From: cbramix AT libero DOT it (Carlo)
Newsgroups: comp.os.msdos.djgpp
Subject: Optimizing 8 bit variables?
Date: 26 Aug 2003 05:27:43 -0700
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To: djgpp AT delorie DOT com
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Hello everyone!
I have this little problem: GCC doesn't seem to optimize very well a
piece of code I wrote with 8 bit variables.
So, I was thinking to use a local register variable.
On the documentation I read that GCC can do that:

register int *foo asm ("ebx");

But what should I do if I need to use BH or BL registers?
I tried to use BH or BL instead of ebx:

register unsigned char myvar asm ("bl");

GCC doesn't give me error messages, but it generates the same code I
got without the 'asm' keyword.

Thanks in advance.

Carlo.