[clang] [clang][X86] Support __attribute__((model("small"/"large"))) (PR #124834)

[Arthur Eubanks via cfe-commits]

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@@ -2949,15 +2950,34 @@ static void handleSectionAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   }
 }
 
+static bool isValidCodeModelAttr(Sema &S, StringRef Str) {
+  if (S.Context.getTargetInfo().getTriple().isLoongArch()) {
+    return Str == "normal" || Str == "medium" || Str == "extreme";
+  } else {
+    assert(S.Context.getTargetInfo().getTriple().getArch() ==
+               llvm::Triple::x86_64 &&
+           "only loongarch/x86-64 supported");
+    return Str == "small" || Str == "large";
+  }
+}
+
 static void handleCodeModelAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   StringRef Str;
   SourceLocation LiteralLoc;
   // Check that it is a string.
   if (!S.checkStringLiteralArgumentAttr(AL, 0, Str, &LiteralLoc))
     return;
 
+  // Ignore the attribute for GPU device compiles since it only applies to host
+  // globals.
+  if (S.Context.getTargetInfo().getTriple().isNVPTX() ||
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aeubanks wrote:

now we warn if both the current target and `getAuxTriple()` don't support the attribute. however, if we're a pure GPU compile with no `getAuxTriple()`, we silently ignore the attribute since we don't know what the host could be. does this work?

https://github.com/llvm/llvm-project/pull/124834