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use std::env;
fn main() {
println!("cargo:rerun-if-changed=build.rs");
#[cfg(feature = "musl-reference-tests")]
musl_reference_tests::generate();
if !cfg!(feature = "checked") {
let lvl = env::var("OPT_LEVEL").unwrap();
if lvl != "0" {
println!("cargo:rustc-cfg=assert_no_panic");
}
}
}
#[cfg(feature = "musl-reference-tests")]
mod musl_reference_tests {
use rand::seq::SliceRandom;
use rand::Rng;
use std::env;
use std::fs;
use std::process::Command;
// Number of tests to generate for each function
const NTESTS: usize = 500;
// These files are all internal functions or otherwise miscellaneous, not
// defining a function we want to test.
const IGNORED_FILES: &[&str] = &[
"fenv.rs",
// These are giving slightly different results compared to musl
"lgamma.rs",
"lgammaf.rs",
"tgamma.rs",
"j0.rs",
"j0f.rs",
"jn.rs",
"jnf.rs",
"j1.rs",
"j1f.rs",
];
struct Function {
name: String,
args: Vec<Ty>,
ret: Vec<Ty>,
tests: Vec<Test>,
}
enum Ty {
F32,
F64,
I32,
Bool,
}
struct Test {
inputs: Vec<i64>,
outputs: Vec<i64>,
}
pub fn generate() {
let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap();
if target_arch == "powerpc64" {
return;
}
let files = fs::read_dir("src/math")
.unwrap()
.map(|f| f.unwrap().path())
.collect::<Vec<_>>();
let mut math = Vec::new();
for file in files {
if IGNORED_FILES.iter().any(|f| file.ends_with(f)) {
continue;
}
println!("generating musl reference tests in {:?}", file);
let contents = fs::read_to_string(file).unwrap();
let mut functions = contents.lines().filter(|f| f.starts_with("pub fn"));
while let Some(function_to_test) = functions.next() {
math.push(parse(function_to_test));
}
}
// Generate a bunch of random inputs for each function. This will
// attempt to generate a good set of uniform test cases for exercising
// all the various functionality.
generate_random_tests(&mut math, &mut rand::thread_rng());
// After we have all our inputs, use the x86_64-unknown-linux-musl
// target to generate the expected output.
generate_test_outputs(&mut math);
//panic!("Boo");
// ... and now that we have both inputs and expected outputs, do a bunch
// of codegen to create the unit tests which we'll actually execute.
generate_unit_tests(&math);
}
/// A "poor man's" parser for the signature of a function
fn parse(s: &str) -> Function {
let s = eat(s, "pub fn ");
let pos = s.find('(').unwrap();
let name = &s[..pos];
let s = &s[pos + 1..];
let end = s.find(')').unwrap();
let args = s[..end]
.split(',')
.map(|arg| {
let colon = arg.find(':').unwrap();
parse_ty(arg[colon + 1..].trim())
})
.collect::<Vec<_>>();
let tail = &s[end + 1..];
let tail = eat(tail, " -> ");
let ret = parse_retty(tail.replace("{", "").trim());
return Function {
name: name.to_string(),
args,
ret,
tests: Vec::new(),
};
fn parse_ty(s: &str) -> Ty {
match s {
"f32" => Ty::F32,
"f64" => Ty::F64,
"i32" => Ty::I32,
"bool" => Ty::Bool,
other => panic!("unknown type `{}`", other),
}
}
fn parse_retty(s: &str) -> Vec<Ty> {
match s {
"(f32, f32)" => vec![Ty::F32, Ty::F32],
"(f32, i32)" => vec![Ty::F32, Ty::I32],
"(f64, f64)" => vec![Ty::F64, Ty::F64],
"(f64, i32)" => vec![Ty::F64, Ty::I32],
other => vec![parse_ty(other)],
}
}
fn eat<'a>(s: &'a str, prefix: &str) -> &'a str {
if s.starts_with(prefix) {
&s[prefix.len()..]
} else {
panic!("{:?} didn't start with {:?}", s, prefix)
}
}
}
fn generate_random_tests<R: Rng>(functions: &mut [Function], rng: &mut R) {
for function in functions {
for _ in 0..NTESTS {
function.tests.push(generate_test(function, rng));
}
}
fn generate_test<R: Rng>(function: &Function, rng: &mut R) -> Test {
let mut inputs = function
.args
.iter()
.map(|ty| ty.gen_i64(rng))
.collect::<Vec<_>>();
// First argument to this function appears to be a number of
// iterations, so passing in massive random numbers causes it to
// take forever to execute, so make sure we're not running random
// math code until the heat death of the universe.
if function.name == "jn" || function.name == "jnf" {
inputs[0] &= 0xffff;
}
Test {
inputs,
// zero output for now since we'll generate it later
outputs: vec![],
}
}
}
impl Ty {
fn gen_i64<R: Rng>(&self, r: &mut R) -> i64 {
use std::f32;
use std::f64;
return match self {
Ty::F32 => {
if r.gen_range(0, 20) < 1 {
let i = *[f32::NAN, f32::INFINITY, f32::NEG_INFINITY]
.choose(r)
.unwrap();
i.to_bits().into()
} else {
r.gen::<f32>().to_bits().into()
}
}
Ty::F64 => {
if r.gen_range(0, 20) < 1 {
let i = *[f64::NAN, f64::INFINITY, f64::NEG_INFINITY]
.choose(r)
.unwrap();
i.to_bits() as i64
} else {
r.gen::<f64>().to_bits() as i64
}
}
Ty::I32 => {
if r.gen_range(0, 10) < 1 {
let i = *[i32::max_value(), 0, i32::min_value()].choose(r).unwrap();
i.into()
} else {
r.gen::<i32>().into()
}
}
Ty::Bool => r.gen::<bool>() as i64,
};
}
fn libc_ty(&self) -> &'static str {
match self {
Ty::F32 => "f32",
Ty::F64 => "f64",
Ty::I32 => "i32",
Ty::Bool => "i32",
}
}
fn libc_pty(&self) -> &'static str {
match self {
Ty::F32 => "*mut f32",
Ty::F64 => "*mut f64",
Ty::I32 => "*mut i32",
Ty::Bool => "*mut i32",
}
}
fn default(&self) -> &'static str {
match self {
Ty::F32 => "0_f32",
Ty::F64 => "0_f64",
Ty::I32 => "0_i32",
Ty::Bool => "false",
}
}
fn to_i64(&self) -> &'static str {
match self {
Ty::F32 => ".to_bits() as i64",
Ty::F64 => ".to_bits() as i64",
Ty::I32 => " as i64",
Ty::Bool => " as i64",
}
}
}
fn generate_test_outputs(functions: &mut [Function]) {
let mut src = String::new();
let dst = std::env::var("OUT_DIR").unwrap();
// Generate a program which will run all tests with all inputs in
// `functions`. This program will write all outputs to stdout (in a
// binary format).
src.push_str("use std::io::Write;");
src.push_str("fn main() {");
src.push_str("let mut result = Vec::new();");
for function in functions.iter_mut() {
src.push_str("unsafe {");
src.push_str("extern { fn ");
src.push_str(&function.name);
src.push_str("(");
let (ret, retptr) = match function.name.as_str() {
"sincos" | "sincosf" => (None, &function.ret[..]),
_ => (Some(&function.ret[0]), &function.ret[1..]),
};
for (i, arg) in function.args.iter().enumerate() {
src.push_str(&format!("arg{}: {},", i, arg.libc_ty()));
}
for (i, ret) in retptr.iter().enumerate() {
src.push_str(&format!("argret{}: {},", i, ret.libc_pty()));
}
src.push_str(")");
if let Some(ty) = ret {
src.push_str(" -> ");
src.push_str(ty.libc_ty());
}
src.push_str("; }");
src.push_str(&format!("static TESTS: &[[i64; {}]]", function.args.len()));
src.push_str(" = &[");
for test in function.tests.iter() {
src.push_str("[");
for val in test.inputs.iter() {
src.push_str(&val.to_string());
src.push_str(",");
}
src.push_str("],");
}
src.push_str("];");
src.push_str("for test in TESTS {");
for (i, arg) in retptr.iter().enumerate() {
src.push_str(&format!("let mut argret{} = {};", i, arg.default()));
}
src.push_str("let output = ");
src.push_str(&function.name);
src.push_str("(");
for (i, arg) in function.args.iter().enumerate() {
src.push_str(&match arg {
Ty::F32 => format!("f32::from_bits(test[{}] as u32)", i),
Ty::F64 => format!("f64::from_bits(test[{}] as u64)", i),
Ty::I32 => format!("test[{}] as i32", i),
Ty::Bool => format!("test[{}] as i32", i),
});
src.push_str(",");
}
for (i, _) in retptr.iter().enumerate() {
src.push_str(&format!("&mut argret{},", i));
}
src.push_str(");");
if let Some(ty) = &ret {
src.push_str(&format!("let output = output{};", ty.to_i64()));
src.push_str("result.extend_from_slice(&output.to_le_bytes());");
}
for (i, ret) in retptr.iter().enumerate() {
src.push_str(&format!(
"result.extend_from_slice(&(argret{}{}).to_le_bytes());",
i,
ret.to_i64(),
));
}
src.push_str("}");
src.push_str("}");
}
src.push_str("std::io::stdout().write_all(&result).unwrap();");
src.push_str("}");
let path = format!("{}/gen.rs", dst);
fs::write(&path, src).unwrap();
// Make it somewhat pretty if something goes wrong
drop(Command::new("rustfmt").arg(&path).status());
// Compile and execute this tests for the musl target, assuming we're an
// x86_64 host effectively.
let status = Command::new("rustc")
.current_dir(&dst)
.arg(&path)
.arg("--target=x86_64-unknown-linux-musl")
.status()
.unwrap();
assert!(status.success());
let output = Command::new("./gen").current_dir(&dst).output().unwrap();
assert!(output.status.success());
assert!(output.stderr.is_empty());
// Map all the output bytes back to an `i64` and then shove it all into
// the expected results.
let mut results = output.stdout.chunks_exact(8).map(|buf| {
let mut exact = [0; 8];
exact.copy_from_slice(buf);
i64::from_le_bytes(exact)
});
for f in functions.iter_mut() {
for test in f.tests.iter_mut() {
test.outputs = (0..f.ret.len()).map(|_| results.next().unwrap()).collect();
}
}
assert!(results.next().is_none());
}
/// Codegens a file which has a ton of `#[test]` annotations for all the
/// tests that we generated above.
fn generate_unit_tests(functions: &[Function]) {
let mut src = String::new();
let dst = std::env::var("OUT_DIR").unwrap();
for function in functions {
src.push_str("#[test]");
src.push_str("fn ");
src.push_str(&function.name);
src.push_str("_matches_musl() {");
src.push_str(&format!(
"static TESTS: &[([i64; {}], [i64; {}])]",
function.args.len(),
function.ret.len(),
));
src.push_str(" = &[");
for test in function.tests.iter() {
src.push_str("([");
for val in test.inputs.iter() {
src.push_str(&val.to_string());
src.push_str(",");
}
src.push_str("],");
src.push_str("[");
for val in test.outputs.iter() {
src.push_str(&val.to_string());
src.push_str(",");
}
src.push_str("],");
src.push_str("),");
}
src.push_str("];");
src.push_str("for (test, expected) in TESTS {");
src.push_str("let output = ");
src.push_str(&function.name);
src.push_str("(");
for (i, arg) in function.args.iter().enumerate() {
src.push_str(&match arg {
Ty::F32 => format!("f32::from_bits(test[{}] as u32)", i),
Ty::F64 => format!("f64::from_bits(test[{}] as u64)", i),
Ty::I32 => format!("test[{}] as i32", i),
Ty::Bool => format!("test[{}] as i32", i),
});
src.push_str(",");
}
src.push_str(");");
for (i, ret) in function.ret.iter().enumerate() {
let get = if function.ret.len() == 1 {
String::new()
} else {
format!(".{}", i)
};
src.push_str(&(match ret {
Ty::F32 => format!("if _eqf(output{}, f32::from_bits(expected[{}] as u32)).is_ok() {{ continue }}", get, i),
Ty::F64 => format!("if _eq(output{}, f64::from_bits(expected[{}] as u64)).is_ok() {{ continue }}", get, i),
Ty::I32 => format!("if output{} as i64 == expected[{}] {{ continue }}", get, i),
Ty::Bool => unreachable!(),
}));
}
src.push_str(
r#"
panic!("INPUT: {:?} EXPECTED: {:?} ACTUAL {:?}", test, expected, output);
"#,
);
src.push_str("}");
src.push_str("}");
}
let path = format!("{}/musl-tests.rs", dst);
fs::write(&path, src).unwrap();
// Try to make it somewhat pretty
drop(Command::new("rustfmt").arg(&path).status());
}
}