Subject: exception returns in locore_mips3.S
To: None <port-mips@netbsd.org>
From: Toru Nishimura <nisimura@itc.aist-nara.ac.jp>
List: port-mips
Date: 10/03/2000 10:14:35
Folks,

I was puzzled a bit with exception return codes in locore_mips3.S

I think exception returns can be done in following steps,

	- restore SR value on exception time with mtc0 insn.
	- because it has EXL bit, MIPS3 processor now blocks interrupts
	  and enters critical section to restore the register values when
	  exception was taken.

Code paths found in locore_mips3.S are somehow inconsistent each
others and looks redundant.  I remember it used to be as simple as
mentioned above.  I wonder why they are done in such ways, and whether
it's possible to make locore_mips3.S simple.

Tohru Nishimura