[llvm] [AArch64][NEON] Lower fixed-width add partial reductions to dot product (PR #107078)

[Paul Walker via llvm-commits]

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@@ -0,0 +1,209 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 5
+; RUN: llc -mtriple aarch64 -mattr=+neon,+dotprod < %s | FileCheck %s
+; RUN: llc -mtriple aarch64 -mattr=+neon < %s | FileCheck %s --check-prefix=CHECK-NODOTPROD
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paulwalker-arm wrote:

By using `--check-prefixes=` you'll only generate a single set of check lines for the common cases (i.e. the negative tests).

For example:
```
--check-prefixes=CHECK,DOT
--check-prefixes=CHECK,NODOT
```

https://github.com/llvm/llvm-project/pull/107078