RFR(S): 8206459: [s390] Prevent restoring incorrect bcp and locals in interpreter and avoid incorrect size of partialSubtypeCheckNode in C2

[Lindenmaier, Goetz]

Hi Martin, 

good catch, looks good.

Best regards,
  Goetz.


> -----Original Message-----
> From: Doerr, Martin
> Sent: Freitag, 6. Juli 2018 14:59
> To: hotspot-runtime-dev at openjdk.java.net; Lindenmaier, Goetz
> <goetz.lindenmaier at sap.com>
> Subject: RFR(S): 8206459: [s390] Prevent restoring incorrect bcp and locals in
> interpreter and avoid incorrect size of partialSubtypeCheckNode in C2
> 
> Hi,
> 
> 
> 
> TestInterfaceMethodSelection has shown a bug in the template interpreter
> on s390. Restore functions for locals (R12 = Z_tmp_3) and bcp (R13 =
> Z_tmp_4) are used without having saved the correct values.
> 
> In addition, C2 currently uses a constant size for partialSubtypeCheckNode
> which uses load_const_optimized with variable size.
> 
> 
> 
> We can simply preserve these 2 registers and remove the restore function
> calls. Webrev:
> 
> http://cr.openjdk.java.net/~mdoerr/8206459_s390_fixes/webrev.00/
> 
> 
> 
> Please review.
> 
> 
> 
> Best regards,
> 
> Martin
> 
>