[Bug c/121235] Local register variable constraints aren't respected in extended asm

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=121235

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
In fact my fixed up code is how it is written in the documentation even.

int t1 = …;
register int *p1 asm ("r0") = …;
register int *p2 asm ("r1") = t1;
register int *result asm ("r0");
asm ("sysint" : "=r" (result) : "0" (p1), "r" (p2));


Notice the use of p1/p2 in the inline-asm rather than t1.