Page-align buffers used by Metal

ggml.c

@@ -20,6 +20,7 @@
 #include <stdio.h>
 #include <float.h>
 #include <limits.h>
+#include <unistd.h>
 
 // if C99 - static_assert is noop
 // ref: https://stackoverflow.com/a/53923785/4039976
@@ -121,7 +122,11 @@ typedef void* thread_ret_t;
 #else
 inline static void* ggml_aligned_malloc(size_t size) {
     void* aligned_memory = NULL;
+#ifdef GGML_USE_METAL
+    int result = posix_memalign(&aligned_memory, getpagesize(), size);
+#else
     int result = posix_memalign(&aligned_memory, GGML_MEM_ALIGN, size);
+#endif
     if (result != 0) {
         // Handle allocation failure
         return NULL;

llama-util.h

@@ -405,13 +405,29 @@ struct llama_buffer {
     llama_buffer() = default;
 
     void resize(size_t len) {
+#ifdef GGML_USE_METAL
+        free(addr);
+        int result = posix_memalign((void **) &addr, getpagesize(), len);
+        if (result == 0) {
+            memset(addr, 0, len);
+        } 
+        else {
+            addr = NULL;
+        }
+#else
         delete[] addr;
         addr = new uint8_t[len];
+#endif
         size = len;
     }
 
     ~llama_buffer() {
+#ifdef GGML_USE_METAL
+        free(addr);
+#else
         delete[] addr;
+#endif
+        addr = NULL;
     }
 
     // disable copy and move