RFR : fix Assembler::prefix_and_encode for x86

[Igor Ignatyev]

Hi Doug,

03eda0a202e9[1] was integrated into Graal only, so this fix isn't needed 
for upstream.

-Igor

[1]
> changeset:   16064:03eda0a202e9
> user:        Christian Wimmer <christian.wimmer at oracle.com>
> date:        Fri Jun 06 11:06:42 2014 -0700
> files:       graal/com.oracle.graal.asm.amd64/src/com/oracle/graal/asm/amd64/AMD64Assembler.java src/cpu/x86/vm/assembler_x86.cpp src/cpu/x86/vm/assembler_x86.hpp
> description:
> Better fix for prefix byte for AMD64 byte instruction

On 01/13/2015 01:03 PM, Doug Simon wrote:
> Are you sure this fix should be made in the Graal code base? Seems like an upstream patch to me.
>
>> On Jan 13, 2015, at 10:58 AM, Igor Ignatyev <igor.ignatyev at oracle.com> wrote:
>>
>> Hi all,
>>
>> please review the fix for Assembler::prefix_and_encode method for 32bit:
>> 16064:03eda0a202e9 changed signature of this method and implementation for 64bit (in assembler_x86.cpp), however 32bit inline version wasn't changed.
>>
>> http://cr.openjdk.java.net/~iignatyev/graal/i586_prefix_and_encode/webrev.00/
>>
>> --
>> Thanks,
>> Igor
>