Re: [Open64-devel] Where can I find the simplifying codes?

[David S. <dls...@sg...>]

satan speed <sat...@ho...> wrote:

> the Pro64's gfec generate WHIRL tree:

>  LOC 1 4        x &= -1;
>   I4I4LDID 0 <2,1,x> T<4,.predef_I4,4>
>  I4STID 0 <2,1,x> T<4,.predef_I4,4>

> the WHIRL for "x &= -1" is not
>    I4I4LDID 0 <2,1,x> T<4,.predef_I4,4>
>    I4INTCONST -1
>   I4BAND
>  I4STID 0 <2,1,x> T<4,.predef_I4,4>
> 
> I think it must be simplified somewhere, but I can't find it.
> Who will tell me?

That would be the Simplifier.  In particular, look for the
procedure simp_band inside the file common/com/wn_simp_code.h.
simp_band includes the rule "j & -1 --> j".

The simplifier is invoked almost anytime that WHIRL code is
constructed.  In this case, gfec calls WN_Band, which is defined
as a marco in common/com/wn.h:

	#define WN_Band(type,l,r)  WN_Binary(OPR_BAND,type,l,r)

WN_Binary invokes WN_CreateExp2 (see common/com/wn.cxx for both),
which in turn invokes WN_SimplifyExp2, which invokes the
Simplifier, and eventually simp_band.

						- David