Update library/core/src/primitive_docs.rs

Co-authored-by: Ralf Jung <[email protected]>

Author: calder

library/core/src/primitive_docs.rs

@@ -1320,8 +1320,11 @@ mod prim_f16 {}
 ///
 /// # Algebraic operators
 ///
-/// Algebraic operators of the form `a.algebraic_*(b)` allow the compiler to reassociate individual
-/// floating point operations for better vectorization. The exact set of optimizations is
+/// Algebraic operators of the form `a.algebraic_*(b)` allow the compiler to optimize
+/// floating point operations using all the usual algebraic properties of real numbers --
+/// despite the fact that those properties do *not* hold on floating point numbers.
+/// This can give a great performance boost since it may unlock vectorization.
+/// The exact set of optimizations is
 /// unspecified but typically allows combining operations, rearranging series of operations based
 /// on mathematical properties, converting between division and reciprocal multiplication, and
 /// disregarding the sign of zero. This means that the results of elementary operations may have