+ StringRef HostTripleString(LLVM_HOSTTRIPLE);
+ std::pair<StringRef, StringRef> ArchSplit = HostTripleString.split('-');
+
+ // Normalize the arch, since the host triple may not actually match the host.
+ std::string Arch = ArchSplit.first;
+
+ // It would be nice to do this in terms of llvm::Triple, but that is in
+ // Support which is layered above us.
+#if defined(__x86_64__)
+ Arch = "x86_64";
+#elif defined(__i386__)
+ Arch = "i386";
+#elif defined(__ppc64__)
+ Arch = "powerpc64";
+#elif defined(__ppc__)
+ Arch = "powerpc";
+#elif defined(__arm__)
+
+ // FIXME: We need to pick the right ARM triple (which involves querying the
+ // chip). However, for now this is most important for LLVM arch selection, so
+ // we only need to make sure to distinguish ARM and Thumb.
+# if defined(__thumb__)
+ Arch = "thumb";
+# else
+ Arch = "arm";
+# endif
+
+#else
+
+ // FIXME: When enough auto-detection is in place, this should just
+ // #error. Then at least the arch selection is done, and we only need the OS
+ // etc selection to kill off the use of LLVM_HOSTTRIPLE.
+
+#endif
+
+ std::string Triple(Arch);
+ Triple += '-';
+ Triple += ArchSplit.second;