RFR: 8230664: Fix TestInstanceKlassSize for PowerPC [v3]

Ziviani github.com+670087+jrziviani at openjdk.java.net
Thu Oct 1 16:20:12 UTC 2020


> TestInstanceKlassSize was failing because, for PowerPC, the following code (instanceKlass.cpp) always compiles to
> `return false;` bool InstanceKlass::has_stored_fingerprint() const {
> #if INCLUDE_AOT
>   return should_store_fingerprint() || is_shared();
> #else
>   return false;
> #endif
> }
> However, in `hasStoredFingerprint()@InstanceKlass.java` the condition `shouldStoreFingerprint() || isShared();` is
> always evaluated and may return true (_AFAIK isShared() returns true_). Such condition adds 8 bytes in the
> `getSize()@InstanceKlass.java` causing the failure in TestInstanceKlassSize: public long getSize() { // in number of
> bytes
>   ...
>   if (hasStoredFingerprint()) {
>     size += 8; // uint64_t
>   }
>   return alignSize(size);
> }
> Considering these tests are failing for PowerPC only (_based on ProblemList.txt_), my solution checks if
> `hasStoredFingerprint()` is running on a PowerPC platform. I decided to go this way because there is no existing flag
> informing whether AOT is included or not and creating a new one just to handle the PowerPC case seems too much.  This
> patch is an attempt to fix https://bugs.openjdk.java.net/browse/JDK-8230664

Ziviani has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains
one commit:

  8253900: SA: wrong size computation when JVM was built without AOT
  
  The code hasStoredFingerprint() at InstanceKlass.java is not considering
  AOT disabled at compilation time, like has_stored_fingerprint() at
  instanceKlass.cpp does. Such difference can cause TestInstanceKlassSize
  failures because all objects will have an extra 8-bytes.

-------------

Changes: https://git.openjdk.java.net/jdk/pull/358/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=358&range=02
  Stats: 32 lines in 6 files changed: 29 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/358.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/358/head:pull/358

PR: https://git.openjdk.java.net/jdk/pull/358


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