[RFR]: 8186578: Zero fails to build on linux-sparc due to sparc-specific code

[David Holmes]

Hi Adrian,

These changes seem fine to me. I will sponsor this for you once we have 
a second reviewer. If there are any issues with Solaris builds I'll find 
them and come back to you. :)

Thanks,
David

On 23/08/2017 10:23 PM, John Paul Adrian Glaubitz wrote:
> Hi!
> 
> Currently, it's not possible to build Zero on linux-sparc as there are two
> instances in the code where sparc-specific code being included or linked
> against which is not available in the Zero build builds.
> 
> The first instance is in src/share/vm/compiler/oopMap.cpp:
> 
>   #ifdef SPARC
>   #include "vmreg_sparc.inline.hpp"
>   #endif
> 
> As it turns out, the header is not actually required in oooMap.cpp for
> native builds. None of the symbols defined in there are used in oooMap.cpp
> and my test builds showed that both on linux-sparc (native) as well
> as solaris-sparc the header doesn't seem to be necessary. However, while
> I was able to build on linux-sparc without any problems, I was unable
> to build on solaris-sparc - with or without the header removed. So, this
> should be reviewed by a OpenJDK Solaris developer just to be sure.
> 
> The second instance is in 
> src/share/vm/gc/shared/memset_with_concurrent_readers.hpp:
> 
> #ifdef SPARC
> 
> // SPARC requires special handling.  See SPARC-specific definition.
> 
> #else
> // All others just use memset.
> 
> inline void memset_with_concurrent_readers(void* to, int value, size_t 
> size) {
>    ::memset(to, value, size);
> }
> 
> #endif // End of target dispatch.
> 
> The definition here comes from 
> ./src/cpu/sparc/vm/memset_with_concurrent_readers_sparc.cpp
> when compiling on sparc. However, when building Zero, this particular 
> source
> is not built and hence memset_with_concurrent_readers is not available when
> building Zero on sparc. In this case, I just decided not to use the
> sparc version when ZERO is defined.
> 
> Webrev for the suggested changes in [1].
> 
> Adrian
> 
>> [1] http://cr.openjdk.java.net/~glaubitz/8186578/webrev.00/
>