmap;
     size_t j = n;
-    do {
+    while (j >= 1) {
       uint32_t nnz = *nnzmap++;
-      float vacc0 = *w++;
-      float vacc1 = vacc0;
-      float vacc2 = vacc0;
-      float vacc3 = vacc0;
+      float vacc0x0 = *w++;
+      float vacc1x0 = vacc0x0;
+      float vacc2x0 = vacc0x0;
+      float vacc3x0 = vacc0x0;
       if XNN_LIKELY(nnz != 0) {
         do {
           const intptr_t diff = *dmap++;
@@ -47,27 +47,66 @@
           const float va2 = a[2];
           const float va3 = a[3];
           a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-          const float vb = *w++;
-          vacc0 += va0 * vb;
-          vacc1 += va1 * vb;
-          vacc2 += va2 * vb;
-          vacc3 += va3 * vb;
+          const float vb0 = *w++;
+          vacc0x0 += va0 * vb0;
+          vacc1x0 += va1 * vb0;
+          vacc2x0 += va2 * vb0;
+          vacc3x0 += va3 * vb0;
         } while (--nnz != 0);
       }
-      float vout0 = math_min_f32(vacc0, vmax);
-      float vout1 = math_min_f32(vacc1, vmax);
-      float vout2 = math_min_f32(vacc2, vmax);
-      float vout3 = math_min_f32(vacc3, vmax);
-      vout0 = math_max_f32(vout0, vmin);
-      vout1 = math_max_f32(vout1, vmin);
-      vout2 = math_max_f32(vout2, vmin);
-      vout3 = math_max_f32(vout3, vmin);
-      c[0] = vout0;
-      c[1] = vout1;
-      c[2] = vout2;
-      c[3] = vout3;
-      c += m;
-    } while (--j != 0);
+      float vout0x0 = math_min_f32(vacc0x0, vmax);
+      float vout1x0 = math_min_f32(vacc1x0, vmax);
+      float vout2x0 = math_min_f32(vacc2x0, vmax);
+      float vout3x0 = math_min_f32(vacc3x0, vmax);
+      vout0x0 = math_max_f32(vout0x0, vmin);
+      vout1x0 = math_max_f32(vout1x0, vmin);
+      vout2x0 = math_max_f32(vout2x0, vmin);
+      vout3x0 = math_max_f32(vout3x0, vmin);
+      c[0 * m + 0] = vout0x0;
+      c[0 * m + 1] = vout1x0;
+      c[0 * m + 2] = vout2x0;
+      c[0 * m + 3] = vout3x0;
+      c += 1 * m;
+      j -= 1;
+    }
+    if XNN_UNLIKELY(j != 0) {
+      do {
+        uint32_t nnz = *nnzmap++;
+        float vacc0 = *w++;
+        float vacc1 = vacc0;
+        float vacc2 = vacc0;
+        float vacc3 = vacc0;
+        if XNN_LIKELY(nnz != 0) {
+          do {
+            const intptr_t diff = *dmap++;
+            const float va0 = a[0];
+            const float va1 = a[1];
+            const float va2 = a[2];
+            const float va3 = a[3];
+            a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+            const float vb = *w++;
+            vacc0 += va0 * vb;
+            vacc1 += va1 * vb;
+            vacc2 += va2 * vb;
+            vacc3 += va3 * vb;
+          } while (--nnz != 0);
+        }
+        float vout0 = math_min_f32(vacc0, vmax);
+        float vout1 = math_min_f32(vacc1, vmax);
+        float vout2 = math_min_f32(vacc2, vmax);
+        float vout3 = math_min_f32(vacc3, vmax);
+        vout0 = math_max_f32(vout0, vmin);
+        vout1 = math_max_f32(vout1, vmin);
+        vout2 = math_max_f32(vout2, vmin);
+        vout3 = math_max_f32(vout3, vmin);
+        c[0] = vout0;
+        c[1] = vout1;
+        c[2] = vout2;
+        c[3] = vout3;
+        c += m;
+        j -= 1;
+      } while (j != 0);
+    }
     c -= m * n;
     c += 4;
     a += 4;
@@ -79,29 +118,56 @@
       const int32_t* dmap = widx_dmap;
       const uint32_t* nnzmap = nidx_nnzmap;
       size_t j = n;
-      do {
+      while (j >= 1) {
         uint32_t nnz = *nnzmap++;
-        float vacc0 = *w++;
-        float vacc1 = vacc0;
+        float vacc0x0 = *w++;
+        float vacc1x0 = vacc0x0;
         if XNN_LIKELY(nnz != 0) {
           do {
             const intptr_t diff = *dmap++;
             const float va0 = a[0];
             const float va1 = a[1];
             a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-            const float vb = *w++;
-            vacc0 += va0 * vb;
-            vacc1 += va1 * vb;
+            const float vb0 = *w++;
+            vacc0x0 += va0 * vb0;
+            vacc1x0 += va1 * vb0;
           } while (--nnz != 0);
         }
-        float vout0 = math_min_f32(vacc0, vmax);
-        float vout1 = math_min_f32(vacc1, vmax);
-        vout0 = math_max_f32(vout0, vmin);
-        vout1 = math_max_f32(vout1, vmin);
-        c[0] = vout0;
-        c[1] = vout1;
-        c += m;
-      } while (--j != 0);
+        float vout0x0 = math_min_f32(vacc0x0, vmax);
+        float vout1x0 = math_min_f32(vacc1x0, vmax);
+        vout0x0 = math_max_f32(vout0x0, vmin);
+        vout1x0 = math_max_f32(vout1x0, vmin);
+        c[0 * m + 0] = vout0x0;
+        c[0 * m + 1] = vout1x0;
+        c += 1 * m;
+        j -= 1;
+      }
+      if XNN_UNLIKELY(j != 0) {
+        do {
+          uint32_t nnz = *nnzmap++;
+          float vacc0 = *w++;
+          float vacc1 = vacc0;
+          if XNN_LIKELY(nnz != 0) {
+            do {
+              const intptr_t diff = *dmap++;
+              const float va0 = a[0];
+              const float va1 = a[1];
+              a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+              const float vb = *w++;
+              vacc0 += va0 * vb;
+              vacc1 += va1 * vb;
+            } while (--nnz != 0);
+          }
+          float vout0 = math_min_f32(vacc0, vmax);
+          float vout1 = math_min_f32(vacc1, vmax);
+          vout0 = math_max_f32(vout0, vmin);
+          vout1 = math_max_f32(vout1, vmin);
+          c[0] = vout0;
+          c[1] = vout1;
+          c += m;
+          j -= 1;
+        } while (j != 0);
+      }
       c -= m * n;
       c += 2;
       a += 2;
@@ -111,23 +177,44 @@
       const int32_t* dmap = widx_dmap;
       const uint32_t* nnzmap = nidx_nnzmap;
       size_t j = n;
-      do {
+      while (j >= 1) {
         uint32_t nnz = *nnzmap++;
-        float vacc0 = *w++;
+        float vacc0x0 = *w++;
         if XNN_LIKELY(nnz != 0) {
           do {
             const intptr_t diff = *dmap++;
             const float va0 = a[0];
             a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-            const float vb = *w++;
-            vacc0 += va0 * vb;
+            const float vb0 = *w++;
+            vacc0x0 += va0 * vb0;
           } while (--nnz != 0);
         }
-        float vout0 = math_min_f32(vacc0, vmax);
-        vout0 = math_max_f32(vout0, vmin);
-        c[0] = vout0;
-        c += m;
-      } while (--j != 0);
+        float vout0x0 = math_min_f32(vacc0x0, vmax);
+        vout0x0 = math_max_f32(vout0x0, vmin);
+        c[0 * m + 0] = vout0x0;
+        c += 1 * m;
+        j -= 1;
+      }
+      if XNN_UNLIKELY(j != 0) {
+        do {
+          uint32_t nnz = *nnzmap++;
+          float vacc0 = *w++;
+          if XNN_LIKELY(nnz != 0) {
+            do {
+              const intptr_t diff = *dmap++;
+              const float va0 = a[0];
+              a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+              const float vb = *w++;
+              vacc0 += va0 * vb;
+            } while (--nnz != 0);
+          }
+          float vout0 = math_min_f32(vacc0, vmax);
+          vout0 = math_max_f32(vout0, vmin);
+          c[0] = vout0;
+          c += m;
+          j -= 1;
+        } while (j != 0);
+      }
       c -= m * n;
       c += 1;
       a += 1;
diff --git a/src/f32-spmm/8x1-scalar.c b/src/f32-spmm/8x1-scalar.c
index 2a1ac08..5574a7d 100644
--- a/src/f32-spmm/8x1-scalar.c
+++ b/src/f32-spmm/8x1-scalar.c
@@ -33,16 +33,16 @@
     const int32_t* dmap = widx_dmap;
     const uint32_t* nnzmap = nidx_nnzmap;
     size_t j = n;
-    do {
+    while (j >= 1) {
       uint32_t nnz = *nnzmap++;
-      float vacc0 = *w++;
-      float vacc1 = vacc0;
-      float vacc2 = vacc0;
-      float vacc3 = vacc0;
-      float vacc4 = vacc0;
-      float vacc5 = vacc0;
-      float vacc6 = vacc0;
-      float vacc7 = vacc0;
+      float vacc0x0 = *w++;
+      float vacc1x0 = vacc0x0;
+      float vacc2x0 = vacc0x0;
+      float vacc3x0 = vacc0x0;
+      float vacc4x0 = vacc0x0;
+      float vacc5x0 = vacc0x0;
+      float vacc6x0 = vacc0x0;
+      float vacc7x0 = vacc0x0;
       if XNN_LIKELY(nnz != 0) {
         do {
           const intptr_t diff = *dmap++;
@@ -55,43 +55,106 @@
           const float va6 = a[6];
           const float va7 = a[7];
           a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-          const float vb = *w++;
-          vacc0 += va0 * vb;
-          vacc1 += va1 * vb;
-          vacc2 += va2 * vb;
-          vacc3 += va3 * vb;
-          vacc4 += va4 * vb;
-          vacc5 += va5 * vb;
-          vacc6 += va6 * vb;
-          vacc7 += va7 * vb;
+          const float vb0 = *w++;
+          vacc0x0 += va0 * vb0;
+          vacc1x0 += va1 * vb0;
+          vacc2x0 += va2 * vb0;
+          vacc3x0 += va3 * vb0;
+          vacc4x0 += va4 * vb0;
+          vacc5x0 += va5 * vb0;
+          vacc6x0 += va6 * vb0;
+          vacc7x0 += va7 * vb0;
         } while (--nnz != 0);
       }
-      float vout0 = math_min_f32(vacc0, vmax);
-      float vout1 = math_min_f32(vacc1, vmax);
-      float vout2 = math_min_f32(vacc2, vmax);
-      float vout3 = math_min_f32(vacc3, vmax);
-      float vout4 = math_min_f32(vacc4, vmax);
-      float vout5 = math_min_f32(vacc5, vmax);
-      float vout6 = math_min_f32(vacc6, vmax);
-      float vout7 = math_min_f32(vacc7, vmax);
-      vout0 = math_max_f32(vout0, vmin);
-      vout1 = math_max_f32(vout1, vmin);
-      vout2 = math_max_f32(vout2, vmin);
-      vout3 = math_max_f32(vout3, vmin);
-      vout4 = math_max_f32(vout4, vmin);
-      vout5 = math_max_f32(vout5, vmin);
-      vout6 = math_max_f32(vout6, vmin);
-      vout7 = math_max_f32(vout7, vmin);
-      c[0] = vout0;
-      c[1] = vout1;
-      c[2] = vout2;
-      c[3] = vout3;
-      c[4] = vout4;
-      c[5] = vout5;
-      c[6] = vout6;
-      c[7] = vout7;
-      c += m;
-    } while (--j != 0);
+      float vout0x0 = math_min_f32(vacc0x0, vmax);
+      float vout1x0 = math_min_f32(vacc1x0, vmax);
+      float vout2x0 = math_min_f32(vacc2x0, vmax);
+      float vout3x0 = math_min_f32(vacc3x0, vmax);
+      float vout4x0 = math_min_f32(vacc4x0, vmax);
+      float vout5x0 = math_min_f32(vacc5x0, vmax);
+      float vout6x0 = math_min_f32(vacc6x0, vmax);
+      float vout7x0 = math_min_f32(vacc7x0, vmax);
+      vout0x0 = math_max_f32(vout0x0, vmin);
+      vout1x0 = math_max_f32(vout1x0, vmin);
+      vout2x0 = math_max_f32(vout2x0, vmin);
+      vout3x0 = math_max_f32(vout3x0, vmin);
+      vout4x0 = math_max_f32(vout4x0, vmin);
+      vout5x0 = math_max_f32(vout5x0, vmin);
+      vout6x0 = math_max_f32(vout6x0, vmin);
+      vout7x0 = math_max_f32(vout7x0, vmin);
+      c[0 * m + 0] = vout0x0;
+      c[0 * m + 1] = vout1x0;
+      c[0 * m + 2] = vout2x0;
+      c[0 * m + 3] = vout3x0;
+      c[0 * m + 4] = vout4x0;
+      c[0 * m + 5] = vout5x0;
+      c[0 * m + 6] = vout6x0;
+      c[0 * m + 7] = vout7x0;
+      c += 1 * m;
+      j -= 1;
+    }
+    if XNN_UNLIKELY(j != 0) {
+      do {
+        uint32_t nnz = *nnzmap++;
+        float vacc0 = *w++;
+        float vacc1 = vacc0;
+        float vacc2 = vacc0;
+        float vacc3 = vacc0;
+        float vacc4 = vacc0;
+        float vacc5 = vacc0;
+        float vacc6 = vacc0;
+        float vacc7 = vacc0;
+        if XNN_LIKELY(nnz != 0) {
+          do {
+            const intptr_t diff = *dmap++;
+            const float va0 = a[0];
+            const float va1 = a[1];
+            const float va2 = a[2];
+            const float va3 = a[3];
+            const float va4 = a[4];
+            const float va5 = a[5];
+            const float va6 = a[6];
+            const float va7 = a[7];
+            a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+            const float vb = *w++;
+            vacc0 += va0 * vb;
+            vacc1 += va1 * vb;
+            vacc2 += va2 * vb;
+            vacc3 += va3 * vb;
+            vacc4 += va4 * vb;
+            vacc5 += va5 * vb;
+            vacc6 += va6 * vb;
+            vacc7 += va7 * vb;
+          } while (--nnz != 0);
+        }
+        float vout0 = math_min_f32(vacc0, vmax);
+        float vout1 = math_min_f32(vacc1, vmax);
+        float vout2 = math_min_f32(vacc2, vmax);
+        float vout3 = math_min_f32(vacc3, vmax);
+        float vout4 = math_min_f32(vacc4, vmax);
+        float vout5 = math_min_f32(vacc5, vmax);
+        float vout6 = math_min_f32(vacc6, vmax);
+        float vout7 = math_min_f32(vacc7, vmax);
+        vout0 = math_max_f32(vout0, vmin);
+        vout1 = math_max_f32(vout1, vmin);
+        vout2 = math_max_f32(vout2, vmin);
+        vout3 = math_max_f32(vout3, vmin);
+        vout4 = math_max_f32(vout4, vmin);
+        vout5 = math_max_f32(vout5, vmin);
+        vout6 = math_max_f32(vout6, vmin);
+        vout7 = math_max_f32(vout7, vmin);
+        c[0] = vout0;
+        c[1] = vout1;
+        c[2] = vout2;
+        c[3] = vout3;
+        c[4] = vout4;
+        c[5] = vout5;
+        c[6] = vout6;
+        c[7] = vout7;
+        c += m;
+        j -= 1;
+      } while (j != 0);
+    }
     c -= m * n;
     c += 8;
     a += 8;
@@ -103,12 +166,12 @@
       const int32_t* dmap = widx_dmap;
       const uint32_t* nnzmap = nidx_nnzmap;
       size_t j = n;
-      do {
+      while (j >= 1) {
         uint32_t nnz = *nnzmap++;
-        float vacc0 = *w++;
-        float vacc1 = vacc0;
-        float vacc2 = vacc0;
-        float vacc3 = vacc0;
+        float vacc0x0 = *w++;
+        float vacc1x0 = vacc0x0;
+        float vacc2x0 = vacc0x0;
+        float vacc3x0 = vacc0x0;
         if XNN_LIKELY(nnz != 0) {
           do {
             const intptr_t diff = *dmap++;
@@ -117,27 +180,66 @@
             const float va2 = a[2];
             const float va3 = a[3];
             a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-            const float vb = *w++;
-            vacc0 += va0 * vb;
-            vacc1 += va1 * vb;
-            vacc2 += va2 * vb;
-            vacc3 += va3 * vb;
+            const float vb0 = *w++;
+            vacc0x0 += va0 * vb0;
+            vacc1x0 += va1 * vb0;
+            vacc2x0 += va2 * vb0;
+            vacc3x0 += va3 * vb0;
           } while (--nnz != 0);
         }
-        float vout0 = math_min_f32(vacc0, vmax);
-        float vout1 = math_min_f32(vacc1, vmax);
-        float vout2 = math_min_f32(vacc2, vmax);
-        float vout3 = math_min_f32(vacc3, vmax);
-        vout0 = math_max_f32(vout0, vmin);
-        vout1 = math_max_f32(vout1, vmin);
-        vout2 = math_max_f32(vout2, vmin);
-        vout3 = math_max_f32(vout3, vmin);
-        c[0] = vout0;
-        c[1] = vout1;
-        c[2] = vout2;
-        c[3] = vout3;
-        c += m;
-      } while (--j != 0);
+        float vout0x0 = math_min_f32(vacc0x0, vmax);
+        float vout1x0 = math_min_f32(vacc1x0, vmax);
+        float vout2x0 = math_min_f32(vacc2x0, vmax);
+        float vout3x0 = math_min_f32(vacc3x0, vmax);
+        vout0x0 = math_max_f32(vout0x0, vmin);
+        vout1x0 = math_max_f32(vout1x0, vmin);
+        vout2x0 = math_max_f32(vout2x0, vmin);
+        vout3x0 = math_max_f32(vout3x0, vmin);
+        c[0 * m + 0] = vout0x0;
+        c[0 * m + 1] = vout1x0;
+        c[0 * m + 2] = vout2x0;
+        c[0 * m + 3] = vout3x0;
+        c += 1 * m;
+        j -= 1;
+      }
+      if XNN_UNLIKELY(j != 0) {
+        do {
+          uint32_t nnz = *nnzmap++;
+          float vacc0 = *w++;
+          float vacc1 = vacc0;
+          float vacc2 = vacc0;
+          float vacc3 = vacc0;
+          if XNN_LIKELY(nnz != 0) {
+            do {
+              const intptr_t diff = *dmap++;
+              const float va0 = a[0];
+              const float va1 = a[1];
+              const float va2 = a[2];
+              const float va3 = a[3];
+              a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+              const float vb = *w++;
+              vacc0 += va0 * vb;
+              vacc1 += va1 * vb;
+              vacc2 += va2 * vb;
+              vacc3 += va3 * vb;
+            } while (--nnz != 0);
+          }
+          float vout0 = math_min_f32(vacc0, vmax);
+          float vout1 = math_min_f32(vacc1, vmax);
+          float vout2 = math_min_f32(vacc2, vmax);
+          float vout3 = math_min_f32(vacc3, vmax);
+          vout0 = math_max_f32(vout0, vmin);
+          vout1 = math_max_f32(vout1, vmin);
+          vout2 = math_max_f32(vout2, vmin);
+          vout3 = math_max_f32(vout3, vmin);
+          c[0] = vout0;
+          c[1] = vout1;
+          c[2] = vout2;
+          c[3] = vout3;
+          c += m;
+          j -= 1;
+        } while (j != 0);
+      }
       c -= m * n;
       c += 4;
       a += 4;
@@ -147,29 +249,56 @@
       const int32_t* dmap = widx_dmap;
       const uint32_t* nnzmap = nidx_nnzmap;
       size_t j = n;
-      do {
+      while (j >= 1) {
         uint32_t nnz = *nnzmap++;
-        float vacc0 = *w++;
-        float vacc1 = vacc0;
+        float vacc0x0 = *w++;
+        float vacc1x0 = vacc0x0;
         if XNN_LIKELY(nnz != 0) {
           do {
             const intptr_t diff = *dmap++;
             const float va0 = a[0];
             const float va1 = a[1];
             a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-            const float vb = *w++;
-            vacc0 += va0 * vb;
-            vacc1 += va1 * vb;
+            const float vb0 = *w++;
+            vacc0x0 += va0 * vb0;
+            vacc1x0 += va1 * vb0;
           } while (--nnz != 0);
         }
-        float vout0 = math_min_f32(vacc0, vmax);
-        float vout1 = math_min_f32(vacc1, vmax);
-        vout0 = math_max_f32(vout0, vmin);
-        vout1 = math_max_f32(vout1, vmin);
-        c[0] = vout0;
-        c[1] = vout1;
-        c += m;
-      } while (--j != 0);
+        float vout0x0 = math_min_f32(vacc0x0, vmax);
+        float vout1x0 = math_min_f32(vacc1x0, vmax);
+        vout0x0 = math_max_f32(vout0x0, vmin);
+        vout1x0 = math_max_f32(vout1x0, vmin);
+        c[0 * m + 0] = vout0x0;
+        c[0 * m + 1] = vout1x0;
+        c += 1 * m;
+        j -= 1;
+      }
+      if XNN_UNLIKELY(j != 0) {
+        do {
+          uint32_t nnz = *nnzmap++;
+          float vacc0 = *w++;
+          float vacc1 = vacc0;
+          if XNN_LIKELY(nnz != 0) {
+            do {
+              const intptr_t diff = *dmap++;
+              const float va0 = a[0];
+              const float va1 = a[1];
+              a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+              const float vb = *w++;
+              vacc0 += va0 * vb;
+              vacc1 += va1 * vb;
+            } while (--nnz != 0);
+          }
+          float vout0 = math_min_f32(vacc0, vmax);
+          float vout1 = math_min_f32(vacc1, vmax);
+          vout0 = math_max_f32(vout0, vmin);
+          vout1 = math_max_f32(vout1, vmin);
+          c[0] = vout0;
+          c[1] = vout1;
+          c += m;
+          j -= 1;
+        } while (j != 0);
+      }
       c -= m * n;
       c += 2;
       a += 2;
@@ -179,23 +308,44 @@
       const int32_t* dmap = widx_dmap;
       const uint32_t* nnzmap = nidx_nnzmap;
       size_t j = n;
-      do {
+      while (j >= 1) {
         uint32_t nnz = *nnzmap++;
-        float vacc0 = *w++;
+        float vacc0x0 = *w++;
         if XNN_LIKELY(nnz != 0) {
           do {
             const intptr_t diff = *dmap++;
             const float va0 = a[0];
             a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
-            const float vb = *w++;
-            vacc0 += va0 * vb;
+            const float vb0 = *w++;
+            vacc0x0 += va0 * vb0;
           } while (--nnz != 0);
         }
-        float vout0 = math_min_f32(vacc0, vmax);
-        vout0 = math_max_f32(vout0, vmin);
-        c[0] = vout0;
-        c += m;
-      } while (--j != 0);
+        float vout0x0 = math_min_f32(vacc0x0, vmax);
+        vout0x0 = math_max_f32(vout0x0, vmin);
+        c[0 * m + 0] = vout0x0;
+        c += 1 * m;
+        j -= 1;
+      }
+      if XNN_UNLIKELY(j != 0) {
+        do {
+          uint32_t nnz = *nnzmap++;
+          float vacc0 = *w++;
+          if XNN_LIKELY(nnz != 0) {
+            do {
+              const intptr_t diff = *dmap++;
+              const float va0 = a[0];
+              a = (const float*restrict) ((uintptr_t) a + (uintptr_t) diff);
+              const float vb = *w++;
+              vacc0 += va0 * vb;
+            } while (--nnz != 0);
+          }
+          float vout0 = math_min_f32(vacc0, vmax);
+          vout0 = math_max_f32(vout0, vmin);
+          c[0] = vout0;
+          c += m;
+          j -= 1;
+        } while (j != 0);
+      }
       c -= m * n;
       c += 1;
       a += 1;
diff --git a/test/f32-spmm.cc b/test/f32-spmm.cc
index 5c352f6..49d397f 100644
--- a/test/f32-spmm.cc
+++ b/test/f32-spmm.cc
@@ -5029,8 +5029,8 @@
   }
 }
 
-TEST(F32_SPMM_8X2__SCALAR, n_gt_1) {
-  for (uint32_t n = 2; n < 10; n++) {
+TEST(F32_SPMM_8X2__SCALAR, n_gt_2) {
+  for (uint32_t n = 3; n < 10; n++) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5044,9 +5044,23 @@
   }
 }
 
+TEST(F32_SPMM_8X2__SCALAR, n_div_2) {
+  for (uint32_t n = 4; n <= 6; n += 2) {
+    for (size_t k = 1; k <= 5; k += 2) {
+      SpMMMicrokernelTester()
+        .mr(8)
+        .nr(2)
+        .m(8)
+        .n(n)
+        .k(k)
+        .Test(xnn_f32_spmm_ukernel_8x2__scalar, SpMMMicrokernelTester::Variant::Scalar);
+    }
+  }
+}
+
 TEST(F32_SPMM_8X2__SCALAR, m_lt_8) {
   for (uint32_t m = 1; m < 8; m++) {
-    for (uint32_t n = 1; n < 10; n += 2) {
+    for (uint32_t n = 1; n < 10; n += 3) {
       for (size_t k = 1; k <= 5; k += 2) {
         SpMMMicrokernelTester()
           .mr(8)
@@ -5063,7 +5077,7 @@
 
 TEST(F32_SPMM_8X2__SCALAR, m_div_8) {
   for (uint32_t m = 16; m <= 24; m += 8) {
-    for (uint32_t n = 1; n < 10; n += 2) {
+    for (uint32_t n = 1; n < 10; n += 3) {
       for (size_t k = 1; k <= 5; k += 2) {
         SpMMMicrokernelTester()
           .mr(8)
@@ -5080,7 +5094,7 @@
 
 TEST(F32_SPMM_8X2__SCALAR, m_gt_8) {
   for (uint32_t m = 9; m < 16; m++) {
-    for (uint32_t n = 1; n < 10; n += 2) {
+    for (uint32_t n = 1; n < 10; n += 3) {
       for (size_t k = 1; k <= 5; k += 2) {
         SpMMMicrokernelTester()
           .mr(8)
@@ -5096,7 +5110,7 @@
 }
 
 TEST(F32_SPMM_8X2__SCALAR, qmin) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 10; n += 3) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5112,7 +5126,7 @@
 }
 
 TEST(F32_SPMM_8X2__SCALAR, qmax) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 10; n += 3) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5128,7 +5142,7 @@
 }
 
 TEST(F32_SPMM_8X2__SCALAR, half_sparse) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 10; n += 3) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5143,7 +5157,7 @@
 }
 
 TEST(F32_SPMM_8X2__SCALAR, zero_weights) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 10; n += 3) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5162,7 +5176,7 @@
     .mr(8)
     .nr(4)
     .m(8)
-    .n(2)
+    .n(4)
     .k(1)
     .sparsity(0.0f)
     .Test(xnn_f32_spmm_ukernel_8x4__scalar, SpMMMicrokernelTester::Variant::Scalar);
@@ -5209,8 +5223,8 @@
   }
 }
 
-TEST(F32_SPMM_8X4__SCALAR, n_gt_1) {
-  for (uint32_t n = 2; n < 10; n++) {
+TEST(F32_SPMM_8X4__SCALAR, n_gt_4) {
+  for (uint32_t n = 5; n < 10; n++) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5224,9 +5238,23 @@
   }
 }
 
+TEST(F32_SPMM_8X4__SCALAR, n_div_4) {
+  for (uint32_t n = 8; n <= 12; n += 4) {
+    for (size_t k = 1; k <= 5; k += 2) {
+      SpMMMicrokernelTester()
+        .mr(8)
+        .nr(4)
+        .m(8)
+        .n(n)
+        .k(k)
+        .Test(xnn_f32_spmm_ukernel_8x4__scalar, SpMMMicrokernelTester::Variant::Scalar);
+    }
+  }
+}
+
 TEST(F32_SPMM_8X4__SCALAR, m_lt_8) {
   for (uint32_t m = 1; m < 8; m++) {
-    for (uint32_t n = 1; n < 10; n += 2) {
+    for (uint32_t n = 1; n < 20; n += 5) {
       for (size_t k = 1; k <= 5; k += 2) {
         SpMMMicrokernelTester()
           .mr(8)
@@ -5243,7 +5271,7 @@
 
 TEST(F32_SPMM_8X4__SCALAR, m_div_8) {
   for (uint32_t m = 16; m <= 24; m += 8) {
-    for (uint32_t n = 1; n < 10; n += 2) {
+    for (uint32_t n = 1; n < 20; n += 5) {
       for (size_t k = 1; k <= 5; k += 2) {
         SpMMMicrokernelTester()
           .mr(8)
@@ -5260,7 +5288,7 @@
 
 TEST(F32_SPMM_8X4__SCALAR, m_gt_8) {
   for (uint32_t m = 9; m < 16; m++) {
-    for (uint32_t n = 1; n < 10; n += 2) {
+    for (uint32_t n = 1; n < 20; n += 5) {
       for (size_t k = 1; k <= 5; k += 2) {
         SpMMMicrokernelTester()
           .mr(8)
@@ -5276,7 +5304,7 @@
 }
 
 TEST(F32_SPMM_8X4__SCALAR, qmin) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 20; n += 5) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5292,7 +5320,7 @@
 }
 
 TEST(F32_SPMM_8X4__SCALAR, qmax) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 20; n += 5) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5308,7 +5336,7 @@
 }
 
 TEST(F32_SPMM_8X4__SCALAR, half_sparse) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 20; n += 5) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5323,7 +5351,7 @@
 }
 
 TEST(F32_SPMM_8X4__SCALAR, zero_weights) {
-  for (uint32_t n = 1; n < 10; n += 2) {
+  for (uint32_t n = 1; n < 20; n += 5) {
     for (size_t k = 1; k <= 5; k += 2) {
       SpMMMicrokernelTester()
         .mr(8)
@@ -5335,4 +5363,4 @@
         .Test(xnn_f32_spmm_ukernel_8x4__scalar, SpMMMicrokernelTester::Variant::Scalar);
     }
   }
-}
+}
\ No newline at end of file