[llvm] [clang] [flang] [flang] add fveclib flag (PR #71734)

[Tom Eccles via cfe-commits]

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@@ -0,0 +1,13 @@
+! test that -fveclib= is passed to the backend
+! -target aarch64 so that ArmPL is available
+! RUN: %flang -S -target aarch64-unknown-linux-gnu -mcpu=neoverse-v1 -Ofast -fveclib=ArmPL -o - %s | FileCheck %s
+
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tblah wrote:

-fveclib should work on all targets which clang supports (I have only tested aarch64). ArmPL is only available on aarch64 (and this is enforced in the compiler driver) so I added the target here. I used ArmPL for the test because I know what the right result looks like for ArmPL, but not for other libraries.

https://github.com/llvm/llvm-project/pull/71734