[cfe-dev] feasibility of C++ to inline-assembly using clang

[David Tweed]

On Mon, Mar 15, 2010 at 5:14 AM, David Tweed <david.tweed at gmail.com> wrote:
> On Mon, Mar 15, 2010 at 4:48 AM, Eli Friedman <eli.friedman at gmail.com> wrote:
> my
> understandnig was that NaCl requires inserting NOP padding at various
> points to ensure that you can't generate dangerous instructions by
> jumping into the middle of an instruction, modifying the calling
> convention and prohibiting certain dangerous instructions that I
> didn't think ordinary computation would result in anyway.

Just to correct something I misremembered from when I read the
NativeClient paper: it seem what happens is that certain kinds of
jumps (not the kind used in, eg, a do{ } while()" loop that might
occur in numeric code) are forced to be to addresses that are
multiples of 32 (which pesumably requires strategic insertion of NOPs)

-- 
cheers, dave tweed__________________________
computer vision reasearcher: david.tweed at gmail.com
"while having code so boring anyone can maintain it, use Python." --
attempted insult seen on slashdot