This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: RFA: Fix modes in ctz libcall notes
- From: Richard Sandiford <rsandifo at nildram dot co dot uk>
- To: Paolo Bonzini <bonzini at gnu dot org>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Wed, 23 Jan 2008 18:28:46 +0000
- Subject: Re: RFA: Fix modes in ctz libcall notes
- References: <87hch4r7zf.fsf@firetop.home> <47974E4E.8000700@gnu.org>
Paolo Bonzini <bonzini@gnu.org> writes:
>> - emit_libcall_block (insns, target, value,
>> - gen_rtx_fmt_e (unoptab->code, outmode, op0));
>> + eq_value = gen_rtx_fmt_e (unoptab->code, mode, op0);
>> + if (GET_MODE_SIZE (outmode) < GET_MODE_SIZE (mode))
>> + eq_value = gen_rtx_TRUNCATE (outmode, eq_value);
>
> Why not simplifying this so that a SUBREG is created instead?
Having SUBREGs of anything other than MEMs and REGs seems less
than ideal. (For reference, we use TRUNCATEs for a similar
purpose when doing high-part multiplications.)
Richard