https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109457
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |RESOLVED
Resolution|--- |INVALID
--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
This has nothing to do with [x] but rather the constraint g and z operand
modifier.
The g constraint is defined as:
Any register, memory or immediate integer operand is allowed, except for
registers that are not general registers.
So constant 1 will be allowed here.
While the modifier z says:
z Print the opcode suffix for the size of the current integer operand
(one of b/w/l/q). %z0 l
Note integer constants don't have a size ...
This is the corrected inline-asm:
template<class T>
inline T onec_add(T a, T b)
{
asm( "add%z[a]\t%[b], %[a]"
"\n\tadc%z[a]\t$0, %[a]"
: [a]"+g"(a) // inputs
: [b]"g"(b) // outputs
: "cc" // clobbers
);
return a;
}
Note I see you did the replacement of [a] and [b] in your example but when you
replaced %z[b], you replaced it with %z0 rather than what it was originally
which was %z1.
