[PATCH] [PowerPC] Implement miscellaneous vector logical operations introduced in POWER8

Kit Barton kbarton at ca.ibm.com
Fri Feb 6 09:25:50 PST 2015

How is the following:

// FIXME: Use AddedComplexity > 400 to ensure these patterns match before the
//        VSX equivalents. We need to fix this up at some point. Two possible
//        solutions for this problem:
//        1. Disable Altivec patterns that compete with VSX patterns using the
//           !HasVSX predicate. This essentially favours VSX over Altivec, in
//           hopes of reducing register pressure (larger register set using VSX
//           instructions then VMX instructions)
//        2. Employ a more disciplined use of AddedComplexity, which would provide
//           more fine-grained control then option 1. This would be beneficial
//           if we find situations where Altivec is really preferred over VSX.



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