RFR(S): 8192825: PPC64: Missing null check in C1 inline cache check

[Lindenmaier, Goetz]

Hi Martin, 

thanks for fixing this, looks good.

Best regards,
  Goetz.

> -----Original Message-----
> From: Doerr, Martin
> Sent: Donnerstag, 30. November 2017 18:17
> To: 'hotspot-compiler-dev at openjdk.java.net' <hotspot-compiler-
> dev at openjdk.java.net>; Lindenmaier, Goetz <goetz.lindenmaier at sap.com>
> Subject: RFR(S): 8192825: PPC64: Missing null check in C1 inline cache check
> 
> Hi,
> 
> 
> 
> I found a problem on AIX which is cause by a missing null check.
> 
> 
> 
> Compiled methods need to perform a null check in the unverified entry. This
> is usually done implicitly by loading the Klass*.
> 
> However, implicit null checks may be off on PPC64 (especially on AIX where
> the 0 page is readable).
> 
> 
> 
> Null checks are especially needed after:
> 
> 8160543: C1: Crash in java.lang.String.indexOf in some java.sql tests
> 
> Summary: C1 must use unverified entry point for unloaded methods.
> 
> 
> 
> Webrev is here:
> 
> http://cr.openjdk.java.net/~mdoerr/8192825_PPC64_C1_ic_nullcheck/webr
> ev.00/
> 
> 
> 
> Please review.
> 
> 
> 
> Best regards,
> 
> Martin
> 
>