[llvm] [memprof] Add YAML read/write support to llvm-profdata (PR #118915)

[Kazu Hirata via llvm-commits]

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@@ -0,0 +1,8 @@
+; REQUIRES: x86_64-linux
+; RUN: split-file %s %t
+; RUN: not llvm-profdata merge %t/memprof-invalid.yaml -o %t/memprof-invalid.indexed
+
+; Verify that the invalid YAML input results in an error.
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kazutakahirata wrote:

Yes, we do get meaningful errors.  Let's say we've misspelled `HeapProfileRecords:` as `BeepProfileRecords:`.  Then we get:

```
$ ./path/to/bin/llvm-profdata merge --memprof-version=3 --output=/tmp/junk.memprof  MemProf.yaml
YAML:2:1: error: missing required key 'HeapProfileRecords'
BeepProfileRecords:
^
warning: MemProf.yaml: The profile is empty.
error: no profile can be merged
```

Now, I must admit that I am not wiring the YAML error to a nonzero exit code.  Instead, I'm returning a nonzero exit code on the empty profile.  I'm planning to fix this with a follow-up patch.


https://github.com/llvm/llvm-project/pull/118915