codestrings gtest fails on AArch64: "udf" in padding

On hsdis-enabled machine this test fails even with JDK-8274039:

$ CONF=linux-aarch64-server-fastdebug make run-test TEST=jtreg:gtest/GTestWrapper.java

[----------] 1 test from codestrings
[ RUN ] codestrings.validate_vm
/home/shade/shipilev-jdk/test/hotspot/gtest/code/test_codestrings.cpp:85: Failure
Expected equality of these values:
  replace_addr_expr(out1.as_string())
    Which is: "--------------------------------------------------------------------------------\n ;; First block comment.\n <addr>: nop\n--------------------------------------------------------------------------------\n"
  replace_addr_expr(out2.as_string())
    Which is: "--------------------------------------------------------------------------------\n ;; First block comment.\n <addr>: nop\n <addr>: udf\t#0\n--------------------------------------------------------------------------------\n"
With diff:
@@ +2,4 @@
  ;; First block comment.
   <addr>: nop
+ <addr>: udf\t#0
 --------------------------------------------------------------------------------\n