[clang] [clang] Add managarm support (PR #139271)

[Fangrui Song via cfe-commits]

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@@ -228,6 +228,8 @@ static const char *getLDMOption(const llvm::Triple &T, const ArgList &Args) {
       return "elf_iamcu";
     return "elf_i386";
   case llvm::Triple::aarch64:
+    if (T.isOSManagarm())
+      return "aarch64managarm";
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MaskRay wrote:

Is this tested?

https://github.com/llvm/llvm-project/pull/139271