On Wednesday, 14 January 2015 at 01:37:46 UTC, deadalnix wrote:
On Wednesday, 14 January 2015 at 00:24:41 UTC, Ola Fosheim
Grøstad wrote:
I don't see the problem. I'm suggesting value semantics, it
can be copied.
Then you can't catch by super class. This is not going to fly.
I said value. Use bitmasks. Class hierarchies don't work very
well.
You can't have chaining with this scheme...? But since you can
only have one instance it has to be initialized with value
semantics. It's a small constraint.
You write that paragraph like there is some logical links
between elements in it, but there is none.
If you cannot follow the logic... Where did you get lost?
The only things that is sure here is that it is going to make
the non exception path slower. Without specific we can say
anything else than that.
?
You essentially have two options:
1. A single branch on return.
2. Multiple return paths.
2a) returning to the calling function
2b) using a landing pad (current solution)
It won't help with register pressure. Having a pointer to an
exception object in a register is equivalent to having a
pointer to a TLS memory area in a register.
TLS is in a register already.
it can be optimized away so you don't need TLS if you don't
span over non-D code.
Without specifics, it is another instance of the sufficiently
smart compiler running gag.
This does not take a very smart compiler. You can use heuristics,
such as ones using the function signature.
You don't make things faster by making the calling convention
easier. There is chance that this is gonna fly any better than
a flat iron.
?
Of course you make it faster by allowing the compiler to use it's
own calling conventions.
