https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102133
--- Comment #3 from Hongtao.liu <crazylht at gmail dot com> ---
static inline void
set_rtl (tree t, rtx x)
{
gcc_checking_assert (!x
|| !(TREE_CODE (t) == SSA_NAME || is_gimple_reg (t))
|| (use_register_for_decl (t)
? (REG_P (x)
|| (GET_CODE (x) == CONCAT
&& (REG_P (XEXP (x, 0))
|| SUBREG_P (XEXP (x, 0)))
&& (REG_P (XEXP (x, 1))
|| SUBREG_P (XEXP (x, 1))))
/* We need to accept PARALLELs for RESUT_DECLs
because of vector types with BLKmode returned
in multiple registers, but they are supposed
to be uncoalesced. */
|| (GET_CODE (x) == PARALLEL
&& SSAVAR (t)
&& TREE_CODE (SSAVAR (t)) == RESULT_DECL
&& (GET_MODE (x) == BLKmode
|| !flag_tree_coalesce_vars)))
: (MEM_P (x) || x == pc_rtx
|| (GET_CODE (x) == CONCAT
&& MEM_P (XEXP (x, 0))
&& MEM_P (XEXP (x, 1))))));
x is
(subreg:DF (reg:DI 154) 0),
t is
<ssa_name 0x7fffea4a9a68
type <real_type 0x7fffea48b1f8 DFtype sizes-gimplified DF
size <integer_cst 0x7fffea2e2e10 constant 64>
unit-size <integer_cst 0x7fffea2e2e28 constant 8>
align:64 warn_if_not_align:0 symtab:0 alias-set -1 canonical-type
0x7fffea2f9498 precision:64 context <translation_unit_decl 0x7fffea49c078
/scratch/jmyers/glibc/many12/src/gcc/libgcc/libgcc2.c>>
visited var <parm_decl 0x7fffea497b00 d>
def_stmt GIMPLE_NOP
version:62>
and it hit REG_P (XEXP (x, 1)), XEXP (x, 1) is invalid for subreg, so set_rtl
here doesn't accept subreg?
