[llvm] [Instrumentation] Mark instrumented calls as implicit (PR #106447)

[Jeremy Morse via llvm-commits]

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@@ -16,7 +16,7 @@
 
 ; Test that __sanitizer_cov_trace_pc_guard call has !dbg pointing to the opening { of A::f().
 ; CHECK: call void @__sanitizer_cov_trace_pc_guard(ptr{{.*}}) #{{.*}}, !dbg [[A:!.*]]
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jmorse wrote:

This comment will want updating as it's now not true I guess; it's unclear to me whether this indicates there are expectations that the coverage call gets a "real" source location?

https://github.com/llvm/llvm-project/pull/106447