Is i686 the minimum required for HotSpot on x86?

[Christian Thalinger]

On Mar 30, 2011, at 12:44 AM, Dr Andrew John Hughes wrote:
> On 17:31 Tue 29 Mar     , Christian Thalinger wrote:
>> On Mar 29, 2011, at 4:35 PM, Christian Thalinger wrote:
>>> On Mar 29, 2011, at 4:26 PM, Dr Andrew John Hughes wrote:
>>>> We've just had a bug report for IcedTea which suggests that
>>>> HotSpot fails on any x86 platform below i686.
>>>> 
>>>> The report is:
>>>> 
>>>> http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=682
>>>> 
>>>> and shows a failure caused by an attempt by the JIT to emit
>>>> an instruction which isn't present on i586.
>>>> 
>>>> Does HotSpot require i686 as a minimum? Or is there something
>>>> else at fault here?
>>> 
>>> There is a switch -XX:+Use486InstrsOnly but I have an open bug for that one:
>>> 
>>> 6808665: Use486InstrsOnly aborts 32-bit VM
>> 
>> Looking a little closer this could actually be my fault.  I added unguarded cmov instructions to C1 with:
>> 
>> 6919934: JSR 292 needs to support x86 C1
>> 
>> http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/3cf667df43ef
>> 
>> And that was delivered in HS18b01.  I will fix that.
>> 
>> -- Christian
> 
> Ah thanks for finding the issue!  I await the fix.

7032388: guarantee(VM_Version::supports_cmov()) failed: illegal instruction on i586 after 6919934

-- Christian