Merge pull request #1398 from Adenilson/bigInt01

Optimize harfbuzz big integer conversions

src/hb-machinery.hh

@@ -721,6 +721,12 @@ struct BEInt<Type, 2>
   }
   inline operator Type (void) const
   {
+#if defined(__GNUC__) || defined(__clang__)
+    /* Spoon-feed the compiler a big-endian integer with alignment 1.
+     * https://github.com/harfbuzz/harfbuzz/pull/1398 */
+    struct __attribute__((packed)) packed_uint16_t { uint16_t v; };
+    return __builtin_bswap16 (((packed_uint16_t *) this)->v);
+#endif
     return (v[0] <<  8)
          + (v[1]      );
   }