How to test shared_module?

[chriselrod]

I have a project that builds a shared module:

my_shared_module = shared_module(...)

I would like to test it via running an executable that supports loading modules

FILE *fopt = popen("opt -load-pass-plugin=path/to/my_shared_module.so moreargs path/to/file.ll", "r")

and then compare the results with some expected results:

FILE *ftxt = fopen("path/to/cmpfile.txt", "r")

However, I have two problems here:

1. I do not know how to declare my_shared_module.so as a dependency of the test. It is not a shared library, but a shared module loaded by the executable.
2. I do not know how to set the relative paths correctly so that this works on CI.

Or, is there a better approach?

[chriselrod]

Perhaps I can solve the path via defining a macro to be meson.source_root()?

[eli-schwartz]

1. I do not know how to declare my_shared_module.so as a dependency of the test. It is not a shared library, but a shared module loaded by the executable.

test('name', exe, ..., depends: [my_shared_module])

2. I do not know how to set the relative paths correctly so that this works on CI.

How are you running it? If you pass a built target as part of the args: kwarg, Meson will guarantee the path resolves correctly to the built object.

There's also my_shared_module.full_path() to yield a string. This may be necessary if it must be --flag=path/to/module instead of --flag path/to/module. But in that case you need depends: as meson cannot figure out dependencies automatically from a string.

[chriselrod]

Thanks,

test('name', exe, ..., depends: [my_shared_module])

works. Running meson test now causes my_shared_module to build, and it also recompiles when edited and rerunning meson test.

I'll try passing paths now.

How are you running it?

I was simple running meson test.

If you pass a built target as part of the args: kwarg, Meson will guarantee the path resolves correctly to the built object.

This will pass command line args?
I was currently using gtest_main, so didn't have a manually written main function.
But I don't really need gtest for this.

There's also my_shared_module.full_path() to yield a string. This may be necessary if it must be --flag=path/to/module instead of --flag path/to/module. But in that case you need depends: as meson cannot figure out dependencies automatically from a string.

I need paths to:

1. the shared module, which is loaded by the executable.
2. a file that is passed to the executable as an argument.
3. an output file I can compare the executable's output to.

I'm going to be using depends:, of course, but I figure my_shared_module.full_path() is what I'd want for 1., and then meson.source_root() can be used for 2. and 3..

[eli-schwartz]

For 2, you probably want to pass files('foo.txt') as an argument.

For 3, probably the same (although it wasn't clear from your wording whether it is a custom_target build output).

[chriselrod]

For reference, I am currently doing:

test(..., args: [turbo_module.full_path(), meson.source_root() / 'test' / 'examples'])

https://github.com/JuliaSIMD/LoopModels/blob/f726b90f3417aa7049aaa002f3b2e79357947ea6/meson.build#L34
and then using these to popen (which runs an executable, and returns a file handle to the stdout) and fopen:

  std::string modulePath = argv[1];
  std::string examplesPath = argv[2];
  printf("modulePath: %s\n", modulePath.c_str());
  printf("examplesPath: %s\n", examplesPath.c_str());
  std::string fileRoot = examplesPath + std::string("/triangular_solve.");
  auto cmd =
    std::string(
      "opt -mcpu=skylake-avx512 --disable-output -load-pass-plugin=") +
    modulePath +
    std::string(" -passes='turbo-loop' -pass-remarks-analysis='turbo-loop' ") +
    fileRoot + std::string("ll 2>&1");
  printf("cmd: %s", cmd.c_str());
  std::string txtfile = fileRoot + std::string("txt");

  FILE *fpopt = popen(cmd.c_str(), "r");
  FILE *fptxt = fopen(txtfile.c_str(), "r");

https://github.com/JuliaSIMD/LoopModels/blob/f726b90f3417aa7049aaa002f3b2e79357947ea6/test/remarks_test.cpp#L9-L24

So an example cmd (this one taken from a CI log) that gets generated and run is:

opt -mcpu=skylake-avx512 --disable-output -load-pass-plugin=/Users/runner/work/LoopModels/LoopModels/builddir/libTurboLoop.dylib -passes='turbo-loop' -pass-remarks-analysis='turbo-loop' /Users/runner/work/LoopModels/LoopModels/test/examples/triangular_solve.ll 2>&1

This seems to work: tests pass locally and on CI.

But I'm open to a better way to do things.

To be clear, "2." and "3." are both simply files that are checked into the repo. They aren't produced by a build, but used for testing (I'll likely add more such files later, I just wanted to get an example working first for automatic regression checking).
This is why I passed the path for the directory containing these files as meson.source_root() / 'test' / 'examples'.

But, because I may change these files, perhaps I should also declare them as dependencies?