[clang] [flang] [llvm] [flang] Add runtime trampoline pool for W^X compliance (PR #183108)

[Tarun Prabhu via cfe-commits]

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@@ -0,0 +1,99 @@
+! RUN: %flang -fsafe-trampoline -emit-llvm -S -o - %s | FileCheck %s
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tarunprabhu wrote:

Most tests in `flang/test/Lower` use `%flang_fc1`. We should probably stick to that convention.

```suggestion
! RUN: %flang_fc1 -fsafe-trampoline -emit-llvm -o - %s | FileCheck %s
```

https://github.com/llvm/llvm-project/pull/183108