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JDK-6239807 : Add check for additional features on x86

Details
Type:
Enhancement
Submit Date:
2005-03-12
Status:
Resolved
Updated Date:
2010-04-03
Project Name:
JDK
Resolved Date:
2005-04-06
Component:
hotspot
OS:
solaris_9
Sub-Component:
compiler
CPU:
sparc
Priority:
P4
Resolution:
Fixed
Affected Versions:
6
Fixed Versions:

Related Reports

Sub Tasks

Description
Need check for AMD features on x86: 3dnow, prefetchw.
Also add check for SSE3.


###@###.### 2005-03-12 00:40:11 GMT

                                    

Comments
EVALUATION

Need checks for AMD features on x86 (32-bits): 3dnow, prefetchw.
Check SSE3 for future use.

###@###.### 2005-04-01 00:06:16 GMT
                                     
2005-04-01
SUGGESTED FIX

Webrev:                 http://analemma.sfbay.sun.com/net/prt-archiver.sfbay/data/archived_workspaces/main/c2_baseline/2005/20050329164723.kvn.6239807/workspace/webrevs/webrev-2005.03.29/index.html

Check the result of CPUID instruction for AMD features
(the code was taken from the amd64 port).

Use this information to generate correspondent most efficient
heap allocation prefetch instruction on x86:
Pentium 3 - prefetcht2  128
Pentium 4 - prefetchnta 512
Athlon    - prefetchw   128
Opteron   - prefetchw   386

And don't generate any prefetching instructions when SSE or 3DNow
are not supported (after the fix for 6229114 we are generating
CMP EAX,(mem+dist) which could reference outside a heap).

Add check for SSE3 (change 'UseSSE==2' to 'UseSSE>=2').
It is only check - the preparation for the future use of
SSE3 instructions.

Note: I also did the experiment with GC prefetching but didn't
see improvement since you have to generate the sse check
in addition to a prefetch instruction.


###@###.### 2005-04-01 00:06:16 GMT
                                     
2005-04-01



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