Return the profile init irg from ir_profile_instrument() instead of guessing that it is the last irg.

We can now pull instructions from other blocks up and use the annul bits
if profitable.

so external users can set their own opcode functions.

Still broken for anything except int f(void) { return 0; } though...

You can still attach NoMem if no memory input is present.
This makes it more consistent with the Call node and fixes failing
get_ASM_mem in case of no memory input.

This makes it consistent with other functions like get_irn_arity().
(Though I must admit that we should change all these functions from
 "int" to unsigned at some point)

After the switch to C99, the foreach_ir_nodeset macro introduced a separate
loop variable, which shadowed the local variable "irn".  Thus, an uninitialized
pointer was passed to is_cfop.

This fixes backend/setmem.c.

Let list_for_each_entry(), list_for_each_entry_reverse() and list_for_each_entry_safe() declare their iterator variables.

It is identical to list_for_each(), though its comment claimed otherwise.

Let matrix_foreach(), matrix_foreach_in_col() and matrix_foreach_in_row() declare their iterator variables.

Remove now redundant (and sometimes wrong) location info from the panic messages.