[Bug rtl-optimization/113098] New: [14 Regression] LRA ICE building glibc for mips

[Bug rtl-optimization/113098] New: [14 Regression] LRA ICE building glibc for mips

[jsm28 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113098

            Bug ID: 113098
           Summary: [14 Regression] LRA ICE building glibc for mips
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: rtl-optimization
          Assignee: unassigned at gcc dot gnu.org
          Reporter: jsm28 at gcc dot gnu.org
  Target Milestone: ---
            Target: mips*-*-*

Created attachment 56912
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=56912&action=edit
preprocessed source

Compile the attached code, from glibc, with -mabi=32 -O2 for MIPS (I used a
mips64-linux-gnu compiler configured --with-mips-plt --with-nan=2008
--with-arch-64=mips64r2 --with-arch-32=mips32r2; the --with-arch-32 part may
well be required to reproduce the issue).

offtime.c: In function '__offtime':
offtime.c:86:1: error: unable to find a register to spill
offtime.c:86:1: error: this is the insn:
(insn 1015 3973 3974 24 (parallel [
            (set (reg:SI 2971)
                (plus:SI (mult:SI (reg:SI 2367)
                        (reg:SI 898))
                    (reg:SI 2972)))
            (clobber (reg:SI 2881 [2814]))
            (clobber (reg:SI 2815))
        ]) "offtime.c":67:84 42 {*mul_acc_si}
     (expr_list:REG_UNUSED (reg:SI 2815)
        (expr_list:REG_UNUSED (reg:SI 2881 [2814])
            (expr_list:REG_DEAD (reg:SI 2972)
                (expr_list:REG_DEAD (reg:SI 2367)
                    (expr_list:REG_DEAD (reg:SI 898)
                        (nil)))))))
during RTL pass: reload
offtime.c:86:1: internal compiler error: in lra_split_hard_reg_for, at
lra-assigns.cc:1862
0x6f3f05 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        /scratch/jmyers/glibc/many14/src/gcc/gcc/rtl-error.cc:108
0xd53048 lra_split_hard_reg_for()
        /scratch/jmyers/glibc/many14/src/gcc/gcc/lra-assigns.cc:1862
0xd4c9c9 lra(_IO_FILE*, int)
        /scratch/jmyers/glibc/many14/src/gcc/gcc/lra.cc:2518
0xd00d97 do_reload
        /scratch/jmyers/glibc/many14/src/gcc/gcc/ira.cc:5973
0xd00d97 execute
        /scratch/jmyers/glibc/many14/src/gcc/gcc/ira.cc:6161
Please submit a full bug report, with preprocessed source (by using
-freport-bug).
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.

ICE introduced by

commit 989e67f827b74b76e58abe137ce12d948af2290c
Author: Vladimir N. Makarov <vmakarov@redhat.com>
Date:   Mon Dec 18 17:12:23 2023 -0500

    [PR112918][LRA]: Fixing IRA ICE on m68k

    Some GCC tests on m68K port of LRA is failed on `maximum number of
    generated reload insns per insn achieved`.  The problem is in that for
    subreg reload LRA can not narrow reg class more from ALL_REGS to
    GENERAL_REGS and then to data regs or address regs.  The patch permits
    narowing reg class from reload insns if this results in succesful
    matching of reg operand.

[Bug rtl-optimization/113098] [14 Regression] LRA ICE building glibc for mips

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113098

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |14.0

[Bug rtl-optimization/113098] [14 Regression] LRA ICE building glibc for mips

[vmakarov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113098

--- Comment #1 from Vladimir Makarov <vmakarov at gcc dot gnu.org> ---
The patch causing this was reverted.

[Bug rtl-optimization/113098] [14 Regression] LRA ICE building glibc for mips

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113098

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Patch was reverted so fixed.

[Bug rtl-optimization/113098] [14 Regression] LRA ICE building glibc for mips

[jsm28 at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113098

Joseph S. Myers <jsm28 at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|RESOLVED                    |REOPENED
   Last reconfirmed|                            |2024-01-12
         Resolution|FIXED                       |---
     Ever confirmed|0                           |1

--- Comment #3 from Joseph S. Myers <jsm28 at gcc dot gnu.org> ---
This ICE building glibc has come back with the new fix for bug 112918 (not
bisected, just presuming that commit is the cause, but it seems very likely).

Note: the arc ICE observed with the previous reverted fix for bug 112918 (bug
113097) has *not* come back.

[Bug rtl-optimization/113098] [14 Regression] LRA ICE building glibc for mips

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113098

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|REOPENED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #4 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Note it was already filed as PR 113354.