[Bug tree-optimization/15791] fold misses that two ADDR_EXPR of an arrary obvious not equal

["rguenth at tat dot physik dot uni-tuebingen dot de" <gcc-bugzilla at gcc dot gnu dot org>]

------- Additional Comments From rguenth at tat dot physik dot uni-tuebingen dot de  2005-01-27 14:53 -------
Bootstrapping and testing completed successfully, but for the testcase

int g(void)
{
   struct { int b[2]; } x;
   return &x.b[0] == &x.b[1];
}

we have lowered the comparison to

 <eq_expr 0x40148264
    type <integer_type 0x40149510 int public SI
        size <integer_cst 0x40141408 constant invariant 32>
        unit size <integer_cst 0x40141198 constant invariant 4>
        align 32 symtab 0 alias set -1 precision 32 min <integer_cst 0x401413c0
-2147483648> max <integer_cst 0x401413d8 2147483647>
        pointer_to_this <pointer_type 0x401569b4>>
    invariant
    arg 0 <nop_expr 0x40146300
        type <pointer_type 0x401569b4 type <integer_type 0x40149510 int>
            public unsigned SI size <integer_cst 0x40141408 32> unit size
<integer_cst 0x40141198 4>
            align 32 symtab 0 alias set -1>
        invariant
        arg 0 <addr_expr 0x40146280 type <pointer_type 0x401b521c>
            invariant
            arg 0 <component_ref 0x4014d078 type <array_type 0x401b5000>
                arg 0 <var_decl 0x401b51b0 x> arg 1 <field_decl 0x401b506c b>>>>
    arg 1 <plus_expr 0x40148240 type <pointer_type 0x401569b4>
        invariant
        arg 0 <nop_expr 0x40146340 type <pointer_type 0x401569b4>
            invariant
            arg 0 <addr_expr 0x40146320 type <pointer_type 0x401b521c>
                invariant
                arg 0 <component_ref 0x4014d0a0 type <array_type 0x401b5000>
                    arg 0 <var_decl 0x401b51b0 x> arg 1 <field_decl 0x401b506c b>>>>
        arg 1 <integer_cst 0x40141d50 constant invariant 4>>>

and what confuses is the extra(?) nop_exprs - can I somehow avoid adding another
path for this case?

-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=15791