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<div class="moz-cite-prefix">On 08/18/2016 10:24 AM, Xiaochu Liu via
llvm-dev wrote:<br>
</div>
<blockquote
cite="mid:CAAYJeWZSfF-vWBWs+LgD28F-_i65Zgfj9Mmuze=gUoeQp73ToQ@mail.gmail.com"
type="cite">
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<p dir="ltr">Hi there,</p>
<p dir="ltr">I'm trying to map extract_vector_elt use the
following pattern in tbl file.</p>
<p dir="ltr">Def : Pat <(i64 (extractelt v2i32:$src, 0)), (i64
(SRLIMM GPR:$src, 32))>;</p>
<p dir="ltr">But the tblgen shows :</p>
<p dir="ltr">Type inference contradiction found , forcing v2i32 to
have a vector element of type i64</p>
<p dir="ltr">But the manual says this instruction allows return
type to be larger than element type.</p>
<p dir="ltr">Anyone can show me any pointers ? </p>
<p dir="ltr">Thanks,<br>
Xiaochu</p>
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<p><br>
</p>
<p>I think this is just intended as a quirk for some weird targets
that have a legal vector type, but the scalar type itself is not
legal, so it requires an implicit extension when extracting it. I
don't think it's intended as something you can arbitrarily do for
any vector type, and I wouldn't recommend trying to use it if you
don't have to. This probably requires custom selector code<br>
</p>
<p>-Matt<br>
</p>
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