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References: <bug-41881-3264@http.gcc.gnu.org/bugzilla/>
Subject: [Bug tree-optimization/41881] [4.5/4.6 regression] Complete unrolling (inner) versus vectorization of reduction
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From: "irar at il dot ibm dot com" <gcc-bugzilla@gcc.gnu.org>
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------- Comment #7 from irar at il dot ibm dot com  2010-08-11 10:24 -------
(In reply to comment #6)
> I think that SLP doesn't handle reduction.
> 

Not all kinds of reduction. We handle

#a1 = phi <a0, a2>
#b1 = phi <b0, b2>
...
a2 = a1 + x
b2 = b1 + y

Here we also have:
#a1 = phi <a0, a9>
...
a2 = a1 + x
...
a3 = a2 + y
...

a9 = a8 + z


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41881