Re: [PATCH] Remove TARGET_GEN_MEMSET_SCRATCH_RTX since it's not used anymore.

[Richard Biener <richard.guenther@gmail.com>]

On Wed, Mar 22, 2023 at 8:07 AM Uros Bizjak <ubizjak@gmail.com> wrote:
>
> On Wed, Mar 22, 2023 at 3:59 AM liuhongt <hongtao.liu@intel.com> wrote:
> >
> > The target hook is only used by i386, and the current definition is
> > same as default gen_reg_rtx. So there's no need for this target hook.
> >
> > Bootstrapped and regtested on x86_64-pc-linux-gnu{-m32,}.
> > Ok for trunk(or GCC14)?
> >
> > gcc/ChangeLog:
> >
> >         * builtins.cc (builtin_memset_read_str): Replace
> >         targetm.gen_memset_scratch_rtx with gen_reg_rtx.
> >         (builtin_memset_gen_str): Ditto.
> >         * config/i386/i386-expand.cc
> >         (ix86_convert_const_wide_int_to_broadcast): Replace
> >         ix86_gen_scratch_sse_rtx with gen_reg_rtx.
> >         (ix86_expand_vector_move): Ditto.
> >         * config/i386/i386-protos.h (ix86_gen_scratch_sse_rtx):
> >         Removed.
> >         * config/i386/i386.cc (ix86_gen_scratch_sse_rtx): Removed.
> >         (TARGET_GEN_MEMSET_SCRATCH_RTX): Removed.
> >         * doc/tm.texi: Remove TARGET_GEN_MEMSET_SCRATCH_RTX.
> >         * doc/tm.texi.in: Ditto.
> >         * target.def: Ditto.
>
> Looks trivial enough for gcc13, so OK for x86 part.
>
> Needs also OK from a middle-end reviewer.

Is/was the code ever exercised for non-x86?  HJ, what was the reason to
abstract this?

OK if HJ thinks it was really unnecessary abstraction unlikely to be
required by another target.

Richard.

> Thanks,
> Uros.
>
> > ---
> >  gcc/builtins.cc                |  4 ++--
> >  gcc/config/i386/i386-expand.cc |  6 +++---
> >  gcc/config/i386/i386-protos.h  |  2 --
> >  gcc/config/i386/i386.cc        | 12 ------------
> >  gcc/doc/tm.texi                |  7 -------
> >  gcc/doc/tm.texi.in             |  2 --
> >  gcc/target.def                 |  9 ---------
> >  7 files changed, 5 insertions(+), 37 deletions(-)
> >
> > diff --git a/gcc/builtins.cc b/gcc/builtins.cc
> > index 90246e214d6..8026e2001b7 100644
> > --- a/gcc/builtins.cc
> > +++ b/gcc/builtins.cc
> > @@ -4212,7 +4212,7 @@ builtin_memset_read_str (void *data, void *prev,
> >         return const_vec;
> >
> >        /* Use the move expander with CONST_VECTOR.  */
> > -      target = targetm.gen_memset_scratch_rtx (mode);
> > +      target = gen_reg_rtx (mode);
> >        emit_move_insn (target, const_vec);
> >        return target;
> >      }
> > @@ -4256,7 +4256,7 @@ builtin_memset_gen_str (void *data, void *prev,
> >          the memset expander.  */
> >        insn_code icode = optab_handler (vec_duplicate_optab, mode);
> >
> > -      target = targetm.gen_memset_scratch_rtx (mode);
> > +      target = gen_reg_rtx (mode);
> >        class expand_operand ops[2];
> >        create_output_operand (&ops[0], target, mode);
> >        create_input_operand (&ops[1], (rtx) data, QImode);
> > diff --git a/gcc/config/i386/i386-expand.cc b/gcc/config/i386/i386-expand.cc
> > index c1300dc4e26..1e3ce4b7c3f 100644
> > --- a/gcc/config/i386/i386-expand.cc
> > +++ b/gcc/config/i386/i386-expand.cc
> > @@ -338,7 +338,7 @@ ix86_convert_const_wide_int_to_broadcast (machine_mode mode, rtx op)
> >    machine_mode vector_mode;
> >    if (!mode_for_vector (broadcast_mode, nunits).exists (&vector_mode))
> >      gcc_unreachable ();
> > -  rtx target = ix86_gen_scratch_sse_rtx (vector_mode);
> > +  rtx target = gen_reg_rtx (vector_mode);
> >    bool ok = ix86_expand_vector_init_duplicate (false, vector_mode,
> >                                                target,
> >                                                GEN_INT (val_broadcast));
> > @@ -686,7 +686,7 @@ ix86_expand_vector_move (machine_mode mode, rtx operands[])
> >        if (!register_operand (op0, mode)
> >           && !register_operand (op1, mode))
> >         {
> > -         rtx scratch = ix86_gen_scratch_sse_rtx (mode);
> > +         rtx scratch = gen_reg_rtx (mode);
> >           emit_move_insn (scratch, op1);
> >           op1 = scratch;
> >         }
> > @@ -728,7 +728,7 @@ ix86_expand_vector_move (machine_mode mode, rtx operands[])
> >        && !register_operand (op0, mode)
> >        && !register_operand (op1, mode))
> >      {
> > -      rtx tmp = ix86_gen_scratch_sse_rtx (GET_MODE (op0));
> > +      rtx tmp = gen_reg_rtx (GET_MODE (op0));
> >        emit_move_insn (tmp, op1);
> >        emit_move_insn (op0, tmp);
> >        return;
> > diff --git a/gcc/config/i386/i386-protos.h b/gcc/config/i386/i386-protos.h
> > index bfb2198265a..71ae95ffef7 100644
> > --- a/gcc/config/i386/i386-protos.h
> > +++ b/gcc/config/i386/i386-protos.h
> > @@ -50,8 +50,6 @@ extern void ix86_reset_previous_fndecl (void);
> >
> >  extern bool ix86_using_red_zone (void);
> >
> > -extern rtx ix86_gen_scratch_sse_rtx (machine_mode);
> > -
> >  extern unsigned int ix86_regmode_natural_size (machine_mode);
> >  extern bool ix86_check_builtin_isa_match (unsigned int fcode);
> >  #ifdef RTX_CODE
> > diff --git a/gcc/config/i386/i386.cc b/gcc/config/i386/i386.cc
> > index 5d0e4739a84..6a8734c2346 100644
> > --- a/gcc/config/i386/i386.cc
> > +++ b/gcc/config/i386/i386.cc
> > @@ -24197,15 +24197,6 @@ ix86_optab_supported_p (int op, machine_mode mode1, machine_mode,
> >      }
> >  }
> >
> > -/* Implement the TARGET_GEN_MEMSET_SCRATCH_RTX hook.  Return a scratch
> > -   register in MODE for vector load and store.  */
> > -
> > -rtx
> > -ix86_gen_scratch_sse_rtx (machine_mode mode)
> > -{
> > -  return gen_reg_rtx (mode);
> > -}
> > -
> >  /* Address space support.
> >
> >     This is not "far pointers" in the 16-bit sense, but an easy way
> > @@ -25253,9 +25244,6 @@ static bool ix86_libc_has_fast_function (int fcode ATTRIBUTE_UNUSED)
> >  #undef TARGET_LIBC_HAS_FAST_FUNCTION
> >  #define TARGET_LIBC_HAS_FAST_FUNCTION ix86_libc_has_fast_function
> >
> > -#undef TARGET_GEN_MEMSET_SCRATCH_RTX
> > -#define TARGET_GEN_MEMSET_SCRATCH_RTX ix86_gen_scratch_sse_rtx
> > -
> >  #if CHECKING_P
> >  #undef TARGET_RUN_TARGET_SELFTESTS
> >  #define TARGET_RUN_TARGET_SELFTESTS selftest::ix86_run_selftests
> > diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
> > index c4a92a5ebee..4bb48c5428c 100644
> > --- a/gcc/doc/tm.texi
> > +++ b/gcc/doc/tm.texi
> > @@ -12001,13 +12001,6 @@ This function prepares to emit a conditional comparison within a sequence
> >   @var{bit_code} is @code{AND} or @code{IOR}, which is the op on the compares.
> >  @end deftypefn
> >
> > -@deftypefn {Target Hook} rtx TARGET_GEN_MEMSET_SCRATCH_RTX (machine_mode @var{mode})
> > -This hook should return an rtx for a scratch register in @var{mode} to
> > -be used when expanding memset calls.  The backend can use a hard scratch
> > -register to avoid stack realignment when expanding memset.  The default
> > -is @code{gen_reg_rtx}.
> > -@end deftypefn
> > -
> >  @deftypefn {Target Hook} unsigned TARGET_LOOP_UNROLL_ADJUST (unsigned @var{nunroll}, class loop *@var{loop})
> >  This target hook returns a new value for the number of times @var{loop}
> >  should be unrolled. The parameter @var{nunroll} is the number of times
> > diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
> > index 4075e71624c..f7ab5d48a63 100644
> > --- a/gcc/doc/tm.texi.in
> > +++ b/gcc/doc/tm.texi.in
> > @@ -7787,8 +7787,6 @@ lists.
> >
> >  @hook TARGET_GEN_CCMP_NEXT
> >
> > -@hook TARGET_GEN_MEMSET_SCRATCH_RTX
> > -
> >  @hook TARGET_LOOP_UNROLL_ADJUST
> >
> >  @defmac POWI_MAX_MULTS
> > diff --git a/gcc/target.def b/gcc/target.def
> > index f401fe148ee..1b9c882229e 100644
> > --- a/gcc/target.def
> > +++ b/gcc/target.def
> > @@ -2738,15 +2738,6 @@ DEFHOOK
> >   rtx, (rtx_insn **prep_seq, rtx_insn **gen_seq, rtx prev, int cmp_code, tree op0, tree op1, int bit_code),
> >   NULL)
> >
> > -DEFHOOK
> > -(gen_memset_scratch_rtx,
> > - "This hook should return an rtx for a scratch register in @var{mode} to\n\
> > -be used when expanding memset calls.  The backend can use a hard scratch\n\
> > -register to avoid stack realignment when expanding memset.  The default\n\
> > -is @code{gen_reg_rtx}.",
> > - rtx, (machine_mode mode),
> > - gen_reg_rtx)
> > -
> >  /* Return a new value for loop unroll size.  */
> >  DEFHOOK
> >  (loop_unroll_adjust,
> > --
> > 2.39.1.388.g2fc9e9ca3c
> >