The accompanying patch handles a bug in backtracing through glibc's sleep.
The compiler generates some predicated insns prior to saving the return register
b0 into a register stack register.  The current code stops when it sees a
predicated insn.  The change makes the prologue examination stop only if the
function is frameless or we have already seen the return register.

This removes a number of failures in gdb.threads caused when we catch another
thread in sleep and we try and backtrace.

Ok to commit?

-- Jeff J.

2003-08-26  Jeff Johnston  <jjohnstn@redhat.com>

	* ia64-tdep.c (examine_prologue): Only stop at predicated insns if
	we are frameless or the return address register is already known.