[clang] [CIR] Add support for function linkage and visibility (PR #145600)

[Sirui Mu via cfe-commits]

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@@ -1534,6 +1567,27 @@ void CIRGenModule::setGVPropertiesAux(mlir::Operation *op,
   assert(!cir::MissingFeatures::opGlobalPartition());
 }
 
+void CIRGenModule::setFunctionAttributes(GlobalDecl globalDecl,
+                                         cir::FuncOp func,
+                                         bool isIncompleteFunction,
+                                         bool isThunk) {
+  // NOTE(cir): Original CodeGen checks if this is an intrinsic. In CIR we
+  // represent them in dedicated ops. The correct attributes are ensured during
+  // translation to LLVM. Thus, we don't need to check for them here.
+
+  assert(!cir::MissingFeatures::setFunctionAttributes());
+  assert(!cir::MissingFeatures::setTargetAttributes());
+
+  // TODO(cir): This needs a lot of work to better match CodeGen. That
+  // ultimately ends up in setGlobalVisibility, which already has the linkage of
+  // the LLVM GV (corresponding to our FuncOp) computed, so it doesn't have to
+  // recompute it here. This is a minimal fix for now.
+  if (!isLocalLinkage(getFunctionLinkage(globalDecl))) {
+    const auto *decl = globalDecl.getDecl();
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Lancern wrote:

Use explicit type here

https://github.com/llvm/llvm-project/pull/145600