import upstream maccel baseline

driver/utils.h

@@ -0,0 +1,28 @@
+#ifndef _UTILS_H_
+#define _UTILS_H_
+
+#ifdef __KERNEL__
+#include <linux/types.h>
+#else
+#include <stdint.h>
+#endif
+
+#include "dbg.h"
+
+static inline int64_t div128_s64_s64_s64(int64_t high, int64_t low,
+                                         int64_t divisor) {
+  int64_t result;
+  // s.high.low
+  // high -> rdx
+  // low -> rax
+  uint64_t remainder;
+  __asm__("idivq %[B]"
+          : "=a"(result), "=d"(remainder)
+          : [B] "r"(divisor), "a"(low), "d"(high));
+
+  return result;
+}
+
+static inline int is_digit(char c) { return '0' <= c && c <= '9'; }
+
+#endif