[llvm] Handle Call Operand vxi1 in Hexagon Backend (PR #128027)

[Alex Rønne Petersen via llvm-commits]

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@@ -0,0 +1,39 @@
+;RUN: llc -mtriple=hexagon -mattr=+hvxv79,+hvx-length128b < %s -o - | FileCheck %s
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alexrp wrote:

Putting on my Zig hat: Broadly speaking, we rely on LLVM to treat vectors as first class, regardless of what element type or size they have. So we expect them to Just Work when used in calls, for example. My stance is still that an LLVM backend should be able to lower any call involving vectors, even if that means using a bespoke (and possibly unstable) parameter passing convention for the unusual cases that you aren't going to see in e.g. C/C++ ABIs. This seems to be the norm in other backends.

Having said that, even if this PR doesn't address all cases, it still seems like a clear improvement to me. Note, though, that HVX is off by default in the Hexagon backend, so I don't think this PR is sufficient to close #59009 and #118879.

https://github.com/llvm/llvm-project/pull/128027