323 #define Sglext_setzero(valA,valB)	\  argument
324     Sextallp1(valA) = 0; Sextallp2(valB) = 0
330 #define Sglext_iszero(valA,valB) (Sextallp1(valA)==0 && Sextallp2(valB)==0)  argument
393 #define Sglext_leftshiftby8(valA,valB) \  argument
394     Shiftdouble(Sextallp1(valA),Sextallp2(valB),24,Sextallp1(valA)); \
396 #define Sglext_leftshiftby4(valA,valB) \  argument
397     Shiftdouble(Sextallp1(valA),Sextallp2(valB),28,Sextallp1(valA)); \
399 #define Sglext_leftshiftby3(valA,valB) \  argument
400     Shiftdouble(Sextallp1(valA),Sextallp2(valB),29,Sextallp1(valA)); \
402 #define Sglext_leftshiftby2(valA,valB) \  argument
403     Shiftdouble(Sextallp1(valA),Sextallp2(valB),30,Sextallp1(valA)); \
405 #define Sglext_leftshiftby1(valA,valB) \  argument
406     Shiftdouble(Sextallp1(valA),Sextallp2(valB),31,Sextallp1(valA)); \