c-lineup-gcc-asm-reg is a compiled Lisp function in `cc-align.el'.

(c-lineup-gcc-asm-reg ELEM)

Line up a gcc asm register under one on a previous line.

asm ("foo %1, %0\n"
"bar %0, %1"
: "=r" (w),
"=r" (x)
: "0" (y),
"1" (z));

The "x" line is aligned to the text after the ":" on the "w" line, and
similarly "z" under "y".

This is done only in an "asm" or "__asm__" block, and only to
those lines mentioned. Anywhere else nil is returned. The usual
arrangement is to have this routine as an extra feature at the start
of arglist line-ups, e.g.

(c-lineup-gcc-asm-reg c-lineup-arglist)

Works with: arglist-cont, arglist-cont-nonempty.