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<div class="moz-cite-prefix">On 10/18/12 5:32 AM, Nadav Rotem wrote:<br>
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<div>On Oct 17, 2012, at 6:24 PM, Hal Finkel <<a
moz-do-not-send="true" href="mailto:hfinkel@anl.gov">hfinkel@anl.gov</a>>
wrote:</div>
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float: none; ">he current pass handles only fixed trip-count
(single-exit) loops without inter-iteration dependencies,
correct? For this class of loops, I believe that what I
proposed is correct. Maybe I'm thinking about this
incorrectly, can you please provide a counterexample?</span><br
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<div>Yes. If there are no cross-iteration dependencies then x
equals to the last SIMD lane. I missed the part which said that
there are no cross-iteration deps. </div>
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I agree. Nadav's comment is correct only if the value forms a
cross-iteration dependency (read: it is live on the back edge / it
is the operand of a phi in the loop header).<br>
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