From:	clc5q AT cobra DOT cs DOT Virginia DOT EDU (Clark L. Coleman)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Inline asm producing compile error
Date:	18 Jun 1999 18:24:34 GMT
Organization:	University of Virginia Computer Science Department
Lines:	23
Message-ID:	<7ke2t2$j3d$1@murdoch.acc.Virginia.EDU>
NNTP-Posting-Host:	cobra.cs.virginia.edu
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp
Reply-To:	djgpp AT delorie DOT com

I am getting "invalid asm: bad operand number", or something very
similar, out of the compiler (not assembler) for the following code:

bool FlushTLB(long address) {
   asm volatile("invlpg %1"
                : /* no outputs */
                : "m" (address));
   return TRUE;
}

Here is the idea:

INVLPG m

is documented as the x86 instruction to invalidate the TLB entry for
the memory page that contains address "m". My function accepts a
memory address as its parameter, and (unsuccessfully) attempts to use
inline assembler to produce an INVLPG instruction with that address.

Any help is appreciated.

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