56 lines
2.4 KiB
Rust
56 lines
2.4 KiB
Rust
// This test makes sure that PGO profiling data leads to cold functions being
|
|
// marked as `cold` and hot functions with `inlinehint`.
|
|
// The test program contains an `if` where actual execution only ever takes the
|
|
// `else` branch. Accordingly, we expect the function that is never called to
|
|
// be marked as cold.
|
|
// See https://github.com/rust-lang/rust/pull/60262
|
|
|
|
//@ needs-profiler-support
|
|
//@ ignore-cross-compile
|
|
|
|
use run_make_support::{
|
|
cwd, has_extension, has_prefix, llvm_filecheck, llvm_profdata, rfs, run_with_args, rustc,
|
|
shallow_find_files,
|
|
};
|
|
|
|
fn main() {
|
|
// Compile the test program with instrumentation
|
|
// Disable the pre-inlining pass (i.e. a pass that does some inlining before
|
|
// it adds the profiling instrumentation). Disabling this pass leads to
|
|
// rather predictable IR which we need for this test to be stable.
|
|
rustc()
|
|
.opt_level("2")
|
|
.codegen_units(1)
|
|
.arg("-Cllvm-args=-disable-preinline")
|
|
.profile_generate(cwd())
|
|
.input("main.rs")
|
|
.run();
|
|
// Run it in order to generate some profiling data
|
|
run_with_args("main", &["some-argument"]);
|
|
// Postprocess the profiling data so it can be used by the compiler
|
|
let profraw_files = shallow_find_files(cwd(), |path| {
|
|
has_prefix(path, "default") && has_extension(path, "profraw")
|
|
});
|
|
let profraw_file = profraw_files.get(0).unwrap();
|
|
llvm_profdata().merge().output("merged.profdata").input(profraw_file).run();
|
|
// Compile the test program again, making use of the profiling data
|
|
rustc()
|
|
.opt_level("2")
|
|
.codegen_units(1)
|
|
.arg("-Cllvm-args=-disable-preinline")
|
|
.profile_use("merged.profdata")
|
|
.emit("llvm-ir")
|
|
.input("main.rs")
|
|
.run();
|
|
// Check that the generate IR contains some things that we expect.
|
|
// We feed the file into LLVM FileCheck tool *with its lines reversed* so that we see the
|
|
// line with the function name before the line with the function attributes.
|
|
// FileCheck only supports checking that something matches on the next line,
|
|
// but not if something matches on the previous line.
|
|
let ir = rfs::read_to_string("main.ll");
|
|
let lines: Vec<_> = ir.lines().rev().collect();
|
|
let mut reversed_ir = lines.join("\n");
|
|
reversed_ir.push('\n');
|
|
llvm_filecheck().patterns("filecheck-patterns.txt").stdin_buf(reversed_ir.as_bytes()).run();
|
|
}
|