RFR(M): 8139040: Fix initializations before ShouldNotReachHere()

[Coleen Phillimore]

I had to add one more initialization for some internal platform for some 
reason I don't quite know.   See threadService.hpp.

open webrev at http://cr.openjdk.java.net/~coleenp/8139040.01/


Coleen

On 10/20/15 3:24 AM, Lindenmaier, Goetz wrote:
> Hi David,
>
> yes, I assume the compiler optimizes it.
> If the compiler issues a warning, it has all information it needs to
> optimize it.  So I'm sure gcc does so.  I don't know about the solaris
> compiler, though.
>
> Other locations in that file also initialize at the declaration
> (e.g., c1_LIRAssembler_x86.cpp:3917).
> I fixed these two anyways:
> http://cr.openjdk.java.net/~goetz/webrevs/8139040-init/webrev.05/
>
> Best regards,
>    Goetz.
>
>
>> -----Original Message-----
>> From: hotspot-runtime-dev [mailto:hotspot-runtime-dev-
>> bounces at openjdk.java.net] On Behalf Of David Holmes
>> Sent: Dienstag, 20. Oktober 2015 02:46
>> To: hotspot-runtime-dev at openjdk.java.net
>> Subject: Re: RFR(M): 8139040: Fix initializations before
>> ShouldNotReachHere()
>>
>> Hi Goetz,
>>
>> src/cpu/x86/vm/c1_LIRAssembler_x86.cpp
>>
>> I'd prefer to see the missing initialization added to the default of the
>> switch:
>>
>> !   Assembler::Condition acond = Assembler::equal, ncond =
>> Assembler::notEqual;
>>       switch (condition) {
>>
>> otherwise we're just wasting instructions (or assuming the compiler will
>> optimize it away).
>>
>> Same with:
>>
>> 3189   Address::ScaleFactor scale = Address::no_scale;
>>
>> More generally if something is complaining about an uninitialized
>> variable on a ShouldNotReachHere/fatal path then put the initialization
>> in that path, not the common code that will cause it to be unnecessarily
>> executed.
>>
>> Cheers,
>> David