Message-Id: <m0xlZKT-000S29C@inti.gov.ar>
Comments: Authenticated sender is <salvador AT natacha DOT inti DOT gov DOT ar>
From: "Salvador Eduardo Tropea (SET)" <salvador AT inti DOT gov DOT ar>
Organization: INTI
To: "DeHackEd" <dehacked72 AT nospam DOT hotmail DOT com>, djgpp AT delorie DOT com
Date: Fri, 26 Dec 1997 16:03:22 +0000
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Subject: Re: Optmization and Exceptions
In-reply-to: <OG5YUSZE9GA.170@upnetnews04>
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"DeHackEd" <dehacked72 AT nospam DOT hotmail DOT com> wrote:

> I was just playing around with the C++ compiler and I noticed a few things:
> 
> 1) Without optmizations, strlen("string literal") evaluates to asm
> LC1:
>     .ascii "string literal\0"
> 
> pushl $LC1
> call _strlen
> 
> But with -O3, it just evaluates to $14 (I think - I can't count).
And what's the problem! that's what you want! optimized code!
strlen is inline and GCC with -O3 is good enough to evaluate the operation in 
compile time.

> 2) With or without optmizations, (12*5) evaluates to $60, not a long asm output
> for calculating it. This is something which came up as a problem on some
> newsgroup.
GCC EVER optimizes multiplications. GCC simply doesn't use mul in i386 platform 
if one of the values is known at compile time. That's very good. It generates 
better code than a lot of assembler programmers! 

I don't understand very well, are you showing the good things you found? We can 
saturate the list with it ;-))

SET 
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