On Wednesday, 17 December 2014 at 11:39:43 UTC, Foo wrote:
On Wednesday, 17 December 2014 at 10:59:09 UTC, bearophile
wrote:
Foo:
Hi,
Could someone explain me, if and how it is possible to
allocate a variable length array with inline assembly?
Somewhat like
----
int[] arr;
int n = 42;
asm {
// allocate n stack space for arr
}
----
I know it is dangerous and all that, but I just want it know.
;)
Doing it with alloca is simpler:
void main() @nogc {
import core.stdc.stdlib: alloca, exit;
alias T = int;
enum n = 42;
auto ptr = cast(T*)alloca(T.sizeof * n);
if (ptr == null)
exit(1); // Or throw a memory error.
auto arr = ptr[0 .. n];
}
Bye,
bearophile
Yes I know, but I really want it in inline assembly. It's for
learning purpose. :)
You could look at the disassembly.
