factor analysis code out of codegen

src/buffer.cpp

@@ -45,3 +45,20 @@ void buf_appendf(Buf *buf, const char *format, ...) {
     va_end(ap2);
     va_end(ap);
 }
+
+// these functions are not static inline so they can be better used as template parameters
+bool buf_eql_buf(Buf *buf, Buf *other) {
+    assert(buf->list.length);
+    return buf_eql_mem(buf, buf_ptr(other), buf_len(other));
+}
+
+uint32_t buf_hash(Buf *buf) {
+    assert(buf->list.length);
+    // FNV 32-bit hash
+    uint32_t h = 2166136261;
+    for (int i = 0; i < buf_len(buf); i += 1) {
+        h = h ^ ((uint8_t)buf->list.at(i));
+        h = h * 16777619;
+    }
+    return h;
+}