define_reservation regexp duplicated in pentium.md for two different reservation names

define_reservation regexp duplicated in pentium.md for two different reservation names

[Jonah B Graham]

I was just looking at the pentium.md file to learn about the DFA scheduler when I saw this code:

(define_reservation "pentium-firstuboth" "(pentium-load + pentium-firstu
					   + pentium-memory)")
(define_reservation "pentium-firstvboth" "(pentium-load + pentium-firstu
					   + pentium-memory)")

Note that both define_reservations are the same value. I assume that the second one was supposed to be:

(define_reservation "pentium-firstvboth" "(pentium-load + pentium-firstv
					   + pentium-memory)")

But I don't know enough about the pentium pipeline to know whether that is the correct definition. 

The version of the file I was looking at was Revision 1.1.8.1 on the subversions web site.

Jonah

Re: define_reservation regexp duplicated in pentium.md for two different reservation names

[Jeff Law]

In message <200207170832.g6H8Wbb27874@mars.drw.net>, Jonah B Graham writes:
 >I was just looking at the pentium.md file to learn about the DFA scheduler wh
 >en I saw this code:
 >
 >(define_reservation "pentium-firstuboth" "(pentium-load + pentium-firstu
 >					   + pentium-memory)")
 >(define_reservation "pentium-firstvboth" "(pentium-load + pentium-firstu
 >					   + pentium-memory)")
 >
 >Note that both define_reservations are the same value. I assume that the seco
 >nd one was supposed to be:
[ ... ]
I'd noticed this when testing/benchmarking Jan's DFA description for the
pentium processors a few months ago.  I thought I had fixed it, but obviously
I didn't.

Anyway, I've yet to find any code effected by this fix -- the set of 
circumstances where we need that reservation are extremely rare, maybe
even impossible (call/branch with a read-modify-write operand). 

Anyway, I'll install the fix shortly.

jeff