Optimise min/max

Swapping the conditions generates more efficient x86 assembly. See
#46926 (comment).

Author: varkor

src/libcore/num/f32.rs

@@ -263,7 +263,7 @@ impl Float for f32 {
         // 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 self < other || self.is_nan() { other } else { self }) * 1.0
+        (if self.is_nan() || self < other { other } else { self }) * 1.0
     }
 
     /// Returns the minimum of the two numbers.
@@ -277,6 +277,6 @@ impl Float for f32 {
         // 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 self < other || other.is_nan() { self } else { other }) * 1.0
+        (if other.is_nan() || self < other { self } else { other }) * 1.0
     }
 }

src/libcore/num/f64.rs

@@ -261,7 +261,7 @@ impl Float for f64 {
         // 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 self < other || self.is_nan() { other } else { self }) * 1.0
+        (if self.is_nan() || self < other { other } else { self }) * 1.0
     }
 
     /// Returns the minimum of the two numbers.
@@ -275,6 +275,6 @@ impl Float for f64 {
         // 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 self < other || other.is_nan() { self } else { other }) * 1.0
+        (if other.is_nan() || self < other { self } else { other }) * 1.0
     }
 }