[PATCH] D146988: [CodeGen] Enable processing of interconnected complex number operations

[Igor Kirillov via Phabricator via llvm-commits]

igor.kirillov added inline comments.


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Comment at: llvm/test/CodeGen/AArch64/complex-deinterleaving-multiuses.ll:93
+;   *p2 = (a * b) * c;
+;   return d * c
+define <4 x float> @monster(<4 x float> %a, <4 x float> %b, <4 x float> %c, <4 x float> %d, ptr %p1, ptr %p2) {
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NickGuy wrote:
> dmgreen wrote:
> > It is not obvious to me why d * c should prevent the rest of the tree transforming. Can you precommit the tests to show the differences in the review?
> I'm not sure it's the `d * c` that's preventing it, so much as the store to %p1 (It doesn't reinterleave, so the store is deemed "outside the graph").
> Though I agree, pre-commits would be useful to see the difference in the other cases
The idea is that any external use of complex computation chain prevents deinterleaving. And if one chain stops to be deinterleaved it might effect another chain, which is shown in this test. *p1 prevent for a*b to be deinterleaved, which in its turn prevents (a * b * c)  to be deinterleaved and that in its turn spoils d*c expression. As result nothing is deinterleaved.

At least that's what I thought before pre-commiting this tests where pre-patch code decided to deinterleaved d * c operation - https://reviews.llvm.org/D147659. Now, I have a question. If shufflevector is used outside, should we still deinterleave code?


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CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D146988/new/

https://reviews.llvm.org/D146988