[clang] [llvm] [DirectX][DXIL] Set DXIL Version in DXIL target triple based on shader model version (PR #90809)

[S. Bharadwaj Yadavalli via cfe-commits]

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@@ -115,6 +115,30 @@ StringRef Triple::getArchName(ArchType Kind, SubArchType SubArch) {
     if (SubArch == AArch64SubArch_arm64e)
       return "arm64e";
     break;
+  case Triple::dxil:
+    switch (SubArch) {
+    case Triple::NoSubArch:
+    case Triple::DXILSubArch_v1_0:
+      return "dxilv1.0";
+    case Triple::DXILSubArch_v1_1:
+      return "dxilv1.1";
+    case Triple::DXILSubArch_v1_2:
+      return "dxilv1.2";
+    case Triple::DXILSubArch_v1_3:
+      return "dxilv1.3";
+    case Triple::DXILSubArch_v1_4:
+      return "dxilv1.4";
+    case Triple::DXILSubArch_v1_5:
+      return "dxilv1.5";
+    case Triple::DXILSubArch_v1_6:
+      return "dxilv1.6";
+    case Triple::DXILSubArch_v1_7:
+      return "dxilv1.7";
+    case Triple::DXILSubArch_v1_8:
+      return "dxilv1.8";
+    default:
+      return "";
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bharadwajy wrote:

> I would argue that returning an empty string here is just as inconsistent as erroring out/crashing. We should probably just do (2) even though it's obviously ridiculous, since for other architectures if you provide an invalid subarch they are indeed just as ridiculous.

OK. Pushed a change that uses option (2).

https://github.com/llvm/llvm-project/pull/90809