RFR: 8244224: Implementation of JEP 381: Remove the Solaris and SPARC Ports (hotspot)

[Mikael Vidstedt]

Kim, thank you for the review! Comments inline..


> On May 4, 2020, at 3:47 AM, Kim Barrett <kim.barrett at oracle.com> wrote:
> 
>> On May 4, 2020, at 1:12 AM, Mikael Vidstedt <mikael.vidstedt at oracle.com> wrote:
>> 
>> 
>> Please review this change which implements part of JEP 381:
>> 
>> JBS: https://bugs.openjdk.java.net/browse/JDK-8244224
>> webrev: http://cr.openjdk.java.net/~mikael/webrevs/8244224/webrev.00/hotspot/open/webrev/
>> JEP: https://bugs.openjdk.java.net/browse/JDK-8241787
> 
> I've only looked at the src/hotspot changes so far. I've not
> duplicated comments already made by Stefan.
> 
> Looks good, other than a few very minor issues, some of which might
> already be covered by planned followup RFEs.
> 
> ------------------------------------------------------------------------------
> 
> I think with sparc removal, c1's pack64/unpack64 stuff is no longer
> used.  So I think that can be removed from c1_LIR.[ch]pp too.

Good catch. Fixed.

> ------------------------------------------------------------------------------
> src/hotspot/share/opto/generateOptoStub.cpp
> 225   // Clear last_Java_pc and (optionally)_flags
> 
> The sparc-specific clearing of "flags" is gone.

Fixed.

> ------------------------------------------------------------------------------
> src/hotspot/share/runtime/deoptimization.cpp
> 1086       *((jlong *) check_alignment_get_addr(obj, index, 8)) = (jlong) *((jlong *) &val);
> 
> [pre-existing]
> The rhs cast to jlong is unnecessary, since it's dereferencing a jlong*.

When I first updated the code I actually remove the cast, but it just ended up looking asymmetrical so I chose to leave it there. Let me know if you feel strongly that it should go. (I don’t like these casts in general).

> ------------------------------------------------------------------------------
> src/hotspot/share/runtime/flags/jvmFlagConstraintsCompiler.cpp
> 236 JVMFlag::Error CompilerThreadPriorityConstraintFunc(intx value, bool verbose) {
> 237   return JVMFlag::SUCCESS;
> 238 }
> 
> After SOLARIS code removal we no longer need this constraint function.

Fixed. (I had that on my follow-up list, but included it in the upcoming webrev.)

> ------------------------------------------------------------------------------
> src/hotspot/share/runtime/globals.hpp
> 2392   experimental(size_t, ArrayAllocatorMallocLimit,                           \
> 2393           (size_t)-1,                                                       \
> 
> Combine these lines.

Fixed.

> ------------------------------------------------------------------------------
> src/hotspot/share/utilities/dtrace.hpp
> 
> Shuold just eliminate all traces of HS_DTRACE_WORKAROUND_TAIL_CALL_BUG.

Fixed - more code removed!

Cheers,
Mikael