Proposal: readonly ref operators

[orthoxerox]

Problem

Structs are commonly used in game engines and standalone math libraries to store coordinates, transformation matrices and other similar values. Operators are the most convenient way to expose operations on these structs.

However, operators require that their parameters are passed by value. Copying large structs takes up to 40% of the execution time in microbenchmarks.

Solution

If #38 is implemented, readonly ref operators can be introduced. They are created by marking their parameters with in ref kind.

The following operators should be compiled into a void-returning method with 1 or 2 in parameters and one out parameter (this is faster than returning the result):

• unary +, -
• binary +, -, *, /, %, &, |, ^, <<, >>

The following methods should be compiled into a bool-returning method with 1 or 2 in parameters:

• unary true, false
• binary ==, !=, >, <, >=, <=

Open questions

Should it be possible to have one in parameter and one RefKind.None parameter for passing smaller value types or reference types?

[orthoxerox]

Works since 7.2. Kudos!