[llvm] [RISCV] Add optimization for memset inline (PR #146673)

[Pengcheng Wang via llvm-commits]

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@@ -682,18 +654,22 @@ define void @aligned_bzero_64(ptr %a) nounwind {
 define void @aligned_bzero_66(ptr %a) nounwind {
 ; RV32-BOTH-LABEL: aligned_bzero_66:
 ; RV32-BOTH:       # %bb.0:
-; RV32-BOTH-NEXT:    sh zero, 64(a0)
-; RV32-BOTH-NEXT:    vsetivli zero, 8, e64, m4, ta, ma
+; RV32-BOTH-NEXT:    li a1, 128
+; RV32-BOTH-NEXT:    vsetvli zero, a1, e8, m8, ta, ma
 ; RV32-BOTH-NEXT:    vmv.v.i v8, 0
-; RV32-BOTH-NEXT:    vse64.v v8, (a0)
+; RV32-BOTH-NEXT:    li a1, 66
+; RV32-BOTH-NEXT:    vsetvli zero, a1, e8, m8, ta, ma
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wangpc-pp wrote:

This should be a place that VLOptimizer can step in?

https://github.com/llvm/llvm-project/pull/146673