On Sunday, 18 July 2021 at 16:32:46 UTC, Basile B. wrote:
Yeah I can confirm it's aweful. Took me hours to understand how
to use it a bit (my PL has [an
interface](https://styx-lang.gitlab.io/styx/primary_expressions.html#asmexpression) for LLVM asm)
You need to add a "x" to the constraint string
return __asm!int4("paddd $1,$0","=x,x,x",a, b);
- **=x** says "returns in whatever is has to"
- **x** (1) is the constraint for input `a`, which is passed as
operand **$0**
- **x** (2) is the constraint for input `b`, which is passed as
operand **$1**
So the thing to get is that the output constraint does not
consume anything else, it is standalone.
Thanks.
Indeed that seems to work even when inline and optimized.
Registers are spilled to stack.
A minor concern is what happens when the enclosing function is
extern(C) => https://d.godbolt.org/z/s6dM3a3de
I need to check that more...
