address review

Author: LorrensP-2158466

src/tools/miri/src/helpers.rs

@@ -227,9 +227,8 @@ where
     let one = IeeeFloat::<S>::one();
     let two = IeeeFloat::<S>::two();
     let pi = IeeeFloat::<S>::pi();
-    let pi_over_2 = IeeeFloat::<S>::frac_pi_2();
+    let pi_over_2 = (pi / two).value;
 
-    // Exclusive ranges are made using next_up/next_down.
     match intrinsic_name {
         // sin, cos, tanh: [-1, 1]
         #[rustfmt::skip]
@@ -254,20 +253,17 @@ where
         "asinf" | "asin" => val.clamp(pi.neg(), pi),
 
         // atan: (-π/2, +π/2)
-        "atanf" | "atan" => val.clamp(pi_over_2.neg().next_up().value, pi_over_2.next_down().value),
+        "atanf" | "atan" => val.clamp(pi_over_2.neg(), pi_over_2),
 
         // erfc: (-1, 1)
-        "erff" | "erf" => val.clamp(one.neg().next_up().value, one.next_down().value),
+        "erff" | "erf" => val.clamp(one.neg(), one),
 
         // erfc: (0, 2)
-        "erfcf" | "erfc" => val.clamp(zero.next_up().value, two.next_down().value),
+        "erfcf" | "erfc" => val.clamp(zero, two),
 
         // atan2(y, x): arctan(y/x) in [−π, +π]
         "atan2f" | "atan2" => val.clamp(pi.neg(), pi),
 
-        // FIXME: According to Wolfram Alpha, the range of ln(gamma) is [-0.121486, +INF]. What to do?
-        "lgammaf_r" | "lgamma_r" => val,
-
         _ => val,
     }
 }
@@ -1323,12 +1319,12 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
         IeeeFloat<S>: IeeeExt,
     {
         let this = self.eval_context_mut();
-        let zero = IeeeFloat::<S>::ZERO;
         let one = IeeeFloat::<S>::one();
+        let two = IeeeFloat::<S>::two();
         let three = IeeeFloat::<S>::three();
         let pi = IeeeFloat::<S>::pi();
-        let pi_over_2 = IeeeFloat::<S>::frac_pi_2();
-        let pi_over_4 = IeeeFloat::<S>::frac_pi_4();
+        let pi_over_2 = (pi / two).value;
+        let pi_over_4 = (pi_over_2 / two).value;
 
         Some(match (intrinsic_name, args) {
             // cos(±0) and cosh(±0)= 1
@@ -1349,11 +1345,6 @@ pub trait EvalContextExt<'tcx>: crate::MiriInterpCxExt<'tcx> {
             // erfc(-INF) = 2
             ("erfcf" | "erfc", [input]) if input.is_neg_infinity() => (one + one).value,
 
-            // erfc(+INF) = 0
-            // REVIEW/HELP: for some reason the tests fail because erfc(+INF) = 1e-45. Which is weird because
-            // no error can be applied to 0. Checked and this does not happen without Miri.
-            ("erfcf" | "erfc", [input]) if input.is_pos_infinity() => zero,
-
             // hypot(x, ±0) = abs(x), if x is not a NaN.
             ("_hypotf" | "hypotf" | "_hypot" | "hypot", [x, y]) if !x.is_nan() && y.is_zero() =>
                 x.abs(),

src/tools/miri/src/math.rs

@@ -176,17 +176,9 @@ pub trait IeeeExt: rustc_apfloat::Float {
         Self::from_u128(3).value
     }
 
-    // Some PI values we use:
-
     /// Equal PI.
     fn pi() -> Self;
 
-    /// Equal to PI/2.
-    fn frac_pi_2() -> Self;
-
-    /// Equal to PI/4.
-    fn frac_pi_4() -> Self;
-
     #[inline]
     fn clamp(self, min: Self, max: Self) -> Self {
         self.maximum(min).minimum(max)
@@ -200,15 +192,6 @@ macro_rules! impl_ieee_pi {
             fn pi() -> Self {
                 Self::from_bits($float_ty::consts::PI.to_bits() as _)
             }
-            #[inline]
-            fn frac_pi_2() -> Self {
-                Self::from_bits($float_ty::consts::FRAC_PI_2.to_bits() as _)
-            }
-
-            #[inline]
-            fn frac_pi_4() -> Self {
-                Self::from_bits($float_ty::consts::FRAC_PI_4.to_bits() as _)
-            }
         }
     };
 }

src/tools/miri/tests/pass/float.rs

@@ -1220,8 +1220,8 @@ pub fn libm() {
             assert_eq!($float_type::atan2(NEG_INFINITY, 1.0), -FRAC_PI_2, "atan2(-∞, y) returns -π/2 for finite y");
 
             // atan2(±∞, −∞) = ±3π/4
-            // assert_eq!($float_type::atan2(INFINITY, NEG_INFINITY), 3.0 * FRAC_PI_4, "atan2(+∞, −∞) = 3π/4");
-            // assert_eq!($float_type::atan2(NEG_INFINITY, NEG_INFINITY), -3.0 * FRAC_PI_4, "atan2(-∞, −∞) = -3π/4");
+            assert_eq!($float_type::atan2(INFINITY, NEG_INFINITY), 3.0 * FRAC_PI_4, "atan2(+∞, −∞) = 3π/4");
+            assert_eq!($float_type::atan2(NEG_INFINITY, NEG_INFINITY), -3.0 * FRAC_PI_4, "atan2(-∞, −∞) = -3π/4");
 
             // atan2(±∞, +∞) = ±π/4
             assert_eq!($float_type::atan2(INFINITY, INFINITY), FRAC_PI_4, "atan2(+∞, +∞) = π/4");