[llvm] [ELF] Correctly set the `nvptx` triple from `makeTriple()` (PR #76970)

[Joseph Huber via llvm-commits]

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@@ -1349,6 +1349,13 @@ template <class ELFT> Triple::ArchType ELFObjectFile<ELFT>::getArch() const {
     return Triple::UnknownArch;
   }
 
+  case ELF::EM_CUDA: {
+    if (EF.getHeader().e_ident[ELF::EI_CLASS] == ELF::ELFCLASS32)
+      return Triple::nvptx;
+    else
+      return Triple::nvptx64;
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jhuber6 wrote:

There weren't any existing tests for any of this code, so I just punted it until the second patch. Thanks, I'll do the NFC.

https://github.com/llvm/llvm-project/pull/76970