[clang] [Clang][LoongArch] Add support for UEFI target (PR #155598)

[Lu Weining via cfe-commits]

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@@ -77,3 +77,9 @@
 // RUN: not %clang_cl --target=x86-unknown-uefi -o %t.o %s 2> %t.err
 // RUN: FileCheck --input-file=%t.err -check-prefixes=CHECK-x86 %s
 // CHECK-x86: error: unknown target triple 'x86-unknown-uefi'{{$}}
+
+// RUN: not %clang --target=loongarch-unknown-uefi -o %t.o %s 2> %t.err
+// RUN: FileCheck --input-file=%t.err -check-prefixes=CHECK-la %s
+// RUN: not %clang_cl --target=loongarch-unknown-uefi -o %t.o %s 2> %t.err
+// RUN: FileCheck --input-file=%t.err -check-prefixes=CHECK-la %s
+// CHECK-la: error: unknown target triple 'loongarch-unknown-uefi'{{$}}
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SixWeining wrote:

I think it's not need to add this `invalid-arch` test.

https://github.com/llvm/llvm-project/pull/155598