[llvm] [RISCV][ISel] Fold trunc (lshr (add (zext X), (zext Y)), 1) -> vaaddu X, Y (PR #76550)

[Luke Lau via llvm-commits]

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@@ -0,0 +1,186 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -mtriple=riscv32 -mattr=+v -verify-machineinstrs < %s | FileCheck %s
+; RUN: llc -mtriple=riscv64 -mattr=+v -verify-machineinstrs < %s | FileCheck %s
+
+
+define <8 x i8> @vaaddu_i8(ptr %x, ptr %y) {
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lukel97 wrote:

Another nit sorry, can we also name the tests in the form:

```llvm
define <8 x i8> @vaaddu_vv_v8i8(<8 x i8> %x, <8 x i8> %y)

define <8 x i8> @vaaddu_vv_nxv8i8(<vscale x 8 x i8> %x, <vscale x 8 x i8> %y)
```

to be consistent with the other tests in the testsuite

https://github.com/llvm/llvm-project/pull/76550