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Sounds very reasonable to me.</div>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" color="#000000" style="font-size:11pt"><b>From:</b> llvm-dev <llvm-dev-bounces@lists.llvm.org> on behalf of Bardia Mahjour via llvm-dev <llvm-dev@lists.llvm.org><br>
<b>Sent:</b> 13 April 2021 22:11<br>
<b>To:</b> llvm-dev@lists.llvm.org <llvm-dev@lists.llvm.org><br>
<b>Subject:</b> [llvm-dev] Should `llvm.loop.unroll.disable` disable interleaving?</font>
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<p><font size="2">Hi,</font><br>
<br>
<font size="2">Currently the `#pragma clang loop unroll(disable)` directive has no impact on loop vectorizer's decision to interleave or not. I think it would make sense to avoid interleaving when the user specifically asked for no unrolling. I'm just wondering
what people think about having `#pragma clang loop unroll(disable)` or `#pragma clang loop unroll_count(1)` imply `#pragma clang loop interleave(disable)`?</font><br>
<br>
<font size="2">> cat tmp.c</font><br>
<font size="2">void foo(int n, int * A)</font><br>
<font size="2">{</font><br>
<font size="2">#pragma clang loop unroll(disable)</font><br>
<font size="2">for (int i = 0; i < n; i++)</font><br>
<font size="2">A[i] = i;</font><br>
<font size="2">}</font><br>
<font size="2">> clang -O3 tmp.c -S -emit-llvm -mllvm -debug-only=loop-vectorize 2>&1 | grep -i interleave</font><br>
<font size="2">LV: Interleave Count is 12</font><br>
<br>
<br>
<font size="2">Bardia Mahjour<br>
Compiler Optimizations<br>
IBM Toronto Software Lab<br>
</font><br>
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