1 files changed, 39 insertions, 0 deletions
diff --git a/csrc/common.cpp b/csrc/common.cpp
new file mode 100644
index 0000000..972602b
--- /dev/null
+++ b/csrc/common.cpp
@@ -0,0 +1,39 @@
+#include <common.h>
+#include <float.h>
+
+void *quantize_block(void *arguments) {
+    // 1. find absmax in block
+    // 2. divide input value by absmax to normalize into [-1.0, 1.0]
+    // 3. do binary search to find the closest value
+    // 4. check minimal distance
+    // 5. store index
+
+    struct quantize_block_args *args = (quantize_block_args *) arguments;
+
+    // 1. find absmax in block
+    float absmax_block = -FLT_MAX;
+    for (int i = args->block_idx; i < args->block_end; i++)
+        absmax_block = fmax(absmax_block, fabs(args->A[i]));
+
+    args->absmax[args->block_idx / BLOCK_SIZE] = absmax_block;
+
+    for (int i = args->block_idx; i < args->block_end; i++) {
+        // 2. divide input value by absmax to normalize into [-1.0, 1.0]
+        // 3. do binary search to find the closest value
+        float normed_value = args->A[i] / absmax_block;
+        int idx = args->bin_searcher->scalar(normed_value);
+
+        // 4. check minimal distance
+        // The binary search returns always the value to the left, which might not be the closest value
+        if (idx < 255) {
+            float dist_left = fabs(normed_value - (args->code[idx]));
+            float dist_right = fabs(normed_value - (args->code[idx + 1]));
+            if (dist_right < dist_left) { idx += 1; }
+        }
+
+        // 5. store index
+        args->out[i] = (unsigned char) idx;
+    }
+
+    return NULL;
+}