[llvm] [RISCV] Propagate SDNode flags when combining `(fmul (fneg X), ...)` (PR #169460)

[Luke Lau via llvm-commits]

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@@ -0,0 +1,56 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=riscv64 -mattr='+d,+m' < %s | FileCheck %s
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lukel97 wrote:

Nit are the quotes needed?

```suggestion
; RUN: llc -mtriple=riscv64 -mattr=+d,+m < %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/169460