[Bug c/79514] New: ICE in curr_insn_transform, at lra-constraints.c:3773

[gerhard.steinmetz.fortran@t-online.de]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79514

            Bug ID: 79514
           Summary: ICE in curr_insn_transform, at lra-constraints.c:3773
           Product: gcc
           Version: 7.0.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gerhard.steinmetz.fortran@t-online.de
  Target Milestone: ---

A test run with -m96bit-long-double (on x86_64 GNU/Linux)
gives ICEs down to 4.9 for several testsuite files.

An incomplete list :
  ./gcc.c-torture/execute/20020413-1.c
  ./gcc.c-torture/compile/20031208-1.c
  ./gcc.c-torture/execute/20080502-1.c
  ./gcc.c-torture/compile/20080628-1.c
  ./gcc.c-torture/execute/va-arg-6.c
  ./gcc.dg/torture/float128-extend-inf.c
  ./gcc.dg/torture/float128-extend-nan.c
  ./gcc.dg/torture/float128-extendxf-underflow.c
  ./gcc.dg/torture/pr50092.c
  ./gcc.dg/tree-ssa/backprop-6.c
  ./gcc.dg/dfp/wtr-conversion-1.c
  ./gcc.dg/wtr-conversion-1.c
  ./gcc.dg/builtins-7.c
  ./gcc.dg/builtins-21.c
  ./gcc.dg/builtins-36.c
  ./gcc.dg/builtins-65.c
  ./gcc.dg/pr43305.c
  ./gcc.dg/pr46251.c
  ./gcc.dg/pr50132.c
  ./gcc.dg/pr52592.c
  ./gcc.dg/pr56424.c
  ./gcc.dg/pr68474.c


For example :

$ cat pr46251.c
void foo (long double *x)
{
  __builtin_sincosl (*x, x, x);
}


$ gcc-7-20170212 -m96bit-long-double -c pr46251.c
pr46251.c: In function 'foo':
pr46251.c:4:1: error: unable to generate reloads for:
 }
 ^
(insn 10 9 11 2 (set (mem:XF (pre_modify:DI (reg/f:DI 7 sp)
                (plus:DI (reg/f:DI 7 sp)
                    (const_int -16 [0xfffffffffffffff0]))) [2  S12 A32])
        (reg:XF 87 [ _1 ])) "pr46251.c":3 118 {*pushxf}
     (expr_list:REG_DEAD (reg:XF 87 [ _1 ])
        (expr_list:REG_ARGS_SIZE (const_int 16 [0x10])
            (nil))))
pr46251.c:4:1: internal compiler error: in curr_insn_transform, at
lra-constraints.c:3773
0xb894d8 _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
        ../../gcc/rtl-error.c:108
0xa87e17 curr_insn_transform
        ../../gcc/lra-constraints.c:3773
0xa89ce6 lra_constraints(bool)
        ../../gcc/lra-constraints.c:4732
0xa73ee6 lra(_IO_FILE*)
        ../../gcc/lra.c:2378
0xa2a389 do_reload
        ../../gcc/ira.c:5400
0xa2a389 execute
        ../../gcc/ira.c:5584