On Thu, Jun 3, 2021 at 11:21 PM Uros Bizjak <ubiz...@gmail.com> wrote:
>
> On Fri, Jun 4, 2021 at 12:39 AM H.J. Lu <hjl.to...@gmail.com> wrote:
> >
> > On Thu, Jun 3, 2021 at 12:39 AM Uros Bizjak <ubiz...@gmail.com> wrote:
> > >
> > > On Thu, Jun 3, 2021 at 5:49 AM H.J. Lu <hjl.to...@gmail.com> wrote:
> > > >
> > > > Update move expanders to convert the CONST_WIDE_INT operand to vector
> > > > broadcast from a byte with AVX2. Add ix86_gen_scratch_sse_rtx to
> > > > return a scratch SSE register which won't increase stack alignment
> > > > requirement and blocks transformation by the combine pass.
> > >
> > > Using fixed scratch reg is just too hackish for my taste. The
> >
> > It was recommended to use hard register for things like this:
> >
> > https://gcc.gnu.org/pipermail/gcc-patches/2021-May/569945.html
>
> I was worried that the temporary (even hard reg) will be spilled under
> some rare cases. If this is not the case, and even recommended for
> your use case, then it should be OK. Maybe use a hard register instead
> of match_scratch in the clobber of the proposed insn pattern below.
With a hard register, we can add
;; Modes handled by byte broadcast patterns.
(define_mode_iterator BYTE_BROADCAST_MODE
[(V64QI "TARGET_AVX512F") (V32QI "TARGET_AVX") V16QI])
;; Broadcast from a byte.
(define_expand "vec_duplicate<mode>"
[(set (match_operand:BYTE_BROADCAST_MODE 0 "register_operand")
(vec_duplicate:BYTE_BROADCAST_MODE
(match_operand:QI 1 "general_operand")))]
"TARGET_SSE2"
{
/* Enable VEC_DUPLICATE from a constant byte only if vector broadcast
is available. Otherwise use a compile-time constant to expand
memset. */
if (!TARGET_AVX2 && CONST_INT_P (operands[1]))
FAIL;
if (!ix86_expand_vector_init_duplicate (false, <MODE>mode,
operands[0], operands[1]))
gcc_unreachable ();
DONE;
})
> > > expansion is OK to emit some optimized sequence, but the approach to
> > > use fixed reg to bypass stack alignment functionality and combine is
> > > not.
> > >
> > > Perhaps a new insn pattern should be introduced, e.g.
> > >
> > > (define_insn_and_split ""
> > > [(set (match_opreand:V 0 "memory_operand" "=m,m")
> > > (vec_duplicate:V
> > > (match_operand:S 2 "reg_or_0_operand" "r,C"))
> > > (clobber (match_scratch:V 1 "=x"))]
> > >
> > > and split it at some appropriate point.
>
> Please note that zero (C) can be assigned directly to the XMM
> register, so there is no need for the intermediate integer reg,
> assuming that zero was propagated into the insn (-1 can be handled
> this way, too). Due to these propagations, it looks that the correct
> point to split the insn is after the reload.
On the other hand, we can do
unsigned int nunits = GET_MODE_SIZE (mode) / GET_MODE_SIZE (QImode);
machine_mode vector_mode;
if (!mode_for_vector (QImode, nunits).exists (&vector_mode))
gcc_unreachable ();
target = ix86_gen_scratch_sse_rtx (vector_mode, true);
rtx byte = GEN_INT ((char) byte_broadcast);
if (!ix86_expand_vector_init_duplicate (false, vector_mode, target,
byte))
gcc_unreachable ();
This generates the same instruction and is much simpler.
ix86_expand_vector_init_duplicate can handle 0 and -1 properly.
> On a related note, you are using only vpbroadcastb, assuming byte
> (QImode) granularity. Is it possible to also use HImode and larger
> modes to handle e.g. initializations of int arrays?
I will work on it.
> Uros.
>
> > I will give it a try.
> >
> > Thanks.
> >
> > > Uros.
> > >
> > > >
> > > > A small benchmark:
> > > >
> > > > https://gitlab.com/x86-benchmarks/microbenchmark/-/tree/memset/broadcast
> > > >
> > > > shows that broadcast is a little bit faster on Intel Core i7-8559U:
> > > >
> > > > $ make
> > > > gcc -g -I. -O2 -c -o test.o test.c
> > > > gcc -g -c -o memory.o memory.S
> > > > gcc -g -c -o broadcast.o broadcast.S
> > > > gcc -o test test.o memory.o broadcast.o
> > > > ./test
> > > > memory : 99333
> > > > broadcast: 97208
> > > > $
> > > >
> > > > broadcast is also smaller:
> > > >
> > > > $ size memory.o broadcast.o
> > > > text data bss dec hex filename
> > > > 132 0 0 132 84 memory.o
> > > > 122 0 0 122 7a broadcast.o
> > > > $
> > > >
> > > > gcc/
> > > >
> > > > PR target/100865
> > > > * config/i386/i386-expand.c (ix86_expand_vector_init_duplicate):
> > > > New prototype.
> > > > (ix86_byte_broadcast): New function.
> > > > (ix86_convert_const_wide_int_to_broadcast): Likewise.
> > > > (ix86_expand_move): Try ix86_convert_const_wide_int_to_broadcast
> > > > if mode size is 16 bytes or bigger.
> > > > (ix86_expand_vector_move): Try
> > > > ix86_convert_const_wide_int_to_broadcast.
> > > > * config/i386/i386-protos.h (ix86_gen_scratch_sse_rtx): New
> > > > prototype.
> > > > * config/i386/i386.c (ix86_minimum_incoming_stack_boundary): Add
> > > > an argument to ignore stack_alignment_estimated. It is passed
> > > > as false by default.
> > > > (ix86_gen_scratch_sse_rtx): New function.
> > > >
> > > > gcc/testsuite/
> > > >
> > > > PR target/100865
> > > > * gcc.target/i386/pr100865-1.c: New test.
> > > > * gcc.target/i386/pr100865-2.c: Likewise.
> > > > * gcc.target/i386/pr100865-3.c: Likewise.
> > > > * gcc.target/i386/pr100865-4.c: Likewise.
> > > > * gcc.target/i386/pr100865-5.c: Likewise.
> > > > ---
> > > > gcc/config/i386/i386-expand.c | 103 ++++++++++++++++++---
> > > > gcc/config/i386/i386-protos.h | 2 +
> > > > gcc/config/i386/i386.c | 50 +++++++++-
> > > > gcc/testsuite/gcc.target/i386/pr100865-1.c | 13 +++
> > > > gcc/testsuite/gcc.target/i386/pr100865-2.c | 14 +++
> > > > gcc/testsuite/gcc.target/i386/pr100865-3.c | 15 +++
> > > > gcc/testsuite/gcc.target/i386/pr100865-4.c | 16 ++++
> > > > gcc/testsuite/gcc.target/i386/pr100865-5.c | 17 ++++
> > > > 8 files changed, 215 insertions(+), 15 deletions(-)
> > > > create mode 100644 gcc/testsuite/gcc.target/i386/pr100865-1.c
> > > > create mode 100644 gcc/testsuite/gcc.target/i386/pr100865-2.c
> > > > create mode 100644 gcc/testsuite/gcc.target/i386/pr100865-3.c
> > > > create mode 100644 gcc/testsuite/gcc.target/i386/pr100865-4.c
> > > > create mode 100644 gcc/testsuite/gcc.target/i386/pr100865-5.c
> > > >
> > > > diff --git a/gcc/config/i386/i386-expand.c
> > > > b/gcc/config/i386/i386-expand.c
> > > > index 4185f58eed5..658adafa269 100644
> > > > --- a/gcc/config/i386/i386-expand.c
> > > > +++ b/gcc/config/i386/i386-expand.c
> > > > @@ -93,6 +93,9 @@ along with GCC; see the file COPYING3. If not see
> > > > #include "i386-builtins.h"
> > > > #include "i386-expand.h"
> > > >
> > > > +static bool ix86_expand_vector_init_duplicate (bool, machine_mode, rtx,
> > > > + rtx);
> > > > +
> > > > /* Split one or more double-mode RTL references into pairs of half-mode
> > > > references. The RTL can be REG, offsettable MEM, integer constant,
> > > > or
> > > > CONST_DOUBLE. "operands" is a pointer to an array of double-mode
> > > > RTLs to
> > > > @@ -190,6 +193,65 @@ ix86_expand_clear (rtx dest)
> > > > emit_insn (tmp);
> > > > }
> > > >
> > > > +/* Return a byte value which V can be broadcasted from. Otherwise,
> > > > + return INT_MAX. */
> > > > +
> > > > +static int
> > > > +ix86_byte_broadcast (HOST_WIDE_INT v)
> > > > +{
> > > > + wide_int val = wi::uhwi (v, HOST_BITS_PER_WIDE_INT);
> > > > + int byte_broadcast = wi::extract_uhwi (val, 0, BITS_PER_UNIT);
> > > > + for (unsigned int i = BITS_PER_UNIT;
> > > > + i < HOST_BITS_PER_WIDE_INT;
> > > > + i += BITS_PER_UNIT)
> > > > + {
> > > > + int byte = wi::extract_uhwi (val, i, BITS_PER_UNIT);
> > > > + if (byte_broadcast != byte)
> > > > + return INT_MAX;
> > > > + }
> > > > + return byte_broadcast;
> > > > +}
> > > > +
> > > > +/* Convert the CONST_WIDE_INT operand OP to broadcast in MODE. */
> > > > +
> > > > +static rtx
> > > > +ix86_convert_const_wide_int_to_broadcast (machine_mode mode, rtx op)
> > > > +{
> > > > + rtx target = nullptr;
> > > > +
> > > > + /* Convert CONST_WIDE_INT to broadcast only if vector broadcast is
> > > > + available. */
> > > > + if (!TARGET_AVX2 || !CONST_WIDE_INT_P (op))
> > > > + return target;
> > > > +
> > > > + HOST_WIDE_INT val = CONST_WIDE_INT_ELT (op, 0);
> > > > + int byte_broadcast = ix86_byte_broadcast (val);
> > > > +
> > > > + if (byte_broadcast == INT_MAX)
> > > > + return target;
> > > > +
> > > > + /* Check if OP1 can be broadcasted from VAL. */
> > > > + for (int i = 1; i < CONST_WIDE_INT_NUNITS (op); i++)
> > > > + if (val != CONST_WIDE_INT_ELT (op, i))
> > > > + return target;
> > > > +
> > > > + unsigned int nunits = GET_MODE_SIZE (mode) / GET_MODE_SIZE (QImode);
> > > > + machine_mode vector_mode;
> > > > + if (!mode_for_vector (QImode, nunits).exists (&vector_mode))
> > > > + gcc_unreachable ();
> > > > + target = ix86_gen_scratch_sse_rtx (vector_mode, true);
> > > > + rtx byte = GEN_INT ((char) byte_broadcast);
> > > > + if (!ix86_expand_vector_init_duplicate (false, vector_mode, target,
> > > > + byte))
> > > > + gcc_unreachable ();
> > > > + if (REGNO (target) < FIRST_PSEUDO_REGISTER)
> > > > + target = gen_rtx_REG (mode, REGNO (target));
> > > > + else
> > > > + target = convert_to_mode (mode, target, 1);
> > > > +
> > > > + return target;
> > > > +}
> > > > +
> > > > void
> > > > ix86_expand_move (machine_mode mode, rtx operands[])
> > > > {
> > > > @@ -347,20 +409,29 @@ ix86_expand_move (machine_mode mode, rtx
> > > > operands[])
> > > > && optimize)
> > > > op1 = copy_to_mode_reg (mode, op1);
> > > >
> > > > - if (can_create_pseudo_p ()
> > > > - && CONST_DOUBLE_P (op1))
> > > > + if (can_create_pseudo_p ())
> > > > {
> > > > - /* If we are loading a floating point constant to a register,
> > > > - force the value to memory now, since we'll get better code
> > > > - out the back end. */
> > > > + if (CONST_DOUBLE_P (op1))
> > > > + {
> > > > + /* If we are loading a floating point constant to a
> > > > + register, force the value to memory now, since we'll
> > > > + get better code out the back end. */
> > > >
> > > > - op1 = validize_mem (force_const_mem (mode, op1));
> > > > - if (!register_operand (op0, mode))
> > > > + op1 = validize_mem (force_const_mem (mode, op1));
> > > > + if (!register_operand (op0, mode))
> > > > + {
> > > > + rtx temp = gen_reg_rtx (mode);
> > > > + emit_insn (gen_rtx_SET (temp, op1));
> > > > + emit_move_insn (op0, temp);
> > > > + return;
> > > > + }
> > > > + }
> > > > + else if (GET_MODE_SIZE (mode) >= 16)
> > > > {
> > > > - rtx temp = gen_reg_rtx (mode);
> > > > - emit_insn (gen_rtx_SET (temp, op1));
> > > > - emit_move_insn (op0, temp);
> > > > - return;
> > > > + rtx tmp = ix86_convert_const_wide_int_to_broadcast
> > > > + (GET_MODE (op0), op1);
> > > > + if (tmp != nullptr)
> > > > + op1 = tmp;
> > > > }
> > > > }
> > > > }
> > > > @@ -407,7 +478,15 @@ ix86_expand_vector_move (machine_mode mode, rtx
> > > > operands[])
> > > > op1 = simplify_gen_subreg (mode, r, imode, SUBREG_BYTE (op1));
> > > > }
> > > > else
> > > > - op1 = validize_mem (force_const_mem (mode, op1));
> > > > + {
> > > > + machine_mode mode = GET_MODE (op0);
> > > > + rtx tmp = ix86_convert_const_wide_int_to_broadcast
> > > > + (mode, op1);
> > > > + if (tmp == nullptr)
> > > > + op1 = validize_mem (force_const_mem (mode, op1));
> > > > + else
> > > > + op1 = tmp;
> > > > + }
> > > > }
> > > >
> > > > /* We need to check memory alignment for SSE mode since attribute
> > > > diff --git a/gcc/config/i386/i386-protos.h
> > > > b/gcc/config/i386/i386-protos.h
> > > > index 7782cf1163f..01b3775df92 100644
> > > > --- a/gcc/config/i386/i386-protos.h
> > > > +++ b/gcc/config/i386/i386-protos.h
> > > > @@ -50,6 +50,8 @@ extern void ix86_reset_previous_fndecl (void);
> > > >
> > > > extern bool ix86_using_red_zone (void);
> > > >
> > > > +extern rtx ix86_gen_scratch_sse_rtx (machine_mode, bool);
> > > > +
> > > > extern unsigned int ix86_regmode_natural_size (machine_mode);
> > > > #ifdef RTX_CODE
> > > > extern int standard_80387_constant_p (rtx);
> > > > diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
> > > > index 04649b42122..3595fb5778e 100644
> > > > --- a/gcc/config/i386/i386.c
> > > > +++ b/gcc/config/i386/i386.c
> > > > @@ -415,7 +415,8 @@ static unsigned int
> > > > split_stack_prologue_scratch_regno (void);
> > > > static bool i386_asm_output_addr_const_extra (FILE *, rtx);
> > > >
> > > > static bool ix86_can_inline_p (tree, tree);
> > > > -static unsigned int ix86_minimum_incoming_stack_boundary (bool);
> > > > +static unsigned int ix86_minimum_incoming_stack_boundary (bool,
> > > > + bool = false);
> > > >
> > > >
> > > > /* Whether -mtune= or -march= were specified */
> > > > @@ -7232,7 +7233,8 @@ find_drap_reg (void)
> > > > /* Return minimum incoming stack alignment. */
> > > >
> > > > static unsigned int
> > > > -ix86_minimum_incoming_stack_boundary (bool sibcall)
> > > > +ix86_minimum_incoming_stack_boundary (bool sibcall,
> > > > + bool ignore_estimated)
> > > > {
> > > > unsigned int incoming_stack_boundary;
> > > >
> > > > @@ -7247,7 +7249,8 @@ ix86_minimum_incoming_stack_boundary (bool
> > > > sibcall)
> > > > estimated stack alignment is 128bit. */
> > > > else if (!sibcall
> > > > && ix86_force_align_arg_pointer
> > > > - && crtl->stack_alignment_estimated == 128)
> > > > + && (ignore_estimated
> > > > + || crtl->stack_alignment_estimated == 128))
> > > > incoming_stack_boundary = MIN_STACK_BOUNDARY;
> > > > else
> > > > incoming_stack_boundary = ix86_default_incoming_stack_boundary;
> > > > @@ -23061,6 +23064,47 @@ ix86_optab_supported_p (int op, machine_mode
> > > > mode1, machine_mode,
> > > > }
> > > > }
> > > >
> > > > +/* Return a scratch register in MODE for vector load and store. If
> > > > + CONSTANT_BROADCAST is true, it is used to hold constant broadcast
> > > > + result. */
> > > > +
> > > > +rtx
> > > > +ix86_gen_scratch_sse_rtx (machine_mode mode, bool constant_broadcast)
> > > > +{
> > > > + bool need_hard_reg = false;
> > > > +
> > > > + /* NB: Choose a hard scratch SSE register:
> > > > + 1. Avoid increasing stack alignment requirement.
> > > > + 2. for constant broadcast in 64-bit mode, avoid transformation by
> > > > + the combine pass.
> > > > + */
> > > > + if (GET_MODE_SIZE (mode) >= 16
> > > > + && !COMPLEX_MODE_P (mode)
> > > > + && (SCALAR_INT_MODE_P (mode) || VECTOR_MODE_P (mode)))
> > > > + {
> > > > + if (constant_broadcast
> > > > + && TARGET_64BIT
> > > > + && GET_MODE_SIZE (mode) == 16)
> > > > + need_hard_reg = true;
> > > > + else
> > > > + {
> > > > + unsigned int incoming_stack_boundary
> > > > + = ix86_minimum_incoming_stack_boundary (false, true);
> > > > + if (GET_MODE_ALIGNMENT (mode) > incoming_stack_boundary)
> > > > + need_hard_reg = true;
> > > > + }
> > > > + }
> > > > +
> > > > + rtx target;
> > > > + if (need_hard_reg)
> > > > + target = gen_rtx_REG (mode, (TARGET_64BIT
> > > > + ? LAST_REX_SSE_REG
> > > > + : LAST_SSE_REG));
> > > > + else
> > > > + target = gen_reg_rtx (mode);
> > > > + return target;
> > > > +}
> > > > +
> > > > /* Address space support.
> > > >
> > > > This is not "far pointers" in the 16-bit sense, but an easy way
> > > > diff --git a/gcc/testsuite/gcc.target/i386/pr100865-1.c
> > > > b/gcc/testsuite/gcc.target/i386/pr100865-1.c
> > > > new file mode 100644
> > > > index 00000000000..6c3097fb2a6
> > > > --- /dev/null
> > > > +++ b/gcc/testsuite/gcc.target/i386/pr100865-1.c
> > > > @@ -0,0 +1,13 @@
> > > > +/* { dg-do compile { target { ! ia32 } } } */
> > > > +/* { dg-options "-O2 -march=x86-64" } */
> > > > +
> > > > +extern char *dst;
> > > > +
> > > > +void
> > > > +foo (void)
> > > > +{
> > > > + __builtin_memset (dst, 3, 16);
> > > > +}
> > > > +
> > > > +/* { dg-final { scan-assembler-times "movdqa\[ \\t\]+\[^\n\]*%xmm" 1 }
> > > > } */
> > > > +/* { dg-final { scan-assembler-times "movups\[\\t \]%xmm\[0-9\]+,
> > > > \\(%\[\^,\]+\\)" 1 } } */
> > > > diff --git a/gcc/testsuite/gcc.target/i386/pr100865-2.c
> > > > b/gcc/testsuite/gcc.target/i386/pr100865-2.c
> > > > new file mode 100644
> > > > index 00000000000..17efe2d72a3
> > > > --- /dev/null
> > > > +++ b/gcc/testsuite/gcc.target/i386/pr100865-2.c
> > > > @@ -0,0 +1,14 @@
> > > > +/* { dg-do compile { target { ! ia32 } } } */
> > > > +/* { dg-options "-O2 -march=skylake" } */
> > > > +
> > > > +extern char *dst;
> > > > +
> > > > +void
> > > > +foo (void)
> > > > +{
> > > > + __builtin_memset (dst, 3, 16);
> > > > +}
> > > > +
> > > > +/* { dg-final { scan-assembler-times "vpbroadcastb\[\\t
> > > > \]+%xmm\[0-9\]+, %xmm\[0-9\]+" 1 } } */
> > > > +/* { dg-final { scan-assembler-times "vmovdqu\[\\t \]%xmm\[0-9\]+,
> > > > \\(%\[\^,\]+\\)" 1 } } */
> > > > +/* { dg-final { scan-assembler-not "vmovdqa" } } */
> > > > diff --git a/gcc/testsuite/gcc.target/i386/pr100865-3.c
> > > > b/gcc/testsuite/gcc.target/i386/pr100865-3.c
> > > > new file mode 100644
> > > > index 00000000000..56665d8c9b6
> > > > --- /dev/null
> > > > +++ b/gcc/testsuite/gcc.target/i386/pr100865-3.c
> > > > @@ -0,0 +1,15 @@
> > > > +/* { dg-do compile { target { ! ia32 } } } */
> > > > +/* { dg-options "-O2 -march=skylake-avx512" } */
> > > > +
> > > > +extern char *dst;
> > > > +
> > > > +void
> > > > +foo (void)
> > > > +{
> > > > + __builtin_memset (dst, 3, 16);
> > > > +}
> > > > +
> > > > +/* { dg-final { scan-assembler-times "vpbroadcastb\[\\t \]+%.*,
> > > > %xmm\[0-9\]+" 1 } } */
> > > > +/* { dg-final { scan-assembler-times "vmovdqu\[\\t \]%xmm\[0-9\]+,
> > > > \\(%\[\^,\]+\\)" 1 } } */
> > > > +/* { dg-final { scan-assembler-not "vpbroadcastb\[\\t \]+%xmm\[0-9\]+,
> > > > %xmm\[0-9\]+" } } */
> > > > +/* { dg-final { scan-assembler-not "vmovdqa" } } */
> > > > diff --git a/gcc/testsuite/gcc.target/i386/pr100865-4.c
> > > > b/gcc/testsuite/gcc.target/i386/pr100865-4.c
> > > > new file mode 100644
> > > > index 00000000000..1622a06f57e
> > > > --- /dev/null
> > > > +++ b/gcc/testsuite/gcc.target/i386/pr100865-4.c
> > > > @@ -0,0 +1,16 @@
> > > > +/* { dg-do compile { target { ! ia32 } } } */
> > > > +/* { dg-options "-O2 -march=skylake" } */
> > > > +
> > > > +extern char array[64];
> > > > +
> > > > +void
> > > > +foo (void)
> > > > +{
> > > > + int i;
> > > > + for (i = 0; i < 64; i++)
> > > > + array[i] = -45;
> > > > +}
> > > > +
> > > > +/* { dg-final { scan-assembler-times "vpbroadcastb\[\\t
> > > > \]+%xmm\[0-9\]+, %xmm\[0-9\]+" 1 } } */
> > > > +/* { dg-final { scan-assembler-times "vmovdqu\[\\t \]%xmm\[0-9\]+, " 4
> > > > } } */
> > > > +/* { dg-final { scan-assembler-not "vmovdqa" } } */
> > > > diff --git a/gcc/testsuite/gcc.target/i386/pr100865-5.c
> > > > b/gcc/testsuite/gcc.target/i386/pr100865-5.c
> > > > new file mode 100644
> > > > index 00000000000..66040d9f972
> > > > --- /dev/null
> > > > +++ b/gcc/testsuite/gcc.target/i386/pr100865-5.c
> > > > @@ -0,0 +1,17 @@
> > > > +/* { dg-do compile { target { ! ia32 } } } */
> > > > +/* { dg-options "-O2 -march=skylake-avx512" } */
> > > > +
> > > > +extern char array[64];
> > > > +
> > > > +void
> > > > +foo (void)
> > > > +{
> > > > + int i;
> > > > + for (i = 0; i < 64; i++)
> > > > + array[i] = -45;
> > > > +}
> > > > +
> > > > +/* { dg-final { scan-assembler-times "vpbroadcastb\[\\t \]+%.*,
> > > > %xmm\[0-9\]+" 1 } } */
> > > > +/* { dg-final { scan-assembler-times "vmovdqu\[\\t \]%xmm\[0-9\]+, " 4
> > > > } } */
> > > > +/* { dg-final { scan-assembler-not "vpbroadcastb\[\\t \]+%xmm\[0-9\]+,
> > > > %xmm\[0-9\]+" } } */
> > > > +/* { dg-final { scan-assembler-not "vmovdqa" } } */
> > > > --
> > > > 2.31.1
> > > >
> >
> >
> >
> > --
> > H.J.
--
H.J.
