[Bug target/83712] [6/7 Regression] "Unable to find a register to spill" when compiling for thumb1

[aoliva at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83712

Alexandre Oliva <aoliva at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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                 CC|                            |aoliva at gcc dot gnu.org

--- Comment #8 from Alexandre Oliva <aoliva at gcc dot gnu.org> ---
Hey, Vlad, I'm afraid bisection tells me r258390 caused a regression I'm seeing
on i686-linux-gnu.  hsa-regalloc now fails to compile in stage2:

../../gcc/hsa-regalloc.c: In function ‘void hsa_regalloc()’:
../../gcc/hsa-regalloc.c:728:1: error: unable to find a register to spill
 }
 ^
../../gcc/hsa-regalloc.c:728:1: error: this is the insn:
(insn 1513 3740 3741 249 (parallel [
            (set (reg/v:SI 1258 [orig:435 ret ] [435])
                (div:SI (reg/v:SI 1258 [orig:435 ret ] [435])
                    (reg:SI 1162)))
            (set (reg:SI 1280 [709])
                (mod:SI (reg/v:SI 1258 [orig:435 ret ] [435])
                    (reg:SI 1162)))
            (clobber (reg:CC 17 flags))
        ]) "../../gcc/hsa-regalloc.c":305 312 {*divmodsi4}
     (expr_list:REG_UNUSED (reg:SI 1280 [709])
        (expr_list:REG_DEAD (reg:SI 1162)
            (expr_list:REG_UNUSED (reg:CC 17 flags)
                (nil)))))
during RTL pass: reload
../../gcc/hsa-regalloc.c:728:1: internal compiler error: in
lra_split_hard_reg_for, at lra-assigns.c:1802
0x8c4e069 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        ../../gcc/rtl-error.c:108
0x8aef4e2 lra_split_hard_reg_for()
        ../../gcc/lra-assigns.c:1802
0x8ae909a lra(_IO_FILE*)
        ../../gcc/lra.c:2506
0x8a9cce7 do_reload
        ../../gcc/ira.c:5465
0x8a9d17a execute
        ../../gcc/ira.c:5649
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <https://gcc.gnu.org/bugs/> for instructions.
Makefile:1110: recipe for target 'hsa-regalloc.o' failed