JDK-6239807 : Add check for additional features on x86
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: 6
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • OS: solaris_9
  • CPU: sparc
  • Submitted: 2005-03-12
  • Updated: 2010-04-03
  • Resolved: 2005-04-06
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JDK 6
6 b31Fixed
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