From: "H.J. Lu" <hjl.tools@gmail.com>
To: Noah Goldstein <goldstein.w.n@gmail.com>
Cc: libc-alpha@sourceware.org, carlos@systemhalted.org
Subject: Re: [PATCH v3 2/5] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-evex functions
Date: Fri, 4 Nov 2022 15:47:20 -0700 [thread overview]
Message-ID: <CAMe9rOptNXqDS559bjuArvRhFYqprED+V2Z2xq7FWPU-RwTWrg@mail.gmail.com> (raw)
In-Reply-To: <CAFUsyf+CR+W1Qs2oMhPm33Zf6g5VKQ=XfWcznP2STN-5PDUoWg@mail.gmail.com>
On Fri, Nov 4, 2022 at 3:28 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> On Fri, Nov 4, 2022 at 2:46 PM H.J. Lu <hjl.tools@gmail.com> wrote:
> >
> > On Fri, Nov 04, 2022 at 01:13:11PM -0700, Noah Goldstein wrote:
> > > Optimizations are:
> > > 1. Use more overlapping stores to avoid branches.
> > > 2. Reduce how unrolled the aligning copies are (this is more of a
> > > code-size save, its a negative for some sizes in terms of
> > > perf).
> > > 3. Improve the loop a bit (similiar to what we do in strlen with
> > > 2x vpminu + kortest instead of 3x vpminu + kmov + test).
> > > 4. For st{r|p}n{cat|cpy} re-order the branches to minimize the
> > > number that are taken.
> > >
> > > Performance Changes:
> > >
> > > Times are from N = 10 runs of the benchmark suite and are
> > > reported as geometric mean of all ratios of
> > > New Implementation / Old Implementation.
> > >
> > > stpcpy-evex -> 0.922
> > > strcat-evex -> 0.985
> > > strcpy-evex -> 0.880
> > >
> > > strncpy-evex -> 0.831
> > > stpncpy-evex -> 0.780
> > >
> > > strncat-evex -> 0.958
> > >
> > > Code Size Changes:
> > > function -> Bytes New / Bytes Old -> Ratio
> > >
> > > strcat-evex -> 819 / 1874 -> 0.437
> > > strcpy-evex -> 700 / 1074 -> 0.652
> > > stpcpy-evex -> 735 / 1094 -> 0.672
> > >
> > > strncpy-evex -> 1397 / 2611 -> 0.535
> > > stpncpy-evex -> 1489 / 2691 -> 0.553
> > >
> > > strncat-evex -> 1184 / 2832 -> 0.418
> > >
> > > Notes:
> > > 1. Because of the significant difference between the
> > > implementations they are split into three files.
> > >
> > > strcpy-evex.S -> strcpy, stpcpy, strcat
> > > strncpy-evex.S -> strncpy
> > > strncat-evex.S > strncat
> > >
> > > I couldn't find a way to merge them without making the
> > > ifdefs incredibly difficult to follow.
> > >
> > > 2. All implementations can be made evex512 by including
> > > "x86-evex512-vecs.h" at the top.
> > >
> > > 3. All implementations have an optional define:
> > > `USE_EVEX_MASKED_STORE`
> > > Setting to one uses evex-masked stores for handling short
> > > strings. This saves code size and branches. It's disabled
> > > for all implementations are the moment as there are some
> > > serious drawbacks to masked stores in certain cases, but
> > > that may be fixed on future architectures.
> > >
> > > Full check passes on x86-64 and build succeeds for all ISA levels w/
> > > and w/o multiarch.
> > > ---
> > > sysdeps/x86_64/multiarch/stpncpy-evex.S | 5 +-
> > > sysdeps/x86_64/multiarch/strcat-evex.S | 291 +---
> > > sysdeps/x86_64/multiarch/strcat-strlen-evex.S | 110 ++
> > > sysdeps/x86_64/multiarch/strcpy-evex.S | 1282 ++++++-----------
> > > sysdeps/x86_64/multiarch/strncat-evex.S | 525 ++++++-
> > > sysdeps/x86_64/multiarch/strncpy-evex.S | 995 ++++++++++++-
> > > .../multiarch/strncpy-or-cat-overflow-def.h | 65 +
> > > 7 files changed, 2100 insertions(+), 1173 deletions(-)
> > > create mode 100644 sysdeps/x86_64/multiarch/strcat-strlen-evex.S
> > > create mode 100644 sysdeps/x86_64/multiarch/strncpy-or-cat-overflow-def.h
> > >
> > > diff --git a/sysdeps/x86_64/multiarch/stpncpy-evex.S b/sysdeps/x86_64/multiarch/stpncpy-evex.S
> > > index 99ea76a372..3693491baa 100644
> > > --- a/sysdeps/x86_64/multiarch/stpncpy-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/stpncpy-evex.S
> > > @@ -3,6 +3,5 @@
> > > #endif
> > >
> > > #define USE_AS_STPCPY
> > > -#define USE_AS_STRNCPY
> > > -#define STRCPY STPNCPY
> > > -#include "strcpy-evex.S"
> > > +#define STRNCPY STPNCPY
> > > +#include "strncpy-evex.S"
> > > diff --git a/sysdeps/x86_64/multiarch/strcat-evex.S b/sysdeps/x86_64/multiarch/strcat-evex.S
> > > index 0e2df947e9..b4207b7889 100644
> > > --- a/sysdeps/x86_64/multiarch/strcat-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/strcat-evex.S
> > > @@ -1,286 +1,7 @@
> > > -/* strcat with 256-bit EVEX instructions.
> > > - Copyright (C) 2021-2022 Free Software Foundation, Inc.
> > > - This file is part of the GNU C Library.
> > > -
> > > - The GNU C Library is free software; you can redistribute it and/or
> > > - modify it under the terms of the GNU Lesser General Public
> > > - License as published by the Free Software Foundation; either
> > > - version 2.1 of the License, or (at your option) any later version.
> > > -
> > > - The GNU C Library is distributed in the hope that it will be useful,
> > > - but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > > - Lesser General Public License for more details.
> > > -
> > > - You should have received a copy of the GNU Lesser General Public
> > > - License along with the GNU C Library; if not, see
> > > - <https://www.gnu.org/licenses/>. */
> > > -
> > > -#include <isa-level.h>
> > > -
> > > -#if ISA_SHOULD_BUILD (4)
> > > -
> > > -
> > > -# include <sysdep.h>
> > > -
> > > -# ifndef STRCAT
> > > -# define STRCAT __strcat_evex
> > > -# endif
> > > -
> > > -# define VMOVU vmovdqu64
> > > -# define VMOVA vmovdqa64
> > > -
> > > -/* zero register */
> > > -# define XMMZERO xmm16
> > > -# define YMMZERO ymm16
> > > -# define YMM0 ymm17
> > > -# define YMM1 ymm18
> > > -
> > > -# define USE_AS_STRCAT
> > > -
> > > -/* Number of bytes in a vector register */
> > > -# define VEC_SIZE 32
> > > -
> > > - .section .text.evex,"ax",@progbits
> > > -ENTRY (STRCAT)
> > > - mov %rdi, %r9
> > > -# ifdef USE_AS_STRNCAT
> > > - mov %rdx, %r8
> > > -# endif
> > > -
> > > - xor %eax, %eax
> > > - mov %edi, %ecx
> > > - and $((VEC_SIZE * 4) - 1), %ecx
> > > - vpxorq %XMMZERO, %XMMZERO, %XMMZERO
> > > - cmp $(VEC_SIZE * 3), %ecx
> > > - ja L(fourth_vector_boundary)
> > > - vpcmpb $0, (%rdi), %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_first_vector)
> > > - mov %rdi, %rax
> > > - and $-VEC_SIZE, %rax
> > > - jmp L(align_vec_size_start)
> > > -L(fourth_vector_boundary):
> > > - mov %rdi, %rax
> > > - and $-VEC_SIZE, %rax
> > > - vpcmpb $0, (%rax), %YMMZERO, %k0
> > > - mov $-1, %r10d
> > > - sub %rax, %rcx
> > > - shl %cl, %r10d
> > > - kmovd %k0, %edx
> > > - and %r10d, %edx
> > > - jnz L(exit)
> > > -
> > > -L(align_vec_size_start):
> > > - vpcmpb $0, VEC_SIZE(%rax), %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_second_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 2)(%rax), %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_third_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 3)(%rax), %YMMZERO, %k2
> > > - kmovd %k2, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fourth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 4)(%rax), %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fifth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 5)(%rax), %YMMZERO, %k4
> > > - add $(VEC_SIZE * 4), %rax
> > > - kmovd %k4, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_second_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 2)(%rax), %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_third_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 3)(%rax), %YMMZERO, %k2
> > > - kmovd %k2, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fourth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 4)(%rax), %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fifth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 5)(%rax), %YMMZERO, %k4
> > > - kmovd %k4, %edx
> > > - add $(VEC_SIZE * 4), %rax
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_second_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 2)(%rax), %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_third_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 3)(%rax), %YMMZERO, %k2
> > > - kmovd %k2, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fourth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 4)(%rax), %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fifth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 5)(%rax), %YMMZERO, %k4
> > > - add $(VEC_SIZE * 4), %rax
> > > - kmovd %k4, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_second_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 2)(%rax), %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_third_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 3)(%rax), %YMMZERO, %k2
> > > - kmovd %k2, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fourth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 4)(%rax), %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fifth_vector)
> > > -
> > > - test $((VEC_SIZE * 4) - 1), %rax
> > > - jz L(align_four_vec_loop)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 5)(%rax), %YMMZERO, %k4
> > > - add $(VEC_SIZE * 5), %rax
> > > - kmovd %k4, %edx
> > > - test %edx, %edx
> > > - jnz L(exit)
> > > -
> > > - test $((VEC_SIZE * 4) - 1), %rax
> > > - jz L(align_four_vec_loop)
> > > -
> > > - vpcmpb $0, VEC_SIZE(%rax), %YMMZERO, %k0
> > > - add $VEC_SIZE, %rax
> > > - kmovd %k0, %edx
> > > - test %edx, %edx
> > > - jnz L(exit)
> > > -
> > > - test $((VEC_SIZE * 4) - 1), %rax
> > > - jz L(align_four_vec_loop)
> > > -
> > > - vpcmpb $0, VEC_SIZE(%rax), %YMMZERO, %k0
> > > - add $VEC_SIZE, %rax
> > > - kmovd %k0, %edx
> > > - test %edx, %edx
> > > - jnz L(exit)
> > > -
> > > - test $((VEC_SIZE * 4) - 1), %rax
> > > - jz L(align_four_vec_loop)
> > > -
> > > - vpcmpb $0, VEC_SIZE(%rax), %YMMZERO, %k1
> > > - add $VEC_SIZE, %rax
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(exit)
> > > -
> > > - add $VEC_SIZE, %rax
> > > -
> > > - .p2align 4
> > > -L(align_four_vec_loop):
> > > - VMOVA (%rax), %YMM0
> > > - VMOVA (VEC_SIZE * 2)(%rax), %YMM1
> > > - vpminub VEC_SIZE(%rax), %YMM0, %YMM0
> > > - vpminub (VEC_SIZE * 3)(%rax), %YMM1, %YMM1
> > > - vpminub %YMM0, %YMM1, %YMM0
> > > - /* If K0 != 0, there is a null byte. */
> > > - vpcmpb $0, %YMM0, %YMMZERO, %k0
> > > - add $(VEC_SIZE * 4), %rax
> > > - ktestd %k0, %k0
> > > - jz L(align_four_vec_loop)
> > > -
> > > - vpcmpb $0, -(VEC_SIZE * 4)(%rax), %YMMZERO, %k0
> > > - sub $(VEC_SIZE * 5), %rax
> > > - kmovd %k0, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_second_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 2)(%rax), %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_third_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 3)(%rax), %YMMZERO, %k2
> > > - kmovd %k2, %edx
> > > - test %edx, %edx
> > > - jnz L(exit_null_on_fourth_vector)
> > > -
> > > - vpcmpb $0, (VEC_SIZE * 4)(%rax), %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - sub %rdi, %rax
> > > - bsf %rdx, %rdx
> > > - add %rdx, %rax
> > > - add $(VEC_SIZE * 4), %rax
> > > - jmp L(StartStrcpyPart)
> > > -
> > > - .p2align 4
> > > -L(exit):
> > > - sub %rdi, %rax
> > > -L(exit_null_on_first_vector):
> > > - bsf %rdx, %rdx
> > > - add %rdx, %rax
> > > - jmp L(StartStrcpyPart)
> > > -
> > > - .p2align 4
> > > -L(exit_null_on_second_vector):
> > > - sub %rdi, %rax
> > > - bsf %rdx, %rdx
> > > - add %rdx, %rax
> > > - add $VEC_SIZE, %rax
> > > - jmp L(StartStrcpyPart)
> > > -
> > > - .p2align 4
> > > -L(exit_null_on_third_vector):
> > > - sub %rdi, %rax
> > > - bsf %rdx, %rdx
> > > - add %rdx, %rax
> > > - add $(VEC_SIZE * 2), %rax
> > > - jmp L(StartStrcpyPart)
> > > -
> > > - .p2align 4
> > > -L(exit_null_on_fourth_vector):
> > > - sub %rdi, %rax
> > > - bsf %rdx, %rdx
> > > - add %rdx, %rax
> > > - add $(VEC_SIZE * 3), %rax
> > > - jmp L(StartStrcpyPart)
> > > -
> > > - .p2align 4
> > > -L(exit_null_on_fifth_vector):
> > > - sub %rdi, %rax
> > > - bsf %rdx, %rdx
> > > - add %rdx, %rax
> > > - add $(VEC_SIZE * 4), %rax
> > > -
> > > - .p2align 4
> > > -L(StartStrcpyPart):
> > > - lea (%r9, %rax), %rdi
> > > - mov %rsi, %rcx
> > > - mov %r9, %rax /* save result */
> > > -
> > > -# ifdef USE_AS_STRNCAT
> > > - test %r8, %r8
> > > - jz L(ExitZero)
> > > -# define USE_AS_STRNCPY
> > > -# endif
> > > -
> > > -# include "strcpy-evex.S"
> > > +#ifndef STRCAT
> > > +# define STRCAT __strcat_evex
> > > #endif
> > > +
> > > +#define USE_AS_STRCAT
> > > +#define STRCPY STRCAT
> > > +#include "strcpy-evex.S"
> > > diff --git a/sysdeps/x86_64/multiarch/strcat-strlen-evex.S b/sysdeps/x86_64/multiarch/strcat-strlen-evex.S
> > > new file mode 100644
> > > index 0000000000..9530d7b683
> > > --- /dev/null
> > > +++ b/sysdeps/x86_64/multiarch/strcat-strlen-evex.S
> > > @@ -0,0 +1,110 @@
> > > +/* strlen used for begining of str{n}cat using EVEX 256/512.
> > > + Copyright (C) 2011-2022 Free Software Foundation, Inc.
> > > + This file is part of the GNU C Library.
> > > +
> > > + The GNU C Library is free software; you can redistribute it and/or
> > > + modify it under the terms of the GNU Lesser General Public
> > > + License as published by the Free Software Foundation; either
> > > + version 2.1 of the License, or (at your option) any later version.
> > > +
> > > + The GNU C Library is distributed in the hope that it will be useful,
> > > + but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > > + Lesser General Public License for more details.
> > > +
> > > + You should have received a copy of the GNU Lesser General Public
> > > + License along with the GNU C Library; if not, see
> > > + <https://www.gnu.org/licenses/>. */
> > > +
> > > +
> > > +/* NOTE: This file is meant to be included by strcat-evex or
> > > + strncat-evex and does not standalone. Before including %rdi
> > > + must be saved in %rax. */
> >
> > Since this file isn't standalone, please rename it to .h.
>
> Can it be .h.S so it plays well it IDE modes?
It sounds reasonable.
> >
> > > +
> > > +
> > > +/* Simple strlen implementation that ends at
> > > + L(strcat_strlen_done). */
> > > + vpxorq %VZERO_128, %VZERO_128, %VZERO_128
> > > + movq %rdi, %r8
> > > + andq $(VEC_SIZE * -1), %r8
> > > + VPCMPEQ (%r8), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > +#ifdef USE_AS_WCSCPY
> > > + subl %r8d, %edi
> > > + shrl $2, %edi
> > > +#endif
> > > + shrx %VRDI, %VRCX, %VRCX
> > > +#ifdef USE_AS_WCSCPY
> > > + movq %rax, %rdi
> > > +#endif
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v0)
> > > +
> > > +
> > > + VPCMPEQ VEC_SIZE(%r8), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > + leaq (VEC_SIZE)(%r8), %rdi
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v0)
> > > +
> > > + VPCMPEQ (VEC_SIZE * 2)(%r8), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v1)
> > > +
> > > + VPCMPEQ (VEC_SIZE * 3)(%r8), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v2)
> > > +
> > > + VPCMPEQ (VEC_SIZE * 4)(%r8), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v3)
> > > +
> > > + andq $-(VEC_SIZE * 4), %rdi
> > > + .p2align 4,, 8
> > > +L(loop_2x_vec):
> > > + VMOVA (VEC_SIZE * 4)(%rdi), %VMM(0)
> > > + VPMIN (VEC_SIZE * 5)(%rdi), %VMM(0), %VMM(1)
> > > + VMOVA (VEC_SIZE * 6)(%rdi), %VMM(2)
> > > + VPMIN (VEC_SIZE * 7)(%rdi), %VMM(2), %VMM(3)
> > > + VPTESTN %VMM(1), %VMM(1), %k1
> > > + VPTESTN %VMM(3), %VMM(3), %k3
> > > + subq $(VEC_SIZE * -4), %rdi
> > > + KORTEST %k1, %k3
> > > + jz L(loop_2x_vec)
> > > +
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v0)
> > > +
> > > + KMOV %k1, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v1)
> > > +
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(bsf_and_done_v2)
> > > +
> > > + KMOV %k3, %VRCX
> > > +L(bsf_and_done_v3):
> > > + addq $VEC_SIZE, %rdi
> > > +L(bsf_and_done_v2):
> > > + bsf %VRCX, %VRCX
> > > + leaq (VEC_SIZE * 2)(%rdi, %rcx, CHAR_SIZE), %rdi
> > > + jmp L(strcat_strlen_done)
> > > +
> > > + .p2align 4,, 4
> > > +L(bsf_and_done_v1):
> > > + addq $VEC_SIZE, %rdi
> > > +L(bsf_and_done_v0):
> > > + bsf %VRCX, %VRCX
> > > +#ifdef USE_AS_WCSCPY
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rdi
> > > +#else
> > > + addq %rcx, %rdi
> > > +#endif
> > > +L(strcat_strlen_done):
> > > diff --git a/sysdeps/x86_64/multiarch/strcpy-evex.S b/sysdeps/x86_64/multiarch/strcpy-evex.S
> > > index 82e45ac675..1ba0195ed2 100644
> > > --- a/sysdeps/x86_64/multiarch/strcpy-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/strcpy-evex.S
> > > @@ -1,4 +1,4 @@
> > > -/* strcpy with 256-bit EVEX instructions.
> > > +/* {wcs|wcp|str|stp}cpy with 256/512-bit EVEX instructions.
> > > Copyright (C) 2021-2022 Free Software Foundation, Inc.
> > > This file is part of the GNU C Library.
> > >
> > > @@ -17,990 +17,526 @@
> > > <https://www.gnu.org/licenses/>. */
> > >
> > > #include <isa-level.h>
> > > -
> > > #if ISA_SHOULD_BUILD (4)
> > >
> > >
> > > -# ifndef USE_AS_STRCAT
> > > -# include <sysdep.h>
> > > + /* Use evex-masked stores for small sizes. Turned off at the
> > > + moment. */
> > > +# define USE_EVEX_MASKED_STORE 0
> > > + /* Use movsb in page cross case to save code size. */
> > > +# define USE_MOVSB_IN_PAGE_CROSS 1
> > >
> > > -# ifndef STRCPY
> > > -# define STRCPY __strcpy_evex
> > > -# endif
> > > +# include <sysdep.h>
> > >
> > > +# ifndef VEC_SIZE
> > > +# include "x86-evex256-vecs.h"
> > > # endif
> > >
> > > -# define VMOVU vmovdqu64
> > > -# define VMOVA vmovdqa64
> > > -
> > > -/* Number of bytes in a vector register */
> > > -# ifndef VEC_SIZE
> > > -# define VEC_SIZE 32
> > > +# ifndef STRCPY
> > > +# define STRCPY __strcpy_evex
> > > # endif
> > >
> > > -# define XMM2 xmm18
> > > -# define XMM3 xmm19
> > >
> > > -# define YMM2 ymm18
> > > -# define YMM3 ymm19
> > > -# define YMM4 ymm20
> > > -# define YMM5 ymm21
> > > -# define YMM6 ymm22
> > > -# define YMM7 ymm23
> > > +# ifdef USE_AS_WCSCPY
> > > +# define VMOVU_MASK vmovdqu32
> > > +# define VPMIN vpminud
> > > +# define VPTESTN vptestnmd
> > > +# define VPTEST vptestmd
> > > +# define VPCMPEQ vpcmpeqd
> > > +# define CHAR_SIZE 4
> > >
> > > -# ifndef USE_AS_STRCAT
> > > +# define REP_MOVS rep movsd
> > >
> > > -/* zero register */
> > > -# define XMMZERO xmm16
> > > -# define YMMZERO ymm16
> > > -# define YMM1 ymm17
> > > -
> > > - .section .text.evex,"ax",@progbits
> > > -ENTRY (STRCPY)
> > > -# ifdef USE_AS_STRNCPY
> > > - mov %RDX_LP, %R8_LP
> > > - test %R8_LP, %R8_LP
> > > - jz L(ExitZero)
> > > -# endif
> > > - mov %rsi, %rcx
> > > -# ifndef USE_AS_STPCPY
> > > - mov %rdi, %rax /* save result */
> > > -# endif
> > > +# define USE_WIDE_CHAR
> > > +# else
> > > +# define VMOVU_MASK vmovdqu8
> > > +# define VPMIN vpminub
> > > +# define VPTESTN vptestnmb
> > > +# define VPTEST vptestmb
> > > +# define VPCMPEQ vpcmpeqb
> > > +# define CHAR_SIZE 1
> > >
> > > - vpxorq %XMMZERO, %XMMZERO, %XMMZERO
> > > +# define REP_MOVS rep movsb
> > > # endif
> > >
> > > - and $((VEC_SIZE * 4) - 1), %ecx
> > > - cmp $(VEC_SIZE * 2), %ecx
> > > - jbe L(SourceStringAlignmentLessTwoVecSize)
> > > -
> > > - and $-VEC_SIZE, %rsi
> > > - and $(VEC_SIZE - 1), %ecx
> > > -
> > > - vpcmpb $0, (%rsi), %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - shr %cl, %rdx
> > > +# include "reg-macros.h"
> > >
> > > -# ifdef USE_AS_STRNCPY
> > > -# if defined USE_AS_STPCPY || defined USE_AS_STRCAT
> > > - mov $VEC_SIZE, %r10
> > > - sub %rcx, %r10
> > > - cmp %r10, %r8
> > > -# else
> > > - mov $(VEC_SIZE + 1), %r10
> > > - sub %rcx, %r10
> > > - cmp %r10, %r8
> > > -# endif
> > > - jbe L(CopyVecSizeTailCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > - jnz L(CopyVecSizeTail)
> > > -
> > > - vpcmpb $0, VEC_SIZE(%rsi), %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > >
> > > -# ifdef USE_AS_STRNCPY
> > > - add $VEC_SIZE, %r10
> > > - cmp %r10, %r8
> > > - jbe L(CopyTwoVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > - jnz L(CopyTwoVecSize)
> > > -
> > > - VMOVU (%rsi, %rcx), %YMM2 /* copy VEC_SIZE bytes */
> > > - VMOVU %YMM2, (%rdi)
> > > -
> > > -/* If source address alignment != destination address alignment */
> > > - .p2align 4
> > > -L(UnalignVecSizeBoth):
> > > - sub %rcx, %rdi
> > > -# ifdef USE_AS_STRNCPY
> > > - add %rcx, %r8
> > > - sbb %rcx, %rcx
> > > - or %rcx, %r8
> > > -# endif
> > > - mov $VEC_SIZE, %rcx
> > > - VMOVA (%rsi, %rcx), %YMM2
> > > - VMOVU %YMM2, (%rdi, %rcx)
> > > - VMOVA VEC_SIZE(%rsi, %rcx), %YMM2
> > > - vpcmpb $0, %YMM2, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - add $VEC_SIZE, %rcx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $(VEC_SIZE * 3), %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec2)
> > > +# ifdef USE_AS_STPCPY
> > > +# define END_REG rax
> > > # else
> > > - jnz L(CopyVecSize)
> > > +# define END_REG rdi, %rdx, CHAR_SIZE
> > > # endif
> > >
> > > - VMOVU %YMM2, (%rdi, %rcx)
> > > - VMOVA VEC_SIZE(%rsi, %rcx), %YMM3
> > > - vpcmpb $0, %YMM3, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - add $VEC_SIZE, %rcx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec3)
> > > +# ifdef USE_AS_STRCAT
> > > +# define PAGE_ALIGN_REG edx
> > > +# define PAGE_ALIGN_REG_64 rdx
> > > # else
> > > - jnz L(CopyVecSize)
> > > +# define PAGE_ALIGN_REG eax
> > > +# define PAGE_ALIGN_REG_64 rax
> > > # endif
> > >
> > > - VMOVU %YMM3, (%rdi, %rcx)
> > > - VMOVA VEC_SIZE(%rsi, %rcx), %YMM4
> > > - vpcmpb $0, %YMM4, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - add $VEC_SIZE, %rcx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec4)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > -# endif
> > > +# define VZERO VMM(7)
> > > +# define VZERO_128 VMM_128(7)
> > >
> > > - VMOVU %YMM4, (%rdi, %rcx)
> > > - VMOVA VEC_SIZE(%rsi, %rcx), %YMM2
> > > - vpcmpb $0, %YMM2, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - add $VEC_SIZE, %rcx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec2)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > -# endif
> > >
> > > - VMOVU %YMM2, (%rdi, %rcx)
> > > - VMOVA VEC_SIZE(%rsi, %rcx), %YMM2
> > > - vpcmpb $0, %YMM2, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - add $VEC_SIZE, %rcx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec2)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > -# endif
> > > +# define PAGE_SIZE 4096
> > > +# define CHAR_PER_VEC (VEC_SIZE / CHAR_SIZE)
> > >
> > > - VMOVA VEC_SIZE(%rsi, %rcx), %YMM3
> > > - VMOVU %YMM2, (%rdi, %rcx)
> > > - vpcmpb $0, %YMM3, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > - add $VEC_SIZE, %rcx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec3)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > -# endif
> > >
> > > - VMOVU %YMM3, (%rdi, %rcx)
> > > - mov %rsi, %rdx
> > > - lea VEC_SIZE(%rsi, %rcx), %rsi
> > > - and $-(VEC_SIZE * 4), %rsi
> > > - sub %rsi, %rdx
> > > - sub %rdx, %rdi
> > > -# ifdef USE_AS_STRNCPY
> > > - lea (VEC_SIZE * 8)(%r8, %rdx), %r8
> > > -# endif
> > > -L(UnalignedFourVecSizeLoop):
> > > - VMOVA (%rsi), %YMM4
> > > - VMOVA VEC_SIZE(%rsi), %YMM5
> > > - VMOVA (VEC_SIZE * 2)(%rsi), %YMM6
> > > - VMOVA (VEC_SIZE * 3)(%rsi), %YMM7
> > > - vpminub %YMM5, %YMM4, %YMM2
> > > - vpminub %YMM7, %YMM6, %YMM3
> > > - vpminub %YMM2, %YMM3, %YMM2
> > > - /* If K7 != 0, there is a null byte. */
> > > - vpcmpb $0, %YMM2, %YMMZERO, %k7
> > > - kmovd %k7, %edx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $(VEC_SIZE * 4), %r8
> > > - jbe L(UnalignedLeaveCase2OrCase3)
> > > + .section SECTION(.text), "ax", @progbits
> > > +ENTRY(STRCPY)
> > > +# ifdef USE_AS_STRCAT
> > > + movq %rdi, %rax
> > > +# include "strcat-strlen-evex.S"
> > > # endif
> > > - test %edx, %edx
> > > - jnz L(UnalignedFourVecSizeLeave)
> > > -
> > > -L(UnalignedFourVecSizeLoop_start):
> > > - add $(VEC_SIZE * 4), %rdi
> > > - add $(VEC_SIZE * 4), %rsi
> > > - VMOVU %YMM4, -(VEC_SIZE * 4)(%rdi)
> > > - VMOVA (%rsi), %YMM4
> > > - VMOVU %YMM5, -(VEC_SIZE * 3)(%rdi)
> > > - VMOVA VEC_SIZE(%rsi), %YMM5
> > > - vpminub %YMM5, %YMM4, %YMM2
> > > - VMOVU %YMM6, -(VEC_SIZE * 2)(%rdi)
> > > - VMOVA (VEC_SIZE * 2)(%rsi), %YMM6
> > > - VMOVU %YMM7, -VEC_SIZE(%rdi)
> > > - VMOVA (VEC_SIZE * 3)(%rsi), %YMM7
> > > - vpminub %YMM7, %YMM6, %YMM3
> > > - vpminub %YMM2, %YMM3, %YMM2
> > > - /* If K7 != 0, there is a null byte. */
> > > - vpcmpb $0, %YMM2, %YMMZERO, %k7
> > > - kmovd %k7, %edx
> > > -# ifdef USE_AS_STRNCPY
> > > - sub $(VEC_SIZE * 4), %r8
> > > - jbe L(UnalignedLeaveCase2OrCase3)
> > > +
> > > + movl %esi, %PAGE_ALIGN_REG
> > > + andl $(PAGE_SIZE - 1), %PAGE_ALIGN_REG
> > > + cmpl $(PAGE_SIZE - VEC_SIZE), %PAGE_ALIGN_REG
> > > + ja L(page_cross)
> > > +L(page_cross_continue):
> > > + VMOVU (%rsi), %VMM(0)
> > > +# if !defined USE_AS_STPCPY && !defined USE_AS_STRCAT
> > > + movq %rdi, %rax
> > > # endif
> > > - test %edx, %edx
> > > - jz L(UnalignedFourVecSizeLoop_start)
> > >
> > > -L(UnalignedFourVecSizeLeave):
> > > - vpcmpb $0, %YMM4, %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - test %edx, %edx
> > > - jnz L(CopyVecSizeUnaligned_0)
> > >
> > > - vpcmpb $0, %YMM5, %YMMZERO, %k2
> > > - kmovd %k2, %ecx
> > > - test %ecx, %ecx
> > > - jnz L(CopyVecSizeUnaligned_16)
> > > + /* Two short string implementations. One with traditional
> > > + branching approach and one with masked instructions (which
> > > + have potential for dramatically bad perf if dst splits a
> > > + page and is not in the TLB). */
> > > +# if USE_EVEX_MASKED_STORE
> > > + VPTEST %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > +# ifdef USE_AS_WCSCPY
> > > + subl $((1 << CHAR_PER_VEC)- 1), %VRCX
> > > +# else
> > > + inc %VRCX
> > > +# endif
> > > + jz L(more_1x_vec)
> > > + KMOV %VRCX, %k1
> > > + KXOR %k0, %k1, %k1
> > >
> > > - vpcmpb $0, %YMM6, %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - test %edx, %edx
> > > - jnz L(CopyVecSizeUnaligned_32)
> > > -
> > > - vpcmpb $0, %YMM7, %YMMZERO, %k4
> > > - kmovd %k4, %ecx
> > > - bsf %ecx, %edx
> > > - VMOVU %YMM4, (%rdi)
> > > - VMOVU %YMM5, VEC_SIZE(%rdi)
> > > - VMOVU %YMM6, (VEC_SIZE * 2)(%rdi)
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > -# ifdef USE_AS_STPCPY
> > > - lea (VEC_SIZE * 3)(%rdi, %rdx), %rax
> > > -# endif
> > > - VMOVU %YMM7, (VEC_SIZE * 3)(%rdi)
> > > - add $(VEC_SIZE - 1), %r8
> > > - sub %rdx, %r8
> > > - lea ((VEC_SIZE * 3) + 1)(%rdi, %rdx), %rdi
> > > - jmp L(StrncpyFillTailWithZero)
> > > -# else
> > > - add $(VEC_SIZE * 3), %rsi
> > > - add $(VEC_SIZE * 3), %rdi
> > > - jmp L(CopyVecSizeExit)
> > > -# endif
> > > + VMOVU_MASK %VMM(0), (%rdi){%k1}
> > >
> > > -/* If source address alignment == destination address alignment */
> > > +# ifdef USE_AS_STPCPY
> > > + bsf %VRCX, %VRCX
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rax
> > > +# endif
> > > + ret
> > >
> > > -L(SourceStringAlignmentLessTwoVecSize):
> > > - VMOVU (%rsi), %YMM3
> > > - VMOVU VEC_SIZE(%rsi), %YMM2
> > > - vpcmpb $0, %YMM3, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > > +# else
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jz L(more_1x_vec)
> > >
> > > -# ifdef USE_AS_STRNCPY
> > > -# if defined USE_AS_STPCPY || defined USE_AS_STRCAT
> > > - cmp $VEC_SIZE, %r8
> > > + xorl %edx, %edx
> > > + bsf %VRCX, %VRDX
> > > +# ifdef USE_AS_STPCPY
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# endif
> > > +
> > > + /* Use mask bits in rcx to detect which copy we need. If the low
> > > + mask is zero then there must be a bit set in the upper half.
> > > + I.e if rcx != 0 and ecx == 0, then match must be upper 32
> > > + bits so we use L(copy_32_63). */
> > > +# if VEC_SIZE == 64
> > > +# ifdef USE_AS_WCSCPY
> > > + testb %cl, %cl
> > > +# else
> > > + testl %ecx, %ecx
> > > +# endif
> > > + jz L(copy_32_63)
> > > +# endif
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > + testb $0xf, %cl
> > > # else
> > > - cmp $(VEC_SIZE + 1), %r8
> > > + testw %cx, %cx
> > > # endif
> > > - jbe L(CopyVecSizeTail1Case2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > - jnz L(CopyVecSizeTail1)
> > > + jz L(copy_16_31)
> > >
> > > - VMOVU %YMM3, (%rdi)
> > > - vpcmpb $0, %YMM2, %YMMZERO, %k0
> > > - kmovd %k0, %edx
> > >
> > > -# ifdef USE_AS_STRNCPY
> > > -# if defined USE_AS_STPCPY || defined USE_AS_STRCAT
> > > - cmp $(VEC_SIZE * 2), %r8
> > > +# ifdef USE_AS_WCSCPY
> > > + testb $0x3, %cl
> > > # else
> > > - cmp $((VEC_SIZE * 2) + 1), %r8
> > > + testb %cl, %cl
> > > # endif
> > > - jbe L(CopyTwoVecSize1Case2OrCase3)
> > > -# endif
> > > - test %edx, %edx
> > > - jnz L(CopyTwoVecSize1)
> > > -
> > > - and $-VEC_SIZE, %rsi
> > > - and $(VEC_SIZE - 1), %ecx
> > > - jmp L(UnalignVecSizeBoth)
> > > + jz L(copy_8_15)
> > >
> > > -/*------End of main part with loops---------------------*/
> > >
> > > -/* Case1 */
> > > +# ifdef USE_AS_WCSCPY
> > > + vmovd %VMM_128(0), (%rdi)
> > > + /* No need to copy, we know its zero. */
> > > + movl $0, (%END_REG)
> > >
> > > -# if (!defined USE_AS_STRNCPY) || (defined USE_AS_STRCAT)
> > > - .p2align 4
> > > -L(CopyVecSize):
> > > - add %rcx, %rdi
> > > -# endif
> > > -L(CopyVecSizeTail):
> > > - add %rcx, %rsi
> > > -L(CopyVecSizeTail1):
> > > - bsf %edx, %edx
> > > -L(CopyVecSizeExit):
> > > - cmp $32, %edx
> > > - jae L(Exit32_63)
> > > - cmp $16, %edx
> > > - jae L(Exit16_31)
> > > - cmp $8, %edx
> > > - jae L(Exit8_15)
> > > - cmp $4, %edx
> > > - jae L(Exit4_7)
> > > - cmp $3, %edx
> > > - je L(Exit3)
> > > - cmp $1, %edx
> > > - ja L(Exit2)
> > > - je L(Exit1)
> > > - movb $0, (%rdi)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi), %rax
> > > -# endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub $1, %r8
> > > - lea 1(%rdi), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > -# endif
> > > ret
> > > +# else
> > >
> > > - .p2align 4
> > > -L(CopyTwoVecSize1):
> > > - add $VEC_SIZE, %rsi
> > > - add $VEC_SIZE, %rdi
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub $VEC_SIZE, %r8
> > > -# endif
> > > - jmp L(CopyVecSizeTail1)
> > > -
> > > - .p2align 4
> > > -L(CopyTwoVecSize):
> > > - bsf %edx, %edx
> > > - add %rcx, %rsi
> > > - add $VEC_SIZE, %edx
> > > - sub %ecx, %edx
> > > - jmp L(CopyVecSizeExit)
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeUnaligned_0):
> > > - bsf %edx, %edx
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %rdx), %rax
> > > -# endif
> > > - VMOVU %YMM4, (%rdi)
> > > - add $((VEC_SIZE * 4) - 1), %r8
> > > - sub %rdx, %r8
> > > - lea 1(%rdi, %rdx), %rdi
> > > - jmp L(StrncpyFillTailWithZero)
> > > -# else
> > > - jmp L(CopyVecSizeExit)
> > > -# endif
> > > + testb $0x7, %cl
> > > + jz L(copy_4_7)
> > >
> > > - .p2align 4
> > > -L(CopyVecSizeUnaligned_16):
> > > - bsf %ecx, %edx
> > > - VMOVU %YMM4, (%rdi)
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > -# ifdef USE_AS_STPCPY
> > > - lea VEC_SIZE(%rdi, %rdx), %rax
> > > -# endif
> > > - VMOVU %YMM5, VEC_SIZE(%rdi)
> > > - add $((VEC_SIZE * 3) - 1), %r8
> > > - sub %rdx, %r8
> > > - lea (VEC_SIZE + 1)(%rdi, %rdx), %rdi
> > > - jmp L(StrncpyFillTailWithZero)
> > > -# else
> > > - add $VEC_SIZE, %rsi
> > > - add $VEC_SIZE, %rdi
> > > - jmp L(CopyVecSizeExit)
> > > -# endif
> > >
> > > - .p2align 4
> > > -L(CopyVecSizeUnaligned_32):
> > > - bsf %edx, %edx
> > > - VMOVU %YMM4, (%rdi)
> > > - VMOVU %YMM5, VEC_SIZE(%rdi)
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > -# ifdef USE_AS_STPCPY
> > > - lea (VEC_SIZE * 2)(%rdi, %rdx), %rax
> > > -# endif
> > > - VMOVU %YMM6, (VEC_SIZE * 2)(%rdi)
> > > - add $((VEC_SIZE * 2) - 1), %r8
> > > - sub %rdx, %r8
> > > - lea ((VEC_SIZE * 2) + 1)(%rdi, %rdx), %rdi
> > > - jmp L(StrncpyFillTailWithZero)
> > > -# else
> > > - add $(VEC_SIZE * 2), %rsi
> > > - add $(VEC_SIZE * 2), %rdi
> > > - jmp L(CopyVecSizeExit)
> > > -# endif
> > > + test %edx, %edx
> > > + jz L(set_null_term)
> > >
> > > -# ifdef USE_AS_STRNCPY
> > > -# ifndef USE_AS_STRCAT
> > > - .p2align 4
> > > -L(CopyVecSizeUnalignedVec6):
> > > - VMOVU %YMM6, (%rdi, %rcx)
> > > - jmp L(CopyVecSizeVecExit)
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeUnalignedVec5):
> > > - VMOVU %YMM5, (%rdi, %rcx)
> > > - jmp L(CopyVecSizeVecExit)
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeUnalignedVec4):
> > > - VMOVU %YMM4, (%rdi, %rcx)
> > > - jmp L(CopyVecSizeVecExit)
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeUnalignedVec3):
> > > - VMOVU %YMM3, (%rdi, %rcx)
> > > - jmp L(CopyVecSizeVecExit)
> > > + /* NB: make this `vmovw` if support for AVX512-FP16 is added.
> > > + */
> > > + vmovd %VMM_128(0), %esi
> > > + movw %si, (%rdi)
> > > +
> > > + .p2align 4,, 1
> > > +L(set_null_term):
> > > + /* No need to copy, we know its zero. */
> > > + movb $0, (%END_REG)
> > > + ret
> > > # endif
> > >
> > > -/* Case2 */
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeCase2):
> > > - add $VEC_SIZE, %r8
> > > - add %rcx, %rdi
> > > - add %rcx, %rsi
> > > - bsf %edx, %edx
> > > - cmp %r8d, %edx
> > > - jb L(CopyVecSizeExit)
> > > - jmp L(StrncpyExit)
> > > -
> > > - .p2align 4
> > > -L(CopyTwoVecSizeCase2):
> > > - add %rcx, %rsi
> > > - bsf %edx, %edx
> > > - add $VEC_SIZE, %edx
> > > - sub %ecx, %edx
> > > - cmp %r8d, %edx
> > > - jb L(CopyVecSizeExit)
> > > - jmp L(StrncpyExit)
> > > -
> > > -L(CopyVecSizeTailCase2):
> > > - add %rcx, %rsi
> > > - bsf %edx, %edx
> > > - cmp %r8d, %edx
> > > - jb L(CopyVecSizeExit)
> > > - jmp L(StrncpyExit)
> > > -
> > > -L(CopyVecSizeTail1Case2):
> > > - bsf %edx, %edx
> > > - cmp %r8d, %edx
> > > - jb L(CopyVecSizeExit)
> > > - jmp L(StrncpyExit)
> > > -
> > > -/* Case2 or Case3, Case3 */
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeCase2OrCase3):
> > > - test %rdx, %rdx
> > > - jnz L(CopyVecSizeCase2)
> > > -L(CopyVecSizeCase3):
> > > - add $VEC_SIZE, %r8
> > > - add %rcx, %rdi
> > > - add %rcx, %rsi
> > > - jmp L(StrncpyExit)
> > > -
> > > - .p2align 4
> > > -L(CopyTwoVecSizeCase2OrCase3):
> > > - test %rdx, %rdx
> > > - jnz L(CopyTwoVecSizeCase2)
> > > - add %rcx, %rsi
> > > - jmp L(StrncpyExit)
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeTailCase2OrCase3):
> > > - test %rdx, %rdx
> > > - jnz L(CopyVecSizeTailCase2)
> > > - add %rcx, %rsi
> > > - jmp L(StrncpyExit)
> > > -
> > > - .p2align 4
> > > -L(CopyTwoVecSize1Case2OrCase3):
> > > - add $VEC_SIZE, %rdi
> > > - add $VEC_SIZE, %rsi
> > > - sub $VEC_SIZE, %r8
> > > -L(CopyVecSizeTail1Case2OrCase3):
> > > - test %rdx, %rdx
> > > - jnz L(CopyVecSizeTail1Case2)
> > > - jmp L(StrncpyExit)
> > > +# if VEC_SIZE == 64
> > > + .p2align 4,, 6
> > > +L(copy_32_63):
> > > + VMOVU -(32 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %VMM_256(1)
> > > + VMOVU %VMM_256(0), (%rdi)
> > > + VMOVU %VMM_256(1), -(32 - CHAR_SIZE)(%END_REG)
> > > + ret
> > > +# endif
> > > +
> > > +
> > > + .p2align 4,, 6
> > > +L(copy_16_31):
> > > + /* Use xmm1 explicitly here as it won't require a `vzeroupper`
> > > + and will save code size. */
> > > + vmovdqu -(16 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %xmm1
> > > + VMOVU %VMM_128(0), (%rdi)
> > > + vmovdqu %xmm1, -(16 - CHAR_SIZE)(%END_REG)
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(copy_8_15):
> > > +# ifdef USE_AS_WCSCPY
> > > + movl -(8 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %ecx
> > > +# else
> > > + movq -(8 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %rcx
> > > +# endif
> > > + vmovq %VMM_128(0), (%rdi)
> > > + movq %rcx, -(8 - CHAR_SIZE)(%END_REG)
> > > + ret
> > > # endif
> > >
> > > -/*------------End labels regarding with copying 1-VEC_SIZE bytes--and 1-(VEC_SIZE*2) bytes----*/
> > >
> > > - .p2align 4
> > > -L(Exit1):
> > > - movzwl (%rsi), %edx
> > > - mov %dx, (%rdi)
> > > -# ifdef USE_AS_STPCPY
> > > - lea 1(%rdi), %rax
> > > +# ifndef USE_AS_WCSCPY
> > > + .p2align 4,, 12
> > > +L(copy_4_7):
> > > + movl -(4 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %ecx
> > > + vmovd %VMM_128(0), (%rdi)
> > > + movl %ecx, -(4 - CHAR_SIZE)(%END_REG)
> > > + ret
> > > # endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub $2, %r8
> > > - lea 2(%rdi), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > +
> > > +
> > > + .p2align 4,, 8
> > > +L(more_1x_vec):
> > > +# if defined USE_AS_STPCPY || defined USE_AS_STRCAT
> > > + VMOVU %VMM(0), (%rdi)
> > > # endif
> > > - ret
> > > + subq %rsi, %rdi
> > > + andq $-(VEC_SIZE), %rsi
> > > + addq %rsi, %rdi
> > > + VMOVA (VEC_SIZE * 1)(%rsi), %VMM(1)
> > >
> > > - .p2align 4
> > > -L(Exit2):
> > > - movzwl (%rsi), %ecx
> > > - mov %cx, (%rdi)
> > > - movb $0, 2(%rdi)
> > > + /* Ideally we store after moves to minimize impact of potential
> > > + false-dependencies. */
> > > +# if !defined USE_AS_STPCPY && !defined USE_AS_STRCAT
> > > + VMOVU %VMM(0), (%rax)
> > > +# endif
> > > +
> > > + VPTESTN %VMM(1), %VMM(1), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x1)
> > > +
> > > + VMOVA (VEC_SIZE * 2)(%rsi), %VMM(2)
> > > + VMOVU %VMM(1), VEC_SIZE(%rdi)
> > > +
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x2)
> > > +
> > > + VMOVA (VEC_SIZE * 3)(%rsi), %VMM(3)
> > > + VMOVU %VMM(2), (VEC_SIZE * 2)(%rdi)
> > > +
> > > + VPTESTN %VMM(3), %VMM(3), %k0
> > > + KMOV %k0, %VRDX
> > > + test %VRDX, %VRDX
> > > + jnz L(ret_vec_x3)
> > > +
> > > + VMOVA (VEC_SIZE * 4)(%rsi), %VMM(4)
> > > + VMOVU %VMM(3), (VEC_SIZE * 3)(%rdi)
> > > + VPTESTN %VMM(4), %VMM(4), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x4)
> > > +
> > > + VMOVU %VMM(4), (VEC_SIZE * 4)(%rdi)
> > > +
> > > +
> > > + /* Align for 4x loop. */
> > > + subq %rsi, %rdi
> > > +
> > > + /* + VEC_SIZE * 5 because we never added the original VEC_SIZE
> > > + we covered before aligning. */
> > > + subq $-(VEC_SIZE * 5), %rsi
> > > + andq $-(VEC_SIZE * 4), %rsi
> > > +
> > > +
> > > + /* Load first half of the loop before entry. */
> > > + VMOVA (VEC_SIZE * 0 + 0)(%rsi), %VMM(0)
> > > + VMOVA (VEC_SIZE * 1 + 0)(%rsi), %VMM(1)
> > > + VMOVA (VEC_SIZE * 2 + 0)(%rsi), %VMM(2)
> > > + VMOVA (VEC_SIZE * 3 + 0)(%rsi), %VMM(3)
> > > +
> > > + VPMIN %VMM(0), %VMM(1), %VMM(4)
> > > + VPMIN %VMM(2), %VMM(3), %VMM(6)
> > > + VPTESTN %VMM(4), %VMM(4), %k2
> > > + VPTESTN %VMM(6), %VMM(6), %k4
> > > + KORTEST %k2, %k4
> > > + jnz L(loop_4x_done)
> > > +
> > > + .p2align 4,, 11
> > > +L(loop_4x_vec):
> > > +
> > > + VMOVU %VMM(0), (VEC_SIZE * 0 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(1), (VEC_SIZE * 1 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(2), (VEC_SIZE * 2 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(3), (VEC_SIZE * 3 + 0)(%rdi, %rsi)
> > > +
> > > + subq $(VEC_SIZE * -4), %rsi
> > > +
> > > + VMOVA (VEC_SIZE * 0 + 0)(%rsi), %VMM(0)
> > > + VMOVA (VEC_SIZE * 1 + 0)(%rsi), %VMM(1)
> > > + VMOVA (VEC_SIZE * 2 + 0)(%rsi), %VMM(2)
> > > + VMOVA (VEC_SIZE * 3 + 0)(%rsi), %VMM(3)
> > > +
> > > +
> > > + VPMIN %VMM(0), %VMM(1), %VMM(4)
> > > + VPMIN %VMM(2), %VMM(3), %VMM(6)
> > > + VPTESTN %VMM(4), %VMM(4), %k2
> > > + VPTESTN %VMM(6), %VMM(6), %k4
> > > + KORTEST %k2, %k4
> > > + jz L(loop_4x_vec)
> > > +
> > > +L(loop_4x_done):
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > + /* Restore rdi (%rdi). */
> > > + addq %rsi, %rdi
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x0_end)
> > > + VMOVU %VMM(0), (VEC_SIZE * 0 + 0)(%rdi)
> > > +
> > > + KMOV %k2, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x1)
> > > + VMOVU %VMM(1), (VEC_SIZE * 1 + 0)(%rdi)
> > > +
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x2)
> > > + VMOVU %VMM(2), (VEC_SIZE * 2 + 0)(%rdi)
> > > + /* Place L(ret_vec_x4) here to save code size. We get a
> > > + meaningfuly benefit doing this for stpcpy. */
> > > + KMOV %k4, %VRDX
> > > +L(ret_vec_x3):
> > > + bsf %VRDX, %VRDX
> > > + VMOVU ((VEC_SIZE * 3)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rdx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE * 3 + 0)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > # ifdef USE_AS_STPCPY
> > > - lea 2(%rdi), %rax
> > > -# endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub $3, %r8
> > > - lea 3(%rdi), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > + leaq (VEC_SIZE * 3 + 0)(%rdi, %rdx, CHAR_SIZE), %rax
> > > # endif
> > > +L(return_end):
> > > ret
> > >
> > > - .p2align 4
> > > -L(Exit3):
> > > - mov (%rsi), %edx
> > > - mov %edx, (%rdi)
> > > + .p2align 4,, 6
> > > +L(ret_vec_x0_end):
> > > + bsf %VRCX, %VRCX
> > > # ifdef USE_AS_STPCPY
> > > - lea 3(%rdi), %rax
> > > -# endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub $4, %r8
> > > - lea 4(%rdi), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rax
> > > # endif
> > > + inc %VRCX
> > > + VMOVU (-(VEC_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), (-(VEC_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > ret
> > >
> > > - .p2align 4
> > > -L(Exit4_7):
> > > - mov (%rsi), %ecx
> > > - mov %ecx, (%rdi)
> > > - mov -3(%rsi, %rdx), %ecx
> > > - mov %ecx, -3(%rdi, %rdx)
> > > + .p2align 4,, 8
> > > +L(ret_vec_x1):
> > > + bsf %VRCX, %VRCX
> > > + VMOVU (VEC_SIZE -(VEC_SIZE - CHAR_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), (VEC_SIZE -(VEC_SIZE - CHAR_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > # ifdef USE_AS_STPCPY
> > > - lea (%rdi, %rdx), %rax
> > > -# endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub %rdx, %r8
> > > - sub $1, %r8
> > > - lea 1(%rdi, %rdx), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > + leaq VEC_SIZE(%rdi, %rcx, CHAR_SIZE), %rax
> > > # endif
> > > ret
> > >
> > > - .p2align 4
> > > -L(Exit8_15):
> > > - mov (%rsi), %rcx
> > > - mov -7(%rsi, %rdx), %r9
> > > - mov %rcx, (%rdi)
> > > - mov %r9, -7(%rdi, %rdx)
> > > + .p2align 4,, 4
> > > +L(ret_vec_x2):
> > > + bsf %VRCX, %VRCX
> > > + VMOVU ((VEC_SIZE * 2)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE * 2)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > # ifdef USE_AS_STPCPY
> > > - lea (%rdi, %rdx), %rax
> > > -# endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub %rdx, %r8
> > > - sub $1, %r8
> > > - lea 1(%rdi, %rdx), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > + leaq (VEC_SIZE * 2)(%rdi, %rcx, CHAR_SIZE), %rax
> > > # endif
> > > ret
> > >
> > > - .p2align 4
> > > -L(Exit16_31):
> > > - VMOVU (%rsi), %XMM2
> > > - VMOVU -15(%rsi, %rdx), %XMM3
> > > - VMOVU %XMM2, (%rdi)
> > > - VMOVU %XMM3, -15(%rdi, %rdx)
> > > + /* ret_vec_x3 reuses return code after the loop. */
> > > + .p2align 4,, 6
> > > +L(ret_vec_x4):
> > > + bsf %VRCX, %VRCX
> > > + VMOVU ((VEC_SIZE * 4)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE * 4)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > # ifdef USE_AS_STPCPY
> > > - lea (%rdi, %rdx), %rax
> > > -# endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub %rdx, %r8
> > > - sub $1, %r8
> > > - lea 1(%rdi, %rdx), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > + leaq (VEC_SIZE * 4)(%rdi, %rcx, CHAR_SIZE), %rax
> > > # endif
> > > ret
> > >
> > > - .p2align 4
> > > -L(Exit32_63):
> > > - VMOVU (%rsi), %YMM2
> > > - VMOVU -31(%rsi, %rdx), %YMM3
> > > - VMOVU %YMM2, (%rdi)
> > > - VMOVU %YMM3, -31(%rdi, %rdx)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %rdx), %rax
> > > +
> > > + .p2align 4,, 4
> > > +L(page_cross):
> > > +# ifndef USE_AS_STRCAT
> > > + vpxorq %VZERO_128, %VZERO_128, %VZERO_128
> > > # endif
> > > -# if defined USE_AS_STRNCPY && !defined USE_AS_STRCAT
> > > - sub %rdx, %r8
> > > - sub $1, %r8
> > > - lea 1(%rdi, %rdx), %rdi
> > > - jnz L(StrncpyFillTailWithZero)
> > > + movq %rsi, %rcx
> > > + andq $(VEC_SIZE * -1), %rcx
> > > +
> > > + VPCMPEQ (%rcx), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > +# ifdef USE_AS_WCSCPY
> > > + andl $(VEC_SIZE - 1), %PAGE_ALIGN_REG
> > > + shrl $2, %PAGE_ALIGN_REG
> > > # endif
> > > - ret
> > > + shrx %VGPR(PAGE_ALIGN_REG_64), %VRCX, %VRCX
> > >
> > > -# ifdef USE_AS_STRNCPY
> > > +# if USE_MOVSB_IN_PAGE_CROSS
> > > + /* Optimizing more aggressively for space as this is very cold
> > > + code. This saves 2x cache lines. */
> > >
> > > - .p2align 4
> > > -L(StrncpyExit1):
> > > - movzbl (%rsi), %edx
> > > - mov %dl, (%rdi)
> > > -# ifdef USE_AS_STPCPY
> > > - lea 1(%rdi), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, 1(%rdi)
> > > + /* This adds once to the later result which will get correct
> > > + copy bounds. NB: this can never zero-out a non-zero RCX as
> > > + to be in the page cross case rsi cannot be aligned and we
> > > + already right-shift rcx by the misalignment. */
> > > + shl %VRCX
> > > + jz L(page_cross_continue)
> > > +# if !defined USE_AS_STPCPY && !defined USE_AS_STRCAT
> > > + movq %rdi, %rax
> > > # endif
> > > - ret
> > > + bsf %VRCX, %VRCX
> > > + REP_MOVS
> > >
> > > - .p2align 4
> > > -L(StrncpyExit2):
> > > - movzwl (%rsi), %edx
> > > - mov %dx, (%rdi)
> > > # ifdef USE_AS_STPCPY
> > > - lea 2(%rdi), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, 2(%rdi)
> > > + leaq -CHAR_SIZE(%rdi), %rax
> > > # endif
> > > ret
> > >
> > > - .p2align 4
> > > -L(StrncpyExit3_4):
> > > - movzwl (%rsi), %ecx
> > > - movzwl -2(%rsi, %r8), %edx
> > > - mov %cx, (%rdi)
> > > - mov %dx, -2(%rdi, %r8)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %r8), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (%rdi, %r8)
> > > -# endif
> > > - ret
> > >
> > > - .p2align 4
> > > -L(StrncpyExit5_8):
> > > - mov (%rsi), %ecx
> > > - mov -4(%rsi, %r8), %edx
> > > - mov %ecx, (%rdi)
> > > - mov %edx, -4(%rdi, %r8)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %r8), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (%rdi, %r8)
> > > -# endif
> > > - ret
> > > +# else
> > > + /* Check if we found zero-char before end of page. */
> > > + test %VRCX, %VRCX
> > > + jz L(page_cross_continue)
> > >
> > > - .p2align 4
> > > -L(StrncpyExit9_16):
> > > - mov (%rsi), %rcx
> > > - mov -8(%rsi, %r8), %rdx
> > > - mov %rcx, (%rdi)
> > > - mov %rdx, -8(%rdi, %r8)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %r8), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (%rdi, %r8)
> > > -# endif
> > > - ret
> > > + /* Traditional copy case, essentially same as used in non-page-
> > > + cross case but since we can't reuse VMM(0) we need twice as
> > > + many loads from rsi. */
> > >
> > > - .p2align 4
> > > -L(StrncpyExit17_32):
> > > - VMOVU (%rsi), %XMM2
> > > - VMOVU -16(%rsi, %r8), %XMM3
> > > - VMOVU %XMM2, (%rdi)
> > > - VMOVU %XMM3, -16(%rdi, %r8)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %r8), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (%rdi, %r8)
> > > +# ifndef USE_AS_STRCAT
> > > + xorl %edx, %edx
> > > # endif
> > > - ret
> > > -
> > > - .p2align 4
> > > -L(StrncpyExit33_64):
> > > - /* 0/32, 31/16 */
> > > - VMOVU (%rsi), %YMM2
> > > - VMOVU -VEC_SIZE(%rsi, %r8), %YMM3
> > > - VMOVU %YMM2, (%rdi)
> > > - VMOVU %YMM3, -VEC_SIZE(%rdi, %r8)
> > > + /* Dependency on rdi must already have been satisfied. */
> > > + bsf %VRCX, %VRDX
> > > # ifdef USE_AS_STPCPY
> > > - lea (%rdi, %r8), %rax
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# elif !defined USE_AS_STRCAT
> > > + movq %rdi, %rax
> > > # endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (%rdi, %r8)
> > > -# endif
> > > - ret
> > >
> > > - .p2align 4
> > > -L(StrncpyExit65):
> > > - /* 0/32, 32/32, 64/1 */
> > > - VMOVU (%rsi), %YMM2
> > > - VMOVU 32(%rsi), %YMM3
> > > - mov 64(%rsi), %cl
> > > - VMOVU %YMM2, (%rdi)
> > > - VMOVU %YMM3, 32(%rdi)
> > > - mov %cl, 64(%rdi)
> > > -# ifdef USE_AS_STPCPY
> > > - lea 65(%rdi), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, 65(%rdi)
> > > +# if VEC_SIZE == 64
> > > +# ifdef USE_AS_WCSCPY
> > > + testb %cl, %cl
> > > +# else
> > > + test %ecx, %ecx
> > > +# endif
> > > + jz L(page_cross_copy_32_63)
> > > # endif
> > > - ret
> > > -
> > > -# ifndef USE_AS_STRCAT
> > >
> > > - .p2align 4
> > > -L(Fill1):
> > > - mov %dl, (%rdi)
> > > - ret
> > > +# ifdef USE_AS_WCSCPY
> > > + testb $0xf, %cl
> > > +# else
> > > + testw %cx, %cx
> > > +# endif
> > > + jz L(page_cross_copy_16_31)
> > >
> > > - .p2align 4
> > > -L(Fill2):
> > > - mov %dx, (%rdi)
> > > - ret
> > > +# ifdef USE_AS_WCSCPY
> > > + testb $0x3, %cl
> > > +# else
> > > + testb %cl, %cl
> > > +# endif
> > > + jz L(page_cross_copy_8_15)
> > >
> > > - .p2align 4
> > > -L(Fill3_4):
> > > - mov %dx, (%rdi)
> > > - mov %dx, -2(%rdi, %r8)
> > > +# ifdef USE_AS_WCSCPY
> > > + movl (%rsi), %esi
> > > + movl %esi, (%rdi)
> > > + movl $0, (%END_REG)
> > > ret
> > > +# else
> > >
> > > - .p2align 4
> > > -L(Fill5_8):
> > > - mov %edx, (%rdi)
> > > - mov %edx, -4(%rdi, %r8)
> > > - ret
> > > + testb $0x7, %cl
> > > + jz L(page_cross_copy_4_7)
> > >
> > > - .p2align 4
> > > -L(Fill9_16):
> > > - mov %rdx, (%rdi)
> > > - mov %rdx, -8(%rdi, %r8)
> > > + test %edx, %edx
> > > + jz L(page_cross_set_null_term)
> > > + movzwl (%rsi), %ecx
> > > + movw %cx, (%rdi)
> > > +L(page_cross_set_null_term):
> > > + movb $0, (%END_REG)
> > > ret
> > >
> > > - .p2align 4
> > > -L(Fill17_32):
> > > - VMOVU %XMMZERO, (%rdi)
> > > - VMOVU %XMMZERO, -16(%rdi, %r8)
> > > - ret
> > >
> > > - .p2align 4
> > > -L(CopyVecSizeUnalignedVec2):
> > > - VMOVU %YMM2, (%rdi, %rcx)
> > > -
> > > - .p2align 4
> > > -L(CopyVecSizeVecExit):
> > > - bsf %edx, %edx
> > > - add $(VEC_SIZE - 1), %r8
> > > - add %rcx, %rdi
> > > -# ifdef USE_AS_STPCPY
> > > - lea (%rdi, %rdx), %rax
> > > -# endif
> > > - sub %rdx, %r8
> > > - lea 1(%rdi, %rdx), %rdi
> > > -
> > > - .p2align 4
> > > -L(StrncpyFillTailWithZero):
> > > - xor %edx, %edx
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(StrncpyFillExit)
> > > -
> > > - VMOVU %YMMZERO, (%rdi)
> > > - add $VEC_SIZE, %rdi
> > > -
> > > - mov %rdi, %rsi
> > > - and $(VEC_SIZE - 1), %esi
> > > - sub %rsi, %rdi
> > > - add %rsi, %r8
> > > - sub $(VEC_SIZE * 4), %r8
> > > - jb L(StrncpyFillLessFourVecSize)
> > > -
> > > -L(StrncpyFillLoopVmovdqa):
> > > - VMOVA %YMMZERO, (%rdi)
> > > - VMOVA %YMMZERO, VEC_SIZE(%rdi)
> > > - VMOVA %YMMZERO, (VEC_SIZE * 2)(%rdi)
> > > - VMOVA %YMMZERO, (VEC_SIZE * 3)(%rdi)
> > > - add $(VEC_SIZE * 4), %rdi
> > > - sub $(VEC_SIZE * 4), %r8
> > > - jae L(StrncpyFillLoopVmovdqa)
> > > -
> > > -L(StrncpyFillLessFourVecSize):
> > > - add $(VEC_SIZE * 2), %r8
> > > - jl L(StrncpyFillLessTwoVecSize)
> > > - VMOVA %YMMZERO, (%rdi)
> > > - VMOVA %YMMZERO, VEC_SIZE(%rdi)
> > > - add $(VEC_SIZE * 2), %rdi
> > > - sub $VEC_SIZE, %r8
> > > - jl L(StrncpyFillExit)
> > > - VMOVA %YMMZERO, (%rdi)
> > > - add $VEC_SIZE, %rdi
> > > - jmp L(Fill)
> > > -
> > > - .p2align 4
> > > -L(StrncpyFillLessTwoVecSize):
> > > - add $VEC_SIZE, %r8
> > > - jl L(StrncpyFillExit)
> > > - VMOVA %YMMZERO, (%rdi)
> > > - add $VEC_SIZE, %rdi
> > > - jmp L(Fill)
> > > -
> > > - .p2align 4
> > > -L(StrncpyFillExit):
> > > - add $VEC_SIZE, %r8
> > > -L(Fill):
> > > - cmp $17, %r8d
> > > - jae L(Fill17_32)
> > > - cmp $9, %r8d
> > > - jae L(Fill9_16)
> > > - cmp $5, %r8d
> > > - jae L(Fill5_8)
> > > - cmp $3, %r8d
> > > - jae L(Fill3_4)
> > > - cmp $1, %r8d
> > > - ja L(Fill2)
> > > - je L(Fill1)
> > > + .p2align 4,, 4
> > > +L(page_cross_copy_4_7):
> > > + movl (%rsi), %ecx
> > > + movl -(4 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %esi
> > > + movl %ecx, (%rdi)
> > > + movl %esi, -(4 - CHAR_SIZE)(%END_REG)
> > > ret
> > > -
> > > -/* end of ifndef USE_AS_STRCAT */
> > > # endif
> > >
> > > - .p2align 4
> > > -L(UnalignedLeaveCase2OrCase3):
> > > - test %rdx, %rdx
> > > - jnz L(UnalignedFourVecSizeLeaveCase2)
> > > -L(UnalignedFourVecSizeLeaveCase3):
> > > - lea (VEC_SIZE * 4)(%r8), %rcx
> > > - and $-VEC_SIZE, %rcx
> > > - add $(VEC_SIZE * 3), %r8
> > > - jl L(CopyVecSizeCase3)
> > > - VMOVU %YMM4, (%rdi)
> > > - sub $VEC_SIZE, %r8
> > > - jb L(CopyVecSizeCase3)
> > > - VMOVU %YMM5, VEC_SIZE(%rdi)
> > > - sub $VEC_SIZE, %r8
> > > - jb L(CopyVecSizeCase3)
> > > - VMOVU %YMM6, (VEC_SIZE * 2)(%rdi)
> > > - sub $VEC_SIZE, %r8
> > > - jb L(CopyVecSizeCase3)
> > > - VMOVU %YMM7, (VEC_SIZE * 3)(%rdi)
> > > -# ifdef USE_AS_STPCPY
> > > - lea (VEC_SIZE * 4)(%rdi), %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (VEC_SIZE * 4)(%rdi)
> > > -# endif
> > > +# if VEC_SIZE == 64
> > > + .p2align 4,, 4
> > > +L(page_cross_copy_32_63):
> > > + VMOVU (%rsi), %VMM_256(0)
> > > + VMOVU -(32 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %VMM_256(1)
> > > + VMOVU %VMM_256(0), (%rdi)
> > > + VMOVU %VMM_256(1), -(32 - CHAR_SIZE)(%END_REG)
> > > ret
> > > -
> > > - .p2align 4
> > > -L(UnalignedFourVecSizeLeaveCase2):
> > > - xor %ecx, %ecx
> > > - vpcmpb $0, %YMM4, %YMMZERO, %k1
> > > - kmovd %k1, %edx
> > > - add $(VEC_SIZE * 3), %r8
> > > - jle L(CopyVecSizeCase2OrCase3)
> > > - test %edx, %edx
> > > -# ifndef USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec4)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > -# endif
> > > - vpcmpb $0, %YMM5, %YMMZERO, %k2
> > > - kmovd %k2, %edx
> > > - VMOVU %YMM4, (%rdi)
> > > - add $VEC_SIZE, %rcx
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > - test %edx, %edx
> > > -# ifndef USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec5)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > # endif
> > >
> > > - vpcmpb $0, %YMM6, %YMMZERO, %k3
> > > - kmovd %k3, %edx
> > > - VMOVU %YMM5, VEC_SIZE(%rdi)
> > > - add $VEC_SIZE, %rcx
> > > - sub $VEC_SIZE, %r8
> > > - jbe L(CopyVecSizeCase2OrCase3)
> > > - test %edx, %edx
> > > -# ifndef USE_AS_STRCAT
> > > - jnz L(CopyVecSizeUnalignedVec6)
> > > -# else
> > > - jnz L(CopyVecSize)
> > > -# endif
> > > -
> > > - vpcmpb $0, %YMM7, %YMMZERO, %k4
> > > - kmovd %k4, %edx
> > > - VMOVU %YMM6, (VEC_SIZE * 2)(%rdi)
> > > - lea VEC_SIZE(%rdi, %rcx), %rdi
> > > - lea VEC_SIZE(%rsi, %rcx), %rsi
> > > - bsf %edx, %edx
> > > - cmp %r8d, %edx
> > > - jb L(CopyVecSizeExit)
> > > -L(StrncpyExit):
> > > - cmp $65, %r8d
> > > - je L(StrncpyExit65)
> > > - cmp $33, %r8d
> > > - jae L(StrncpyExit33_64)
> > > - cmp $17, %r8d
> > > - jae L(StrncpyExit17_32)
> > > - cmp $9, %r8d
> > > - jae L(StrncpyExit9_16)
> > > - cmp $5, %r8d
> > > - jae L(StrncpyExit5_8)
> > > - cmp $3, %r8d
> > > - jae L(StrncpyExit3_4)
> > > - cmp $1, %r8d
> > > - ja L(StrncpyExit2)
> > > - je L(StrncpyExit1)
> > > -# ifdef USE_AS_STPCPY
> > > - mov %rdi, %rax
> > > -# endif
> > > -# ifdef USE_AS_STRCAT
> > > - movb $0, (%rdi)
> > > -# endif
> > > + .p2align 4,, 4
> > > +L(page_cross_copy_16_31):
> > > + vmovdqu (%rsi), %xmm0
> > > + vmovdqu -(16 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %xmm1
> > > + vmovdqu %xmm0, (%rdi)
> > > + vmovdqu %xmm1, -(16 - CHAR_SIZE)(%END_REG)
> > > ret
> > >
> > > - .p2align 4
> > > -L(ExitZero):
> > > -# ifndef USE_AS_STRCAT
> > > - mov %rdi, %rax
> > > -# endif
> > > + .p2align 4,, 4
> > > +L(page_cross_copy_8_15):
> > > + movq (%rsi), %rcx
> > > + movq -(8 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %rsi
> > > + movq %rcx, (%rdi)
> > > + movq %rsi, -(8 - CHAR_SIZE)(%END_REG)
> > > ret
> > > -
> > > -# endif
> > > -
> > > -# ifndef USE_AS_STRCAT
> > > -END (STRCPY)
> > > -# else
> > > -END (STRCAT)
> > > # endif
> > > +END(STRCPY)
> > > #endif
> > > diff --git a/sysdeps/x86_64/multiarch/strncat-evex.S b/sysdeps/x86_64/multiarch/strncat-evex.S
> > > index 203a19bf21..d648ba5cfe 100644
> > > --- a/sysdeps/x86_64/multiarch/strncat-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/strncat-evex.S
> > > @@ -1,7 +1,520 @@
> > > -#ifndef STRNCAT
> > > -# define STRNCAT __strncat_evex
> > > -#endif
> > > +/* {wcs|str}ncat with 256/512-bit EVEX.
> > > + Copyright (C) 2022 Free Software Foundation, Inc.
> > > + This file is part of the GNU C Library.
> > > +
> > > + The GNU C Library is free software; you can redistribute it and/or
> > > + modify it under the terms of the GNU Lesser General Public
> > > + License as published by the Free Software Foundation; either
> > > + version 2.1 of the License, or (at your option) any later version.
> > > +
> > > + The GNU C Library is distributed in the hope that it will be useful,
> > > + but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > > + Lesser General Public License for more details.
> > > +
> > > + You should have received a copy of the GNU Lesser General Public
> > > + License along with the GNU C Library; if not, see
> > > + <https://www.gnu.org/licenses/>. */
> > > +
> > > +#include <isa-level.h>
> > > +
> > > +#if ISA_SHOULD_BUILD (4)
> > > +
> > > + /* Use evex-masked stores for small sizes. Turned off at the
> > > + moment. */
> > > +# define USE_EVEX_MASKED_STORE 0
> > > +
> > > +# include <sysdep.h>
> > > +
> > > +# ifndef VEC_SIZE
> > > +# include "x86-evex256-vecs.h"
> > > +# endif
> > > +
> > > +# ifndef STRNCAT
> > > +# define STRNCAT __strncat_evex
> > > +# endif
> > > +
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > +# define movNULL movl
> > > +# define VMOVU_MASK vmovdqu32
> > > +# define VPMIN vpminud
> > > +# define VPTESTN vptestnmd
> > > +# define VPTEST vptestmd
> > > +# define VPCMPEQ vpcmpeqd
> > > +# define CHAR_SIZE 4
> > > +
> > > +# define REP_MOVS rep movsd
> > > +
> > > +# define VMASK_REG VR10
> > > +# define FIND_FIRST_ONE(src, dst) movl $CHAR_PER_VEC, %dst; bsf %src, %dst
> > > +
> > > +# define USE_WIDE_CHAR
> > > +# else
> > > +# define movNULL movb
> > > +# define VMOVU_MASK vmovdqu8
> > > +# define VPMIN vpminub
> > > +# define VPTESTN vptestnmb
> > > +# define VPTEST vptestmb
> > > +# define VPCMPEQ vpcmpeqb
> > > +# define CHAR_SIZE 1
> > > +
> > > +# define REP_MOVS rep movsb
> > > +
> > > +# define VMASK_REG VRCX
> > > +# define FIND_FIRST_ONE(src, dst) tzcnt %src, %dst
> > > +
> > > +# endif
> > > +
> > > +# include "strncpy-or-cat-overflow-def.h"
> > > +
> > > +# include "reg-macros.h"
> > > +
> > > +
> > > +# define VZERO VMM(7)
> > > +# define VZERO_128 VMM_128(7)
> > > +
> > > +# define PAGE_SIZE 4096
> > > +# define CHAR_PER_VEC (VEC_SIZE / CHAR_SIZE)
> > > +
> > > + .section SECTION(.text), "ax", @progbits
> > > +ENTRY(STRNCAT)
> > > + movq %rdi, %rax
> > > +
> > > + /* NB: It's safe to filter out zero-length strings WITHOUT
> > > + setting null-term. Destination MUST be a null-terminated
> > > + string so essentially the work is already done. */
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq -1(%rdx), %rcx
> > > + shrq $56, %rcx
> > > + jnz L(zero_len)
> > > +# else
> > > + test %rdx, %rdx
> > > + jle L(zero_len)
> > > +# endif
> > > +
> > > +# include "strcat-strlen-evex.S"
> > > +
> > > + movl %esi, %ecx
> > > + andl $(PAGE_SIZE - 1), %ecx
> > > + cmpl $(PAGE_SIZE - VEC_SIZE), %ecx
> > > + ja L(page_cross)
> > > +L(page_cross_continue):
> > > + VMOVU (%rsi), %VMM(0)
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > +
> > > + /* If USE_EVEX_MASK_STORE is enabled then we just handle length
> > > + <= CHAR_PER_VEC with masked instructions (which have
> > > + potential for dramatically bad perf if dst splits a page and
> > > + is not in the TLB). */
> > > +# if USE_EVEX_MASKED_STORE
> > > + KMOV %k0, %VRCX
> > > + FIND_FIRST_ONE (VRCX, VR8)
> > > + cmpq %r8, %rdx
> > > + jbe L(less_1x_vec)
> > > +
> > > + test %VRCX, %VRCX
> > > + jz L(more_1x_vec)
> > > +
> > > + blsmsk %VRCX, %VRCX
> > > + KMOV %VRCX, %k1
> > > + VMOVU_MASK %VMM(0), (%rdi){%k1}
> > > + ret
> > > +
> > > +L(less_1x_vec):
> > > + mov $-1, %VRCX
> > > + bzhi %VRDX, %VRCX, %VRCX
> > > + KMOV %VRCX, %k1
> > > + movNULL $0, (%rdi, %rdx, CHAR_SIZE)
> > > + VMOVU_MASK %VMM(0), (%rdi){%k1}
> > > +
> > > + ret
> > > +# else
> > > + KMOV %k0, %VMASK_REG
> > > + /* tzcnt for strncat and `movl $CHAR_PER_VEC, %VRCX; bsf
> > > + %VMASK_REG, %VRCX` for wcsncat. */
> > > + FIND_FIRST_ONE (VMASK_REG, VRCX)
> > > + cmpq %rcx, %rdx
> > > + jbe L(less_1x_vec)
> > > +
> > > + /* If there were no zero-CHARs (rcx was zero before
> > > + FIND_FIRST_ONE), then ecx will be $CHAR_PER_VEC. */
> > > + cmpl $CHAR_PER_VEC, %ecx
> > > + je L(more_1x_vec)
> > > +
> > > + movl %ecx, %edx
> > > +
> > > +L(less_1x_vec):
> > > +# if VEC_SIZE == 64
> > > + cmpl $(32 / CHAR_SIZE), %edx
> > > + jae L(copy_32_63)
> > > +# endif
> > > +
> > > + cmpl $(16 / CHAR_SIZE), %edx
> > > + jae L(copy_16_31)
> > > +
> > > +
> > > + cmpl $(8 / CHAR_SIZE), %edx
> > > + jae L(copy_8_15)
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > + vmovd %VMM_128(0), (%rdi)
> > > + movNULL $0, (%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +# else
> > > +
> > > + cmpl $4, %edx
> > > + jae L(copy_4_7)
> > > +
> > > + movzbl (%rsi), %ecx
> > > + cmpl $1, %edx
> > > + jbe L(set_null_term)
> > > +
> > > + movzwl 1(%rsi), %esi
> > > + movw %si, 1(%rdi)
> > > +
> > > + .p2align 4,, 1
> > > +L(set_null_term):
> > > + movb %cl, (%rdi)
> > > + movNULL $0, (%rdi, %rdx)
> > > + ret
> > > +# endif
> > > +
> > > +# if VEC_SIZE == 64
> > > + .p2align 4,, 6
> > > +L(copy_32_63):
> > > + VMOVU -(32)(%rsi, %rdx, CHAR_SIZE), %VMM_256(1)
> > > + VMOVU %VMM_256(0), (%rdi)
> > > + VMOVU %VMM_256(1), -(32)(%rdi, %rdx, CHAR_SIZE)
> > > + movNULL $0, (%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +# endif
> > > + .p2align 4,, 6
> > > +L(copy_16_31):
> > > + /* Use xmm1 explicitly here as it won't require a `vzeroupper`
> > > + and will save code size. */
> > > + vmovdqu -(16)(%rsi, %rdx, CHAR_SIZE), %xmm1
> > > + VMOVU %VMM_128(0), (%rdi)
> > > + vmovdqu %xmm1, -(16)(%rdi, %rdx, CHAR_SIZE)
> > > + movNULL $0, (%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +
> > > + .p2align 4,, 2
> > > +L(copy_8_15):
> > > + movq -(8)(%rsi, %rdx, CHAR_SIZE), %rcx
> > > + vmovq %VMM_128(0), (%rdi)
> > > + movq %rcx, -(8)(%rdi, %rdx, CHAR_SIZE)
> > > + movNULL $0, (%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +
> > > +# ifndef USE_AS_WCSCPY
> > > + .p2align 4,, 12
> > > +L(copy_4_7):
> > > + movl -(4)(%rsi, %rdx, CHAR_SIZE), %ecx
> > > + vmovd %VMM_128(0), (%rdi)
> > > + movl %ecx, -(4)(%rdi, %rdx, CHAR_SIZE)
> > > + movNULL $0, (%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +# endif
> > > +
> > > +# endif
> > > + .p2align 4,, 4
> > > +L(zero_len):
> > > +# ifdef USE_AS_WCSCPY
> > > + test %rdx, %rdx
> > > +# endif
> > > + jne OVERFLOW_STRCAT
> > > + ret
> > >
> > > -#define USE_AS_STRNCAT
> > > -#define STRCAT STRNCAT
> > > -#include "strcat-evex.S"
> > > + .p2align 4,, 8
> > > +L(more_1x_vec):
> > > + VMOVU %VMM(0), (%rdi)
> > > +
> > > + /* We are going to align rsi here so will need to be able to re-
> > > + adjust rdi/rdx afterwords. NB: We filtered out huge lengths
> > > + so rsi + rdx * CHAR_SIZE cannot overflow. */
> > > +
> > > + leaq (VEC_SIZE * -1)(%rsi, %rdx, CHAR_SIZE), %rdx
> > > + subq %rsi, %rdi
> > > + andq $-(VEC_SIZE), %rsi
> > > +L(loop_last_4x_vec):
> > > + addq %rsi, %rdi
> > > + subq %rsi, %rdx
> > > +# ifdef USE_AS_WCSCPY
> > > + shrq $2, %rdx
> > > +# endif
> > > +
> > > + /* Will need this regardless. */
> > > + VMOVA (VEC_SIZE * 1)(%rsi), %VMM(1)
> > > + VPTESTN %VMM(1), %VMM(1), %k0
> > > + KMOV %k0, %VMASK_REG
> > > +
> > > + cmpq $(CHAR_PER_VEC * 2), %rdx
> > > + ja L(more_2x_vec)
> > > +
> > > +L(last_2x_vec):
> > > + FIND_FIRST_ONE (VMASK_REG, VRCX)
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_vec_x1_len)
> > > +
> > > + /* If there were no zero-CHARs (rcx was zero before
> > > + FIND_FIRST_ONE), then ecx will be $CHAR_PER_VEC. */
> > > + cmpl $CHAR_PER_VEC, %ecx
> > > + jne L(ret_vec_x1)
> > > +
> > > + VMOVA (VEC_SIZE * 2)(%rsi), %VMM(2)
> > > + VMOVU %VMM(1), (VEC_SIZE * 1)(%rdi)
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + addl $-CHAR_PER_VEC, %edx
> > > + bzhi %VRDX, %VRCX, %VR8
> > > + jz L(ret_vec_x2_len)
> > > +L(ret_vec_x2):
> > > + bsf %VRCX, %VRDX
> > > +L(ret_vec_x2_len):
> > > + VMOVU (VEC_SIZE * 2 -(VEC_SIZE))(%rsi, %rdx, CHAR_SIZE), %VMM(0)
> > > + movNULL $0, (VEC_SIZE * 2)(%rdi, %rdx, CHAR_SIZE)
> > > + VMOVU %VMM(0), (VEC_SIZE * 2 -(VEC_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +
> > > + .p2align 4,, 4
> > > +L(ret_vec_x1_len):
> > > + movl %edx, %ecx
> > > +L(ret_vec_x1):
> > > + VMOVU (VEC_SIZE -(VEC_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + movNULL $0, (VEC_SIZE)(%rdi, %rcx, CHAR_SIZE)
> > > + VMOVU %VMM(0), (VEC_SIZE-(VEC_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > + VZEROUPPER_RETURN
> > > +
> > > +
> > > + .p2align 4,, 8
> > > +L(last_4x_vec):
> > > + addl $-(CHAR_PER_VEC * 4), %edx
> > > + VMOVA (VEC_SIZE * 5)(%rsi), %VMM(1)
> > > + VPTESTN %VMM(1), %VMM(1), %k0
> > > + KMOV %k0, %VMASK_REG
> > > + subq $-(VEC_SIZE * 4), %rsi
> > > + subq $-(VEC_SIZE * 4), %rdi
> > > + cmpl $(CHAR_PER_VEC * 2), %edx
> > > + jbe L(last_2x_vec)
> > > + .p2align 4,, 8
> > > +L(more_2x_vec):
> > > +# ifdef USE_AS_WCSCPY
> > > + xorl %ecx, %ecx
> > > +# endif
> > > + bsf %VMASK_REG, %VRCX
> > > + jnz L(ret_vec_x1)
> > > +
> > > + VMOVA (VEC_SIZE * 2)(%rsi), %VMM(2)
> > > + VMOVU %VMM(1), (VEC_SIZE * 1)(%rdi)
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x2)
> > > +
> > > + VMOVA (VEC_SIZE * 3)(%rsi), %VMM(3)
> > > + VMOVU %VMM(2), (VEC_SIZE * 2)(%rdi)
> > > + VPTESTN %VMM(3), %VMM(3), %k0
> > > + KMOV %k0, %VMASK_REG
> > > +
> > > + cmpq $(CHAR_PER_VEC * 4), %rdx
> > > + ja L(more_4x_vec)
> > > +
> > > + /* Adjust length before going to L(ret_vec_x3_len) or
> > > + L(ret_vec_x3). */
> > > + addl $(CHAR_PER_VEC * -2), %edx
> > > +
> > > + FIND_FIRST_ONE (VMASK_REG, VRCX)
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_vec_x3_len)
> > > +
> > > + /* If there were no zero-CHARs (rcx was zero before
> > > + FIND_FIRST_ONE), then ecx will be $CHAR_PER_VEC. */
> > > + cmpl $CHAR_PER_VEC, %ecx
> > > + jne L(ret_vec_x3)
> > > +
> > > + VMOVA (VEC_SIZE * 4)(%rsi), %VMM(4)
> > > + VMOVU %VMM(3), (VEC_SIZE * 3)(%rdi)
> > > + VPTESTN %VMM(4), %VMM(4), %k0
> > > + KMOV %k0, %VRCX
> > > + addl $-CHAR_PER_VEC, %edx
> > > + bzhi %VRDX, %VRCX, %VR8
> > > + jz L(ret_vec_x4_len)
> > > +L(ret_vec_x4):
> > > + bsf %VRCX, %VRDX
> > > +L(ret_vec_x4_len):
> > > + VMOVU (VEC_SIZE * 4 -(VEC_SIZE))(%rsi, %rdx, CHAR_SIZE), %VMM(0)
> > > + movNULL $0, (VEC_SIZE * 4)(%rdi, %rdx, CHAR_SIZE)
> > > + VMOVU %VMM(0), (VEC_SIZE * 4 -(VEC_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +
> > > + .p2align 4,, 4
> > > +L(ret_vec_x3_len):
> > > + movl %edx, %ecx
> > > +L(ret_vec_x3):
> > > + VMOVU (VEC_SIZE * 3 -(VEC_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + movNULL $0, (VEC_SIZE * 3)(%rdi, %rcx, CHAR_SIZE)
> > > + VMOVU %VMM(0), (VEC_SIZE * 3-(VEC_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(more_4x_vec):
> > > +# ifdef USE_AS_WCSCPY
> > > + xorl %ecx, %ecx
> > > +# endif
> > > + bsf %VMASK_REG, %VRCX
> > > + jnz L(ret_vec_x3)
> > > +
> > > + VMOVA (VEC_SIZE * 4)(%rsi), %VMM(4)
> > > + VMOVU %VMM(3), (VEC_SIZE * 3)(%rdi)
> > > + VPTESTN %VMM(4), %VMM(4), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x4)
> > > +
> > > + VMOVU %VMM(4), (VEC_SIZE * 4)(%rdi)
> > > +
> > > + /* Check if we are near the end before aligning. */
> > > + cmpq $(CHAR_PER_VEC * 8), %rdx
> > > + jbe L(last_4x_vec)
> > > +
> > > +
> > > + /* Add rsi to rdx (length) before aligning rsi. NB: Since we
> > > + filtered out huge lengths this cannot overflow. */
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rsi, %rdx, CHAR_SIZE), %rdx
> > > +# else
> > > + addq %rsi, %rdx
> > > +# endif
> > > +
> > > + /* Subtract rsi from rdi before aligning (add back will have
> > > + correct rdi for aligned rsi). */
> > > + subq %rsi, %rdi
> > > + subq $-(VEC_SIZE * 5), %rsi
> > > + andq $(VEC_SIZE * -4), %rsi
> > > +
> > > + /* Load first half of the loop before entry. */
> > > + VMOVA (VEC_SIZE * 0 + 0)(%rsi), %VMM(0)
> > > + VMOVA (VEC_SIZE * 1 + 0)(%rsi), %VMM(1)
> > > + VMOVA (VEC_SIZE * 2 + 0)(%rsi), %VMM(2)
> > > + VMOVA (VEC_SIZE * 3 + 0)(%rsi), %VMM(3)
> > > +
> > > + VPMIN %VMM(0), %VMM(1), %VMM(4)
> > > + VPMIN %VMM(2), %VMM(3), %VMM(6)
> > > + VPTESTN %VMM(4), %VMM(4), %k2
> > > + VPTESTN %VMM(6), %VMM(6), %k4
> > > +
> > > + /* Offset rsi by VEC_SIZE so that we can jump to
> > > + L(loop_last_4x_vec). */
> > > + addq $-(VEC_SIZE), %rsi
> > > + KORTEST %k2, %k4
> > > + jnz L(loop_4x_done)
> > > +
> > > + /* Store loop end in r9. */
> > > + leaq -(VEC_SIZE * 5)(%rdx), %r9
> > > +
> > > + .p2align 4,, 11
> > > +L(loop_4x_vec):
> > > + VMOVU %VMM(0), (VEC_SIZE * 1 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(1), (VEC_SIZE * 2 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(2), (VEC_SIZE * 3 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(3), (VEC_SIZE * 4 + 0)(%rdi, %rsi)
> > > +
> > > + subq $(VEC_SIZE * -4), %rsi
> > > + cmpq %rsi, %r9
> > > + jbe L(loop_last_4x_vec)
> > > +
> > > + VMOVA (VEC_SIZE * 1 + 0)(%rsi), %VMM(0)
> > > + VMOVA (VEC_SIZE * 2 + 0)(%rsi), %VMM(1)
> > > + VMOVA (VEC_SIZE * 3 + 0)(%rsi), %VMM(2)
> > > + VMOVA (VEC_SIZE * 4 + 0)(%rsi), %VMM(3)
> > > +
> > > + VPMIN %VMM(0), %VMM(1), %VMM(4)
> > > + VPMIN %VMM(2), %VMM(3), %VMM(6)
> > > + VPTESTN %VMM(4), %VMM(4), %k2
> > > + VPTESTN %VMM(6), %VMM(6), %k4
> > > + KORTEST %k2, %k4
> > > + jz L(loop_4x_vec)
> > > +
> > > +L(loop_4x_done):
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > + /* Restore rdi (dst). */
> > > + addq %rsi, %rdi
> > > +
> > > + /* L(ret_vec_x1) expects rcx to have position of zero-CHAR so
> > > + test with bsf. */
> > > + bsf %VRCX, %VRCX
> > > + jnz L(ret_vec_x1)
> > > + VMOVU %VMM(0), (VEC_SIZE * 1 + 0)(%rdi)
> > > +
> > > + KMOV %k2, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x2)
> > > + VMOVU %VMM(1), (VEC_SIZE * 2 + 0)(%rdi)
> > > +
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + bsf %VRCX, %VRCX
> > > + jnz L(ret_vec_x3)
> > > + VMOVU %VMM(2), (VEC_SIZE * 3 + 0)(%rdi)
> > > +
> > > + KMOV %k4, %VRCX
> > > + bsf %VRCX, %VRCX
> > > + VMOVU ((VEC_SIZE * 4)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rcx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE * 4 + 0)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rcx, CHAR_SIZE)
> > > + ret
> > > +
> > > +
> > > + .p2align 4,, 4
> > > +L(page_cross):
> > > + movq %rsi, %r8
> > > + andq $(VEC_SIZE * -1), %r8
> > > + VPCMPEQ (%r8), %VZERO, %k0
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > + KMOV %k0, %VR9
> > > + shrl $2, %ecx
> > > + andl $(CHAR_PER_VEC - 1), %ecx
> > > + shrx %VRCX, %VR9, %VRCX
> > > +# else
> > > + KMOV %k0, %VRCX
> > > + shrx %VRSI, %VRCX, %VRCX
> > > +# endif
> > > +
> > > + subl %esi, %r8d
> > > + andl $(VEC_SIZE - 1), %r8d
> > > +# ifdef USE_AS_WCSCPY
> > > + shrl $2, %r8d
> > > +# endif
> > > + cmpq %r8, %rdx
> > > + jbe L(page_cross_small)
> > > + /* Optimizing more for space as this is very cold code. This
> > > + saves 2x cache lines. */
> > > +
> > > + /* This adds once to the later result which will get correct
> > > + copy bounds. NB: this can never zero-out a non-zero RCX as
> > > + to be in the page cross case rsi cannot be aligned and we
> > > + already right-shift rcx by the misalignment. */
> > > + shl %VRCX
> > > + jz L(page_cross_continue)
> > > + bsf %VRCX, %VRCX
> > > + REP_MOVS
> > > + ret
> > > +
> > > +L(page_cross_small):
> > > + tzcnt %VRCX, %VRCX
> > > + jz L(page_cross_setz)
> > > + cmpl %edx, %ecx
> > > + cmova %edx, %ecx
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > + rep movsd
> > > +# else
> > > + rep movsb
> > > +# endif
> > > +L(page_cross_setz):
> > > + movNULL $0, (%rdi)
> > > + ret
> > > +END(STRNCAT)
> > > +#endif
> > > diff --git a/sysdeps/x86_64/multiarch/strncpy-evex.S b/sysdeps/x86_64/multiarch/strncpy-evex.S
> > > index 1b3426d511..49eaf4cbd9 100644
> > > --- a/sysdeps/x86_64/multiarch/strncpy-evex.S
> > > +++ b/sysdeps/x86_64/multiarch/strncpy-evex.S
> > > @@ -1,7 +1,990 @@
> > > -#ifndef STRNCPY
> > > -# define STRNCPY __strncpy_evex
> > > -#endif
> > > +/* {wcs|wcp|str|stp}ncpy with 256/512-bit EVEX instructions.
> > > + Copyright (C) 2022 Free Software Foundation, Inc.
> > > + This file is part of the GNU C Library.
> > > +
> > > + The GNU C Library is free software; you can redistribute it and/or
> > > + modify it under the terms of the GNU Lesser General Public
> > > + License as published by the Free Software Foundation; either
> > > + version 2.1 of the License, or (at your option) any later version.
> > > +
> > > + The GNU C Library is distributed in the hope that it will be useful,
> > > + but WITHOUT ANY WARRANTY; without even the implied warranty of
> > > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> > > + Lesser General Public License for more details.
> > > +
> > > + You should have received a copy of the GNU Lesser General Public
> > > + License along with the GNU C Library; if not, see
> > > + <https://www.gnu.org/licenses/>. */
> > > +
> > > +#include <isa-level.h>
> > > +
> > > +#if ISA_SHOULD_BUILD (4)
> > > +
> > > + /* Use evex-masked stores for small sizes. Turned off at the
> > > + moment. */
> > > +# define USE_EVEX_MASKED_STORE 0
> > > +
> > > +
> > > +# include <sysdep.h>
> > > +# ifndef VEC_SIZE
> > > +# include "x86-evex256-vecs.h"
> > > +# endif
> > > +
> > > +
> > > +# ifndef STRNCPY
> > > +# define STRNCPY __strncpy_evex
> > > +# endif
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > +# define VMOVU_MASK vmovdqu32
> > > +# define VPCMPEQ vpcmpeqd
> > > +# define VPMIN vpminud
> > > +# define VPTESTN vptestnmd
> > > +# define VPTEST vptestmd
> > > +# define CHAR_SIZE 4
> > > +
> > > +# define REP_MOVS rep movsd
> > > +# define REP_STOS rep stosl
> > > +
> > > +# define USE_WIDE_CHAR
> > > +
> > > +# else
> > > +# define VMOVU_MASK vmovdqu8
> > > +# define VPCMPEQ vpcmpeqb
> > > +# define VPMIN vpminub
> > > +# define VPTESTN vptestnmb
> > > +# define VPTEST vptestmb
> > > +# define CHAR_SIZE 1
> > > +
> > > +# define REP_MOVS rep movsb
> > > +# define REP_STOS rep stosb
> > > +# endif
> > > +
> > > +# include "strncpy-or-cat-overflow-def.h"
> > > +
> > > +# define PAGE_SIZE 4096
> > > +# define CHAR_PER_VEC (VEC_SIZE / CHAR_SIZE)
> > > +
> > > +# include "reg-macros.h"
> > > +
> > > +
> > > +# define VZERO VMM(7)
> > > +# define VZERO_256 VMM_256(7)
> > > +# define VZERO_128 VMM_128(7)
> > > +
> > > +# if VEC_SIZE == 64
> > > +# define VZERO_HALF VZERO_256
> > > +# else
> > > +# define VZERO_HALF VZERO_128
> > > +# endif
> > > +
> > > + .section SECTION(.text), "ax", @progbits
> > > +ENTRY(STRNCPY)
> > > + /* Filter zero length strings and very long strings. Zero
> > > + length strings just return, very long strings are handled by
> > > + just running rep stos{b|l} to zero set (which will almost
> > > + certainly segfault), if that succeeds then just calling
> > > + OVERFLOW_STRCPY (strcpy, stpcpy, wcscpy, wcpcpy). */
> > > +# ifdef USE_AS_WCSCPY
> > > + decq %rdx
> > > + movq %rdx, %rax
> > > + /* 56 is end of max supported address space. */
> > > + shr $56, %rax
> > > + jnz L(zero_len)
> > > +# else
> > > + decq %rdx
> > > + /* If the flag needs to become `jb` replace `dec` with `sub`.
> > > + */
> > > + jl L(zero_len)
> > > +# endif
> > > +
> > > + vpxorq %VZERO_128, %VZERO_128, %VZERO_128
> > > + movl %esi, %eax
> > > + andl $(PAGE_SIZE - 1), %eax
> > > + cmpl $(PAGE_SIZE - VEC_SIZE), %eax
> > > + ja L(page_cross)
> > > +
> > > +L(page_cross_continue):
> > > + VMOVU (%rsi), %VMM(0)
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > +
> > > + /* If no STPCPY just save end ahead of time. */
> > > +# ifndef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > +
> > > +
> > > + cmpq $(CHAR_PER_VEC), %rdx
> > > +
> > > + /* If USE_EVEX_MASK_STORE is enabled then we just handle length
> > > + <= CHAR_PER_VEC with masked instructions (which have
> > > + potential for dramatically bad perf if dst splits a page and
> > > + is not in the TLB). */
> > > +# if USE_EVEX_MASKED_STORE
> > > + /* `jae` because length rdx is now length - 1. */
> > > + jae L(more_1x_vec)
> > > +
> > > + /* If there where multiple zero-CHAR matches in the first VEC,
> > > + VRCX will be overset but thats fine since any oversets where
> > > + at zero-positions anyways. */
> > > +
> > > +# ifdef USE_AS_STPCPY
> > > + tzcnt %VRCX, %VRAX
> > > + cmpl %eax, %edx
> > > + cmovb %edx, %eax
> > > +# ifdef USE_AS_WCSCPY
> > > + adcl $0, %eax
> > > + leaq (%rdi, %rax, CHAR_SIZE), %rax
> > > +# else
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + dec %VRCX
> > > +
> > > + /* Zero out all non-zero CHAR's after the first zero match. */
> > > + KMOV %VRCX, %k1
> > > +
> > > + /* Use VZERO as destination so this can be reused for
> > > + L(zfill_less_vec) (which if jumped to by subsequent logic
> > > + will have zerod out VZERO. */
> > > + VMOVU_MASK %VMM(0), %VZERO{%k1}{z}
> > > +L(zfill_less_vec):
> > > + /* Get mask for what we need to set. */
> > > + incl %edx
> > > + mov $-1, %VRCX
> > > + bzhi %VRDX, %VRCX, %VRCX
> > > + KMOV %VRCX, %k1
> > > + VMOVU_MASK %VZERO, (%rdi){%k1}
> > > + ret
> > > +
> > > + .p2align 4,, 4
> > > +L(zero_len):
> > > + cmpq $-1, %rdx
> > > + jne L(best_effort_strncpy)
> > > + movq %rdi, %rax
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(more_1x_vec):
> > > +# else
> > > + /* `jb` because length rdx is now length - 1. */
> > > + jb L(less_1x_vec)
> > > +# endif
> > > +
> > > +
> > > + /* This may overset but thats fine because we still need to zero
> > > + fill. */
> > > + VMOVU %VMM(0), (%rdi)
> > > +
> > > +
> > > + /* Length must be >= CHAR_PER_VEC so match here means we must
> > > + zero-fill. */
> > > + test %VRCX, %VRCX
> > > + jnz L(zfill)
> > > +
> > > +
> > > + /* We are going to align rsi here so will need to be able to re-
> > > + adjust rdi/rdx afterwords. NB: We filtered out huge lengths
> > > + so rsi + rdx * CHAR_SIZE cannot overflow. */
> > > + leaq (VEC_SIZE * -1)(%rsi, %rdx, CHAR_SIZE), %rdx
> > > + subq %rsi, %rdi
> > > + andq $-(VEC_SIZE), %rsi
> > > +
> > > +L(loop_last_4x_vec):
> > > + addq %rsi, %rdi
> > > + subq %rsi, %rdx
> > > +# ifdef USE_AS_WCSCPY
> > > + shrq $2, %rdx
> > > +# endif
> > > +
> > > + VMOVA (VEC_SIZE * 1)(%rsi), %VMM(1)
> > > + VPTESTN %VMM(1), %VMM(1), %k0
> > > + KMOV %k0, %VRCX
> > > +
> > > + /* -1 because of the `dec %rdx` earlier. */
> > > + cmpq $(CHAR_PER_VEC * 2 - 1), %rdx
> > > + ja L(more_2x_vec)
> > > +
> > > +L(last_2x_vec):
> > > + /* This will be need to be computed no matter what. We do it
> > > + ahead of time for CHAR_PER_VEC == 64 because we can't adjust
> > > + the value of `tzcnt` with a shift. */
> > > +# if CHAR_PER_VEC == 64
> > > + tzcntq %rcx, %rcx
> > > +# endif
> > > +
> > > + cmpl $(CHAR_PER_VEC), %edx
> > > + jb L(ret_vec_x1_len)
> > > +
> > > + /* Seperate logic for CHAR_PER_VEC == 64 because we already did
> > > + `tzcnt` on VRCX. */
> > > +# if CHAR_PER_VEC == 64
> > > + /* cl == CHAR_PER_VEC iff it was zero before the `tzcnt`. */
> > > + cmpb $CHAR_PER_VEC, %cl
> > > + jnz L(ret_vec_x1_no_bsf)
> > > +# else
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x1)
> > > +# endif
> > > +
> > > +
> > > +
> > > + VPCMPEQ (VEC_SIZE * 2)(%rsi), %VZERO, %k0
> > > + VMOVU %VMM(1), (VEC_SIZE * 1)(%rdi)
> > > + KMOV %k0, %VRCX
> > > +
> > > +# if CHAR_PER_VEC < 64
> > > + /* This essentiallys adds CHAR_PER_VEC to computed result. */
> > > + shlq $CHAR_PER_VEC, %rcx
> > > +# else
> > > + tzcntq %rcx, %rcx
> > > + addl $CHAR_PER_VEC, %ecx
> > > +# endif
> > > +
> > > + .p2align 4,, 4
> > > +L(ret_vec_x1_len):
> > > + /* If CHAR_PER_VEC < 64 we still need to tzcnt, otherwise it has
> > > + already been done. */
> > > +# if CHAR_PER_VEC < 64
> > > + tzcntq %rcx, %rcx
> > > +# endif
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_vec_x1_len_no_zfill)
> > > + /* Fall through (expectation) is copy len < buffer len. */
> > > + VMOVU %VZERO, ((VEC_SIZE)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > +L(ret_vec_x1_len_no_zfill_mov):
> > > + movl %ecx, %edx
> > > +# ifdef USE_AS_STPCPY
> > > + /* clear flags. */
> > > + xorl %ecx, %ecx
> > > +# endif
> > > +L(ret_vec_x1_len_no_zfill):
> > > + VMOVU ((VEC_SIZE)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rdx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > +# ifdef USE_AS_WCSCPY
> > > + adcq $0, %rdx
> > > + leaq (VEC_SIZE * 1)(%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + leal (VEC_SIZE)(%rdx), %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + ret
> > > +
> > > +
> > > + .p2align 4,, 10
> > > +L(ret_vec_x1):
> > > + bsf %VRCX, %VRCX
> > > +L(ret_vec_x1_no_bsf):
> > > + VMOVU %VZERO, ((VEC_SIZE)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > + subl %ecx, %edx
> > > + cmpl $CHAR_PER_VEC, %edx
> > > + jb L(ret_vec_x1_len_no_zfill_mov)
> > > + /* Fall through (expectation) is copy len < buffer len. */
> > > + VMOVU %VMM(1), (VEC_SIZE * 1)(%rdi)
> > > + VMOVU %VZERO, (VEC_SIZE * 1)(%rdi, %rcx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > + leaq (VEC_SIZE * 1)(%rdi, %rcx, CHAR_SIZE), %rax
> > > +# endif
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(last_4x_vec):
> > > + /* Seperate logic for CHAR_PER_VEC == 64 because we can do `andl
> > > + $(CHAR_PER_VEC * 4 - 1), %edx` with less code size just
> > > + using `movzbl`. */
> > > +# if CHAR_PER_VEC == 64
> > > + movzbl %dl, %edx
> > > +# else
> > > + andl $(CHAR_PER_VEC * 4 - 1), %edx
> > > +# endif
> > > + VMOVA (VEC_SIZE * 5)(%rsi), %VMM(1)
> > > + VPTESTN %VMM(1), %VMM(1), %k0
> > > + KMOV %k0, %VRCX
> > > + subq $-(VEC_SIZE * 4), %rsi
> > > + subq $-(VEC_SIZE * 4), %rdi
> > > + cmpl $(CHAR_PER_VEC * 2 - 1), %edx
> > > + jbe L(last_2x_vec)
> > > + .p2align 4,, 8
> > > +L(more_2x_vec):
> > > + VMOVU %VMM(1), (VEC_SIZE * 1)(%rdi)
> > > + test %VRCX, %VRCX
> > > + /* Must fill at least 2x VEC. */
> > > + jnz L(zfill_vec1)
> > > +
> > > + VMOVA (VEC_SIZE * 2)(%rsi), %VMM(2)
> > > + VMOVU %VMM(2), (VEC_SIZE * 2)(%rdi)
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + /* Must fill at least 1x VEC. */
> > > + jnz L(zfill_vec2)
> > > +
> > > + VMOVA (VEC_SIZE * 3)(%rsi), %VMM(3)
> > > + VPTESTN %VMM(3), %VMM(3), %k0
> > > + KMOV %k0, %VRCX
> > > +
> > > + /* Check if len is more 4x VEC. -1 because rdx is len - 1. */
> > > + cmpq $(CHAR_PER_VEC * 4 - 1), %rdx
> > > + ja L(more_4x_vec)
> > > +
> > > + subl $(CHAR_PER_VEC * 3), %edx
> > > + jb L(ret_vec_x3_len)
> > > +
> > > + test %VRCX, %VRCX
> > > + jnz L(ret_vec_x3)
> > > +
> > > + VPCMPEQ (VEC_SIZE * 4)(%rsi), %VZERO, %k0
> > > + VMOVU %VMM(3), (VEC_SIZE * 3)(%rdi)
> > > + KMOV %k0, %VRCX
> > > + tzcnt %VRCX, %VRCX
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_vec_x4_len_no_zfill)
> > > + /* Fall through (expectation) is copy len < buffer len. */
> > > + VMOVU %VZERO, ((VEC_SIZE * 4)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > + movl %ecx, %edx
> > > +L(ret_vec_x4_len_no_zfill):
> > > + VMOVU ((VEC_SIZE * 4)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rdx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE * 4)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > +# ifdef USE_AS_WCSCPY
> > > + adcq $0, %rdx
> > > + leaq (VEC_SIZE * 4)(%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + leal (VEC_SIZE * 4 + 0)(%rdx), %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + ret
> > > +
> > > +
> > > +L(ret_vec_x3_len):
> > > + addl $(CHAR_PER_VEC * 1), %edx
> > > + tzcnt %VRCX, %VRCX
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_vec_x3_len_no_zfill)
> > > + /* Fall through (expectation) is copy len < buffer len. */
> > > + VMOVU %VZERO, ((VEC_SIZE * 3)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > +L(ret_vec_x3_len_no_zfill_mov):
> > > + movl %ecx, %edx
> > > +# ifdef USE_AS_STPCPY
> > > + /* clear flags. */
> > > + xorl %ecx, %ecx
> > > +# endif
> > > + .p2align 4,, 4
> > > +L(ret_vec_x3_len_no_zfill):
> > > + VMOVU ((VEC_SIZE * 3)-(VEC_SIZE - CHAR_SIZE))(%rsi, %rdx, CHAR_SIZE), %VMM(0)
> > > + VMOVU %VMM(0), ((VEC_SIZE * 3)-(VEC_SIZE - CHAR_SIZE))(%rdi, %rdx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > +# ifdef USE_AS_WCSCPY
> > > + adcq $0, %rdx
> > > + leaq (VEC_SIZE * 3)(%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + leal (VEC_SIZE * 3 + 0)(%rdx), %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + ret
> > > +
> > > +
> > > + .p2align 4,, 8
> > > +L(ret_vec_x3):
> > > + bsf %VRCX, %VRCX
> > > + VMOVU %VZERO, (VEC_SIZE * 4 +(-(VEC_SIZE - CHAR_SIZE)))(%rdi, %rdx, CHAR_SIZE)
> > > + subl %ecx, %edx
> > > + jl L(ret_vec_x3_len_no_zfill_mov)
> > > + VMOVU %VMM(3), (VEC_SIZE * 3)(%rdi)
> > > + VMOVU %VZERO, (VEC_SIZE * 3)(%rdi, %rcx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > + leaq (VEC_SIZE * 3)(%rdi, %rcx, CHAR_SIZE), %rax
> > > +# endif
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(more_4x_vec):
> > > + VMOVU %VMM(3), (VEC_SIZE * 3)(%rdi)
> > > + test %VRCX, %VRCX
> > > + jnz L(zfill_vec3)
> > > +
> > > + VMOVA (VEC_SIZE * 4)(%rsi), %VMM(4)
> > > + VMOVU %VMM(4), (VEC_SIZE * 4)(%rdi)
> > > + VPTESTN %VMM(4), %VMM(4), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(zfill_vec4)
> > >
> > > -#define USE_AS_STRNCPY
> > > -#define STRCPY STRNCPY
> > > -#include "strcpy-evex.S"
> > > + /* Recheck length before aligning. */
> > > + cmpq $(CHAR_PER_VEC * 8 - 1), %rdx
> > > + jbe L(last_4x_vec)
> > > +
> > > + /* Align rsi to VEC_SIZE * 4, need to readjust rdx / rdi. */
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rsi, %rdx, CHAR_SIZE), %rdx
> > > +# else
> > > + addq %rsi, %rdx
> > > +# endif
> > > + subq %rsi, %rdi
> > > + subq $-(VEC_SIZE * 5), %rsi
> > > + andq $(VEC_SIZE * -4), %rsi
> > > +
> > > +
> > > + /* Load first half of the loop before entry. */
> > > + VMOVA (VEC_SIZE * 0 + 0)(%rsi), %VMM(0)
> > > + VMOVA (VEC_SIZE * 1 + 0)(%rsi), %VMM(1)
> > > + VMOVA (VEC_SIZE * 2 + 0)(%rsi), %VMM(2)
> > > + VMOVA (VEC_SIZE * 3 + 0)(%rsi), %VMM(3)
> > > +
> > > + VPMIN %VMM(0), %VMM(1), %VMM(4)
> > > + VPMIN %VMM(2), %VMM(3), %VMM(6)
> > > + VPTESTN %VMM(4), %VMM(4), %k2
> > > + VPTESTN %VMM(6), %VMM(6), %k4
> > > +
> > > +
> > > + /* Offset rsi by VEC_SIZE so that we can jump to
> > > + L(loop_last_4x_vec). */
> > > + addq $-(VEC_SIZE), %rsi
> > > + KORTEST %k2, %k4
> > > + jnz L(loop_4x_done)
> > > +
> > > + /* Store loop end in r9. */
> > > + leaq -(VEC_SIZE * 5 - CHAR_SIZE)(%rdx), %r9
> > > +
> > > + .p2align 4,, 11
> > > +L(loop_4x_vec):
> > > + VMOVU %VMM(0), (VEC_SIZE * 1 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(1), (VEC_SIZE * 2 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(2), (VEC_SIZE * 3 + 0)(%rdi, %rsi)
> > > + VMOVU %VMM(3), (VEC_SIZE * 4 + 0)(%rdi, %rsi)
> > > +
> > > + subq $(VEC_SIZE * -4), %rsi
> > > + cmpq %rsi, %r9
> > > + jbe L(loop_last_4x_vec)
> > > +
> > > + VMOVA (VEC_SIZE * 1 + 0)(%rsi), %VMM(0)
> > > + VMOVA (VEC_SIZE * 2 + 0)(%rsi), %VMM(1)
> > > + VMOVA (VEC_SIZE * 3 + 0)(%rsi), %VMM(2)
> > > + VMOVA (VEC_SIZE * 4 + 0)(%rsi), %VMM(3)
> > > +
> > > + VPMIN %VMM(0), %VMM(1), %VMM(4)
> > > + VPMIN %VMM(2), %VMM(3), %VMM(6)
> > > + VPTESTN %VMM(4), %VMM(4), %k2
> > > + VPTESTN %VMM(6), %VMM(6), %k4
> > > + KORTEST %k2, %k4
> > > + jz L(loop_4x_vec)
> > > +
> > > +L(loop_4x_done):
> > > + /* Restore rdx (length). */
> > > + subq %rsi, %rdx
> > > +# ifdef USE_AS_WCSCPY
> > > + shrq $2, %rdx
> > > +# endif
> > > + VMOVU %VMM(0), (VEC_SIZE * 1 + 0)(%rdi, %rsi)
> > > + /* Restore rdi (dst). */
> > > + addq %rsi, %rdi
> > > + VPTESTN %VMM(0), %VMM(0), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(zfill_vec1)
> > > +
> > > + VMOVU %VMM(1), (VEC_SIZE * 2 + 0)(%rdi)
> > > + KMOV %k2, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(zfill_vec2)
> > > +
> > > + VMOVU %VMM(2), (VEC_SIZE * 3 + 0)(%rdi)
> > > + VPTESTN %VMM(2), %VMM(2), %k0
> > > + KMOV %k0, %VRCX
> > > + test %VRCX, %VRCX
> > > + jnz L(zfill_vec3)
> > > +
> > > + VMOVU %VMM(3), (VEC_SIZE * 4 + 0)(%rdi)
> > > + KMOV %k4, %VRCX
> > > + // Zfill more....
> > > +
> > > + .p2align 4,, 4
> > > +L(zfill_vec4):
> > > + subq $(VEC_SIZE * -2), %rdi
> > > + addq $(CHAR_PER_VEC * -2), %rdx
> > > +L(zfill_vec2):
> > > + subq $(VEC_SIZE * -2), %rdi
> > > + addq $(CHAR_PER_VEC * -1), %rdx
> > > +L(zfill):
> > > + /* VRCX must be non-zero. */
> > > + bsf %VRCX, %VRCX
> > > +
> > > + /* Adjust length / dst for zfill. */
> > > + subq %rcx, %rdx
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rdi
> > > +# else
> > > + addq %rcx, %rdi
> > > +# endif
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > +L(zfill_from_page_cross):
> > > +
> > > + /* From here on out its just memset(rdi, 0, rdx). */
> > > + cmpq $CHAR_PER_VEC, %rdx
> > > + jb L(zfill_less_vec)
> > > +
> > > +L(zfill_more_1x_vec):
> > > + VMOVU %VZERO, (%rdi)
> > > + VMOVU %VZERO, (CHAR_SIZE - VEC_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > + cmpq $(CHAR_PER_VEC * 2 - 1), %rdx
> > > + ja L(zfill_more_2x_vec)
> > > +L(zfill_done0):
> > > + ret
> > > +
> > > + /* Coming from vec1/vec2 we must be able to zfill at least 2x
> > > + VEC. */
> > > + .p2align 4,, 8
> > > +L(zfill_vec3):
> > > + subq $(VEC_SIZE * -2), %rdi
> > > + addq $(CHAR_PER_VEC * -2), %rdx
> > > + .p2align 4,, 2
> > > +L(zfill_vec1):
> > > + bsfq %rcx, %rcx
> > > + /* rdi is currently dst - VEC_SIZE so add back VEC_SIZE here.
> > > + */
> > > + leaq VEC_SIZE(%rdi, %rcx, CHAR_SIZE), %rdi
> > > + subq %rcx, %rdx
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > +
> > > +
> > > + VMOVU %VZERO, (%rdi)
> > > + VMOVU %VZERO, (CHAR_SIZE - VEC_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > + cmpq $(CHAR_PER_VEC * 2), %rdx
> > > + jb L(zfill_done0)
> > > +L(zfill_more_2x_vec):
> > > + VMOVU %VZERO, (CHAR_SIZE - VEC_SIZE * 2)(%rdi, %rdx, CHAR_SIZE)
> > > + VMOVU %VZERO, (VEC_SIZE)(%rdi)
> > > + subq $(CHAR_PER_VEC * 4 - 1), %rdx
> > > + jbe L(zfill_done)
> > > +
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rdx
> > > +# else
> > > + addq %rdi, %rdx
> > > +# endif
> > > +
> > > + VMOVU %VZERO, (VEC_SIZE * 2)(%rdi)
> > > + VMOVU %VZERO, (VEC_SIZE * 3)(%rdi)
> > > +
> > > +
> > > + VMOVU %VZERO, (VEC_SIZE * 0 + 0)(%rdx)
> > > + VMOVU %VZERO, (VEC_SIZE * 1 + 0)(%rdx)
> > > +
> > > + subq $-(VEC_SIZE * 4), %rdi
> > > + cmpq %rdi, %rdx
> > > + jbe L(zfill_done)
> > > +
> > > + /* Align rdi and zfill loop. */
> > > + andq $-(VEC_SIZE), %rdi
> > > + .p2align 4,, 12
> > > +L(zfill_loop_4x_vec):
> > > + VMOVA %VZERO, (VEC_SIZE * 0)(%rdi)
> > > + VMOVA %VZERO, (VEC_SIZE * 1)(%rdi)
> > > + VMOVA %VZERO, (VEC_SIZE * 2)(%rdi)
> > > + VMOVA %VZERO, (VEC_SIZE * 3)(%rdi)
> > > + subq $-(VEC_SIZE * 4), %rdi
> > > + cmpq %rdi, %rdx
> > > + ja L(zfill_loop_4x_vec)
> > > +L(zfill_done):
> > > + ret
> > > +
> > > +
> > > + /* Less 1x VEC case if we are not using evex masked store. */
> > > +# if !USE_EVEX_MASKED_STORE
> > > + .p2align 4,, 8
> > > +L(copy_1x):
> > > + /* Special case for copy 1x. It can be handled quickly and many
> > > + buffer sizes have convenient alignment. */
> > > + VMOVU %VMM(0), (%rdi)
> > > + /* If no zeros then we are done. */
> > > + testl %ecx, %ecx
> > > + jz L(ret_1x_1x)
> > > +
> > > + /* Need to zfill, not we know that length <= CHAR_PER_VEC so we
> > > + only handle the small case here. */
> > > + bsf %VRCX, %VRCX
> > > +L(zfill_less_vec_no_bsf):
> > > + /* Adjust length / dst then just zfill less_vec. */
> > > + subq %rcx, %rdx
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rdi
> > > +# else
> > > + addq %rcx, %rdi
> > > +# endif
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > +
> > > +L(zfill_less_vec):
> > > + cmpl $((VEC_SIZE / 2) / CHAR_SIZE), %edx
> > > + jb L(zfill_less_half)
> > > +
> > > + VMOVU %VZERO_HALF, (%rdi)
> > > + VMOVU %VZERO_HALF, -((VEC_SIZE / 2)- CHAR_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +# ifdef USE_AS_STPCPY
> > > +L(ret_1x_1x):
> > > + leaq CHAR_SIZE(%rdi, %rdx, CHAR_SIZE), %rax
> > > + ret
> > > +# endif
> > > +
> > > +
> > > +# if VEC_SIZE == 64
> > > + .p2align 4,, 4
> > > +L(copy_32_63):
> > > + /* Overfill to avoid branches. */
> > > + VMOVU -(32 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %VMM_256(1)
> > > + VMOVU %VMM_256(0), (%rdi)
> > > + VMOVU %VMM_256(1), -(32 - CHAR_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > +
> > > + /* We are taking advantage of the fact that to be here we must
> > > + be writing null-term as (%rdi, %rcx) we have a byte of lee-
> > > + way for overwriting. */
> > > + cmpl %ecx, %edx
> > > + ja L(zfill_less_vec_no_bsf)
> > > +# ifndef USE_AS_STPCPY
> > > +L(ret_1x_1x):
> > > +# else
> > > +# ifdef USE_AS_WCSCPY
> > > + adcq $0, %rdx
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + movl %edx, %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + ret
> > > +# endif
> > > +
> > > + .p2align 4,, 4
> > > +L(copy_16_31):
> > > + /* Overfill to avoid branches. */
> > > + vmovdqu -(16 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %xmm1
> > > + VMOVU %VMM_128(0), (%rdi)
> > > + vmovdqu %xmm1, -(16 - CHAR_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > + cmpl %ecx, %edx
> > > +
> > > + /* Seperate logic depending on VEC_SIZE. If VEC_SIZE == 64 then
> > > + we have a larger copy block for 32-63 so this is just falls
> > > + through to zfill 16-31. If VEC_SIZE == 32 then we check for
> > > + full zfill of less 1x VEC. */
> > > +# if VEC_SIZE == 64
> > > + jbe L(ret_16_31)
> > > + subl %ecx, %edx
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rdi
> > > +# else
> > > + addq %rcx, %rdi
> > > +# endif
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > +L(zfill_less_half):
> > > +L(zfill_less_32):
> > > + cmpl $(16 / CHAR_SIZE), %edx
> > > + jb L(zfill_less_16)
> > > + VMOVU %VZERO_128, (%rdi)
> > > + VMOVU %VZERO_128, -(16 - CHAR_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > + ret
> > > +# endif
> > > +L(ret_16_31):
> > > +# ifdef USE_AS_STPCPY
> > > +# ifdef USE_AS_WCSCPY
> > > + adcq $0, %rdx
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + movl %edx, %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + ret
> > > +# else
> > > + /* VEC_SIZE == 32 begins. */
> > > + ja L(zfill_less_vec_no_bsf)
> > > +# ifndef USE_AS_STPCPY
> > > +L(ret_1x_1x):
> > > +# else
> > > +# ifdef USE_AS_WCSCPY
> > > + adcq $0, %rdx
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + movl %edx, %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# endif
> > > + ret
> > > +# endif
> > > +
> > > +
> > > + .p2align 4,, 4
> > > +L(copy_8_15):
> > > + /* Overfill to avoid branches. */
> > > + movq -(8 - CHAR_SIZE)(%rsi, %rdx, CHAR_SIZE), %rsi
> > > + vmovq %VMM_128(0), (%rdi)
> > > + movq %rsi, -(8 - CHAR_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_8_15)
> > > + subl %ecx, %edx
> > > +# ifdef USE_AS_WCSCPY
> > > + leaq (%rdi, %rcx, CHAR_SIZE), %rdi
> > > +# else
> > > + addq %rcx, %rdi
> > > +# endif
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > + .p2align 4,, 8
> > > +# if VEC_SIZE == 32
> > > +L(zfill_less_half):
> > > +# endif
> > > +L(zfill_less_16):
> > > + xorl %ecx, %ecx
> > > + cmpl $(8 / CHAR_SIZE), %edx
> > > + jb L(zfill_less_8)
> > > + movq %rcx, (%rdi)
> > > + movq %rcx, -(8 - CHAR_SIZE)(%rdi, %rdx, CHAR_SIZE)
> > > +# ifndef USE_AS_STPCPY
> > > +L(ret_8_15):
> > > +# endif
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(less_1x_vec):
> > > + je L(copy_1x)
> > > +
> > > + /* We will need `tzcnt` result for all other copy sizes. */
> > > + tzcnt %VRCX, %VRCX
> > > +# if VEC_SIZE == 64
> > > + cmpl $(32 / CHAR_SIZE), %edx
> > > + jae L(copy_32_63)
> > > +# endif
> > > +
> > > + cmpl $(16 / CHAR_SIZE), %edx
> > > + jae L(copy_16_31)
> > > +
> > > + cmpl $(8 / CHAR_SIZE), %edx
> > > + jae L(copy_8_15)
> > > +# ifdef USE_AS_WCSCPY
> > > + testl %ecx, %ecx
> > > + jz L(zfill_less_8_set_ret)
> > > +
> > > + movl (%rsi, %rdx, CHAR_SIZE), %esi
> > > + vmovd %VMM_128(0), (%rdi)
> > > + movl %esi, (%rdi, %rdx, CHAR_SIZE)
> > > +# ifdef USE_AS_STPCPY
> > > + cmpl %ecx, %edx
> > > +L(ret_8_15):
> > > + adcq $0, %rdx
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# endif
> > > + ret
> > > +L(zfill_less_8_set_ret):
> > > + xorl %ecx, %ecx
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > +L(zfill_less_8):
> > > + movl %ecx, (%rdi)
> > > + movl %ecx, (%rdi, %rdx, CHAR_SIZE)
> > > + ret
> > > +# else
> > > + cmpl $3, %edx
> > > + jb L(copy_0_3)
> > > + /* Overfill to avoid branches. */
> > > + movl -3(%rsi, %rdx), %esi
> > > + vmovd %VMM_128(0), (%rdi)
> > > + movl %esi, -3(%rdi, %rdx)
> > > + cmpl %ecx, %edx
> > > + jbe L(ret_4_7)
> > > + subq %rcx, %rdx
> > > + addq %rcx, %rdi
> > > +# ifdef USE_AS_STPCPY
> > > + movq %rdi, %rax
> > > +# endif
> > > + xorl %ecx, %ecx
> > > + .p2align 4,, 8
> > > +L(zfill_less_8):
> > > + cmpl $3, %edx
> > > + jb L(zfill_less_3)
> > > + movl %ecx, (%rdi)
> > > + movl %ecx, -3(%rdi, %rdx)
> > > +# ifdef USE_AS_STPCPY
> > > + ret
> > > +# endif
> > > +
> > > +L(ret_4_7):
> > > +# ifdef USE_AS_STPCPY
> > > +L(ret_8_15):
> > > + movl %edx, %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > + ret
> > > +
> > > + .p2align 4,, 4
> > > +L(zfill_less_3):
> > > + testl %edx, %edx
> > > + jz L(zfill_1)
> > > + movw %cx, (%rdi)
> > > +L(zfill_1):
> > > + movb %cl, (%rdi, %rdx)
> > > + ret
> > > +
> > > + .p2align 4,, 8
> > > +L(copy_0_3):
> > > + vmovd %VMM_128(0), %r8d
> > > + testl %edx, %edx
> > > + jz L(copy_1)
> > > + movw %r8w, (%rdi)
> > > + cmpl %ecx, %edx
> > > + ja L(zfill_from_1)
> > > + movzbl (%rsi, %rdx), %r8d
> > > +# ifdef USE_AS_STPCPY
> > > + movl %edx, %eax
> > > + adcq %rdi, %rax
> > > + movb %r8b, (%rdi, %rdx)
> > > + ret
> > > +# endif
> > > +
> > > +L(copy_1):
> > > +# ifdef USE_AS_STPCPY
> > > + movl %edx, %eax
> > > + cmpl %ecx, %edx
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# ifdef USE_AS_WCSCPY
> > > + vmovd %VMM_128(0), (%rdi)
> > > +# else
> > > + movb %r8b, (%rdi, %rdx)
> > > +# endif
> > > + ret
> > > +# endif
> > > +
> > > +
> > > +# ifndef USE_AS_WCSCPY
> > > + .p2align 4,, 8
> > > +L(zfill_from_1):
> > > +# ifdef USE_AS_STPCPY
> > > + leaq (%rdi, %rcx), %rax
> > > +# endif
> > > + movw $0, -1(%rdi, %rdx)
> > > + ret
> > > +# endif
> > > +
> > > + .p2align 4,, 4
> > > +L(zero_len):
> > > + incq %rdx
> > > + jne L(best_effort_strncpy)
> > > + movq %rdi, %rax
> > > + ret
> > > +# endif
> > > +
> > > +
> > > + .p2align 4,, 4
> > > + .p2align 6,, 8
> > > +L(page_cross):
> > > + movq %rsi, %rax
> > > + andq $(VEC_SIZE * -1), %rax
> > > + VPCMPEQ (%rax), %VZERO, %k0
> > > + KMOV %k0, %VRCX
> > > +# ifdef USE_AS_WCSCPY
> > > + movl %esi, %r8d
> > > + shrl $2, %r8d
> > > + andl $(CHAR_PER_VEC - 1), %r8d
> > > + shrx %VR8, %VRCX, %VRCX
> > > +# else
> > > + shrx %VRSI, %VRCX, %VRCX
> > > +# endif
> > > +
> > > + /* Compute amount of bytes we checked. */
> > > + subl %esi, %eax
> > > + andl $(VEC_SIZE - 1), %eax
> > > +# ifdef USE_AS_WCSCPY
> > > + shrl $2, %eax
> > > +# endif
> > > +
> > > + /* If rax > rdx then we are finishing the copy at the end of the
> > > + page. */
> > > + cmpq %rax, %rdx
> > > + jb L(page_cross_small)
> > > +
> > > +
> > > + /* If rcx is non-zero then continue. */
> > > + test %VRCX, %VRCX
> > > + jz L(page_cross_continue)
> > > +
> > > + /* We found zero-CHAR so need to copy then zfill (we know we
> > > + didn't cover all of length here). */
> > > + bsf %VRCX, %VRCX
> > > +L(movsb_and_zfill):
> > > + incl %ecx
> > > + subq %rcx, %rdx
> > > +# ifdef USE_AS_STPCPY
> > > + leaq -CHAR_SIZE(%rdi, %rcx, CHAR_SIZE), %rax
> > > +# else
> > > + movq %rdi, %rax
> > > +# endif
> > > +
> > > + REP_MOVS
> > > +# ifdef USE_AS_WCSCPY
> > > + movl $0, (%rdi)
> > > +# else
> > > + movb $0, (%rdi)
> > > +# endif
> > > + jmp L(zfill_from_page_cross)
> > > +
> > > +L(page_cross_small):
> > > + tzcnt %VRCX, %VRCX
> > > + cmpl %ecx, %edx
> > > + jbe L(page_cross_copy_only)
> > > +
> > > + /* Do a zfill of the tail before copying. */
> > > + movq %rdi, %r9
> > > + xorl %eax, %eax
> > > +
> > > + movl %ecx, %r8d
> > > +
> > > + subl %ecx, %edx
> > > + leaq CHAR_SIZE(%rdi, %rcx, CHAR_SIZE), %rdi
> > > + movl %edx, %ecx
> > > + REP_STOS
> > > + movq %r9, %rdi
> > > + movl %r8d, %edx
> > > +L(page_cross_copy_only):
> > > + leal 1(%rdx), %ecx
> > > +# ifdef USE_AS_STPCPY
> > > +# ifdef USE_AS_WCSCPY
> > > + adcl $0, %edx
> > > + leaq (%rdi, %rdx, CHAR_SIZE), %rax
> > > +# else
> > > + movl %edx, %eax
> > > + adcq %rdi, %rax
> > > +# endif
> > > +# else
> > > + movq %rdi, %rax
> > > +# endif
> > > + REP_MOVS
> > > + ret
> > > +
> > > +
> > > +L(best_effort_strncpy):
> > > + movq %rdx, %rcx
> > > + xorl %eax, %eax
> > > + movq %rdi, %r8
> > > + /* The length is >= 2^63. We very much so expect to segfault at
> > > + rep stos. If that doesn't happen then just strcpy to finish.
> > > + */
> > > + REP_STOS
> > > + movq %r8, %rdi
> > > + jmp OVERFLOW_STRCPY
> > > +END(STRNCPY)
> > > +#endif
> > > diff --git a/sysdeps/x86_64/multiarch/strncpy-or-cat-overflow-def.h b/sysdeps/x86_64/multiarch/strncpy-or-cat-overflow-def.h
> > > new file mode 100644
> > > index 0000000000..d5ff4cbe50
> > > --- /dev/null
> > > +++ b/sysdeps/x86_64/multiarch/strncpy-or-cat-overflow-def.h
> >
> > Please add a copyright notice.
> >
> > > @@ -0,0 +1,65 @@
> > > +#ifndef _STRNCPY_OR_CAT_OVERFLOW_DEF_H_
> > > +#define _STRNCPY_OR_CAT_OVERFLOW_DEF_H_ 1
> > > +
> > > +#if defined USE_MULTIARCH && IS_IN(libc)
> > > +# define UNDERSCORES __
> > > +# ifdef USE_WITH_SSE2
> > > +# define ISA_EXT _sse2
> > > +# elif defined USE_WITH_AVX
> > > +# ifdef USE_WITH_RTM
> > > +# define ISA_EXT _avx_rtm
> > > +# else
> > > +# define ISA_EXT _avx
> > > +# endif
> > > +# elif defined USE_WITH_AVX2
> >
> > Do we have a function with both AVX and AVX2 versions? If not, should
> > keep just 1.
> >
> > > +# ifdef USE_WITH_RTM
> > > +# define ISA_EXT _avx2_rtm
> > > +# else
> > > +# define ISA_EXT _avx2
> > > +# endif
> > > +
> > > +# elif defined USE_WITH_EVEX256
> > > +# define ISA_EXT _evex
> > > +# elif defined USE_WITH_EVEX512
> > > +# define ISA_EXT _evex512
> > > +# endif
> > > +#else
> > > +# define UNDERSCORES
> > > +# define ISA_EXT
> > > +#endif
> > > +
> > > +#ifdef USE_AS_WCSCPY
> > > +# define STRCPY_PREFIX wc
> > > +# define STRCAT_PREFIX wcs
> > > +# ifdef USE_AS_STPCPY
> > > +# define STRCPY_POSTFIX pcpy
> > > +# else
> > > +# define STRCPY_POSTFIX scpy
> > > +# endif
> > > +#else
> > > +# define STRCPY_PREFIX st
> > > +# define STRCAT_PREFIX str
> > > +# ifdef USE_AS_STPCPY
> > > +# define STRCPY_POSTFIX pcpy
> > > +# else
> > > +# define STRCPY_POSTFIX rcpy
> > > +# endif
> > > +#endif
> > > +#define STRCAT_POSTFIX cat
> > > +
> > > +#define PRIMITIVE_OF_NAMER(underscores, prefix, postfix, ext) \
> > > + underscores##prefix##postfix##ext
> > > +
> > > +#define OF_NAMER(...) PRIMITIVE_OF_NAMER (__VA_ARGS__)
> > > +
> > > +#ifndef OVERFLOW_STRCPY
> > > +# define OVERFLOW_STRCPY \
> > > + OF_NAMER (UNDERSCORES, STRCPY_PREFIX, STRCPY_POSTFIX, ISA_EXT)
> > > +#endif
> > > +
> > > +#ifndef OVERFLOW_STRCAT
> > > +# define OVERFLOW_STRCAT \
> > > + OF_NAMER (UNDERSCORES, STRCAT_PREFIX, STRCAT_POSTFIX, ISA_EXT)
> > > +#endif
> > > +
> > > +#endif
> > > --
> > > 2.34.1
> > >
> >
> > H.J.
--
H.J.
next prev parent reply other threads:[~2022-11-04 22:47 UTC|newest]
Thread overview: 42+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-03 8:53 [PATCH v1 1/4] benchtests: Make str{n}{cat|cpy} benchmarks output json Noah Goldstein
2022-11-03 8:53 ` [PATCH v1 2/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-evex functions Noah Goldstein
2022-11-03 8:55 ` Noah Goldstein
2022-11-04 23:04 ` [PATCH v4 1/4] " Noah Goldstein
2022-11-04 23:04 ` [PATCH v4 2/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-avx2 functions Noah Goldstein
2022-11-04 23:04 ` [PATCH v4 3/4] x86: Add evex optimized functions for the wchar_t strcpy family Noah Goldstein
2022-11-04 23:04 ` [PATCH v4 4/4] x86: Add avx2 " Noah Goldstein
2022-11-04 23:34 ` [PATCH v4 1/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-evex functions H.J. Lu
2022-11-09 1:38 ` [PATCH v5 " Noah Goldstein
2022-11-09 1:38 ` [PATCH v5 2/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-avx2 functions Noah Goldstein
2022-11-09 3:00 ` H.J. Lu
2022-11-09 1:38 ` [PATCH v5 3/4] x86: Add evex optimized functions for the wchar_t strcpy family Noah Goldstein
2022-11-09 3:01 ` H.J. Lu
2022-11-09 1:38 ` [PATCH v5 4/4] x86: Add avx2 " Noah Goldstein
2022-11-09 3:01 ` H.J. Lu
2022-11-09 3:00 ` [PATCH v5 1/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-evex functions H.J. Lu
2022-11-03 8:53 ` [PATCH v1 3/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-avx2 functions Noah Goldstein
2022-11-03 8:55 ` Noah Goldstein
2022-11-03 8:53 ` [PATCH v1 4/4] x86: Add optimized functions for the wide-character strcpy family Noah Goldstein
2022-11-03 9:06 ` [PATCH v1 1/4] benchtests: Make str{n}{cat|cpy} benchmarks output json Noah Goldstein
2022-11-04 8:20 ` [PATCH v2 " Noah Goldstein
2022-11-04 8:20 ` [PATCH v2 2/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-evex functions Noah Goldstein
2022-11-04 16:33 ` H.J. Lu
2022-11-04 20:20 ` Noah Goldstein
2022-11-04 8:20 ` [PATCH v2 3/4] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-avx2 functions Noah Goldstein
2022-11-04 16:45 ` H.J. Lu
2022-11-04 20:21 ` Noah Goldstein
2022-11-04 8:20 ` [PATCH v2 4/4] x86: Add optimized functions for the wide-character strcpy family Noah Goldstein
2022-11-04 16:47 ` H.J. Lu
2022-11-04 20:22 ` Noah Goldstein
2022-11-04 16:26 ` [PATCH v2 1/4] benchtests: Make str{n}{cat|cpy} benchmarks output json H.J. Lu
2022-11-04 20:13 ` [PATCH v3 1/5] " Noah Goldstein
2022-11-04 20:13 ` [PATCH v3 2/5] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-evex functions Noah Goldstein
2022-11-04 21:46 ` H.J. Lu
2022-11-04 22:27 ` Noah Goldstein
2022-11-04 22:47 ` H.J. Lu [this message]
2022-11-04 23:06 ` Noah Goldstein
2022-11-04 20:13 ` [PATCH v3 3/5] x86: Optimize and shrink st{r|p}{n}{cat|cpy}-avx2 functions Noah Goldstein
2022-11-04 20:13 ` [PATCH v3 4/5] x86: Add evex optimized functions for the wchar_t strcpy family Noah Goldstein
2022-11-04 20:13 ` [PATCH v3 5/5] x86: Add avx2 " Noah Goldstein
2022-11-04 21:01 ` [PATCH v3 1/5] benchtests: Make str{n}{cat|cpy} benchmarks output json H.J. Lu
2022-11-04 21:24 ` Noah Goldstein
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