metal : block_q_n_dot_y for block_q5_0 (broken)

Author: jhen0409

ggml-metal.metal

@@ -447,7 +447,17 @@ inline float block_q_n_dot_y(device const block_q4_1 * qb_curr, float sumy, thre
 // we assume that the yl's have been multiplied with the appropriate scale factor
 // that corresponds to the missing bit shifts (1, 1/16, 1/256, 1/4096)
 inline float block_q_n_dot_y(device const block_q5_0 * qb_curr, float sumy, thread float * yl, int il) {
-    // TODO
+    float d = qb_curr->d;
+    float2 acc = 0.f;
+    device const uint16_t * qs = ((device const uint16_t *)qb_curr + 3 + il/2);
+    const uint32_t qh = *((device const uint32_t *)qb_curr->qh);
+    for (int i = 0; i < 8; i+=2) {
+        acc[0] += yl[i + 0] * ((qs[i / 2] & 0x000F) | ((qh >> (i+0+il        ) << 4 ) & 0x0010))
+                + yl[i + 1] * ((qs[i / 2] & 0x0F00) | ((qh >> (i+1+il        ) << 12) & 0x1000));
+        acc[1] += yl[i + 8] * ((qs[i / 2] & 0x00F0) | ((qh >> (i+0+il+QK5_0/2) << 4 ) & 0x0010))
+                + yl[i + 9] * ((qs[i / 2] & 0xF000) | ((qh >> (i+1+il+QK5_0/2) << 12) & 0x1000));
+    }
+    return d * (sumy * -16.f + acc[0] + acc[1]);
 }
 
 // function for calculate inner product between half a q5_1 block and 16 floats (yl), sumy is SUM(yl[i])
@@ -2225,13 +2235,13 @@ void dequantize_q5_0(device const block_q5_0 *xb, short il, thread type4x4 & reg
 
     const int x_mv = (il ? 4 : 0);
 
-    const int gh_mv = (il ? 12 : 0);
-    const int gh_bk = (il ? 0 : 4);
+    const int qh_mv = (il ? 12 : 0);
+    const int qh_bk = (il ? 0 : 4);
 
     for (int i = 0; i < 8; i++) {
         // extract the 5-th bits for x0 and x1
-        const uint8_t xh_0 = ((qh >> (gh_mv + 2*i  )) << gh_bk) & 0x10;
-        const uint8_t xh_1 = ((qh >> (gh_mv + 2*i+1)) << gh_bk) & 0x10;
+        const uint8_t xh_0 = ((qh >> (qh_mv + 2*i  )) << qh_bk) & 0x10;
+        const uint8_t xh_1 = ((qh >> (qh_mv + 2*i+1)) << qh_bk) & 0x10;
 
         // combine the 4-bits from qs with the 5th bit
         const int32_t x0 = (((qs[i] & mask) >> x_mv) | xh_0);