[llvm] [clang] [FuncAttrs] Deduce `noundef` attributes for return values (PR #76553)

[Nikita Popov via cfe-commits]

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@@ -27,7 +27,7 @@
 #endif
 
 // function return types
-// CHECK-LABEL: define dso_local <8 x half> @test_ret_v8f16(
+// CHECK-LABEL: define dso_local noundef <8 x half> @test_ret_v8f16(
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nikic wrote:

Do you know why clang places the noundef on the argument but not the return for these, despite them having the same type?

https://github.com/llvm/llvm-project/pull/76553