Re: [Bug-zile] Incremental search is dog slow in moderately-sized files

[Gary V. Vaughan]

Hi Reuben,

On Jan 21, 2014, at 12:10 PM, Reuben Thomas <address@hidden> wrote:

> On 20 January 2014 23:07, Gary V. Vaughan <address@hidden> wrote:
>> Thanks for taking a look at this.
>> 
>> On Jan 21, 2014, at 4:07 AM, Reuben Thomas <address@hidden> wrote:
>> >
>> > I've run out of time for [[debugging the alien.default.memrchr crashes on 
>> > glib]] for now. However, I have an idea: how about adding asserts to your 
>> > Lua memrchr to check for out-of-bound accesses? I can't see anything wrong 
>> > with memrchr itself now, so I suspect bad arguments which merely result in 
>> > nil results in the Lua version.
>> 
>> I've noticed that about half the time, a random one out of the 100+ 
>> run-lisp-tests.lua checks (`make tests-check-local`) crashes zmacs using my 
>> Lua memrchr too.  Instrumenting shows that my memrchr returns the location 
>> of EOL prior to the one returned by find_substr().  Naïvely changing memrchr 
>> to start the search one byte higher in memory breaks everything though, so I 
>> need to spend some time understanding the details of find_substr, and either 
>> fix that and whatever changes ripple out from there, or make sure memrchr is 
>> interface compatible before swapping it out.  At least I have a way of 
>> pinning it down now... and then I can make the same changes in the 
>> alien.default.memrchr wrapper and hope that works too.
> 
> When I was translating all this stuff from C to Lua it was almost always an 
> off-by-one bug in these cases. It's possible I may have left some in the Zile 
> code myself!

I spotted many of those fixes in the gitlog.  However, since there is no 
0-based indexing anywhere in Lua Zile, I guess these are purely artifacts of 
the C->Lua transition, right?  And yet there's a ton of +1 and -1 adjustments 
scattered around that I don't fully understand yet. Or are Zile buffers 
0-based, and have to be adjusted to Lua 1-based indices?  If so, then I might 
try and go for a clean slate by making everything 1-based, except when 
accepting or displaying buffer indices in the zlisp Defuns...

Thoughts?

Cheers,
-- 
Gary V. Vaughan (gary AT gnu DOT org)

signature.asc
Description: Message signed with OpenPGP using GPGMail