On 2021-01-11 01:01 +0800, Xi Ruoyao wrote: > Hi Jeff and Jakub, > > On 2021-01-04 14:19 -0700, Jeff Law wrote: > > On 1/4/21 2:00 PM, Jakub Jelinek wrote: > > > On Mon, Jan 04, 2021 at 01:51:59PM -0700, Jeff Law via Gcc-patches wrote: > > > > > Sorry, I forgot to include the ChangeLog: > > > > > > > > > > gcc/ChangeLog: > > > > > > > > > > 2020-12-31 Xi Ruoyao <xry...@mengyan1223.wang> > > > > > > > > > > PR target/98491 > > > > > * config/mips/mips.c (mips_symbol_insns): Do not use > > > > > MSA_SUPPORTED_MODE_P if mode is MAX_MACHINE_MODE. > > > > So I absolutely agree the current code is wrong as it does an out of > > > > bounds array access. > > > > > > > > > > > > Would it be better to instead to change MSA_SUPPORTED_MODE_P to evaluate > > > > to zero if MODE is MAX_MACHINE_MODE? That would protect all the uses of > > > > MSA_SUPPORTED_MODE_P. Something like this perhaps? > > > But MAX_MACHINE_MODE is the one past last valid mode, I'm not aware of > > > any target that would protect all macros that deal with modes that way. > > > > > > So, perhaps best would be stop using the MAX_MACHINE_MODE as magic value > > > for that function and instead use say VOIDmode that shouldn't normally > > > appear either? > > I think we have to allow VOIDmode because constants don't necessarily > > have modes. And I certainly agree that using MAX_MACHINE_MODE like > > this is ugly and error prone (as we can see from the BZ). > > > > I also couldn't convince myself that the code and comments were actually > > consistent, particularly for MSA targets which the comment claims can > > never handle constants for ld/st (and thus should be returning 0 for > > MAX_MACHINE_MODE). Though maybe mips_symbol_insns_1 ultimately handles > > that correctly. > > > > > > > > > > But I don't really see anything wrong on the mips_symbol_insns above > > > change either. > > Me neither. I'm just questioning if bullet-proofing in the > > MSA_SUPPORTED_MODE_P would be a better option. While I've worked in the > > MIPS port in the past, I don't really have any significannt experience > > with the MSA support. > > I can't understand the comment either. To me it looks like it's possible to > remove this "if (MSA_SUPPORTED_P (mode)) return 0;" > > CC Robert to get some help.
Happy new lunar year folks. I found a newer email address of Robert. Hope it is still being used. Could someone update MAINTAINERS file by the way? -- Xi Ruoyao <xry...@mengyan1223.wang> School of Aerospace Science and Technology, Xidian University
