Add maxf

Author: varkor

CHANGELOG.md

@@ -9,6 +9,7 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 
 - minf
 - min
+- maxf
 
 ## [v0.1.2] - 2018-07-18
 

src/lib.rs

@@ -138,6 +138,8 @@ pub trait F32Ext: private::Sealed + Sized {
     fn atanh(self) -> Self;
 
     fn min(self, other: Self) -> Self;
+
+    fn max(self, other: Self) -> Self;
 }
 
 impl F32Ext for f32 {
@@ -334,6 +336,11 @@ impl F32Ext for f32 {
     fn min(self, other: Self) -> Self {
         minf(self, other)
     }
+
+    #[inline]
+    fn max(self, other: Self) -> Self {
+        maxf(self, other)
+    }
 }
 
 /// Math support for `f64`

src/math/maxf.rs

@@ -0,0 +1,13 @@
+#[inline]
+#[cfg_attr(all(test, assert_no_panic), no_panic::no_panic)]
+pub fn maxf(x: f32, y: f32) -> f32 {
+    // IEEE754 says: maxNum(x, y) is the canonicalized number y if x < y, x if y < x, the
+    // canonicalized number if one operand is a number and the other a quiet NaN. Otherwise it
+    // is either x or y, canonicalized (this means results might differ among implementations).
+    // When either x or y is a signalingNaN, then the result is according to 6.2.
+    //
+    // Since we do not support sNaN in Rust yet, we do not need to handle them.
+    // FIXME(nagisa): due to https://bugs.llvm.org/show_bug.cgi?id=33303 we canonicalize by
+    // multiplying by 1.0. Should switch to the `canonicalize` when it works.
+    (if x.is_nan() || x < y { y } else { x }) * 1.0
+}

src/math/mod.rs

@@ -168,6 +168,7 @@ mod trunc;
 mod truncf;
 mod min;
 mod minf;
+mod maxf;
 
 // Use separated imports instead of {}-grouped imports for easier merging.
 pub use self::acos::acos;
@@ -276,6 +277,7 @@ pub use self::trunc::trunc;
 pub use self::truncf::truncf;
 pub use self::min::min;
 pub use self::minf::minf;
+pub use self::maxf::maxf;
 
 // Private modules
 mod expo2;