[13]RFR: 8226627: assert(t->singleton()) failed: must be a constant

[Jamsheed]

Hi Pengfei Li,

On 02/07/19 12:19 PM, Pengfei Li (Arm Technology China) wrote:
> Hi Jamsheed,
>
> Thanks for finding this issue. Regarding on your question in https://bugs.openjdk.java.net/browse/JDK-8226627
>
>> constant cases were disabled for this intrinsics. but still some cases it found later to be constants and tried to fold.
>> i tried implementing constant folding here [1] . but real fix should be to check why constant folding is disabled at first place. and do necessary actions.
>> [1] http://cr.openjdk.java.net/~jcm/8226627/webrev/ (some typos, updated inplace)
> Constant folding for MinFD/MaxFD was left unimplemented just because we didn't know it's mandatory and it's a bit complex to handle +inf/-inf/NaN.

Thank you for confirming. In my code i don't handle infinity case 
specially, will that need to be done?(i assumed  [-inf  +inf] and their 
comparison will just work fine)

> I'm not a reviewer but I could help test your code now.
Thank you once again!

Best regards,

Jamsheed

>
> --
> Thanks,
> Pengfei
>
>> -----Original Message-----
>> From: Jamsheed <jamsheed.c.m at oracle.com>
>> Sent: Tuesday, July 2, 2019 14:24
>> To: hotspot-compiler-dev at openjdk.java.net; Pengfei Li (Arm Technology
>> China) <Pengfei.Li at arm.com>; Andrew Haley <aph at redhat.com>
>> Subject: Re: [13]RFR: 8226627: assert(t->singleton()) failed: must be a
>> constant
>>
>> Hi Pengfei Li,  Andrew Haley,
>>
>> could you please share your thoughts on this.
>>
>> ( i had CC'ed  in initial mail, but somehow it doesn't work well)
>>
>> Best regards,
>>
>> Jamsheed
>>
>> On 01/07/19 10:48 AM, Jamsheed wrote:
>>> Hi,
>>>
>>> Request for review.
>>>
>>> with 8212043, new nodes were added for MaxFD,MinFD, from mails it
>>> seems like constant folding part was not implemented and was partially
>>> disabled here[1].
>>>
>>> implemented constant folding for MaxFD, MinFD
>>>
>>> webrev: http://cr.openjdk.java.net/~jcm/8226627/webrev.00/
>>>
>>> bug: https://bugs.openjdk.java.net/browse/JDK-8226627
>>>
>>> testing: mach1-5, mach1-5(-XX:CompileThresholdScaling=0.1) mach5
>>> (hs-precheckin-comp).
>>>
>>> Best regards,
>>>
>>> Jamsheed
>>>
>>> [1]http://hg.openjdk.java.net/jdk/jdk/file/5ce081828739/src/hotspot/sh
>>> are/opto/library_call.cpp#l6709
>>>
>>>