[Mesa-dev] [PATCH] st/mesa: fix incorrect loop over instruction src regs

[Keith Whitwell]

On Wed, 2011-08-17 at 09:36 -0500, Bryan Cain wrote:
> The usual commit message prefix for changes to glsl_to_tgsi is
> "glsl_to_tgsi", not "st/mesa".
> 
> On 08/16/2011 05:33 PM, Brian Paul wrote:
> > The array of src regs is of size 3, not 4.
> > ---
> >  src/mesa/state_tracker/st_glsl_to_tgsi.cpp |    2 +-
> >  1 files changed, 1 insertions(+), 1 deletions(-)
> >
> > diff --git a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > index aef23e7..7b90c81 100644
> > --- a/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > +++ b/src/mesa/state_tracker/st_glsl_to_tgsi.cpp
> > @@ -3443,7 +3443,7 @@ glsl_to_tgsi_visitor::eliminate_dead_code_advanced(void)
> >           /* Continuing the block, clear any channels from the write array that
> >            * are read by this instruction.
> >            */
> > -         for (int i = 0; i < 4; i++) {
> > +         for (unsigned i = 0; i < Elements(inst->src); i++) {
> 
> Why not just use 3 here?

Elements(inst->src) is self-documenting.  

3 is just a number and to figure out if it was the correct number you'd
have to go and look at the header file to see if it matched the value
there.

Both should generate the same compiled code.

Keith