[llvm] [DXIL] Add DXIL SubArch to correspond to version number (PR #89125)

[Chris B via llvm-commits]

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@@ -165,6 +165,17 @@ class Triple {
     SPIRVSubArch_v14,
     SPIRVSubArch_v15,
     SPIRVSubArch_v16,
+
+    // DXIL sub-arch corresponds to its version.
+    DXILSubArch_v10,
+    DXILSubArch_v11,
+    DXILSubArch_v12,
+    DXILSubArch_v13,
+    DXILSubArch_v14,
+    DXILSubArch_v15,
+    DXILSubArch_v16,
+    DXILSubArch_v17,
+    DXILSubArch_v18,
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llvm-beanz wrote:

This is going to get real awkward if we hit v 1.10... maybe we should separate the major and minor versions with `_`.

https://github.com/llvm/llvm-project/pull/89125