[clang] [llvm] [Darwin][Clang][PGO] Pass CSPGO related flags to ld when using libLTO.dylib (PR #195020)

[Henry Jiang via cfe-commits]

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@@ -0,0 +1,21 @@
+; REQUIRES: aarch64-registered-target
+;
+; RUN: llvm-profdata merge %S/Inputs/cspgo-noncs.proftext -o %t.profdata
+; RUN: opt -module-summary %s -o %t.o
+; RUN: llvm-lto -thinlto-action=optimize \
+; RUN:   -cs-profile-generate -cs-profile-path=%t.profdata \
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mustartt wrote:

Thanks for taking a look.

> Is there a way to write a test to make sure the generated path is correctly applied?

On the `-cs-profile-generate`, there really isn't a good way to test that the path is applied correctly. But we can verify that `-cs-profile-path` is correctly forwarded implicitly when using `-fcs-profile-use`. So I think testing it here should be sufficient for this use case.

> Also it will be good to have a test for profile-use as well.

Added a `-fcs-profile-use` test case for thinlto. 

https://github.com/llvm/llvm-project/pull/195020