update expected values

testsuite/tests/ghc-regress/perf/should_run/all.T

@@ -50,11 +50,11 @@ test('T3738',
       # expected value: 12800 (x86/OS X):
       if_wordsize(32,
           stats_num_field('bytes allocated', 12700,
-                                             12900)),
+                                             14000)),
       if_wordsize(64,
           stats_num_field('bytes allocated', 60000,
-                                             61000)),
-                                     # expected value: 60368 (amd64/Linux)
+                                             80000)),
+                                     # expected value: 72608 (amd64/Linux)
       only_ways(['normal'])
       ],
      compile_and_run,