[llvm] [RISCV][CFI] add function epilogue cfi information (PR #110810)

[Sam Elliott via llvm-commits]

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@@ -56,10 +56,11 @@ define riscv_vector_cc <vscale x 1 x i32> @test_vector_callee_cfi(<vscale x 1 x
 ; OMIT-FP-NEXT:    .cfi_def_cfa sp, 16
 ; OMIT-FP-NEXT:    .cfi_restore v1
 ; OMIT-FP-NEXT:    .cfi_restore v2
+; OMIT-FP-NEXT:    .cfi_restore v3
 ; OMIT-FP-NEXT:    .cfi_restore v4
-; OMIT-FP-NEXT:    .cfi_restore v1
-; OMIT-FP-NEXT:    .cfi_restore v2
-; OMIT-FP-NEXT:    .cfi_restore v4
+; OMIT-FP-NEXT:    .cfi_restore v5
+; OMIT-FP-NEXT:    .cfi_restore v6
+; OMIT-FP-NEXT:    .cfi_restore v7
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lenary wrote:

I'm not very familiar with the V extension, but this looks much better, if `vl2r.v` and `vl4r.v` are going to restore 2 and 4 consecutive v registers respectively.

https://github.com/llvm/llvm-project/pull/110810