чт, 14 нояб. 2024 г. в 23:10, Vladimir Makarov <vmaka...@redhat.com>: > > > On 11/13/24 14:10, Denis Chertykov wrote: > > The fix for PR117191 > > > > Wrong code appears after dse2 pass because it removes necessary insns. > > (ie insn 554 - store to frame spill slot) > > This happened because LRA pass doesn't cleanup the code exactly like > > reload does. > > The reload1.c has a special pass for such cleanup. > > The reload removes CLOBBER insns with spill slots like this: > > (insn 202 184 186 7 (clobber (mem/c:TI (plus:HI (reg/f:HI 28 r28) > > (const_int 1 [0x1])) [3 %sfp+1 S16 A8])) -1 > > (nil)) > > > I guess not all functionality of reload was implemented (e.g. support > for architecture with address in the memory address like vax). The same > happened with removing such clobbers. Implementation of LRA was a > process of simplification and finding what minimal functionality would work. > > > > > > > LRA have a similar place where it removes unnecessary insns, but not > > CLOBBER insns with > > memory spill slots. It's `lra_final_code_change' function. > > > > I just mark a CLOBBER insn with pseudo spilled to memory for removing > > it later together > > with LRA temporary CLOBBER insns. > > > > The patch is simple. > > On x86_64, it bootstraps+regtests fine. > > Ok for trunk? > > > > > Special clobbers with BLK mode can not be here and moreover memory for > spilled pseudo can not get BLK mode. So I think the patch is safe. > > The patch is OK for me. Thank you for working on this issue.
committed fe1486e118d Denis.
