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Re: speedup bootstrap
From: |
Peter O'Gorman |
Subject: |
Re: speedup bootstrap |
Date: |
Sun, 23 Oct 2005 23:17:41 +0900 |
User-agent: |
Mozilla Thunderbird 1.0.2 (Macintosh/20050317) |
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Ralf Wildenhues wrote:
| While working on the outstanding patch queue, I finally got fed up
| enough with CVS HEAD bootstrap and all the pizzas I had to eat each
| time, that it needed to be fixed. ;-)
|
| m4 tail recursion sucks performance-wise, if the argument lists are
| long, because: even if shift/m4_shiftn is fast(?), the whole stuff needs
| to be copied anyway for the new macro call.
|
| Just to make clear just how much of an issue this is: the code recurses
| as much as 600 C function calls deep (as seen by randomly interrupting
| m4 in a debugger; I haven't attempted to find the true maximum).
|
| So, let's do in some manual tail recursion elimination.
|
| OK to apply the combined patch below?
|
You know, I looked at sppeding up bootstrap for myself about a year ago, but
couldn't figure out the cause.
This is okay, even thouh I don't actually understand it :)
Peter
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- speedup bootstrap, Ralf Wildenhues, 2005/10/23
- Re: speedup bootstrap,
Peter O'Gorman <=