[clang] [llvm] [RISCV] Support resumable non-maskable interrupt handlers (PR #148134)

[Sam Elliott via llvm-commits]

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@@ -75,6 +75,8 @@ def riscv_sret_glue : RVSDNode<"SRET_GLUE", SDTNone,
                                [SDNPHasChain, SDNPOptInGlue]>;
 def riscv_mret_glue : RVSDNode<"MRET_GLUE", SDTNone,
                                [SDNPHasChain, SDNPOptInGlue]>;
+def riscv_mnret_glue : RVSDNode<"MNRET_GLUE", SDTNone,
+                               [SDNPHasChain, SDNPOptInGlue]>;
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lenary wrote:

```suggestion
def riscv_mnret_glue : RVSDNode<"MNRET_GLUE", SDTNone,
                                [SDNPHasChain, SDNPOptInGlue]>;
```

https://github.com/llvm/llvm-project/pull/148134