[PATCH] D104451: [GlobalISel] NFC: Change LLT::vector to take ElementCount.

[Sander de Smalen via Phabricator via llvm-commits]

sdesmalen added inline comments.


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Comment at: llvm/include/llvm/Support/LowLevelTypeImpl.h:100
   static LLT scalarOrVector(uint16_t NumElements, LLT ScalarTy) {
-    return NumElements == 1 ? ScalarTy : LLT::vector(NumElements, ScalarTy);
+    // FIXME: Migrate interface to use ElementCount
+    return NumElements == 1 ? ScalarTy
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arsenm wrote:
> Is there actually a context where you would use this which would need a scalable vector?
The context would be where the algorithm that uses `scalarOrVector` is agnostic of whether the type is fixed or scalable and just passes an `ElementCount`.
As an example: `LLT::divide(int Factor)` would return `v2i64` for `v4i64.divide(2)`, `nxv2i64` for `nxv4i64.divide(2)`, but `i64` for `v2i64.divide(2)`. And instead of having to write if conditional code, it can work on ElementCount directly (see its implementation in D104452)


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  https://reviews.llvm.org/D104451/new/

https://reviews.llvm.org/D104451