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.