[10] RFR: 8016470: AllocatePrefetchDistance is not changed by command line

[Tobias Hartmann]

Hi Rahul,

here are some comments:

vm_version_x86.cpp
- remove the line break in line 1297
- adjust the indentation in lines 1306 and 1315 (one whitespace missing)

vm_version_x86.hpp
- remove the line break in line 829
- the if in line 831 could be merged with the else to "else if"

In general, when changing the default value for a flag, shouldn't we use FLAG_SET_DEFAULT?

Best regards,
Tobias

On 06.06.2017 14:27, Rahul Raghavan wrote:
> Hi,
> 
> Please review the following fix proposal:
> 
> <webrev.00> - http://cr.openjdk.java.net/~rraghavan/8016470/webrev.00/
>     src/cpu/arm/vm/vm_version_arm_32.cpp    - 3 lines changed: 2 ins; 0 del; 1 mod 
>     src/cpu/arm/vm/vm_version_arm_64.cpp    - 3 lines changed: 2 ins; 0 del; 1 mod 
>     src/cpu/x86/vm/vm_version_x86.cpp             - 16 lines changed: 11 ins; 0 del; 5 mod 
>     src/cpu/x86/vm/vm_version_x86.hpp            - 10 lines changed: 9 ins; 0 del; 1 mod
> 
> 
> Reproduced the reported issue - Some values not changed with command line flags.
> <jbs> - https://bugs.openjdk.java.net/browse/JDK-8016470
> 
> Checked all the related command line flags, values setting for various targets.
> The proposed fix is to add required FLAG_IS_DEFAULT() checks for related flags 
> before modifying with any default platform dependent values,
> to avoid the overwriting of command line values passed.
> 
> Confirmed changes fix reported issue.
> . e.g. with fix :  $ java -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -XX:AllocateInstancePrefetchLines=6 -XX:AllocatePrefetchDistance=256 -XX:AllocatePrefetchInstr=1
>  -XX:AllocatePrefetchLines=2 -XX:AllocatePrefetchStepSize=32 -XX:AllocatePrefetchStyle=3 -XX:+PrintFlagsFinal -version 2>&1 | grep Allocate
>        intx AllocateInstancePrefetchLines            = 6                                        {product} {command line}
>        intx AllocatePrefetchDistance                 = 256                                      {product} {command line}
>        intx AllocatePrefetchInstr                    = 1                                        {product} {command line}
>        intx AllocatePrefetchLines                    = 2                                        {product} {command line}
>        intx AllocatePrefetchStepSize                 = 32                                       {product} {command line}
>        intx AllocatePrefetchStyle                    = 3                                        {product} {command line}
> 
> 
> Thanks,
> Rahul
>