5023691213
implement `va_arg` for x86_64 systemv
tracking issue: https://github.com/rust-lang/rust/issues/44930
Turns out LLVM's `va_arg` is also unreliable for this target.
https://github.com/llvm/llvm-project/issues/141361
So, like clang, we implement our own. I used
- the spec at https://gitlab.com/x86-psABIs/x86-64-ABI
- the clang implementation at 9a440f8477/clang/lib/CodeGen/Targets/X86.cpp (L3041)
We can take a bunch of shortcuts because the return type of `va_list` must implement `VaArgSafe`. I also extended some of the tests, because up to 11 floats can be stored in the `reg_safe_area` for this calling convention.
r? `@workingjubilee`
`@rustbot` label +F-c_variadic
try-job: x86_64-apple-1
The run-make test suite
The run-make test suite contains tests which are the most flexible out of all the rust-lang/rust test suites. run-make tests can basically contain arbitrary code, and are supported by the run_make_support library.
Infrastructure
A run-make test is a test recipe source file rmake.rs accompanied by its parent directory (e.g. tests/run-make/foo/rmake.rs is the foo run-make test).
The implementation for collecting and building the rmake.rs recipes are in src/tools/compiletest/src/runtest.rs, in run_rmake_test.
The setup for the rmake.rs can be summarized as a 3-stage process:
-
First, we build the
run_make_supportlibrary in bootstrap as a tool lib. -
Then, we compile the
rmake.rs"recipe" linking the support library and its dependencies in, and provide a bunch of env vars. We setup a directory structure withinbuild/<target>/test/run-make/<test-name>/ rmake.exe # recipe binary rmake_out/ # sources from test sources copied overand copy non-
rmake.rsinput support files over tormake_out/. The support library is made available as an extern prelude. -
Finally, we run the recipe binary and set
rmake_out/as the working directory.