https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66768
--- Comment #9 from rguenther at suse dot de <rguenther at suse dot de> --- On Tue, 7 Jul 2015, amker at gcc dot gnu.org wrote: > https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66768 > > --- Comment #8 from amker at gcc dot gnu.org --- > So address space info is kept and checked in base object's type of MEM_REF. > As > in function expand_expr_real_1: > > case TARGET_MEM_REF: > { > addr_space_t as > = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0)))); > enum insn_code icode; > unsigned int align; > > The AVR ICE happens when base of MEM_REF[base:0, index:(sizetype)ivtmp] has > __memx address space attribute. Since pointer to memory object in __memx > address space (PSImode) has 24 bits type length, while the type of index is > sizetype(Pmode == HImode in this case), which has 16 bits type length. The > expression "(sizetype)ivtmp" is expanded into (subreg:HI (reg:PSI 40) 0). > > So I still think IVO should distribute ivtmp as base part of MEM_REF since it > stands for a memory object. Otherwise, we have below IVOed code: > > <bb 3>: > # total_10 = PHI <total_5(4), 0(2)> > # ivtmp.7_8 = PHI <ivtmp.7_7(4), 4660(2)> > _12 = (sizetype) ivtmp.7_8; > _4 = MEM[base: 0B, index: _12, offset: 0B]; > total_5 = _4 + total_10; > ivtmp.7_7 = ivtmp.7_8 + 2; > if (ivtmp.7_7 != 4700) > goto <bb 4>; > else > goto <bb 5>; > > <bb 4>: > goto <bb 3>; > > > This is wrong since truncation of ivtmp.7_8 to sizetype could result in wrong > address. Indeed truncating it to sizetype just to make it fit into INDEX looks wrong (extension is ok, truncation is not).
