[clang] [Clang][RISCV] Support -fcf-protection=return for RISC-V (PR #112477)

[Jesse Huang via cfe-commits]

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@@ -899,6 +899,10 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
   if (CodeGenOpts.PointerAuth.IndirectGotos)
     Fn->addFnAttr("ptrauth-indirect-gotos");
 
+  // Add return control flow integrity attributes.
+  if (CodeGenOpts.CFProtectionReturn)
+    Fn->addFnAttr("hw-shadow-stack");
+
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jaidTw wrote:

Yeah nice catch, it definitely needs to check the arch

https://github.com/llvm/llvm-project/pull/112477