compiler-builtins-zynq/src/qc.rs

312 lines
11 KiB
Rust

// When testing functions, QuickCheck (QC) uses small values for integer (`u*`/`i*`) arguments
// (~ `[-100, 100]`), but these values don't stress all the code paths in our intrinsics. Here we
// create newtypes over the primitive integer types with the goal of having full control over the
// random values that will be used to test our intrinsics.
use std::boxed::Box;
use std::fmt;
use core::{f32, f64};
use quickcheck::{Arbitrary, Gen};
use int::LargeInt;
use float::Float;
// Generates values in the full range of the integer type
macro_rules! arbitrary {
($TY:ident : $ty:ident) => {
#[derive(Clone, Copy, PartialEq)]
pub struct $TY(pub $ty);
impl Arbitrary for $TY {
fn arbitrary<G>(g: &mut G) -> $TY
where G: Gen
{
// NOTE Generate edge cases with a 10% chance
let t = if g.gen_weighted_bool(10) {
*g.choose(&[
$ty::min_value(),
0,
$ty::max_value(),
]).unwrap()
} else {
g.gen()
};
$TY(t)
}
fn shrink(&self) -> Box<Iterator<Item=$TY>> {
struct Shrinker {
x: $ty,
}
impl Iterator for Shrinker {
type Item = $TY;
fn next(&mut self) -> Option<$TY> {
self.x /= 2;
if self.x == 0 {
None
} else {
Some($TY(self.x))
}
}
}
if self.0 == 0 {
::quickcheck::empty_shrinker()
} else {
Box::new(Shrinker { x: self.0 })
}
}
}
impl fmt::Debug for $TY {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
fmt::Debug::fmt(&self.0, f)
}
}
}
}
arbitrary!(I32: i32);
arbitrary!(U32: u32);
// These integers are "too large". If we generate e.g. `u64` values in the full range then there's
// only `1 / 2^32` chance of seeing a value smaller than `2^32` (i.e. whose higher "word" (32-bits)
// is `0`)! But this is an important group of values to tests because we have special code paths for
// them. Instead we'll generate e.g. `u64` integers this way: uniformly pick between (a) setting the
// low word to 0 and generating a random high word, (b) vice versa: high word to 0 and random low
// word or (c) generate both words randomly. This let's cover better the code paths in our
// intrinsics.
macro_rules! arbitrary_large {
($TY:ident : $ty:ident) => {
#[derive(Clone, Copy, PartialEq)]
pub struct $TY(pub $ty);
impl Arbitrary for $TY {
fn arbitrary<G>(g: &mut G) -> $TY
where G: Gen
{
// NOTE Generate edge cases with a 10% chance
let t = if g.gen_weighted_bool(10) {
*g.choose(&[
$ty::min_value(),
0,
$ty::max_value(),
]).unwrap()
} else {
match g.gen_range(0, 3) {
0 => $ty::from_parts(g.gen(), g.gen()),
1 => $ty::from_parts(0, g.gen()),
2 => $ty::from_parts(g.gen(), 0),
_ => unreachable!(),
}
};
$TY(t)
}
fn shrink(&self) -> Box<Iterator<Item=$TY>> {
struct Shrinker {
x: $ty,
}
impl Iterator for Shrinker {
type Item = $TY;
fn next(&mut self) -> Option<$TY> {
self.x /= 2;
if self.x == 0 {
None
} else {
Some($TY(self.x))
}
}
}
if self.0 == 0 {
::quickcheck::empty_shrinker()
} else {
Box::new(Shrinker { x: self.0 })
}
}
}
impl fmt::Debug for $TY {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
fmt::Debug::fmt(&self.0, f)
}
}
}
}
arbitrary_large!(I64: i64);
arbitrary_large!(U64: u64);
arbitrary_large!(I128: i128);
arbitrary_large!(U128: u128);
macro_rules! arbitrary_float {
($TY:ident : $ty:ident) => {
#[derive(Clone, Copy)]
pub struct $TY(pub $ty);
impl Arbitrary for $TY {
fn arbitrary<G>(g: &mut G) -> $TY
where G: Gen
{
let special = [
-0.0, 0.0, $ty::NAN, $ty::INFINITY, -$ty::INFINITY
];
if g.gen_weighted_bool(10) { // Random special case
$TY(*g.choose(&special).unwrap())
} else if g.gen_weighted_bool(10) { // NaN variants
let sign: bool = g.gen();
let exponent: <$ty as Float>::Int = g.gen();
let significand: <$ty as Float>::Int = 0;
$TY($ty::from_parts(sign, exponent, significand))
} else if g.gen() { // Denormalized
let sign: bool = g.gen();
let exponent: <$ty as Float>::Int = 0;
let significand: <$ty as Float>::Int = g.gen();
$TY($ty::from_parts(sign, exponent, significand))
} else { // Random anything
let sign: bool = g.gen();
let exponent: <$ty as Float>::Int = g.gen();
let significand: <$ty as Float>::Int = g.gen();
$TY($ty::from_parts(sign, exponent, significand))
}
}
fn shrink(&self) -> Box<Iterator<Item=$TY>> {
::quickcheck::empty_shrinker()
}
}
impl fmt::Debug for $TY {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
fmt::Debug::fmt(&self.0, f)
}
}
impl PartialEq for $TY {
fn eq(&self, other: &$TY) -> bool {
self.0.eq_repr(other.0)
}
}
}
}
arbitrary_float!(F32: f32);
arbitrary_float!(F64: f64);
// Convenience macro to test intrinsics against their reference implementations.
//
// Each intrinsic is tested against both the `gcc_s` library as well as
// `compiler-rt`. These libraries are defined in the `gcc_s` crate as well as
// the `compiler-rt` crate in this repository. Both load a dynamic library and
// lookup symbols through that dynamic library to ensure that we're using the
// right intrinsic.
//
// This macro hopefully allows you to define a bare minimum of how to test an
// intrinsic without worrying about these implementation details. A sample
// invocation looks like:
//
//
// check! {
// // First argument is the function we're testing (either from this lib
// // or a dynamically loaded one. Further arguments are all generated by
// // quickcheck.
// fn __my_intrinsic(f: extern fn(i32) -> i32,
// a: I32)
// -> Option<(i32, i64)> {
//
// // Discard tests by returning Some
// if a.0 == 0 {
// return None
// }
//
// // Return the result via `Some` if the test can run
// let mut other_result = 0;
// let result = f(a.0, &mut other_result);
// Some((result, other_result))
// }
// }
//
// If anything returns `None` then the test is discarded, otherwise the two
// results are compared for equality and the test fails if this equality check
// fails.
macro_rules! check {
($(
$(#[$cfg:meta])*
fn $name:ident($f:ident: extern $abi:tt fn($($farg:ty),*) -> $fret:ty,
$($arg:ident: $t:ty),*)
-> Option<$ret:ty>
{
$($code:tt)*
}
)*) => (
$(
$(#[$cfg])*
fn $name($f: extern $abi fn($($farg),*) -> $fret,
$($arg: $t),*) -> Option<$ret> {
$($code)*
}
)*
mod _test {
use qc::*;
use std::mem;
use quickcheck::TestResult;
$(
$(#[$cfg])*
#[test]
fn $name() {
fn my_check($($arg:$t),*) -> TestResult {
let my_answer = super::$name(super::super::$name,
$($arg),*);
let compiler_rt_fn = ::compiler_rt::get(stringify!($name));
let compiler_rt_answer = unsafe {
super::$name(mem::transmute(compiler_rt_fn),
$($arg),*)
};
let gcc_s_answer =
match ::gcc_s::get(stringify!($name)) {
Some(f) => unsafe {
Some(super::$name(mem::transmute(f),
$($arg),*))
},
None => None,
};
let print_values = || {
print!("{} - Args: ", stringify!($name));
$(print!("{:?} ", $arg);)*
print!("\n");
println!(" compiler-builtins: {:?}", my_answer);
println!(" compiler_rt: {:?}", compiler_rt_answer);
println!(" gcc_s: {:?}", gcc_s_answer);
};
if my_answer != compiler_rt_answer {
print_values();
TestResult::from_bool(false)
} else if gcc_s_answer.is_some() &&
my_answer != gcc_s_answer.unwrap() {
print_values();
TestResult::from_bool(false)
} else {
TestResult::from_bool(true)
}
}
::quickcheck::quickcheck(my_check as fn($($t),*) -> TestResult)
}
)*
}
)
}