tag	line	file	source code
rdusp	99	arch/alpha/kernel/process.c	usp = rdusp();
rdusp	316	arch/alpha/kernel/signal.c	frame = (struct sigcontext_struct *) rdusp();
rdusp	218	arch/alpha/kernel/traps.c	usp = rdusp();
rdusp	37	include/asm-alpha/system.h	extern unsigned long rdusp(void);