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From: "Bruce Ellis" <brucee@chunder.com>
To: <9fans@cse.psu.edu>
Subject: Re: [9fans] remember when C compiler used to produce working code? i don't!
Date: Sat, 31 Jan 2004 12:51:00 +1100	[thread overview]
Message-ID: <029701c3e79d$8af35370$8201a8c0@cc77109e> (raw)
In-Reply-To: <027401c3e796$68040370$8201a8c0@cc77109e>

on further inspection (and coffee) i would suggest that the
"sametype" test be changed so that in these cases the OCAST
is not inserted for <integral> asop <floating>.

the onus would then be on the individual compilers to handle
asops of this form, further complicating the asop code at
e.g. 8c/cgen.c:434 - what a tedious solution.

the reasoning (which may not be right) is that the port code
in cc cannot, in general, rewrite the tree; consider:

    *lp++ *= ratio;

8c/cgen.c uses reglcgen() for the hard lhs.

the other compilers have logically similar code to do this,
though most have more registers, so it's easier.

comments anyone?

brucee
----- Original Message -----
From: "Bruce Ellis" <brucee@chunder.com>
To: <9fans@cse.psu.edu>
Sent: Saturday, January 31, 2004 11:57 AM
Subject: Re: [9fans] remember when C compiler used to produce working code? i don't!


> indeed.  the expression is being rewritten as
>
>     elasticity *= (long)ratio;
>
> com.c:196
>
> same thing for + and - at line 169.
>
> brucee
> ----- Original Message -----
> From: "David Presotto" <presotto@closedmind.org>
> To: <9fans@cse.psu.edu>
> Sent: Saturday, January 31, 2004 9:40 AM
> Subject: Re: [9fans] remember when C compiler used to produce working code? i don't!
>
>
> > Looks like a problem in cc/com.c in tcomo().  I'm going to be away
> > for a week and will take a crack at it when I get back.  If someone
> > else wants to try in the mean time...
>


  parent reply	other threads:[~2004-01-31  1:51 UTC|newest]

Thread overview: 17+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-01-30 22:05 andrey mirtchovski
2004-01-30 22:29 ` David Presotto
2004-01-30 22:40   ` David Presotto
2004-01-31  0:57     ` Bruce Ellis
2004-01-31  1:34       ` boyd, rounin
2004-01-31  1:51       ` Bruce Ellis [this message]
2004-01-31  2:15         ` boyd, rounin
2004-01-31  3:13         ` David Presotto
2004-01-31  7:40           ` Bruce Ellis
2004-01-31  9:03             ` andrey mirtchovski
2004-01-31 10:08               ` David Tolpin
2004-01-31 14:19               ` boyd, rounin
2004-01-31 14:57                 ` Bruce Ellis
2004-01-31 17:59             ` Scott Schwartz
2004-01-31 19:23               ` Rob Pike
2004-01-31 19:59                 ` Bruce Ellis
2004-01-31 20:42                 ` Charles Forsyth

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