On Fri, Jul 30, 2021 at 8:40 AM Richard Sandiford
<richard.sandif...@arm.com> wrote:
>
> "H.J. Lu via Gcc-patches" <gcc-patches@gcc.gnu.org> writes:
> > +/* Callback routine for store_by_pieces. Read GET_MODE_BITSIZE (MODE)
> > + bytes from constant string DATA + OFFSET and return it as target
> > + constant. If PREV isn't nullptr, it has the RTL info from the
> > + previous iteration. */
> >
> > +rtx
> > +builtin_memset_read_str (void *data, void *prev,
> > + HOST_WIDE_INT offset ATTRIBUTE_UNUSED,
> > + fixed_size_mode mode)
> > +{
> > const char *c = (const char *) data;
> > - char *p = XALLOCAVEC (char, GET_MODE_SIZE (mode));
> > + unsigned int size = GET_MODE_SIZE (mode);
> >
> > - memset (p, *c, GET_MODE_SIZE (mode));
> > + rtx target = gen_memset_value_from_prev ((by_pieces_prev *) prev,
> > + mode);
> > + if (target != nullptr)
> > + return target;
> > + rtx src = gen_int_mode (*c, QImode);
> >
> > - return c_readstr (p, mode);
> > + if (VECTOR_MODE_P (mode))
> > + {
> > + gcc_assert (GET_MODE_INNER (mode) == QImode);
> > +
> > + rtx const_vec = gen_const_vec_duplicate (mode, src);
> > + if (prev == NULL)
> > + /* Return CONST_VECTOR when called by a query function. */
> > + target = const_vec;
> > + else
> > + {
> > + /* Use the move expander with CONST_VECTOR. */
> > + target = targetm.gen_memset_scratch_rtx (mode);
> > + emit_move_insn (target, const_vec);
> > + }
> > +
> > + return target;
>
> I guess this is personal preference, sorry, but it seems more obvious
> to me with an early return rather than an assignemnt to target:
>
> if (prev == NULL)
> /* Return CONST_VECTOR when called by a query function. */
> return const_vec;
>
> /* Use the move expander with CONST_VECTOR. */
> target = targetm.gen_memset_scratch_rtx (mode);
> emit_move_insn (target, const_vec);
> return target;
I made the change and checked it in. Thank you very much for your help.
> OK with that change, thanks, no need to repost. (And thanks for
> your patience.)
>
> Richard
--
H.J.
