[clang] [CIR] Upstream support for calling functions via member expressions (PR #164518)

[Andy Kaylor via cfe-commits]

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@@ -1820,10 +1820,10 @@ CIRGenCallee CIRGenFunction::emitCallee(const clang::Expr *e) {
     // Resolve direct calls.
     const auto *funcDecl = cast<FunctionDecl>(declRef->getDecl());
     return emitDirectCallee(funcDecl);
-  } else if (isa<MemberExpr>(e)) {
-    cgm.errorNYI(e->getSourceRange(),
-                 "emitCallee: call to member function is NYI");
-    return {};
+  } else if (auto me = dyn_cast<MemberExpr>(e)) {
+    const auto *fd = cast<FunctionDecl>(me->getMemberDecl());
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andykaylor wrote:

I noticed that, and the incubator does the same thing, but if the dyn_cast returns null, both just fall through to the indirect reference handling, and I couldn't find a case where that actually happens so I wasn't confident that it was the right thing to do. We made the same change (`if (dyn_cast...)` -> `cast`) just above this in the DeclRefExpr handling.

https://github.com/llvm/llvm-project/pull/164518