Supporting 'MAC' instruction on gcc v4.1.1

[Rask Ingemann Lambertsen]

On Wed, May 16, 2007 at 11:16:59AM +0530, Rahul wrote:

> But for -O0 optimization, even the 'progname.c.*.combine file' is
> *not* getting generated for '-fdump-rtl-all / -fdump-rtl-combine'
> options.

   The *.combine dumpfile is generated when the combine pass runs.

> Please tell me whether the combining of related instructions, by the
> combiner, will be taking place only when optimization is enabled?

   Combination of instructions is an optimization and needs at least -O1.

> if
> that is the case, is there any way to make gcc recognize the 'MAC"
> pattern for  -O0 optimisation?

   It would be entirely possible to add an option such as
-fcombine-instructions to enable the life1 and combine passes separately.

-- 
Rask Ingemann Lambertsen