Update precision based on failures from extensive tests

Author: tgross35

crates/libm-test/src/precision.rs

@@ -26,7 +26,7 @@ pub fn default_ulp(ctx: &CheckCtx) -> u32 {
         // Overrides that apply to either basis
         (_, Id::J0 | Id::J0f | Id::J1 | Id::J1f) => {
             // Results seem very target-dependent
-            if cfg!(target_arch = "x86_64") { 4000 } else { 800_000 }
+            if cfg!(target_arch = "x86_64") { 40_000 } else { 800_000 }
         }
         (_, Id::Jn | Id::Jnf) => 1000,
 
@@ -45,6 +45,7 @@ pub fn default_ulp(ctx: &CheckCtx) -> u32 {
         (Mpfr, Id::Acoshf) => 4,
         (Mpfr, Id::Asinh | Id::Asinhf) => 2,
         (Mpfr, Id::Atanh | Id::Atanhf) => 2,
+        (Mpfr, Id::Atan2) => 2,
         (Mpfr, Id::Exp10 | Id::Exp10f) => 6,
         (Mpfr, Id::Lgamma | Id::LgammaR | Id::Lgammaf | Id::LgammafR) => 16,
         (Mpfr, Id::Sinh | Id::Sinhf) => 2,
@@ -128,6 +129,16 @@ impl MaybeOverride<(f32,)> for SpecialCase {
             return XFAIL;
         }
 
+        if ctx.fn_name == "lgammaf"
+            || ctx.fn_name == "lgammaf_r"
+                && input.0 > 4e36
+                && expected.is_infinite()
+                && !actual.is_infinite()
+        {
+            // This result should saturate but we return a finite value.
+            return XFAIL;
+        }
+
         maybe_check_nan_bits(actual, expected, ctx)
     }
 
@@ -305,6 +316,7 @@ impl MaybeOverride<(i32, f32)> for SpecialCase {
         }
     }
 }
+
 impl MaybeOverride<(i32, f64)> for SpecialCase {
     fn check_float<F: Float>(
         input: (i32, f64),