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

[Jesse Huang via cfe-commits]

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@@ -0,0 +1,9 @@
+// RUN: %clang_cc1 -triple riscv64-linux-unknown -target-feature +zimop -emit-llvm -o - %s -fcf-protection=return | FileCheck -check-prefix=NOTIGNORELISTED %s
+// RUN: %clang_cc1 -triple riscv64-linux-unknown -target-feature +zimop -emit-llvm -o - %s | FileCheck -check-prefix=IGNORELISTED %s
+
+int foo(int *a) { return *a; }
+
+// CHECK: define i32 @foo(ptr %a)
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jaidTw wrote:

It's surely not used so I've removed it
(This test is modified from `clang/test/CodeGen/shadowcallstack-attr.c`, so as the line, but seems like it isn't used in the original file either)

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