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Newsgroups: | comp.os.msdos.djgpp |
From: | Elliott Oti <e DOT oti AT stud DOT warande DOT ruu DOT nl> |
Subject: | Re: Disabling use of registers |
Sender: | usenet AT fys DOT ruu DOT nl (News system Tijgertje) |
Message-ID: | <34651599.3CBA@stud.warande.ruu.nl> |
Date: | Sun, 9 Nov 1997 01:44:57 GMT |
References: | <O6EQDcF78GA DOT 198 AT upnetnews03> |
Mime-Version: | 1.0 |
Organization: | Bipolar Widgets International |
Lines: | 16 |
To: | djgpp AT delorie DOT com |
DJ-Gateway: | from newsgroup comp.os.msdos.djgpp |
Carolyn Kelly-Pajot wrote: > > Is there a way of making GCC not use a certain register? I'm trying to use some > registers to speed up code, and want to make sure they are not used by the rest > of my code. Not as far as I know. But what's the problem? The 386 has only six general registers ( seven, if you count %ebp ), and that is not much; denying gcc the use of a register is likely to make the code slower. If your concern is that inline code tends to get mangled by the optimiser, try declaring your inline assembler code as asm volatile instead of plain asm. -- ------------ Elliott Oti --------------- ------------- http://www.fys.ruu.nl/~oti ---------
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