[llvm] [LV] Allow partial reductions with an extended bin op (PR #165536)

[Sam Tebbs via llvm-commits]

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@@ -2123,6 +2123,512 @@ for.exit:                        ; preds = %for.body
   ret i32 %result
 }
 
+define i32 @dotp_ext_mul(i64 %n, ptr %a, i8 %b) {
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SamTebbs33 wrote:

I think splitting this up is out of scope for the PR, since it would involve touching other tests that aren't related to this work.

> We probably also do not need to check for all possible combinations for all tests, especially the negative ones.

Are there any specific test functions in here that you think are unnecessary?

https://github.com/llvm/llvm-project/pull/165536