Interesting code in exec_setregs
David Xu
davidxu at freebsd.org
Sat Sep 25 22:40:28 PDT 2004
I found following code in sys/i386/i386/machdep.c:
function exec_setregs:
bzero((char *)regs, sizeof(struct trapframe));
regs->tf_eip = entry;
regs->tf_esp = stack;
regs->tf_eflags = PSL_USER | (regs->tf_eflags & PSL_T);
the regs is cleared to zero, why do we bother to test it
again ? regs->tf_eflags & PSL_T is useless code.
AMD64 also has this, I also found it in releng_4, why ?
David Xu
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