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e805606193
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14516 Commits

Author SHA1 Message Date
Noah Goldstein
e805606193 x86: Add COND_VZEROUPPER that can replace vzeroupper if no ret 
The RTM vzeroupper mitigation has no way of replacing inline
vzeroupper not before a return.

This can be useful when hoisting a vzeroupper to save code size
for example:

```
L(foo):
	cmpl	%eax, %edx
	jz	L(bar)
	tzcntl	%eax, %eax
	addq	%rdi, %rax
	VZEROUPPER_RETURN

L(bar):
	xorl	%eax, %eax
	VZEROUPPER_RETURN
```

Can become:

```
L(foo):
	COND_VZEROUPPER
	cmpl	%eax, %edx
	jz	L(bar)
	tzcntl	%eax, %eax
	addq	%rdi, %rax
	ret

L(bar):
	xorl	%eax, %eax
	ret
```

This code does not change any existing functionality.

There is no difference in the objdump of libc.so before and after this
patch.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit dd5c483b25)
 2022-07-18 20:45:20 -07:00
Noah Goldstein
70be93d1c5 x86: Create header for VEC classes in x86 strings library 
This patch does not touch any existing code and is only meant to be a
tool for future patches so that simple source files can more easily be
maintained to target multiple VEC classes.

There is no difference in the objdump of libc.so before and after this
patch.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 8a780a6b91)
 2022-07-18 20:45:20 -07:00
Raghuveer Devulapalli
82a707aeb7 x86_64: Add strstr function with 512-bit EVEX 
Adding a 512-bit EVEX version of strstr. The algorithm works as follows:

(1) We spend a few cycles at the begining to peek into the needle. We
locate an edge in the needle (first occurance of 2 consequent distinct
characters) and also store the first 64-bytes into a zmm register.

(2) We search for the edge in the haystack by looking into one cache
line of the haystack at a time. This avoids having to read past a page
boundary which can cause a seg fault.

(3) If an edge is found in the haystack we first compare the first
64-bytes of the needle (already stored in a zmm register) before we
proceed with a full string compare performed byte by byte.

Benchmarking results: (old = strstr_sse2_unaligned, new = strstr_avx512)

Geometric mean of all benchmarks: new / old =  0.66

Difficult skiptable(0) : new / old =  0.02
Difficult skiptable(1) : new / old =  0.01
Difficult 2-way : new / old =  0.25
Difficult testing first 2 : new / old =  1.26
Difficult skiptable(0) : new / old =  0.05
Difficult skiptable(1) : new / old =  0.06
Difficult 2-way : new / old =  0.26
Difficult testing first 2 : new / old =  1.05
Difficult skiptable(0) : new / old =  0.42
Difficult skiptable(1) : new / old =  0.24
Difficult 2-way : new / old =  0.21
Difficult testing first 2 : new / old =  1.04
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 5082a287d5)

x86: Remove __mmask intrinsics in strstr-avx512.c

The intrinsics are not available before GCC7 and using standard
operators generates code of equivalent or better quality.

Removed:
    _cvtmask64_u64
    _kshiftri_mask64
    _kand_mask64

Geometric Mean of 5 Runs of Full Benchmark Suite New / Old: 0.958

(cherry picked from commit f2698954ff)
 2022-07-18 20:45:20 -07:00
H.J. Lu
f6bc52f080 x86-64: Ignore r_addend for R_X86_64_GLOB_DAT/R_X86_64_JUMP_SLOT 
According to x86-64 psABI, r_addend should be ignored for R_X86_64_GLOB_DAT
and R_X86_64_JUMP_SLOT.  Since linkers always set their r_addends to 0, we
can ignore their r_addends.

Reviewed-by: Fangrui Song <maskray@google.com>
(cherry picked from commit f8587a6189)
 2022-07-18 20:45:20 -07:00
Sunil K Pandey
8ab861d295 x86_64: Implement evex512 version of strlen, strnlen, wcslen and wcsnlen 
This patch implements following evex512 version of string functions.
Perf gain for evex512 version is up to 50% as compared to evex,
depending on length and alignment.

Placeholder function, not used by any processor at the moment.

- String length function using 512 bit vectors.
- String N length using 512 bit vectors.
- Wide string length using 512 bit vectors.
- Wide string N length using 512 bit vectors.

Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
(cherry picked from commit 9c66efb86f)
 2022-07-18 20:45:20 -07:00
Adhemerval Zanella
eb9aa96fac x86_64: Remove bzero optimization 
Both symbols are marked as legacy in POSIX.1-2001 and removed on
POSIX.1-2008, although the prototypes are defined for _GNU_SOURCE
or _DEFAULT_SOURCE.

GCC also replaces bcopy with a memmove and bzero with memset on default
configuration (to actually get a bzero libc call the code requires
to omit string.h inclusion and built with -fno-builtin), so it is
highly unlikely programs are actually calling libc bzero symbol.

On a recent Linux distro (Ubuntu 22.04), there is no bzero calls
by the installed binaries.

  $ cat count_bstring.sh
  #!/bin/bash

  files=`IFS=':';for i in $PATH; do test -d "$i" && find "$i" -maxdepth 1 -executable -type f; done`
  total=0
  for file in $files; do
    symbols=`objdump -R $file 2>&1`
    if [ $? -eq 0 ]; then
      ncalls=`echo $symbols | grep -w $1 | wc -l`
      ((total=total+ncalls))
      if [ $ncalls -gt 0 ]; then
        echo "$file: $ncalls"
      fi
    fi
  done
  echo "TOTAL=$total"
  $ ./count_bstring.sh bzero
  TOTAL=0

Checked on x86_64-linux-gnu.

(cherry picked from commit 9403b71ae9)
 2022-07-18 20:45:20 -07:00
Sunil K Pandey
8d324019e6 x86_64: Remove end of line trailing spaces 
This commit remove trailing space introduced by following commit.

commit a775a7a3eb
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date:   Wed Jun 23 01:56:29 2021 -0400

    x86: Fix overflow bug in wcsnlen-sse4_1 and wcsnlen-avx2 [BZ #27974]
 2022-07-18 20:45:09 -07:00
Adhemerval Zanella
4b246b2bbd linux: Fix mq_timereceive check for 32 bit fallback code (BZ 29304) 
On  success,  mq_receive() and mq_timedreceive() return the number of
bytes in the received message, so it requires to check if the value
is larger than 0.

Checked on i686-linux-gnu.

(cherry picked from commit 71d87d85bf)
 2022-06-30 10:46:39 -03:00
Adhemerval Zanella
bb4148283f nios2: Remove _dl_skip_args usage (BZ# 29187) 
Since ad43cac44a the generic code already shuffles the argv/envp/auxv
on the stack to remove the ld.so own arguments and thus _dl_skip_args
is always 0.   So there is no need to adjust the argc or argv.

Checked with qemu-user that arguments are correctly passed on both
constructors and main program.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 4868ba5d25)
 2022-06-10 09:15:00 -03:00
Adhemerval Zanella
96944f0f81 hppa: Remove _dl_skip_args usage (BZ# 29165) 
Different than other architectures, hppa creates an unrelated stack
frame where ld.so argc/argv adjustments done by ad43cac44a
is not done on the argc/argv saved/restore by _dl_start_user.

Instead load _dl_argc and _dl_argv directlty instead of adjust them
using _dl_skip_args value.

Checked on hppa-linux-gnu.

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
(cherry picked from commit 6242602273)
 2022-06-10 09:13:54 -03:00
Adhemerval Zanella
a7ec6363a3 nptl: Fix __libc_cleanup_pop_restore asynchronous restore (BZ#29214) 
This was due a wrong revert done on 404656009b.

Checked on x86_64-linux-gnu.

(cherry picked from commit c7d36dcecc)
 2022-06-08 17:15:08 -03:00
Matheus Castanho
4c92a10412 powerpc: Fix VSX register number on __strncpy_power9 [BZ #29197] 
__strncpy_power9 initializes VR 18 with zeroes to be used throughout the
code, including when zero-padding the destination string. However, the
v18 reference was mistakenly being used for stxv and stxvl, which take a
VSX vector as operand. The code ended up using the uninitialized VSR 18
register by mistake.

Both occurrences have been changed to use the proper VSX number for VR 18
(i.e. VSR 50).

Tested on powerpc, powerpc64 and powerpc64le.

Signed-off-by: Kewen Lin <linkw@gcc.gnu.org>
(cherry picked from commit 0218463dd8)
 2022-06-07 15:34:20 -03:00
Adhemerval Zanella
61fd3e0e74 socket: Use 64 bit stat for isfdtype (BZ# 29209) 
This is a missing spot initially from 52a5fe70a2.

Checked on i686-linux-gnu.

(cherry picked from commit 87f1ec12e7)
 2022-06-01 13:34:51 -03:00
Adhemerval Zanella
f9c3e57ac2 posix: Use 64 bit stat for fpathconf (_PC_ASYNC_IO) (BZ# 29208) 
This is a missing spot initially from 52a5fe70a2.

Checked on i686-linux-gnu.

(cherry picked from commit 6e7137f28c)
 2022-06-01 13:34:51 -03:00
Adhemerval Zanella
9db6a597ef posix: Use 64 bit stat for posix_fallocate fallback (BZ# 29207) 
This is a missing spot initially from 52a5fe70a2.

Checked on i686-linux-gnu.

(cherry picked from commit 574ba60fc8)
 2022-06-01 13:34:51 -03:00
Arjun Shankar
ff450cdbde Fix deadlock when pthread_atfork handler calls pthread_atfork or dlclose 
In multi-threaded programs, registering via pthread_atfork,
de-registering implicitly via dlclose, or running pthread_atfork
handlers during fork was protected by an internal lock.  This meant
that a pthread_atfork handler attempting to register another handler or
dlclose a dynamically loaded library would lead to a deadlock.

This commit fixes the deadlock in the following way:

During the execution of handlers at fork time, the atfork lock is
released prior to the execution of each handler and taken again upon its
return.  Any handler registrations or de-registrations that occurred
during the execution of the handler are accounted for before proceeding
with further handler execution.

If a handler that hasn't been executed yet gets de-registered by another
handler during fork, it will not be executed.   If a handler gets
registered by another handler during fork, it will not be executed
during that particular fork.

The possibility that handlers may now be registered or deregistered
during handler execution means that identifying the next handler to be
run after a given handler may register/de-register others requires some
bookkeeping.  The fork_handler struct has an additional field, 'id',
which is assigned sequentially during registration.  Thus, handlers are
executed in ascending order of 'id' during 'prepare', and descending
order of 'id' during parent/child handler execution after the fork.

Two tests are included:

* tst-atfork3: Adhemerval Zanella <adhemerval.zanella@linaro.org>
  This test exercises calling dlclose from prepare, parent, and child
  handlers.

* tst-atfork4: This test exercises calling pthread_atfork and dlclose
  from the prepare handler.

[BZ #24595, BZ #27054]

Co-authored-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit 52a103e237)
 2022-05-30 12:38:32 +02:00
Noah Goldstein
83ae8287c1 x86: Fallback {str|wcs}cmp RTM in the ncmp overflow case [BZ #29127] 
Re-cherry-pick commit c627209832 for strcmp-avx2.S change which was
omitted in intial cherry pick because at the time this bug was not
present on release branch.

Fixes BZ #29127.

In the overflow fallback strncmp-avx2-rtm and wcsncmp-avx2-rtm would
call strcmp-avx2 and wcscmp-avx2 respectively. This would have
not checks around vzeroupper and would trigger spurious
aborts. This commit fixes that.

test-strcmp, test-strncmp, test-wcscmp, and test-wcsncmp all pass on
AVX2 machines with and without RTM.

Co-authored-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit c627209832)
 2022-05-25 15:05:05 -07:00
Szabolcs Nagy
b2585cae28 linux: Add a getauxval test [BZ #23293] 
This is for bug 23293 and it relies on the glibc test system running
tests via explicit ld.so invokation by default.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
(cherry picked from commit 9faf5262c7)
 2022-05-19 16:48:47 +01:00
Szabolcs Nagy
c73c79af7d rtld: Use generic argv adjustment in ld.so [BZ #23293] 
When an executable is invoked as

  ./ld.so [ld.so-args] ./exe [exe-args]

then the argv is adujusted in ld.so before calling the entry point of
the executable so ld.so args are not visible to it.  On most targets
this requires moving argv, env and auxv on the stack to ensure correct
stack alignment at the entry point.  This had several issues:

- The code for this adjustment on the stack is written in asm as part
  of the target specific ld.so _start code which is hard to maintain.

- The adjustment is done after _dl_start returns, where it's too late
  to update GLRO(dl_auxv), as it is already readonly, so it points to
  memory that was clobbered by the adjustment. This is bug 23293.

- _environ is also wrong in ld.so after the adjustment, but it is
  likely not used after _dl_start returns so this is not user visible.

- _dl_argv was updated, but for this it was moved out of relro, which
  changes security properties across targets unnecessarily.

This patch introduces a generic _dl_start_args_adjust function that
handles the argument adjustments after ld.so processed its own args
and before relro protection is applied.

The same algorithm is used on all targets, _dl_skip_args is now 0, so
existing target specific adjustment code is no longer used.  The bug
affects aarch64, alpha, arc, arm, csky, ia64, nios2, s390-32 and sparc,
other targets don't need the change in principle, only for consistency.

The GNU Hurd start code relied on _dl_skip_args after dl_main returned,
now it checks directly if args were adjusted and fixes the Hurd startup
data accordingly.

Follow up patches can remove _dl_skip_args and DL_ARGV_NOT_RELRO.

Tested on aarch64-linux-gnu and cross tested on i686-gnu.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit ad43cac44a)
 2022-05-19 16:48:47 +01:00
Stefan Liebler
89b638f48a S390: Enable static PIE 
This commit enables static PIE on 64bit.  On 31bit, static PIE is
not supported.

A new configure check in sysdeps/s390/s390-64/configure.ac also performs
a minimal test for requirements in ld:
Ensure you also have those patches for:
- binutils (ld)
  - "[PR ld/22263] s390: Avoid dynamic TLS relocs in PIE"
    https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=26b1426577b5dcb32d149c64cca3e603b81948a9
    (Tested by configure check above)
    Otherwise there will be a R_390_TLS_TPOFF relocation, which fails to
    be processed in _dl_relocate_static_pie() as static TLS map is not setup.
  - "s390: Add DT_JMPREL pointing to .rela.[i]plt with static-pie"
    https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=d942d8db12adf4c9e5c7d9ed6496a779ece7149e
    (We can't test it in configure as we are not able to link a static PIE
    executable if the system glibc lacks static PIE support)
    Otherwise there won't be DT_JMPREL, DT_PLTRELA, DT_PLTRELASZ entries
    and the IFUNC symbols are not processed, which leads to crashes.

- kernel (the mentioned links to the commits belong to 5.19 merge window):
  - "s390/mmap: increase stack/mmap gap to 128MB"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=f2f47d0ef72c30622e62471903ea19446ea79ee2
  - "s390/vdso: move vdso mapping to its own function"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=57761da4dc5cd60bed2c81ba0edb7495c3c740b8
  - "s390/vdso: map vdso above stack"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=9e37a2e8546f9e48ea76c839116fa5174d14e033
  - "s390/vdso: add vdso randomization"
    https://git.kernel.org/pub/scm/linux/kernel/git/s390/linux.git/commit/?h=features&id=41cd81abafdc4e58a93fcb677712a76885e3ca25
  (We can't test the kernel of the target system)
  Otherwise if /proc/sys/kernel/randomize_va_space is turned off (0),
  static PIE executables like ldconfig will crash.  While startup sbrk is
  used to enlarge the HEAP.  Unfortunately the underlying brk syscall fails
  as there is not enough space after the HEAP.  Then the address of the TLS
  image is invalid and the following memcpy in __libc_setup_tls() leads
  to a segfault.
  If /proc/sys/kernel/randomize_va_space is activated (default: 2), there
  is enough space after HEAP.

- glibc
  - "Linux: Define MMAP_CALL_INTERNAL"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=c1b68685d438373efe64e5f076f4215723004dfb
  - "i386: Remove OPTIMIZE_FOR_GCC_5 from Linux libc-do-syscall.S"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=6e5c7a1e262961adb52443ab91bd2c9b72316402
  - "i386: Honor I386_USE_SYSENTER for 6-argument Linux system calls"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=60f0f2130d30cfd008ca39743027f1e200592dff
  - "ia64: Always define IA64_USE_NEW_STUB as a flag macro"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=18bd9c3d3b1b6a9182698c85354578d1d58e9d64
  - "Linux: Implement a useful version of _startup_fatal"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=a2a6bce7d7e52c1c34369a7da62c501cc350bc31
  - "Linux: Introduce __brk_call for invoking the brk system call"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=b57ab258c1140bc45464b4b9908713e3e0ee35aa
  - "csu: Implement and use _dl_early_allocate during static startup"
    https://sourceware.org/git/?p=glibc.git;a=commit;h=f787e138aa0bf677bf74fa2a08595c446292f3d7
  The mentioned patch series by Florian Weimer avoids the mentioned failing
  sbrk syscall by falling back to mmap.

This commit also adjusts startup code in start.S to be ready for static PIE.
We have to add a wrapper function for main as we are not allowed to use
GOT relocations before __libc_start_main is called.
(Compare also to:
- commit 14d886edbd
  "aarch64: fix start code for static pie"
- commit 3d1d79283e
  "aarch64: fix static pie enabled libc when main is in a shared library"
)

(cherry picked from commit 728894dba4)
 2022-05-19 17:15:57 +02:00
Florian Weimer
ede8d94d15 csu: Implement and use _dl_early_allocate during static startup 
This implements mmap fallback for a brk failure during TLS
allocation.

scripts/tls-elf-edit.py is updated to support the new patching method.
The script no longer requires that in the input object is of ET_DYN
type.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit f787e138aa)
 2022-05-19 12:13:53 +02:00
Florian Weimer
43d77ef9b8 Linux: Introduce __brk_call for invoking the brk system call 
Alpha and sparc can now use the generic implementation.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit b57ab258c1)
 2022-05-19 12:13:53 +02:00
Florian Weimer
e7ca2a475c Linux: Implement a useful version of _startup_fatal 
On i386 and ia64, the TCB is not available at this point.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit a2a6bce7d7)
 2022-05-19 12:13:53 +02:00
Florian Weimer
b2387bea84 ia64: Always define IA64_USE_NEW_STUB as a flag macro 
And keep the previous definition if it exists.  This allows
disabling IA64_USE_NEW_STUB while keeping USE_DL_SYSINFO defined.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit 18bd9c3d3b)
 2022-05-19 12:13:53 +02:00
Florian Weimer
b38c9cdb58 Linux: Define MMAP_CALL_INTERNAL 
Unlike MMAP_CALL, this avoids a TCB dependency for an errno update
on failure.

<mmap_internal.h> cannot be included as is on several architectures
due to the definition of page_unit, so introduce a separate header
file for the definition of MMAP_CALL and MMAP_CALL_INTERNAL,
<mmap_call.h>.

Reviewed-by: Stefan Liebler <stli@linux.ibm.com>
(cherry picked from commit c1b68685d4)
 2022-05-19 12:13:53 +02:00
Florian Weimer
1a5b9d1a23 i386: Honor I386_USE_SYSENTER for 6-argument Linux system calls 
Introduce an int-80h-based version of __libc_do_syscall and use
it if I386_USE_SYSENTER is defined as 0.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 60f0f2130d)
 2022-05-19 12:13:53 +02:00
Florian Weimer
1e7b011f87 i386: Remove OPTIMIZE_FOR_GCC_5 from Linux libc-do-syscall.S 
After commit a78e6a10d0
("i386: Remove broken CAN_USE_REGISTER_ASM_EBP (bug 28771)"),
it is never defined.

Reviewed-by: H.J. Lu <hjl.tools@gmail.com>
(cherry picked from commit 6e5c7a1e26)
 2022-05-19 12:13:53 +02:00
Fangrui Song
be9240c84c elf: Remove __libc_init_secure 
After 73fc4e28b9,
__libc_enable_secure_decided is always 0 and a statically linked
executable may overwrite __libc_enable_secure without considering
AT_SECURE.

The __libc_enable_secure has been correctly initialized in _dl_aux_init,
so just remove __libc_enable_secure_decided and __libc_init_secure.
This allows us to remove some startup_get*id functions from
22b79ed7f4.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
(cherry picked from commit 3e9acce8c5)
 2022-05-19 12:13:52 +02:00
Florian Weimer
ff900fad89 Linux: Consolidate auxiliary vector parsing (redo) 
And optimize it slightly.

This is commit 8c8510ab27 revised.

In _dl_aux_init in elf/dl-support.c, use an explicit loop
and -fno-tree-loop-distribute-patterns to avoid memset.

Reviewed-by: Szabolcs Nagy <szabolcs.nagy@arm.com>
(cherry picked from commit 73fc4e28b9)
 2022-05-19 12:13:51 +02:00
Florian Weimer
28bdb03b1b Linux: Include <dl-auxv.h> in dl-sysdep.c only for SHARED 
Otherwise, <dl-auxv.h> on POWER ends up being included twice,
once in dl-sysdep.c, once in dl-support.c.  That leads to a linker
failure due to multiple definitions of _dl_cache_line_size.

Fixes commit d96d2995c1
("Revert "Linux: Consolidate auxiliary vector parsing").

(cherry picked from commit 098c795e85)
 2022-05-19 11:49:06 +02:00
Florian Weimer
1cc4ddfeeb Revert "Linux: Consolidate auxiliary vector parsing" 
This reverts commit 8c8510ab27.  The
revert is not perfect because the commit included a bug fix for
_dl_sysdep_start with an empty argv, introduced in commit
2d47fa6862 ("Linux: Remove
DL_FIND_ARG_COMPONENTS"), and this bug fix is kept.

The revert is necessary because the reverted commit introduced an
early memset call on aarch64, which leads to crash due to lack of TCB
initialization.

(cherry picked from commit d96d2995c1)
 2022-05-19 11:49:06 +02:00
Florian Weimer
4b9cd5465d Linux: Consolidate auxiliary vector parsing 
And optimize it slightly.

The large switch statement in _dl_sysdep_start can be replaced with
a large array.  This reduces source code and binary size.  On
i686-linux-gnu:

Before:

   text	   data	    bss	    dec	    hex	filename
   7791	     12	      0	   7803	   1e7b	elf/dl-sysdep.os

After:

   text	   data	    bss	    dec	    hex	filename
   7135	     12	      0	   7147	   1beb	elf/dl-sysdep.os

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit 8c8510ab27)
 2022-05-19 11:49:06 +02:00
Florian Weimer
08728256fa Linux: Assume that NEED_DL_SYSINFO_DSO is always defined 
The definition itself is still needed for generic code.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit f19fc997a5)
 2022-05-19 11:49:06 +02:00
Florian Weimer
458733fffe Linux: Remove DL_FIND_ARG_COMPONENTS 
The generic definition is always used since the Native Client
port has been removed.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit 2d47fa6862)
 2022-05-19 11:49:06 +02:00
Florian Weimer
2139b1848e Linux: Remove HAVE_AUX_SECURE, HAVE_AUX_XID, HAVE_AUX_PAGESIZE 
They are always defined.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit b9c3d3382f)
 2022-05-19 11:49:06 +02:00
Florian Weimer
b0bd6a1323 elf: Merge dl-sysdep.c into the Linux version 
The generic version is the de-facto Linux implementation.  It
requires an auxiliary vector, so Hurd does not use it.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>
(cherry picked from commit 91c0a47ffb)
 2022-05-19 11:43:53 +02:00
Noah Goldstein
596c9a32cc x86: Optimize {str|wcs}rchr-evex 
The new code unrolls the main loop slightly without adding too much
overhead and minimizes the comparisons for the search CHAR.

Geometric Mean of all benchmarks New / Old: 0.755
See email for all results.

Full xcheck passes on x86_64 with and without multiarch enabled.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit c966099cdc)
 2022-05-16 18:55:54 -07:00
Noah Goldstein
00f09a14d2 x86: Optimize {str|wcs}rchr-avx2 
The new code unrolls the main loop slightly without adding too much
overhead and minimizes the comparisons for the search CHAR.

Geometric Mean of all benchmarks New / Old: 0.832
See email for all results.

Full xcheck passes on x86_64 with and without multiarch enabled.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit df7e295d18)
 2022-05-16 18:55:45 -07:00
Noah Goldstein
0a11305416 x86: Optimize {str|wcs}rchr-sse2 
The new code unrolls the main loop slightly without adding too much
overhead and minimizes the comparisons for the search CHAR.

Geometric Mean of all benchmarks New / Old: 0.741
See email for all results.

Full xcheck passes on x86_64 with and without multiarch enabled.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 5307aa9c18)
 2022-05-16 18:55:37 -07:00
Noah Goldstein
df5de87260 x86: Cleanup page cross code in memcmp-avx2-movbe.S 
Old code was both inefficient and wasted code size. New code (-62
bytes) and comparable or better performance in the page cross case.

geometric_mean(N=20) of page cross cases New / Original: 0.960

size, align0, align1, ret, New Time/Old Time
   1,   4095,      0,   0,             1.001
   1,   4095,      0,   1,             0.999
   1,   4095,      0,  -1,               1.0
   2,   4094,      0,   0,               1.0
   2,   4094,      0,   1,               1.0
   2,   4094,      0,  -1,               1.0
   3,   4093,      0,   0,               1.0
   3,   4093,      0,   1,               1.0
   3,   4093,      0,  -1,               1.0
   4,   4092,      0,   0,             0.987
   4,   4092,      0,   1,               1.0
   4,   4092,      0,  -1,               1.0
   5,   4091,      0,   0,             0.984
   5,   4091,      0,   1,             1.002
   5,   4091,      0,  -1,             1.005
   6,   4090,      0,   0,             0.993
   6,   4090,      0,   1,             1.001
   6,   4090,      0,  -1,             1.003
   7,   4089,      0,   0,             0.991
   7,   4089,      0,   1,               1.0
   7,   4089,      0,  -1,             1.001
   8,   4088,      0,   0,             0.875
   8,   4088,      0,   1,             0.881
   8,   4088,      0,  -1,             0.888
   9,   4087,      0,   0,             0.872
   9,   4087,      0,   1,             0.879
   9,   4087,      0,  -1,             0.883
  10,   4086,      0,   0,             0.878
  10,   4086,      0,   1,             0.886
  10,   4086,      0,  -1,             0.873
  11,   4085,      0,   0,             0.878
  11,   4085,      0,   1,             0.881
  11,   4085,      0,  -1,             0.879
  12,   4084,      0,   0,             0.873
  12,   4084,      0,   1,             0.889
  12,   4084,      0,  -1,             0.875
  13,   4083,      0,   0,             0.873
  13,   4083,      0,   1,             0.863
  13,   4083,      0,  -1,             0.863
  14,   4082,      0,   0,             0.838
  14,   4082,      0,   1,             0.869
  14,   4082,      0,  -1,             0.877
  15,   4081,      0,   0,             0.841
  15,   4081,      0,   1,             0.869
  15,   4081,      0,  -1,             0.876
  16,   4080,      0,   0,             0.988
  16,   4080,      0,   1,              0.99
  16,   4080,      0,  -1,             0.989
  17,   4079,      0,   0,             0.978
  17,   4079,      0,   1,             0.981
  17,   4079,      0,  -1,              0.98
  18,   4078,      0,   0,             0.981
  18,   4078,      0,   1,              0.98
  18,   4078,      0,  -1,             0.985
  19,   4077,      0,   0,             0.977
  19,   4077,      0,   1,             0.979
  19,   4077,      0,  -1,             0.986
  20,   4076,      0,   0,             0.977
  20,   4076,      0,   1,             0.986
  20,   4076,      0,  -1,             0.984
  21,   4075,      0,   0,             0.977
  21,   4075,      0,   1,             0.983
  21,   4075,      0,  -1,             0.988
  22,   4074,      0,   0,             0.983
  22,   4074,      0,   1,             0.994
  22,   4074,      0,  -1,             0.993
  23,   4073,      0,   0,              0.98
  23,   4073,      0,   1,             0.992
  23,   4073,      0,  -1,             0.995
  24,   4072,      0,   0,             0.989
  24,   4072,      0,   1,             0.989
  24,   4072,      0,  -1,             0.991
  25,   4071,      0,   0,              0.99
  25,   4071,      0,   1,             0.999
  25,   4071,      0,  -1,             0.996
  26,   4070,      0,   0,             0.993
  26,   4070,      0,   1,             0.995
  26,   4070,      0,  -1,             0.998
  27,   4069,      0,   0,             0.993
  27,   4069,      0,   1,             0.999
  27,   4069,      0,  -1,               1.0
  28,   4068,      0,   0,             0.997
  28,   4068,      0,   1,               1.0
  28,   4068,      0,  -1,             0.999
  29,   4067,      0,   0,             0.996
  29,   4067,      0,   1,             0.999
  29,   4067,      0,  -1,             0.999
  30,   4066,      0,   0,             0.991
  30,   4066,      0,   1,             1.001
  30,   4066,      0,  -1,             0.999
  31,   4065,      0,   0,             0.988
  31,   4065,      0,   1,             0.998
  31,   4065,      0,  -1,             0.998
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 23102686ec)
 2022-05-16 18:55:24 -07:00
Noah Goldstein
ffe75982cc x86: Remove memcmp-sse4.S 
Code didn't actually use any sse4 instructions since `ptest` was
removed in:

commit 2f9062d717
Author: Noah Goldstein <goldstein.w.n@gmail.com>
Date:   Wed Nov 10 16:18:56 2021 -0600

    x86: Shrink memcmp-sse4.S code size

The new memcmp-sse2 implementation is also faster.

geometric_mean(N=20) of page cross cases SSE2 / SSE4: 0.905

Note there are two regressions preferring SSE2 for Size = 1 and Size =
65.

Size = 1:
size, align0, align1, ret, New Time/Old Time
   1,      1,      1,   0,               1.2
   1,      1,      1,   1,             1.197
   1,      1,      1,  -1,               1.2

This is intentional. Size == 1 is significantly less hot based on
profiles of GCC11 and Python3 than sizes [4, 8] (which is made
hotter).

Python3 Size = 1        -> 13.64%
Python3 Size = [4, 8]   -> 60.92%

GCC11   Size = 1        ->  1.29%
GCC11   Size = [4, 8]   -> 33.86%

size, align0, align1, ret, New Time/Old Time
   4,      4,      4,   0,             0.622
   4,      4,      4,   1,             0.797
   4,      4,      4,  -1,             0.805
   5,      5,      5,   0,             0.623
   5,      5,      5,   1,             0.777
   5,      5,      5,  -1,             0.802
   6,      6,      6,   0,             0.625
   6,      6,      6,   1,             0.813
   6,      6,      6,  -1,             0.788
   7,      7,      7,   0,             0.625
   7,      7,      7,   1,             0.799
   7,      7,      7,  -1,             0.795
   8,      8,      8,   0,             0.625
   8,      8,      8,   1,             0.848
   8,      8,      8,  -1,             0.914
   9,      9,      9,   0,             0.625

Size = 65:
size, align0, align1, ret, New Time/Old Time
  65,      0,      0,   0,             1.103
  65,      0,      0,   1,             1.216
  65,      0,      0,  -1,             1.227
  65,     65,      0,   0,             1.091
  65,      0,     65,   1,              1.19
  65,     65,     65,  -1,             1.215

This is because A) the checks in range [65, 96] are now unrolled 2x
and B) because smaller values <= 16 are now given a hotter path. By
contrast the SSE4 version has a branch for Size = 80. The unrolled
version has get better performance for returns which need both
comparisons.

size, align0, align1, ret, New Time/Old Time
 128,      4,      8,   0,             0.858
 128,      4,      8,   1,             0.879
 128,      4,      8,  -1,             0.888

As well, out of microbenchmark environments that are not full
predictable the branch will have a real-cost.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 7cbc03d030)
 2022-05-16 18:55:16 -07:00
Noah Goldstein
4ff6ae069b x86: Small improvements for wcslen 
Just a few QOL changes.
    1. Prefer `add` > `lea` as it has high execution units it can run
       on.
    2. Don't break macro-fusion between `test` and `jcc`
    3. Reduce code size by removing gratuitous padding bytes (-90
       bytes).

geometric_mean(N=20) of all benchmarks New / Original: 0.959

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 244b415d38)
 2022-05-16 18:55:09 -07:00
Noah Goldstein
80883f4354 x86: Remove AVX str{n}casecmp 
The rational is:

1. SSE42 has nearly identical logic so any benefit is minimal (3.4%
   regression on Tigerlake using SSE42 versus AVX across the
   benchtest suite).
2. AVX2 version covers the majority of targets that previously
   prefered it.
3. The targets where AVX would still be best (SnB and IVB) are
   becoming outdated.

All in all the saving the code size is worth it.

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 305769b2a1)
 2022-05-16 18:55:02 -07:00
Noah Goldstein
b13a2e68eb x86: Add EVEX optimized str{n}casecmp 
geometric_mean(N=40) of all benchmarks EVEX / SSE42: .621

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 84e7c46df4)
 2022-05-16 18:54:52 -07:00
Noah Goldstein
3051cf3e74 x86: Add AVX2 optimized str{n}casecmp 
geometric_mean(N=40) of all benchmarks AVX2 / SSE42: .702

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit bbf8122234)
 2022-05-16 18:54:41 -07:00
Noah Goldstein
3605c74407 x86: Optimize str{n}casecmp TOLOWER logic in strcmp-sse42.S 
Slightly faster method of doing TOLOWER that saves an
instruction.

Also replace the hard coded 5-byte no with .p2align 4. On builds with
CET enabled this misaligned entry to strcasecmp.

geometric_mean(N=40) of all benchmarks New / Original: .920

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit d154758e61)
 2022-05-16 18:54:27 -07:00
Noah Goldstein
5997011826 x86: Optimize str{n}casecmp TOLOWER logic in strcmp.S 
Slightly faster method of doing TOLOWER that saves an
instruction.

Also replace the hard coded 5-byte no with .p2align 4. On builds with
CET enabled this misaligned entry to strcasecmp.

geometric_mean(N=40) of all benchmarks New / Original: .894

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 670b54bc58)
 2022-05-16 18:54:17 -07:00
Noah Goldstein
a4b1cae068 x86: Remove strspn-sse2.S and use the generic implementation 
The generic implementation is faster.

geometric_mean(N=20) of all benchmarks New / Original: .710

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 9c8a6ad620)
 2022-05-16 18:54:09 -07:00
Noah Goldstein
3811544655 x86: Remove strpbrk-sse2.S and use the generic implementation 
The generic implementation is faster (see strcspn commit).

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit 6533585352)
 2022-05-16 18:53:59 -07:00
Noah Goldstein
0dafa75e3c x86: Remove strcspn-sse2.S and use the generic implementation 
The generic implementation is faster.

geometric_mean(N=20) of all benchmarks New / Original: .678

All string/memory tests pass.
Reviewed-by: H.J. Lu <hjl.tools@gmail.com>

(cherry picked from commit fe28e7d9d9)
 2022-05-16 18:53:48 -07:00