[Bug target/12551] New: -O3 : internal compiler error: in clear_dead_regs, at regrename.c:137 or -O2 : internal compiler error: in sched_analyze_2, at sched-deps.c:757

["heinrich dot brand at fujitsu-siemens dot com" <gcc-bugzilla at gcc dot gnu dot org>]

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http://gcc.gnu.org/bugzilla/show_bug.cgi?id=12551

           Summary: -O3 : internal compiler error: in clear_dead_regs, at
                    regrename.c:137 or  -O2 : internal compiler error: in
                    sched_analyze_2, at sched-deps.c:757
           Product: gcc
           Version: 3.3.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P2
         Component: target
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: heinrich dot brand at fujitsu-siemens dot com
                CC: gcc-bugs at gcc dot gnu dot org
 GCC build triplet: s390-linux-gnu
  GCC host triplet: s390-linux-gnu
GCC target triplet: s390-linux-gnu

Interal error with gcc -c -O3 or -O2 and Source:


(Is not in gcc-3.2 on s390-linux-gnu.)




typedef struct {


  char *name;


  unsigned long long a:16;


  unsigned long long :7;


  unsigned long long b:24;


  unsigned long long (*f_fcn)(char *); 


  unsigned long long c:7;


  unsigned long long d:5;


  long long sum:61;


  long long e:3;


  char z;


} A;




typedef struct {


    long long a:31;


    long long b:31;


} B;




int foo(B sb, A s, long long b){


    s.a |= s.b;


    s.b |= s.c;


    s.d |= s.c;


    s.sum += s.a + s.b + s.c + s.d + sb.a + sb.b;


    return s.sum;


}


#######################################################################


The problem is a STM instruction. It reads




(insn 3 26 29 0 0 (parallel [


            (set (mem/s:SI (reg/f:SI 137) [3 S4 A32])


                (reg:SI 2 %r2))


            (set (mem/s:SI (plus:SI (reg/f:SI 137)


                        (const_int 4 [0x4])) [3 S4 A32])


                (reg:SI 3 %r3))


        ]) 69 {*store_multiple_si} (insn_list 176 (nil))


    (expr_list:REG_DEAD (reg:SI 3 %r3)


        (expr_list:REG_DEAD (reg:SI 2 %r2)


            (expr_list:REG_DEAD (reg/f:SI 137)


                (nil)))))




In the s390.md only part of the parallel is really given. It reads




(define_insn "*store_multiple_si"


  [(match_parallel 0 "store_multiple_operation"


                   [(set (match_operand:SI 1 "s_operand" "=Q")


                         (match_operand:SI 2 "register_operand" "r"))])]




When recognizing the instruction, the second set will not be put into a separate


operand field.




In the function eliminate_regs_in_insn the first use of reg 137 is seen and


replaced. The second use is not replaced. This causes an abort later.




One of the reasons is that 'insn_data[icode].operand[0].eliminable' is zero. So


elimination will not be done on the parallel as a whole, but only on operands


1 and 2.