JDK-6873777 : FPU control word optimization still performed with SSE
  • Type: Bug
  • Component: hotspot
  • Sub-Component: compiler
  • Affected Version: hs17
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • OS: solaris_9
  • CPU: x86
  • Submitted: 2009-08-19
  • Updated: 2010-04-02
  • Resolved: 2009-09-16
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JDK 6 JDK 7 Other
6u21Fixed 7Fixed hs17Fixed
Description
While looking at generated code for another reason, I noticed that C2 tries to do the 24 fpu optimization even when SSE is being used for floating point.  This creates at least a little overhead from the extra fldcw calls and is certainly useless.

Comments
EVALUATION http://hg.openjdk.java.net/jdk7/hotspot-comp/hotspot/rev/cd18bd5e667c
20-08-2009