[llvm] [CGData] llvm-cgdata (PR #89884)

[Ellis Hoag via llvm-commits]

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@@ -0,0 +1,32 @@
+# Test for empty cgdata file, which is invalid.
+RUN: touch %t_emptyfile.cgtext
+RUN: not llvm-cgdata dump %t_emptyfile.cgtext -text -o - 2>&1 | FileCheck %s --check-prefix ERROR
+ERROR: {{.}}emptyfile.cgtext: empty codegen data
+
+# Test for empty header in the text format. It can be converted to a valid binary file.
+RUN: printf '#' > %t_emptyheader.cgtext
+RUN: llvm-cgdata dump %t_emptyheader.cgtext -binary -o %t_emptyheader.cgdata
+
+# Without any cgdata other than the header, no data shows by default.
+RUN: llvm-cgdata show %t_emptyheader.cgdata | FileCheck %s --allow-empty --check-prefix EMPTY
+EMPTY-NOT: any
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ellishg wrote:

I think this will detect if the output is empty. I'm not sure if there is a better way.
```suggestion
RUN: llvm-cgdata show %t_emptyheader.cgdata | count 0
```

https://github.com/llvm/llvm-project/pull/89884