diff options
Diffstat (limited to 'vendor/compiler_builtins/libm/src/math/fma.rs')
-rw-r--r-- | vendor/compiler_builtins/libm/src/math/fma.rs | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/vendor/compiler_builtins/libm/src/math/fma.rs b/vendor/compiler_builtins/libm/src/math/fma.rs index 516f9ad3a..f9a86dc60 100644 --- a/vendor/compiler_builtins/libm/src/math/fma.rs +++ b/vendor/compiler_builtins/libm/src/math/fma.rs @@ -126,8 +126,8 @@ pub fn fma(x: f64, y: f64, z: f64) -> f64 { rlo = res; rhi = rhi.wrapping_sub(zhi.wrapping_add(borrow as u64)); if (rhi >> 63) != 0 { - rlo = (-(rlo as i64)) as u64; - rhi = (-(rhi as i64)) as u64 - (rlo != 0) as u64; + rlo = (rlo as i64).wrapping_neg() as u64; + rhi = (rhi as i64).wrapping_neg() as u64 - (rlo != 0) as u64; sign = (sign == 0) as i32; } nonzero = (rhi != 0) as i32; @@ -232,4 +232,12 @@ mod tests { -3991680619069439e277 ); } + + #[test] + fn fma_underflow() { + assert_eq!( + fma(1.1102230246251565e-16, -9.812526705433188e-305, 1.0894e-320), + 0.0, + ); + } } |