llc only supports one input file

[otsmr]

When the target library is compiled to a static library with the following CMAKE options:

add_library(testbase STATIC ${SOURCE_FILES})
llvmir_attach_bc_target(testbase_bc testbase)
llvmir_attach_opt_pass_target(testbase_opt testbase_bc -load-pass-plugin=${LLVM_PASS_CTRACE} -passes=ctrace)
llvmir_attach_obj_target(testbase_obj testbase_opt)
llvmir_attach_library(testbase_instrumented testbase_obj STATIC)

I got the following error message:

FAILED: llvm-ir/testbase_obj/testbase_obj.o /[...]/build/llvm-ir/testbase_obj/testbase_obj.o
cd /[...]/build && llc -filetype=obj -o /[...]/build/llvm-ir/testbase_obj/testbase_obj.o /[...]/build/llvm-ir/testbase_opt/Test1.bc /[...]/build/llvm-ir/testbase_opt/Test2.bc /[...]/build/llvm-ir/testbase_opt/Test3.bc /[...]/build/llvm-ir/testbase_opt/Test4.bc
llc: Too many positional arguments specified!
Can specify at most 1 positional arguments: See: llc --help
ninja: build stopped: subcommand failed.

The problem is that LLC only supports one input file. This PR fixes this issue by going over each bc file separately.

[compor]

Could you add a minimal example that reproduces the issue? You can add it as example04 in the top-level directory.

I plan to write some basic tests and move the examples to form a small test suite.

[compor]

why do we need this flag here?

[otsmr]

I added this flag because the compiler complained in my real project that I needed to recompile with -fPIC.

[compor]

I'd rather not have project-specific options hardcoded like this.
This command handles other args and passes them unaltered using ${LLVMIR_ATTACH_UNPARSED_ARGUMENTS}.

Can you please try your project with defining that flag in your CMakeLists.txt?

[compor]

Isn't SHORT_NAME still useful for the multiple output files generated by the changes in your PR?

[otsmr]

In my project it worked fine without it, so I assumed that I could just remove it.

[compor]

Can you please reintroduce it and check that your project still works?
Just because it's not needed in your configuration doesn't mean that wasn't introduced for a reason initially.

[compor]

I'd rather not have project-specific options hardcoded like this.
This command handles other args and passes them unaltered using ${LLVMIR_ATTACH_UNPARSED_ARGUMENTS}.

Can you please try your project with defining that flag in your CMakeLists.txt?

[compor]

Can you please reintroduce it and check that your project still works?
Just because it's not needed in your configuration doesn't mean that wasn't introduced for a reason initially.