Require asserts for AD tests using the debug-only flag

[asuhan]

No description provided.

[dan-zheng]

Thanks, nice catch! (If we had CI running tests with no-assertions, I think this error could've been caught earlier.)

[dan-zheng]

@swift-ci Please clean test tensorflow

[bgogul]

Thanks, nice catch! (If we had CI running tests with no-assertions, I think this error could've been caught earlier.)

Do we even need --debug-only=differentiation for the test?

[dan-zheng]

Thanks, nice catch! (If we had CI running tests with no-assertions, I think this error could've been caught earlier.)

Do we even need --debug-only=differentiation for the test?

Sadly, yes we do, for the purpose of checking AD-generated structs and enums.

During one of the recent merges, structs and enums were changed to be implicit (as they should), meaning they no longer show up via any dumping (e.g. -emit-sil). So, I added LLVM_DEBUG print statements to print the structs and enums via -debug-only=differentiation.

We could add a separate -Xllvm flag just for printing the data structures, but I think reusing -debug-only=differentiation is fine. Other SILOptimizer tests also use -debug-only to FileCheck various properties.