[v3] string: Use builtins for ffs and ffsll
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| Context |
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| redhat-pt-bot/TryBot-apply_patch |
success
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Patch applied to master at the time it was sent
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| redhat-pt-bot/TryBot-32bit |
success
|
Build for i686
|
| linaro-tcwg-bot/tcwg_glibc_build--master-aarch64 |
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|
Testing passed
|
| linaro-tcwg-bot/tcwg_glibc_check--master-arm |
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|
Testing passed
|
| linaro-tcwg-bot/tcwg_glibc_check--master-aarch64 |
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|
Testing passed
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| linaro-tcwg-bot/tcwg_glibc_build--master-arm |
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Testing passed
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Commit Message
It allows to remove a lot of arch-specific implementations.
Checked on x86_64, aarch64, powerpc64.
--
Changes from v2:
* Fix arm math-use-builtins-ffs.h placement.
---
string/ffs.c | 6 +-
string/ffsll.c | 10 ++-
sysdeps/aarch64/math-use-builtins-ffs.h | 2 +
sysdeps/alpha/alphaev67/ffs.S | 51 ------------
sysdeps/alpha/alphaev67/ffsll.S | 44 ----------
sysdeps/alpha/ffs.S | 90 ---------------------
sysdeps/alpha/ffsll.S | 1 -
sysdeps/alpha/math-use-builtins-ffs.h | 7 ++
sysdeps/arc/math-use-builtins-ffs.h | 2 +
sysdeps/arm/armv6t2/ffs.S | 36 ---------
sysdeps/arm/armv6t2/ffsll.S | 50 ------------
sysdeps/arm/armv6t2/math-use-builtins-ffs.h | 2 +
sysdeps/generic/math-use-builtins-ffs.h | 2 +
sysdeps/generic/math-use-builtins.h | 1 +
sysdeps/i386/ffs.c | 49 -----------
sysdeps/i386/i686/ffs.c | 47 -----------
sysdeps/i386/math-use-builtins-ffs.h | 2 +
sysdeps/ia64/math-use-builtins-ffs.h | 2 +
sysdeps/m68k/ffs.c | 46 -----------
sysdeps/m68k/math-use-builtins-ffs.h | 7 ++
sysdeps/powerpc/ffs.c | 46 -----------
sysdeps/powerpc/math-use-builtins-ffs.h | 6 ++
sysdeps/powerpc/powerpc64/ffsll.c | 36 ---------
sysdeps/s390/ffs.c | 69 ----------------
sysdeps/x86_64/ffs.c | 38 ---------
sysdeps/x86_64/ffsll.c | 41 ----------
sysdeps/x86_64/math-use-builtins-ffs.h | 2 +
sysdeps/x86_64/x32/ffs.c | 4 -
28 files changed, 48 insertions(+), 651 deletions(-)
create mode 100644 sysdeps/aarch64/math-use-builtins-ffs.h
delete mode 100644 sysdeps/alpha/alphaev67/ffs.S
delete mode 100644 sysdeps/alpha/alphaev67/ffsll.S
delete mode 100644 sysdeps/alpha/ffs.S
delete mode 100644 sysdeps/alpha/ffsll.S
create mode 100644 sysdeps/alpha/math-use-builtins-ffs.h
create mode 100644 sysdeps/arc/math-use-builtins-ffs.h
delete mode 100644 sysdeps/arm/armv6t2/ffs.S
delete mode 100644 sysdeps/arm/armv6t2/ffsll.S
create mode 100644 sysdeps/arm/armv6t2/math-use-builtins-ffs.h
create mode 100644 sysdeps/generic/math-use-builtins-ffs.h
delete mode 100644 sysdeps/i386/ffs.c
delete mode 100644 sysdeps/i386/i686/ffs.c
create mode 100644 sysdeps/i386/math-use-builtins-ffs.h
create mode 100644 sysdeps/ia64/math-use-builtins-ffs.h
delete mode 100644 sysdeps/m68k/ffs.c
create mode 100644 sysdeps/m68k/math-use-builtins-ffs.h
delete mode 100644 sysdeps/powerpc/ffs.c
create mode 100644 sysdeps/powerpc/math-use-builtins-ffs.h
delete mode 100644 sysdeps/powerpc/powerpc64/ffsll.c
delete mode 100644 sysdeps/s390/ffs.c
delete mode 100644 sysdeps/x86_64/ffs.c
delete mode 100644 sysdeps/x86_64/ffsll.c
create mode 100644 sysdeps/x86_64/math-use-builtins-ffs.h
delete mode 100644 sysdeps/x86_64/x32/ffs.c
Comments
On 8/25/23 12:30, Adhemerval Zanella via Libc-alpha wrote:
> It allows to remove a lot of arch-specific implementations.
The ffs/ffsll issue came up again in downstream discussions.
I read through the initial patch, the following discussion, and points
from Florian, Andreas, Wilco, Richard, Andrew etc. It seems to me that
there is consensus that complete removal is the best overall long term
option.
Generated code for x86_64 looks like this (without CET on):
0000000000095460 <__ffs>:
__GI___ffs():
/mnt/ssd/carlos/src/glibc-review/string/ffs.c:29
95460: 0f bc c7 bsf %edi,%eax
95463: ba ff ff ff ff mov $0xffffffff,%edx
95468: 0f 44 c2 cmove %edx,%eax
9546b: 83 c0 01 add $0x1,%eax
/mnt/ssd/carlos/src/glibc-review/string/ffs.c:49
9546e: c3 ret
__GI_ffs():
9546f: 90 nop
0000000000095470 <ffsl>:
__ffsll():
/mnt/ssd/carlos/src/glibc-review/string/ffsll.c:30
95470: 48 0f bc ff bsf %rdi,%rdi
95474: 48 c7 c0 ff ff ff ff mov $0xffffffffffffffff,%rax
9547b: 48 0f 44 f8 cmove %rax,%rdi
9547f: 8d 47 01 lea 0x1(%rdi),%eax
/mnt/ssd/carlos/src/glibc-review/string/ffsll.c:39
95482: c3 ret
95483: 66 2e 0f 1f 84 00 00 cs nopw 0x0(%rax,%rax,1)
9548a: 00 00 00
9548d: 0f 1f 00 nopl (%rax)
This looks about what I would expect.
Performance critical applications should allow the compiler to use the
builtin and much much more.
OK for glibc 2.40 (not the upcoming 2.39 release).
Reviewed-by: Carlos O'Donell <carlos@redhat.com>
> Checked on x86_64, aarch64, powerpc64.
> --
> Changes from v2:
> * Fix arm math-use-builtins-ffs.h placement.
> ---
> string/ffs.c | 6 +-
> string/ffsll.c | 10 ++-
> sysdeps/aarch64/math-use-builtins-ffs.h | 2 +
> sysdeps/alpha/alphaev67/ffs.S | 51 ------------
> sysdeps/alpha/alphaev67/ffsll.S | 44 ----------
> sysdeps/alpha/ffs.S | 90 ---------------------
> sysdeps/alpha/ffsll.S | 1 -
> sysdeps/alpha/math-use-builtins-ffs.h | 7 ++
> sysdeps/arc/math-use-builtins-ffs.h | 2 +
> sysdeps/arm/armv6t2/ffs.S | 36 ---------
> sysdeps/arm/armv6t2/ffsll.S | 50 ------------
> sysdeps/arm/armv6t2/math-use-builtins-ffs.h | 2 +
> sysdeps/generic/math-use-builtins-ffs.h | 2 +
> sysdeps/generic/math-use-builtins.h | 1 +
> sysdeps/i386/ffs.c | 49 -----------
> sysdeps/i386/i686/ffs.c | 47 -----------
> sysdeps/i386/math-use-builtins-ffs.h | 2 +
> sysdeps/ia64/math-use-builtins-ffs.h | 2 +
> sysdeps/m68k/ffs.c | 46 -----------
> sysdeps/m68k/math-use-builtins-ffs.h | 7 ++
> sysdeps/powerpc/ffs.c | 46 -----------
> sysdeps/powerpc/math-use-builtins-ffs.h | 6 ++
> sysdeps/powerpc/powerpc64/ffsll.c | 36 ---------
> sysdeps/s390/ffs.c | 69 ----------------
> sysdeps/x86_64/ffs.c | 38 ---------
> sysdeps/x86_64/ffsll.c | 41 ----------
> sysdeps/x86_64/math-use-builtins-ffs.h | 2 +
> sysdeps/x86_64/x32/ffs.c | 4 -
> 28 files changed, 48 insertions(+), 651 deletions(-)
> create mode 100644 sysdeps/aarch64/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/alpha/alphaev67/ffs.S
> delete mode 100644 sysdeps/alpha/alphaev67/ffsll.S
> delete mode 100644 sysdeps/alpha/ffs.S
> delete mode 100644 sysdeps/alpha/ffsll.S
> create mode 100644 sysdeps/alpha/math-use-builtins-ffs.h
> create mode 100644 sysdeps/arc/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/arm/armv6t2/ffs.S
> delete mode 100644 sysdeps/arm/armv6t2/ffsll.S
> create mode 100644 sysdeps/arm/armv6t2/math-use-builtins-ffs.h
> create mode 100644 sysdeps/generic/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/i386/ffs.c
> delete mode 100644 sysdeps/i386/i686/ffs.c
> create mode 100644 sysdeps/i386/math-use-builtins-ffs.h
> create mode 100644 sysdeps/ia64/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/m68k/ffs.c
> create mode 100644 sysdeps/m68k/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/powerpc/ffs.c
> create mode 100644 sysdeps/powerpc/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/powerpc/powerpc64/ffsll.c
> delete mode 100644 sysdeps/s390/ffs.c
> delete mode 100644 sysdeps/x86_64/ffs.c
> delete mode 100644 sysdeps/x86_64/ffsll.c
> create mode 100644 sysdeps/x86_64/math-use-builtins-ffs.h
> delete mode 100644 sysdeps/x86_64/x32/ffs.c
>
> diff --git a/string/ffs.c b/string/ffs.c
> index bf58f0b7ca..8302ae8420 100644
> --- a/string/ffs.c
> +++ b/string/ffs.c
> @@ -18,13 +18,16 @@
> #include <limits.h>
> #define ffsl __something_else
> #include <string.h>
> -
> #undef ffs
> +#include <math-use-builtins.h>
>
> /* Find the first bit set in I. */
> int
> __ffs (int i)
> {
> +#if USE_FFS_BUILTIN
> + return __builtin_ffs (i);
> +#else
> static const unsigned char table[] =
> {
> 0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
> @@ -42,6 +45,7 @@ __ffs (int i)
> a = x <= 0xffff ? (x <= 0xff ? 0 : 8) : (x <= 0xffffff ? 16 : 24);
>
> return table[x >> a] + a;
> +#endif
> }
> weak_alias (__ffs, ffs)
> libc_hidden_def (__ffs)
> diff --git a/string/ffsll.c b/string/ffsll.c
> index 0cc461a1cf..2315fe1bd7 100644
> --- a/string/ffsll.c
> +++ b/string/ffsll.c
> @@ -18,20 +18,26 @@
> #include <limits.h>
> #define ffsl __something_else
> #include <string.h>
> -
> #undef ffsll
> +#include <math-use-builtins.h>
> +#include <libc-diag.h>
>
> /* Find the first bit set in I. */
> int
> -ffsll (long long int i)
> +__ffsll (long long int i)
> {
> +#if USE_FFSLL_BUILTIN
> + return __builtin_ffsll (i);
> +#else
> unsigned long long int x = i & -i;
>
> if (x <= 0xffffffff)
> return ffs (i);
> else
> return 32 + ffs (i >> 32);
> +#endif
> }
> +weak_alias (__ffsll, ffsll)
>
> #if ULONG_MAX != UINT_MAX
> #undef ffsl
> diff --git a/sysdeps/aarch64/math-use-builtins-ffs.h b/sysdeps/aarch64/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..a83bb15414
> --- /dev/null
> +++ b/sysdeps/aarch64/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 1
> +#define USE_FFSLL_BUILTIN 1
> diff --git a/sysdeps/alpha/alphaev67/ffs.S b/sysdeps/alpha/alphaev67/ffs.S
> deleted file mode 100644
> index 48361bd8c5..0000000000
> --- a/sysdeps/alpha/alphaev67/ffs.S
> +++ /dev/null
> @@ -1,51 +0,0 @@
> -/* Copyright (C) 2000-2023 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/>. */
> -
> -/* Finds the first bit set in an integer. */
> -
> -#include <sysdep.h>
> -
> - .arch ev6
> - .set noreorder
> - .set noat
> -
> -
> -ENTRY(__ffs)
> -#ifdef PROF
> - ldgp gp, 0(pv)
> - lda AT, _mcount
> - jsr AT, (AT), _mcount
> - .prologue 1
> -#else
> - .prologue 0
> -#endif
> -
> - zap $16, 0xF0, $16
> - cttz $16, $0
> - addq $0, 1, $0
> - cmoveq $16, 0, $0
> -
> - nop
> - nop
> - nop
> - ret
> -
> -END(__ffs)
> -
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> diff --git a/sysdeps/alpha/alphaev67/ffsll.S b/sysdeps/alpha/alphaev67/ffsll.S
> deleted file mode 100644
> index 52f406ec32..0000000000
> --- a/sysdeps/alpha/alphaev67/ffsll.S
> +++ /dev/null
> @@ -1,44 +0,0 @@
> -/* Copyright (C) 2000-2023 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/>. */
> -
> -/* Finds the first bit set in a long. */
> -
> -#include <sysdep.h>
> -
> - .arch ev6
> - .set noreorder
> - .set noat
> -
> -ENTRY(ffsl)
> -#ifdef PROF
> - ldgp gp, 0(pv)
> - lda AT, _mcount
> - jsr AT, (AT), _mcount
> - .prologue 1
> -#else
> - .prologue 0
> -#endif
> -
> - cttz $16, $0
> - addq $0, 1, $0
> - cmoveq $16, 0, $0
> - ret
> -
> -END(ffsl)
> -
> -weak_extern (ffsl)
> -weak_alias (ffsl, ffsll)
> diff --git a/sysdeps/alpha/ffs.S b/sysdeps/alpha/ffs.S
> deleted file mode 100644
> index 047fd60352..0000000000
> --- a/sysdeps/alpha/ffs.S
> +++ /dev/null
> @@ -1,90 +0,0 @@
> -/* Copyright (C) 1996-2023 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/>. */
> -
> -/* Finds the first bit set in an integer. Optimized for the Alpha
> - architecture. */
> -
> -#include <sysdep.h>
> -
> - .set noreorder
> - .set noat
> -
> -
> -ENTRY(__ffs)
> -#ifdef PROF
> - ldgp gp, 0(pv)
> - lda AT, _mcount
> - jsr AT, (AT), _mcount
> - .prologue 1
> - zap $16, 0xF0, $16
> - br $ffsl..ng
> -#else
> - .prologue 0
> - zap $16, 0xF0, $16
> - # FALLTHRU
> -#endif
> -END(__ffs)
> -
> - .align 4
> -ENTRY(ffsl)
> -#ifdef PROF
> - ldgp gp, 0(pv)
> - lda AT, _mcount
> - jsr AT, (AT), _mcount
> - .prologue 1
> -$ffsl..ng:
> -#else
> - .prologue 0
> -#endif
> - not $16, $1 # e0 :
> - ldi $2, -1 # .. e1 :
> - cmpbge $1, $2, $3 # e0 : bit N == 1 for byte N == 0
> - clr $0 # .. e1 :
> - addq $3, 1, $4 # e0 :
> - bic $4, $3, $3 # e1 : bit N == 1 for first byte N != 0
> - and $3, 0xF0, $4 # e0 :
> - and $3, 0xCC, $5 # .. e1 :
> - and $3, 0xAA, $6 # e0 :
> - cmovne $4, 4, $0 # .. e1 :
> - cmovne $5, 2, $5 # e0 :
> - cmovne $6, 1, $6 # .. e1 :
> - addl $0, $5, $0 # e0 :
> - addl $0, $6, $0 # e1 : $0 == N
> - extbl $16, $0, $1 # e0 : $1 == byte N
> - ldi $2, 1 # .. e1 :
> - negq $1, $3 # e0 :
> - and $3, $1, $3 # e1 : bit N == least bit set of byte N
> - and $3, 0xF0, $4 # e0 :
> - and $3, 0xCC, $5 # .. e1 :
> - and $3, 0xAA, $6 # e0 :
> - cmovne $4, 5, $2 # .. e1 :
> - cmovne $5, 2, $5 # e0 :
> - cmovne $6, 1, $6 # .. e1 :
> - s8addl $0, $2, $0 # e0 : mult byte ofs by 8 and sum
> - addl $5, $6, $5 # .. e1 :
> - addl $0, $5, $0 # e0 :
> - nop # .. e1 :
> - cmoveq $16, 0, $0 # e0 : trap input == 0 case.
> - ret # .. e1 : 18
> -
> -END(ffsl)
> -
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> -weak_extern (ffsl)
> -weak_alias (ffsl, ffsll)
> diff --git a/sysdeps/alpha/ffsll.S b/sysdeps/alpha/ffsll.S
> deleted file mode 100644
> index b2f46d899c..0000000000
> --- a/sysdeps/alpha/ffsll.S
> +++ /dev/null
> @@ -1 +0,0 @@
> -/* This function is defined in ffs.S. */
> diff --git a/sysdeps/alpha/math-use-builtins-ffs.h b/sysdeps/alpha/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..9925e374ac
> --- /dev/null
> +++ b/sysdeps/alpha/math-use-builtins-ffs.h
> @@ -0,0 +1,7 @@
> +#ifdef __alpha_cix__
> +# define USE_FFS_BUILTIN 1
> +# define USE_FFSLL_BUILTIN 1
> +#else
> +# define USE_FFS_BUILTIN 0
> +# define USE_FFSLL_BUILTIN 0
> +#endif
> diff --git a/sysdeps/arc/math-use-builtins-ffs.h b/sysdeps/arc/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..c0f108c264
> --- /dev/null
> +++ b/sysdeps/arc/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 1
> +#define USE_FFSLL_BUILTIN 0
> diff --git a/sysdeps/arm/armv6t2/ffs.S b/sysdeps/arm/armv6t2/ffs.S
> deleted file mode 100644
> index 870957a4bb..0000000000
> --- a/sysdeps/arm/armv6t2/ffs.S
> +++ /dev/null
> @@ -1,36 +0,0 @@
> -/* ffs -- find first set bit in an int, from least significant end.
> - Copyright (C) 2013-2023 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 <sysdep.h>
> -
> - .syntax unified
> - .text
> -
> -ENTRY (__ffs)
> - cmp r0, #0
> - rbit r0, r0
> - itt ne
> - clzne r0, r0
> - addne r0, r0, #1
> - bx lr
> -END (__ffs)
> -
> -weak_alias (__ffs, ffs)
> -weak_alias (__ffs, ffsl)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> diff --git a/sysdeps/arm/armv6t2/ffsll.S b/sysdeps/arm/armv6t2/ffsll.S
> deleted file mode 100644
> index bc3cbf81b0..0000000000
> --- a/sysdeps/arm/armv6t2/ffsll.S
> +++ /dev/null
> @@ -1,50 +0,0 @@
> -/* ffsll -- find first set bit in a long long, from least significant end.
> - Copyright (C) 2013-2023 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 <sysdep.h>
> -
> - .syntax unified
> - .text
> -
> -ENTRY (ffsll)
> - @ If low part is 0, operate on the high part. Ensure that the
> - @ word on which we operate is in r0. Set r2 to the bit offset
> - @ of the word being considered. Set the flags for the word
> - @ being operated on.
> -#ifdef __ARMEL__
> - cmp r0, #0
> - itee ne
> - movne r2, #0
> - moveq r2, #32
> - movseq r0, r1
> -#else
> - cmp r1, #0
> - ittee ne
> - movne r2, #0
> - movne r0, r1
> - moveq r2, #32
> - cmpeq r0, #0
> -#endif
> - @ Perform the ffs on r0.
> - rbit r0, r0
> - ittt ne
> - clzne r0, r0
> - addne r2, r2, #1
> - addne r0, r0, r2
> - bx lr
> -END (ffsll)
> diff --git a/sysdeps/arm/armv6t2/math-use-builtins-ffs.h b/sysdeps/arm/armv6t2/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..c0f108c264
> --- /dev/null
> +++ b/sysdeps/arm/armv6t2/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 1
> +#define USE_FFSLL_BUILTIN 0
> diff --git a/sysdeps/generic/math-use-builtins-ffs.h b/sysdeps/generic/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..add8537470
> --- /dev/null
> +++ b/sysdeps/generic/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 0
> +#define USE_FFSLL_BUILTIN 0
> diff --git a/sysdeps/generic/math-use-builtins.h b/sysdeps/generic/math-use-builtins.h
> index 04b1d0d5ab..038eb2c523 100644
> --- a/sysdeps/generic/math-use-builtins.h
> +++ b/sysdeps/generic/math-use-builtins.h
> @@ -40,5 +40,6 @@
> #include <math-use-builtins-lrint.h>
> #include <math-use-builtins-llrint.h>
> #include <math-use-builtins-logb.h>
> +#include <math-use-builtins-ffs.h>
>
> #endif /* MATH_USE_BUILTINS_H */
> diff --git a/sysdeps/i386/ffs.c b/sysdeps/i386/ffs.c
> deleted file mode 100644
> index b8e798420b..0000000000
> --- a/sysdeps/i386/ffs.c
> +++ /dev/null
> @@ -1,49 +0,0 @@
> -/* ffs -- find first set bit in a word, counted from least significant end.
> - For Intel 80x86, x>=3.
> - This file is part of the GNU C Library.
> - Copyright (C) 1991-2023 Free Software Foundation, Inc.
> -
> - 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/>. */
> -
> -#define ffsl __something_else
> -#include <string.h>
> -
> -#undef ffs
> -
> -#ifdef __GNUC__
> -
> -int
> -__ffs (int x)
> -{
> - int cnt;
> - int tmp;
> -
> - asm ("xorl %0,%0\n" /* Set CNT to zero. */
> - "bsfl %2,%1\n" /* Count low bits in X and store in %1. */
> - "jz 1f\n" /* Jump if OK, i.e. X was non-zero. */
> - "leal 1(%1),%0\n" /* Return bsfl-result plus one on %0. */
> - "1:" : "=&a" (cnt), "=r" (tmp) : "rm" (x));
> -
> - return cnt;
> -}
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> -#undef ffsl
> -weak_alias (__ffs, ffsl)
> -
> -#else
> -#include <string/ffs.c>
> -#endif
> diff --git a/sysdeps/i386/i686/ffs.c b/sysdeps/i386/i686/ffs.c
> deleted file mode 100644
> index a522077cfe..0000000000
> --- a/sysdeps/i386/i686/ffs.c
> +++ /dev/null
> @@ -1,47 +0,0 @@
> -/* ffs -- find first set bit in a word, counted from least significant end.
> - For Intel 80x86, x>=6.
> - This file is part of the GNU C Library.
> - Copyright (C) 1991-2023 Free Software Foundation, Inc.
> -
> - 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/>. */
> -
> -#define ffsl __something_else
> -#include <string.h>
> -
> -#undef ffs
> -
> -#ifdef __GNUC__
> -
> -int
> -__ffs (int x)
> -{
> - int cnt;
> - int tmp;
> -
> - asm ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
> - "cmovel %1,%0\n" /* If number was zero, use -1 as result. */
> - : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
> -
> - return cnt + 1;
> -}
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> -#undef ffsl
> -weak_alias (__ffs, ffsl)
> -
> -#else
> -#include <string/ffs.c>
> -#endif
> diff --git a/sysdeps/i386/math-use-builtins-ffs.h b/sysdeps/i386/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..c0f108c264
> --- /dev/null
> +++ b/sysdeps/i386/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 1
> +#define USE_FFSLL_BUILTIN 0
> diff --git a/sysdeps/ia64/math-use-builtins-ffs.h b/sysdeps/ia64/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..a83bb15414
> --- /dev/null
> +++ b/sysdeps/ia64/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 1
> +#define USE_FFSLL_BUILTIN 1
> diff --git a/sysdeps/m68k/ffs.c b/sysdeps/m68k/ffs.c
> deleted file mode 100644
> index 4415bb0cff..0000000000
> --- a/sysdeps/m68k/ffs.c
> +++ /dev/null
> @@ -1,46 +0,0 @@
> -/* ffs -- find first set bit in a word, counted from least significant end.
> - For mc68020, mc68030, mc68040.
> - This file is part of the GNU C Library.
> - Copyright (C) 1991-2023 Free Software Foundation, Inc.
> -
> - 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/>. */
> -
> -#define ffsl __something_else
> -#include <string.h>
> -
> -#undef ffs
> -
> -#if defined (__GNUC__) && defined (__mc68020__)
> -
> -int
> -__ffs (int x)
> -{
> - int cnt;
> -
> - asm ("bfffo %1{#0:#0},%0" : "=d" (cnt) : "dm" (x & -x));
> -
> - return 32 - cnt;
> -}
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> -#undef ffsl
> -weak_alias (__ffs, ffsl)
> -
> -#else
> -
> -#include <string/ffs.c>
> -
> -#endif
> diff --git a/sysdeps/m68k/math-use-builtins-ffs.h b/sysdeps/m68k/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..4e1d994453
> --- /dev/null
> +++ b/sysdeps/m68k/math-use-builtins-ffs.h
> @@ -0,0 +1,7 @@
> +#if defined __mc68020__ || defined __mc68030__ || defined __mc68040__ \
> + || defined __mc68060__
> +# define USE_FFS_BUILTIN 1
> +#else
> +# define USE_FFS_BUILTIN 0
> +#endif
> +#define USE_FFSLL_BUILTIN 0
> diff --git a/sysdeps/powerpc/ffs.c b/sysdeps/powerpc/ffs.c
> deleted file mode 100644
> index 0a046dab99..0000000000
> --- a/sysdeps/powerpc/ffs.c
> +++ /dev/null
> @@ -1,46 +0,0 @@
> -/* Find first set bit in a word, counted from least significant end.
> - For PowerPC.
> - Copyright (C) 1991-2023 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/>. */
> -
> -#define ffsl __something_else
> -#include <limits.h>
> -#include <string.h>
> -
> -#undef ffs
> -
> -#ifdef __GNUC__
> -
> -int
> -__ffs (int x)
> -{
> - int cnt;
> -
> - asm ("cntlzw %0,%1" : "=r" (cnt) : "r" (x & -x));
> - return 32 - cnt;
> -}
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> -#if ULONG_MAX == UINT_MAX
> -#undef ffsl
> -weak_alias (__ffs, ffsl)
> -#endif
> -
> -#else
> -#include <string/ffs.c>
> -#endif
> diff --git a/sysdeps/powerpc/math-use-builtins-ffs.h b/sysdeps/powerpc/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..7b1d401823
> --- /dev/null
> +++ b/sysdeps/powerpc/math-use-builtins-ffs.h
> @@ -0,0 +1,6 @@
> +#define USE_FFS_BUILTIN 1
> +#ifdef __powerpc64__
> +# define USE_FFSLL_BUILTIN 1
> +#else
> +# define USE_FFSLL_BUILTIN 0
> +#endif
> diff --git a/sysdeps/powerpc/powerpc64/ffsll.c b/sysdeps/powerpc/powerpc64/ffsll.c
> deleted file mode 100644
> index d17cdd1c6b..0000000000
> --- a/sysdeps/powerpc/powerpc64/ffsll.c
> +++ /dev/null
> @@ -1,36 +0,0 @@
> -/* Find first set bit in a word, counted from least significant end.
> - For PowerPC.
> - Copyright (C) 1991-2023 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/>. */
> -
> -#define ffsl __something_else
> -#include <limits.h>
> -#include <string.h>
> -
> -#undef ffs
> -
> -int
> -__ffsll (long long int x)
> -{
> - int cnt;
> -
> - asm ("cntlzd %0,%1" : "=r" (cnt) : "r" (x & -x));
> - return 64 - cnt;
> -}
> -weak_alias (__ffsll, ffsll)
> -#undef ffsl
> -weak_alias (__ffsll, ffsl)
> diff --git a/sysdeps/s390/ffs.c b/sysdeps/s390/ffs.c
> deleted file mode 100644
> index 7627bd3346..0000000000
> --- a/sysdeps/s390/ffs.c
> +++ /dev/null
> @@ -1,69 +0,0 @@
> -/* ffs -- find first set bit in a word, counted from least significant end.
> - S/390 version.
> - Copyright (C) 2000-2023 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 <limits.h>
> -#define ffsl __something_else
> -#include <string.h>
> -
> -#undef ffs
> -
> -/* ffs: find first bit set. This is defined the same way as
> - the libc and compiler builtin ffs routines, therefore
> - differs in spirit from the above ffz (man ffs). */
> -
> -int
> -__ffs (int x)
> -{
> - int r;
> -
> - if (x == 0)
> - return 0;
> - __asm__(" lr %%r1,%1\n"
> - " sr %0,%0\n"
> - " tml %%r1,0xFFFF\n"
> - " jnz 0f\n"
> - " ahi %0,16\n"
> - " srl %%r1,16\n"
> - "0: tml %%r1,0x00FF\n"
> - " jnz 1f\n"
> - " ahi %0,8\n"
> - " srl %%r1,8\n"
> - "1: tml %%r1,0x000F\n"
> - " jnz 2f\n"
> - " ahi %0,4\n"
> - " srl %%r1,4\n"
> - "2: tml %%r1,0x0003\n"
> - " jnz 3f\n"
> - " ahi %0,2\n"
> - " srl %%r1,2\n"
> - "3: tml %%r1,0x0001\n"
> - " jnz 4f\n"
> - " ahi %0,1\n"
> - "4:"
> - : "=&d" (r) : "d" (x) : "cc", "1" );
> - return r+1;
> -}
> -
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> -#if ULONG_MAX == UINT_MAX
> -#undef ffsl
> -weak_alias (__ffs, ffsl)
> -#endif
> diff --git a/sysdeps/x86_64/ffs.c b/sysdeps/x86_64/ffs.c
> deleted file mode 100644
> index a31202969e..0000000000
> --- a/sysdeps/x86_64/ffs.c
> +++ /dev/null
> @@ -1,38 +0,0 @@
> -/* ffs -- find first set bit in a word, counted from least significant end.
> - For AMD x86-64.
> - This file is part of the GNU C Library.
> - Copyright (C) 1991-2023 Free Software Foundation, Inc.
> -
> - 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 <string.h>
> -
> -#undef ffs
> -
> -int
> -__ffs (int x)
> -{
> - int cnt;
> - int tmp;
> -
> - asm ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
> - "cmovel %1,%0\n" /* If number was zero, use -1 as result. */
> - : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
> -
> - return cnt + 1;
> -}
> -weak_alias (__ffs, ffs)
> -libc_hidden_def (__ffs)
> -libc_hidden_builtin_def (ffs)
> diff --git a/sysdeps/x86_64/ffsll.c b/sysdeps/x86_64/ffsll.c
> deleted file mode 100644
> index a1c13d4906..0000000000
> --- a/sysdeps/x86_64/ffsll.c
> +++ /dev/null
> @@ -1,41 +0,0 @@
> -/* ffsll -- find first set bit in a word, counted from least significant end.
> - For AMD x86-64.
> - This file is part of the GNU C Library.
> - Copyright (C) 1991-2023 Free Software Foundation, Inc.
> -
> - 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/>. */
> -
> -#define ffsl __something_else
> -#include <string.h>
> -
> -#undef ffsll
> -
> -int
> -ffsll (long long int x)
> -{
> - long long int cnt;
> - long long int tmp;
> -
> - asm ("bsfq %2,%0\n" /* Count low bits in X and store in %1. */
> - "cmoveq %1,%0\n" /* If number was zero, use -1 as result. */
> - : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
> -
> - return cnt + 1;
> -}
> -
> -#ifndef __ILP32__
> -#undef ffsl
> -weak_alias (ffsll, ffsl)
> -#endif
> diff --git a/sysdeps/x86_64/math-use-builtins-ffs.h b/sysdeps/x86_64/math-use-builtins-ffs.h
> new file mode 100644
> index 0000000000..a83bb15414
> --- /dev/null
> +++ b/sysdeps/x86_64/math-use-builtins-ffs.h
> @@ -0,0 +1,2 @@
> +#define USE_FFS_BUILTIN 1
> +#define USE_FFSLL_BUILTIN 1
> diff --git a/sysdeps/x86_64/x32/ffs.c b/sysdeps/x86_64/x32/ffs.c
> deleted file mode 100644
> index fa7de8b887..0000000000
> --- a/sysdeps/x86_64/x32/ffs.c
> +++ /dev/null
> @@ -1,4 +0,0 @@
> -#define ffsl __something_else
> -#include <sysdeps/x86_64/ffs.c>
> -#undef ffsl
> -weak_alias (__ffs, ffsl)
@@ -18,13 +18,16 @@
#include <limits.h>
#define ffsl __something_else
#include <string.h>
-
#undef ffs
+#include <math-use-builtins.h>
/* Find the first bit set in I. */
int
__ffs (int i)
{
+#if USE_FFS_BUILTIN
+ return __builtin_ffs (i);
+#else
static const unsigned char table[] =
{
0,1,2,2,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,5,
@@ -42,6 +45,7 @@ __ffs (int i)
a = x <= 0xffff ? (x <= 0xff ? 0 : 8) : (x <= 0xffffff ? 16 : 24);
return table[x >> a] + a;
+#endif
}
weak_alias (__ffs, ffs)
libc_hidden_def (__ffs)
@@ -18,20 +18,26 @@
#include <limits.h>
#define ffsl __something_else
#include <string.h>
-
#undef ffsll
+#include <math-use-builtins.h>
+#include <libc-diag.h>
/* Find the first bit set in I. */
int
-ffsll (long long int i)
+__ffsll (long long int i)
{
+#if USE_FFSLL_BUILTIN
+ return __builtin_ffsll (i);
+#else
unsigned long long int x = i & -i;
if (x <= 0xffffffff)
return ffs (i);
else
return 32 + ffs (i >> 32);
+#endif
}
+weak_alias (__ffsll, ffsll)
#if ULONG_MAX != UINT_MAX
#undef ffsl
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 1
+#define USE_FFSLL_BUILTIN 1
deleted file mode 100644
@@ -1,51 +0,0 @@
-/* Copyright (C) 2000-2023 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/>. */
-
-/* Finds the first bit set in an integer. */
-
-#include <sysdep.h>
-
- .arch ev6
- .set noreorder
- .set noat
-
-
-ENTRY(__ffs)
-#ifdef PROF
- ldgp gp, 0(pv)
- lda AT, _mcount
- jsr AT, (AT), _mcount
- .prologue 1
-#else
- .prologue 0
-#endif
-
- zap $16, 0xF0, $16
- cttz $16, $0
- addq $0, 1, $0
- cmoveq $16, 0, $0
-
- nop
- nop
- nop
- ret
-
-END(__ffs)
-
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
deleted file mode 100644
@@ -1,44 +0,0 @@
-/* Copyright (C) 2000-2023 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/>. */
-
-/* Finds the first bit set in a long. */
-
-#include <sysdep.h>
-
- .arch ev6
- .set noreorder
- .set noat
-
-ENTRY(ffsl)
-#ifdef PROF
- ldgp gp, 0(pv)
- lda AT, _mcount
- jsr AT, (AT), _mcount
- .prologue 1
-#else
- .prologue 0
-#endif
-
- cttz $16, $0
- addq $0, 1, $0
- cmoveq $16, 0, $0
- ret
-
-END(ffsl)
-
-weak_extern (ffsl)
-weak_alias (ffsl, ffsll)
deleted file mode 100644
@@ -1,90 +0,0 @@
-/* Copyright (C) 1996-2023 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/>. */
-
-/* Finds the first bit set in an integer. Optimized for the Alpha
- architecture. */
-
-#include <sysdep.h>
-
- .set noreorder
- .set noat
-
-
-ENTRY(__ffs)
-#ifdef PROF
- ldgp gp, 0(pv)
- lda AT, _mcount
- jsr AT, (AT), _mcount
- .prologue 1
- zap $16, 0xF0, $16
- br $ffsl..ng
-#else
- .prologue 0
- zap $16, 0xF0, $16
- # FALLTHRU
-#endif
-END(__ffs)
-
- .align 4
-ENTRY(ffsl)
-#ifdef PROF
- ldgp gp, 0(pv)
- lda AT, _mcount
- jsr AT, (AT), _mcount
- .prologue 1
-$ffsl..ng:
-#else
- .prologue 0
-#endif
- not $16, $1 # e0 :
- ldi $2, -1 # .. e1 :
- cmpbge $1, $2, $3 # e0 : bit N == 1 for byte N == 0
- clr $0 # .. e1 :
- addq $3, 1, $4 # e0 :
- bic $4, $3, $3 # e1 : bit N == 1 for first byte N != 0
- and $3, 0xF0, $4 # e0 :
- and $3, 0xCC, $5 # .. e1 :
- and $3, 0xAA, $6 # e0 :
- cmovne $4, 4, $0 # .. e1 :
- cmovne $5, 2, $5 # e0 :
- cmovne $6, 1, $6 # .. e1 :
- addl $0, $5, $0 # e0 :
- addl $0, $6, $0 # e1 : $0 == N
- extbl $16, $0, $1 # e0 : $1 == byte N
- ldi $2, 1 # .. e1 :
- negq $1, $3 # e0 :
- and $3, $1, $3 # e1 : bit N == least bit set of byte N
- and $3, 0xF0, $4 # e0 :
- and $3, 0xCC, $5 # .. e1 :
- and $3, 0xAA, $6 # e0 :
- cmovne $4, 5, $2 # .. e1 :
- cmovne $5, 2, $5 # e0 :
- cmovne $6, 1, $6 # .. e1 :
- s8addl $0, $2, $0 # e0 : mult byte ofs by 8 and sum
- addl $5, $6, $5 # .. e1 :
- addl $0, $5, $0 # e0 :
- nop # .. e1 :
- cmoveq $16, 0, $0 # e0 : trap input == 0 case.
- ret # .. e1 : 18
-
-END(ffsl)
-
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
-weak_extern (ffsl)
-weak_alias (ffsl, ffsll)
deleted file mode 100644
@@ -1 +0,0 @@
-/* This function is defined in ffs.S. */
new file mode 100644
@@ -0,0 +1,7 @@
+#ifdef __alpha_cix__
+# define USE_FFS_BUILTIN 1
+# define USE_FFSLL_BUILTIN 1
+#else
+# define USE_FFS_BUILTIN 0
+# define USE_FFSLL_BUILTIN 0
+#endif
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 1
+#define USE_FFSLL_BUILTIN 0
deleted file mode 100644
@@ -1,36 +0,0 @@
-/* ffs -- find first set bit in an int, from least significant end.
- Copyright (C) 2013-2023 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 <sysdep.h>
-
- .syntax unified
- .text
-
-ENTRY (__ffs)
- cmp r0, #0
- rbit r0, r0
- itt ne
- clzne r0, r0
- addne r0, r0, #1
- bx lr
-END (__ffs)
-
-weak_alias (__ffs, ffs)
-weak_alias (__ffs, ffsl)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
deleted file mode 100644
@@ -1,50 +0,0 @@
-/* ffsll -- find first set bit in a long long, from least significant end.
- Copyright (C) 2013-2023 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 <sysdep.h>
-
- .syntax unified
- .text
-
-ENTRY (ffsll)
- @ If low part is 0, operate on the high part. Ensure that the
- @ word on which we operate is in r0. Set r2 to the bit offset
- @ of the word being considered. Set the flags for the word
- @ being operated on.
-#ifdef __ARMEL__
- cmp r0, #0
- itee ne
- movne r2, #0
- moveq r2, #32
- movseq r0, r1
-#else
- cmp r1, #0
- ittee ne
- movne r2, #0
- movne r0, r1
- moveq r2, #32
- cmpeq r0, #0
-#endif
- @ Perform the ffs on r0.
- rbit r0, r0
- ittt ne
- clzne r0, r0
- addne r2, r2, #1
- addne r0, r0, r2
- bx lr
-END (ffsll)
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 1
+#define USE_FFSLL_BUILTIN 0
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 0
+#define USE_FFSLL_BUILTIN 0
@@ -40,5 +40,6 @@
#include <math-use-builtins-lrint.h>
#include <math-use-builtins-llrint.h>
#include <math-use-builtins-logb.h>
+#include <math-use-builtins-ffs.h>
#endif /* MATH_USE_BUILTINS_H */
deleted file mode 100644
@@ -1,49 +0,0 @@
-/* ffs -- find first set bit in a word, counted from least significant end.
- For Intel 80x86, x>=3.
- This file is part of the GNU C Library.
- Copyright (C) 1991-2023 Free Software Foundation, Inc.
-
- 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/>. */
-
-#define ffsl __something_else
-#include <string.h>
-
-#undef ffs
-
-#ifdef __GNUC__
-
-int
-__ffs (int x)
-{
- int cnt;
- int tmp;
-
- asm ("xorl %0,%0\n" /* Set CNT to zero. */
- "bsfl %2,%1\n" /* Count low bits in X and store in %1. */
- "jz 1f\n" /* Jump if OK, i.e. X was non-zero. */
- "leal 1(%1),%0\n" /* Return bsfl-result plus one on %0. */
- "1:" : "=&a" (cnt), "=r" (tmp) : "rm" (x));
-
- return cnt;
-}
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
-#undef ffsl
-weak_alias (__ffs, ffsl)
-
-#else
-#include <string/ffs.c>
-#endif
deleted file mode 100644
@@ -1,47 +0,0 @@
-/* ffs -- find first set bit in a word, counted from least significant end.
- For Intel 80x86, x>=6.
- This file is part of the GNU C Library.
- Copyright (C) 1991-2023 Free Software Foundation, Inc.
-
- 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/>. */
-
-#define ffsl __something_else
-#include <string.h>
-
-#undef ffs
-
-#ifdef __GNUC__
-
-int
-__ffs (int x)
-{
- int cnt;
- int tmp;
-
- asm ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
- "cmovel %1,%0\n" /* If number was zero, use -1 as result. */
- : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
-
- return cnt + 1;
-}
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
-#undef ffsl
-weak_alias (__ffs, ffsl)
-
-#else
-#include <string/ffs.c>
-#endif
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 1
+#define USE_FFSLL_BUILTIN 0
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 1
+#define USE_FFSLL_BUILTIN 1
deleted file mode 100644
@@ -1,46 +0,0 @@
-/* ffs -- find first set bit in a word, counted from least significant end.
- For mc68020, mc68030, mc68040.
- This file is part of the GNU C Library.
- Copyright (C) 1991-2023 Free Software Foundation, Inc.
-
- 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/>. */
-
-#define ffsl __something_else
-#include <string.h>
-
-#undef ffs
-
-#if defined (__GNUC__) && defined (__mc68020__)
-
-int
-__ffs (int x)
-{
- int cnt;
-
- asm ("bfffo %1{#0:#0},%0" : "=d" (cnt) : "dm" (x & -x));
-
- return 32 - cnt;
-}
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
-#undef ffsl
-weak_alias (__ffs, ffsl)
-
-#else
-
-#include <string/ffs.c>
-
-#endif
new file mode 100644
@@ -0,0 +1,7 @@
+#if defined __mc68020__ || defined __mc68030__ || defined __mc68040__ \
+ || defined __mc68060__
+# define USE_FFS_BUILTIN 1
+#else
+# define USE_FFS_BUILTIN 0
+#endif
+#define USE_FFSLL_BUILTIN 0
deleted file mode 100644
@@ -1,46 +0,0 @@
-/* Find first set bit in a word, counted from least significant end.
- For PowerPC.
- Copyright (C) 1991-2023 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/>. */
-
-#define ffsl __something_else
-#include <limits.h>
-#include <string.h>
-
-#undef ffs
-
-#ifdef __GNUC__
-
-int
-__ffs (int x)
-{
- int cnt;
-
- asm ("cntlzw %0,%1" : "=r" (cnt) : "r" (x & -x));
- return 32 - cnt;
-}
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
-#if ULONG_MAX == UINT_MAX
-#undef ffsl
-weak_alias (__ffs, ffsl)
-#endif
-
-#else
-#include <string/ffs.c>
-#endif
new file mode 100644
@@ -0,0 +1,6 @@
+#define USE_FFS_BUILTIN 1
+#ifdef __powerpc64__
+# define USE_FFSLL_BUILTIN 1
+#else
+# define USE_FFSLL_BUILTIN 0
+#endif
deleted file mode 100644
@@ -1,36 +0,0 @@
-/* Find first set bit in a word, counted from least significant end.
- For PowerPC.
- Copyright (C) 1991-2023 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/>. */
-
-#define ffsl __something_else
-#include <limits.h>
-#include <string.h>
-
-#undef ffs
-
-int
-__ffsll (long long int x)
-{
- int cnt;
-
- asm ("cntlzd %0,%1" : "=r" (cnt) : "r" (x & -x));
- return 64 - cnt;
-}
-weak_alias (__ffsll, ffsll)
-#undef ffsl
-weak_alias (__ffsll, ffsl)
deleted file mode 100644
@@ -1,69 +0,0 @@
-/* ffs -- find first set bit in a word, counted from least significant end.
- S/390 version.
- Copyright (C) 2000-2023 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 <limits.h>
-#define ffsl __something_else
-#include <string.h>
-
-#undef ffs
-
-/* ffs: find first bit set. This is defined the same way as
- the libc and compiler builtin ffs routines, therefore
- differs in spirit from the above ffz (man ffs). */
-
-int
-__ffs (int x)
-{
- int r;
-
- if (x == 0)
- return 0;
- __asm__(" lr %%r1,%1\n"
- " sr %0,%0\n"
- " tml %%r1,0xFFFF\n"
- " jnz 0f\n"
- " ahi %0,16\n"
- " srl %%r1,16\n"
- "0: tml %%r1,0x00FF\n"
- " jnz 1f\n"
- " ahi %0,8\n"
- " srl %%r1,8\n"
- "1: tml %%r1,0x000F\n"
- " jnz 2f\n"
- " ahi %0,4\n"
- " srl %%r1,4\n"
- "2: tml %%r1,0x0003\n"
- " jnz 3f\n"
- " ahi %0,2\n"
- " srl %%r1,2\n"
- "3: tml %%r1,0x0001\n"
- " jnz 4f\n"
- " ahi %0,1\n"
- "4:"
- : "=&d" (r) : "d" (x) : "cc", "1" );
- return r+1;
-}
-
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
-#if ULONG_MAX == UINT_MAX
-#undef ffsl
-weak_alias (__ffs, ffsl)
-#endif
deleted file mode 100644
@@ -1,38 +0,0 @@
-/* ffs -- find first set bit in a word, counted from least significant end.
- For AMD x86-64.
- This file is part of the GNU C Library.
- Copyright (C) 1991-2023 Free Software Foundation, Inc.
-
- 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 <string.h>
-
-#undef ffs
-
-int
-__ffs (int x)
-{
- int cnt;
- int tmp;
-
- asm ("bsfl %2,%0\n" /* Count low bits in X and store in %1. */
- "cmovel %1,%0\n" /* If number was zero, use -1 as result. */
- : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
-
- return cnt + 1;
-}
-weak_alias (__ffs, ffs)
-libc_hidden_def (__ffs)
-libc_hidden_builtin_def (ffs)
deleted file mode 100644
@@ -1,41 +0,0 @@
-/* ffsll -- find first set bit in a word, counted from least significant end.
- For AMD x86-64.
- This file is part of the GNU C Library.
- Copyright (C) 1991-2023 Free Software Foundation, Inc.
-
- 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/>. */
-
-#define ffsl __something_else
-#include <string.h>
-
-#undef ffsll
-
-int
-ffsll (long long int x)
-{
- long long int cnt;
- long long int tmp;
-
- asm ("bsfq %2,%0\n" /* Count low bits in X and store in %1. */
- "cmoveq %1,%0\n" /* If number was zero, use -1 as result. */
- : "=&r" (cnt), "=r" (tmp) : "rm" (x), "1" (-1));
-
- return cnt + 1;
-}
-
-#ifndef __ILP32__
-#undef ffsl
-weak_alias (ffsll, ffsl)
-#endif
new file mode 100644
@@ -0,0 +1,2 @@
+#define USE_FFS_BUILTIN 1
+#define USE_FFSLL_BUILTIN 1
deleted file mode 100644
@@ -1,4 +0,0 @@
-#define ffsl __something_else
-#include <sysdeps/x86_64/ffs.c>
-#undef ffsl
-weak_alias (__ffs, ffsl)