[Bug c/104209] New: ICE in lra_split_hard_reg_for, at lra-assigns.cc:1837

[gscfq@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104209

            Bug ID: 104209
           Summary: ICE in lra_split_hard_reg_for, at lra-assigns.cc:1837
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gscfq@t-online.de
  Target Milestone: ---

With file gcc.dg/torture/pr20314-2.c, 
affects versions down to at least r5 :


$ gcc-12-20220123 -c pr20314-2.c -m32 -fPIC
pr20314-2.c: In function 'f1':
pr20314-2.c:5:3: error: 'asm' operand has impossible constraints
    5 |   __asm__ volatile (""
      |   ^~~~~~~
pr20314-2.c:9:1: error: unable to find a register to spill
    9 | }
      | ^
pr20314-2.c:9:1: error: this is the insn:
(insn 96 94 98 2 (set (reg:SI 151 [123])
        (reg:SI 123)) "pr20314-2.c":5:3 81 {*movsi_internal}
     (expr_list:REG_DEAD (reg:SI 123)
        (nil)))
during RTL pass: reload
pr20314-2.c:9:1: internal compiler error: in lra_split_hard_reg_for, at
lra-assigns.cc:1837
0x685898 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        ../../gcc/rtl-error.cc:108
0xc1f9e1 lra_split_hard_reg_for()
        ../../gcc/lra-assigns.cc:1837
0xc19c5b lra(_IO_FILE*)
        ../../gcc/lra.cc:2420
0xbc7b39 do_reload
        ../../gcc/ira.cc:5940
0xbc7b39 execute
        ../../gcc/ira.cc:6126