[llvm] [RISCV]Add support for resolving encoding conflicts among vendor specific CSRs (PR #96174)

[Jessica Clarke via llvm-commits]

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@@ -0,0 +1,109 @@
+// RUN: llvm-tblgen -gen-searchable-tables -I %p/../../include %s | FileCheck %s
+
+include "llvm/TableGen/SearchableTable.td"
+
+class SysReg<string name, bits<12> op> {
+  string Name = name;
+  bits<12> Encoding = op;
+  code FeaturesRequired = [{ {} }];
+}
+
+def List1 : GenericTable {
+  let FilterClass = "SysReg";
+  let Fields = [
+     "Name", "Encoding", "FeaturesRequired",
+  ];
+
+  let PrimaryKey = [ "Encoding" ];
+  let PrimaryKeyName = "lookupSysRegByEncoding";
+  let PrimaryKeyReturnRange = true;
+}
+
+
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jrtc27 wrote:

```suggestion

```

https://github.com/llvm/llvm-project/pull/96174