RFR(M): 8195776: [x86,sparc] A row of minor fixes and enhancements.

[Lindenmaier, Goetz]

Hi Vladimir, 

thanks for looking at my change.
Our nightly testing is ok, just shows the issues of Kim's change in 
the jck test suite which are on all platforms. 
hotspot and jdk jtreg tests are all green.

Best regards,
  Goetz.



> -----Original Message-----
> From: Vladimir Kozlov [mailto:vladimir.kozlov at oracle.com]
> Sent: Samstag, 20. Januar 2018 01:34
> To: Lindenmaier, Goetz <goetz.lindenmaier at sap.com>; hs-comp-dev
> <hotspot-compiler-dev at openjdk.java.net>
> Subject: Re: RFR(M): 8195776: [x86,sparc] A row of minor fixes and
> enhancements.
> 
> Thank you, Goetz
> 
> On 1/19/18 8:31 AM, Lindenmaier, Goetz wrote:
> > Hi,
> >
> > I would like to contribute a row of smaller fixes to these two platforms.
> > These are fixes that were done by us inhouse in the past years.
> >
> > Please review. I please need a sponsor.
> > http://cr.openjdk.java.net/~goetz/wr18/8195776-
> x86SmallFixes/webrev.01
> >
> > Some details:
> >
> > Move null check info before load LIR_Assembler::emit_alloc_obj. Doesn't
> make sense after it where it was followed by a non-storage access
> instruction.
> 
> Yes, it looks like bug but we never hit it because we should not pass NULL as
> klass to allocation.
> 
> >
> > c1 on x86: fix for assertion hit when running with -XX:-ImplicitDiv0Checks
> > Symptom1: assert(info->_oop_map == oop_map, "same CodeEmitInfo
> used for multiple LIR instructions");
> > Symptom2: DivByZeroStub was emitted twice per idiv/irem
> > Fix1: create the lir_idiv without debug info (CodeEmitInfo*). When running
> with -XX:-ImplicitDiv0Checks the actual idiv cannot trap or reach a safepoint.
> > Fix2: don't call add_debug_info_for_div0() in the lir assembler. It adds
> another DivByZeroStub to the stub list.
> 
> Okay
> 
> >
> > compiledIC:
> > Data / destination can be reloaded if not volatile causing assertion to fire.
> 
> okay
> 
> >
> > stub_Generator:
> > A small optimization for G1: Only call static_write_ref_array_pre from array
> copy stubs if G1 marking is active.
> 
> make sense
> 
> >
> > Fix datatypes of flags in platform xx_globals_<cpu>.hpp files.
> 
> okay
> 
> >
> > Tests of this change will run tonight on all the platforms we build. (hotspot
> jtreg, jck and a row of bigger tests).
> 
> I submitted our testing.
> 
> Thanks,
> Vladimir
> 
> >
> > Best regards,
> >    Goetz.
> >