[llvm] [RISCV] Vectorize phi for loop carried @llvm.vp.reduce.* (PR #131974)

[Luke Lau via llvm-commits]

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@@ -42,3 +42,459 @@ vector.body:
 exit:
   ret float %acc
 }
+
+define i32 @vp_reduce_add(ptr %a) {
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lukel97 wrote:

Oh sorry, I meant as in only having two commits, one that adds the tests without the changes in RISCVCodgenPrepare, and another with the changes in RISCVCodegenPrepare that shows the change in the tests, e.g. see https://llvm.org/docs/InstCombineContributorGuide.html#precommit-tests

https://github.com/llvm/llvm-project/pull/131974