Hi,

* continued working on cost model tuning. I don't see much difference
running EEMBC DenBench with and without vectorization enabled (and,
therefore, also with and without cost model).
Also, I have to say, that the results are not stable and I sometimes
get 10% difference just running the same executable two times in a
row.

* the only benchmark I see consistent degradation 5% with
vectorization is DenBench aes, both with GCC trunk and gcc-linaro 4.5.
I found one of the responsible loops, if it is not vectorized I see
only 1.8% degradation. The problem there is that the loop bound is
unknown at compile time, so the vectorizer attempts to vectorize the
loop using runtime guards to verify that there are enough iterations
to vectorize. The actual number of iterations is 4, so the scalar
version of the loop is chosen at the run time, but I guess the guards
cause the degradation. I'll continue looking into this next week.

* prepared the conditional-store-sink patch (one of the patches that
helps to vectorize Telecom Viterbi) for submission to gcc-patches.

Ira

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