Dear All, The GCC source reference 4.8.1 will synthesized some of the double word operations(SI mode) like add /sub in the below case from the word size (HI) patterns,
(code snippet) expand_binop_directly function in the optabs.c. /* These can be done a word at a time by propagating carries. */ 1949 if ((binoptab == add_optab || binoptab == sub_optab) 1950 && mclass == MODE_INT 1951 && GET_MODE_SIZE (mode) >= 2 * UNITS_PER_WORD 1952 && optab_handler (binoptab, word_mode) != CODE_FOR_nothing) (code snippet) Current private target port will hash the above conditions ,hence compiler will synthesizes the double word operation w.r.t word operations . We would like prevent this optimisations ,The reason for the same is we do have the some optimised intrinsic functions ,which is coded in assemble and we want compiler to emit the intrinsic call to these routines instead of synthesizes the double word operations. Anyone in the group can shed some lights here will be appreciated . Thank you ~Umesh
