[llvm] [RISCV] Account for factor in interleave memory op costs (PR #111511)

[Luke Lau via llvm-commits]

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@@ -481,7 +485,7 @@ loop:
   %ext  = zext i8 %l.1 to i32
   %gep.dst = getelementptr i32, ptr %dst, i64 %iv
   store i32 %ext, ptr %gep.dst, align 4
-  %iv.next = add nsw i64 %iv, 4
+  %iv.next = add nsw i64 %iv, 2
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lukel97 wrote:

Since the cost of non-NF2 interleaves has gone up I had to change the stride here so the loop vectorizer still decides to use an interleave group here.

https://github.com/llvm/llvm-project/pull/111511