Can I assign left shift in relocation HOWTO table ??

Bongjin Kim billyjiny@gmail.com
Thu Oct 22 02:28:00 GMT 2009


 Thanks a lot.
 Now my binutils works well with the separated bitfield relocations.

> On Sat, Oct 17, 2009 at 04:17:49PM +0900, Bongjin Kim wrote:
>> but i need to split 9 bit and shift 4 high bits left to put them into insn.
>> is it possible? how can i do it?
>
> Use the howto special_function.  See elf32-spu.c:spu_elf_rel9 for one
> example.
>
>> because my ISA has no 32 bit immediate bit field.
>> in other words, i want my assembler can support 'macro' insn.
>> how can i do it?
>
> Write some support code.  See gas/config/tc-ppc.c ppc_macro_hash.
>
>> i saw '.set noreorder' in gcc output with -S option when delay slot is enabled
>> it means that assembler can reorder the insns, right?
>> if i want to reorder some insns according to certain rules,
>> because of the data dependencies,
>> how can i do it?
>
> mips is the only target I'm aware of that implements a ".set noreorder"
> that actually does something.  You can use tc-mips.c for example code,
> but I would recommend not implementing instruction reordering in gas.
> At least, not if you plan on porting higher level language compilers
> for your target.  A compiler can do a lot better job of instruction
> optimisation than an assembler.
>
> --
> Alan Modra
> Australia Development Lab, IBM
>



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