[llvm] [RISC-V][GISEL] Select G_BITCAST for scalable vectors (PR #101486)

[Michael Maitland via llvm-commits]

michaelmaitland wrote:

> Is there a corresponding `PseudosV*` during instruction selection for load/storing a scalable vector of pointers?

It may be useful to look at RISCVDAGToDAGISel::Select for ISD::LOAD to see what is done there.

Also in RISCVInstrInfoVSDPatterns.td there are some patterns for load/store.

https://github.com/riscv/riscv-v-spec/blob/master/v-spec.adoc#sec-vector-memory might give you a better idea of what kind of vector loads we have. The goal is to pick the best kind of RVV load for a LLVM load instruciton.

https://github.com/llvm/llvm-project/pull/101486