RFR: 8203288: PPC64 and s390 fail to build after JDK-8199712 (Flight Recorder)

[Doerr, Martin]

Hi Aleksey,

PPC and s390 can perform unaligned accesses. I think we could also use UseUnalignedAccesses for this function.
But I have changed the code to tread PPC and s390 like the Intel/AMD platforms.

I have also fixed the AIX build.

Please review:
http://cr.openjdk.java.net/~mdoerr/8203288_ppc64_s390_build/webrev.01/

Best regards,
Martin


-----Original Message-----
From: Aleksey Shipilev [mailto:shade at redhat.com] 
Sent: Mittwoch, 16. Mai 2018 18:43
To: Doerr, Martin <martin.doerr at sap.com>; hotspot-dev developers (hotspot-dev at openjdk.java.net) <hotspot-dev at openjdk.java.net>
Cc: Thomas Stüfe <thomas.stuefe at gmail.com>; John Paul Adrian Glaubitz <glaubitz at physik.fu-berlin.de>
Subject: Re: RFR: 8203288: PPC64 and s390 fail to build after JDK-8199712 (Flight Recorder)

On 05/16/2018 06:29 PM, Doerr, Martin wrote:
> I have used --disable-warnings-as-errors as workaround. Maybe I can fix the warning tomorrow, too.

That warning is fixable on both PPC64 and S390 with "just":

diff -r 708db0a05b27 src/hotspot/share/jfr/utilities/jfrBigEndian.hpp
--- a/src/hotspot/share/jfr/utilities/jfrBigEndian.hpp	Wed May 16 16:34:52 2018 +0200
+++ b/src/hotspot/share/jfr/utilities/jfrBigEndian.hpp	Wed May 16 18:42:53 2018 +0200
@@ -102,7 +102,7 @@
 inline bool JfrBigEndian::platform_supports_unaligned_reads(void) {
 #if defined(IA32) || defined(AMD64)
   return true;
-#elif defined(SPARC) || defined(ARM) || defined(AARCH64)
+#elif defined(SPARC) || defined(ARM) || defined(AARCH64) || defined(PPC64) || defined(S390)
   return false;
 #else
   #warning "Unconfigured platform"


...which returns the same "false" as the default/warned path, and it fixes normal builds.

Thanks,
-Aleksey