[clang] [lanai] Add back the ability to set the memory model with --mcmodel. (PR #150575)

[Jacques Pienaar via cfe-commits]

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@@ -3125,6 +3125,8 @@ void tools::addMCModel(const Driver &D, const llvm::opt::ArgList &Args,
       else if (CM == "medany")
         CM = "large";
       Ok = CM == "small" || CM == "medium" || CM == "large";
+    } else if (Triple.getArch() == llvm::Triple::lanai) {
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jpienaar wrote:

I was wondering if there is an ordering here, but I can't really see one, so at end SG,

https://github.com/llvm/llvm-project/pull/150575