/// Absolute value (magnitude) (f32) /// Calculates the absolute value (magnitude) of the argument `x`, /// by direct manipulation of the bit representation of `x`. #[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)] pub fn fabsf(x: f32) -> f32 { // On wasm32 we know that LLVM's intrinsic will compile to an optimized // `f32.abs` native instruction, so we can leverage this for both code size // and speed. llvm_intrinsically_optimized! { #[cfg(target_arch = "wasm32")] { return unsafe { ::core::intrinsics::fabsf32(x) } } } f32::from_bits(x.to_bits() & 0x7fffffff) } // PowerPC tests are failing on LLVM 13: https://github.com/rust-lang/rust/issues/88520 #[cfg(not(target_arch = "powerpc64"))] #[cfg(test)] mod tests { use super::*; use core::f32::*; #[test] fn sanity_check() { assert_eq!(fabsf(-1.0), 1.0); assert_eq!(fabsf(2.8), 2.8); } /// The spec: https://en.cppreference.com/w/cpp/numeric/math/fabs #[test] fn spec_tests() { assert!(fabsf(NAN).is_nan()); for f in [0.0, -0.0].iter().copied() { assert_eq!(fabsf(f), 0.0); } for f in [INFINITY, NEG_INFINITY].iter().copied() { assert_eq!(fabsf(f), INFINITY); } } }