Targets like arm, hppa and sh64 use the lower bits of the address
of functions for special purposes.  Even on those targets,

----
extern void plabel32_function (void);

int
is_plabel32 (void)
{
  return ((unsigned long) &plabel32_function & 3);
}
----

which was the test case of PR 35705, is wrongly compiled with -O2.
It seems that tree-bit-ccp optimization evaluates the expression
((unsigned long) &plabel32_function & 3) to zero always.
With -fno-tree-bit-ccp, the result looks OK.  For example, arm-eabi
compiler outputs

	mov	r0, #0
	bx	lr

with -O2 and

	ldr	r0, .L2
	and	r0, r0, #3
	bx	lr
.L3:
	.align	2
.L2:
	.word	plabel32_function

with -O2 -fno-tree-bit-ccp.  I've got similar results for hppa and sh64
compilers.