On Sat, 26 Oct 2024 02:34:44 GMT, Quan Anh Mai <qa...@openjdk.org> wrote:
>>> By allowing lowering to look through VectorReinterpret and break the >>> invariant of Extract nodes that the element types of their inputs and >>> outputs must be the same, we can gvn v1 and v, v2 and v0. >> >> I'd warn against breaking existing IR invariants. As an example, precise >> type information is important to properly match generic ideal vector nodes. > > I believe the matcher only needs the exact type of the node but not its > inputs. E.g. it should not be an issue if we `AddVB` a `vector<int,8>` and a > `vector<long,2>` into a `vector<byte,16>`. Generic vector operand resolution cocretizes generic operands based on type agnostic node size, its a post matcher pass, and its job is to replace generic MachOper operand nodes with cocrete ones (vec[SDXYZ]) which holds precise register mask needed by register allocator. ------------- PR Review Comment: https://git.openjdk.org/jdk/pull/21599#discussion_r1817960219
