Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
This patch enables PACBTI for all relevant variants of strlen:
* Newlib for armv8.1-m.main+pacbti
* Newlib for armv8.1-m.main+pacbti+mve
* Newlib-nano
Add function prologue/epilogue to conditionally add BTI landing pads
and/or PAC code generation & authentication instructions depending on
compilation flags.
This patch enables PACBTI for all relevant variants of strcmp:
* Newlib for armv8.1-m.main+pacbti
* Newlib for armv8.1-m.main+pacbti+mve
* Newlib-nano
Augment the arm_asm.h header file to simplify function prologues and
epilogues whilst adding support for PACBTI enablement via macros for
hand-written assembly functions. For PACBTI, both prologues/epilogues
as well as cfi-related directives are automatically amended
accordingly, depending on the compile-time mbranch-protection argument
values.
It defines the following preprocessor macros:
* HAVE_PAC_LEAF: Indicates whether pac-signing has been requested for
leaf functions.
* PAC_LEAF_PUSH_IP: Whether leaf functions should push the pac code
to the stack irrespective of whether the ip register is clobbered in
the function or not.
* STACK_ALIGN_ENFORCE: Whether a dummy register should be added to
the push list as necessary in the prologue to ensure stack
alignment preservation at the start of assembly function. The
epilogue behavior is likewise affected by this flag, ensuring any
pushed dummy registers also get popped on function return.
It also defines the following assembler macros:
* prologue: In addition to pushing any callee-saved registers onto
the stack, it generates any requested pacbti instructions.
Pushed registers are specified via the optional `first', `last',
`push_ip' and `push_lr' macro argument parameters.
when a single register number is provided, it pushes that
register. When two register numbers are provided, they specify a
rage to save. If push_ip and/or push_lr are non-zero, the
respective registers are also saved. Stack alignment is requested
via the `align` argument, which defaults to the value of
STACK_ALIGN_ENFORCE, unless manually overridden.
For example:
prologue push_ip=1 -> push {ip}
prologue push_ip=1, align8=1 -> push {r2, ip}
prologue push_ip=1, push_lr=1 -> push {ip, lr}
prologue 1 -> push {r1}
prologue 1, align8=1 -> push {r0, r1}
prologue 1 push_ip=1 -> push {r1, ip}
prologue 1 4 -> push {r1-r4}
prologue 1 4 push_ip=1 -> push {r1-r4, ip}
* epilogue: pops registers off the stack and emits pac key signing
instruction, if requested. The `first', `last', `push_ip',
`push_lr' and `align' function as per the prologue macro,
generating pop instead of push instructions.
Stack alignment is enforced via the following helper macro
call-chain:
{prologue|epilogue} ->_align8 -> _preprocess_reglist ->
_preprocess_reglist1 -> {_prologue|_epilogue}
Finally, the necessary cfi directives for adding debug information
to prologue and epilogue are generated via the following macros:
* cfisavelist - prologue macro helper function, generating
necessary .cfi_offset directives associated with push instruction.
Therefore, the net effect of calling `prologue 1 2 push_ip=1' is
to generate the following:
push {r1-r2, ip}
.cfi_adjust_cfa_offset 12
.cfi_offset 143, -4
.cfi_offset 2, -8
.cfi_offset 1, -12
* cfirestorelist - epilogue macro helper function, emitting
.cfi_restore instructions prior to resetting the cfa offset. As
such, calling `epilogue 1 2 push_ip=1' will produce:
pop {r1-r2, ip}
.cfi_register 143, 12
.cfi_restore 2
.cfi_restore 1
.cfi_def_cfa_offset 0
_pinfo::ctty has two special values other than the device id of
the allocated ctty:
-1: CTTY is not initialized yet. Can be associated with the TTY
which is associated with the session leader.
-2: CTTY has been released by setsid(). Can be associate only with
new TTY which is not associated with any other session as CTTY,
but cannot be associate with the TTYs already associated with
other sessions.
This patch adds the comments in some source files.
Suggested-by: Corinna Vinschen <corinna@vinschen.de>
Signedoff-by: Takashi Yano <takashi.yano@nifty.ne.jp>
The commit 25c4ad6ea5 did not fix the CTTY behavior enough. For
example, in the following test case, TTY will be associated as
a CTTY on the second open() call even though the TTY is already
CTTY of another session. This patch fixes the issue.
#include <unistd.h>
#include <sys/fcntl.h>
int main()
{
if (fork () == 0) {
char *tty = ttyname(0);
int fd;
setsid();
fd = open(tty, O_RDWR);
close(fd);
fd = open(tty, O_RDWR);
usleep (60000000L);
}
return 0;
}
Fixes: 25c4ad6ea5 ("Cygwin: pinfo: Align CTTY behavior to the
statement of POSIX.")
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
After the commit 30add3e6b3, the problem:
https://cygwin.com/pipermail/cygwin/2022-December/252759.html
occurs rarely. It seems that myself_pinfo should be initialized
where the timing before child_copy() and after cygheap allocation.
This patch moves the initialization there.
Fixes: 30add3e6b3 ("Cygwin: exec: don't access cygheap before it's
initialized")
Reported-by: Brian Inglis <Brian.Inglis@Shaw.ca>
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
The code computing the mask of pending signals used the per-queued
signal TLS pointer without checking it for NULL. Fix this by using
the process-wide signal mask in that case.
Fixes: 195169186b ("Cygwin: wait_sig: allow to compute process-wide mask of pending signals")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Since 4e7817498e, we're just running the tests against the installed
DLL. We're arranging to put the build directory on the path, but since
it doesn't contain cygwin1.dll (since it's built with a different name
and renamed on installation), that doesn't have any effect.
Arrange to place the just-built DLL into a directory which the testsuite
can place on it's path (while running the test, but not while compiling
it).
Also fix any remaining references to cygwin0.dll in testsuite,
documentation and comments.
Fixes: 4e7817498e ("Cygwin: Makefile: Drop all the "test dll" considerations")
The code generating the signal info in _pinfo::siginfo() and in
commune_process() are doing the same thing. Create a local static
function commune_process_siginfo() to have the code in one place
only. Remove a useless sigpending() call.
Fixes: 9a3c058f66 ("Cygwin: /proc/<PID>/status: Fill SigPnd, SigBlk and SigIgn values with life")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Previously, the console device could not be accessed from other terminals.
Due to this limitation, GNU screen and tmux cannot be opened in console.
With this patch, console device can be accessed from other TTYs, such as
other consoles or ptys. Thanks to this patch, screen and tmux get working
in console.
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
The devices /dev/conin,conout,console were wrongly visible from ptys,
though they are inaccessible. This is because fhandler_console::exists()
returns true due to existing invisible console. This patch makes these
devices invisible from ptys.
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
POSIX states "A terminal may be the controlling terminal for at most
one session."
https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap11.html
However, in cygwin, multiple sessions could be associated with the
same TTY. This patch aligns CTTY behavior to the statement of POSIX.
Reviewed-by: Corinna Vinschen <corinna@vinschen.de>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
... so that all of 'exit', '_exit', '_Exit' work. 'exit' thus becomes the
standard 'newlib/libc/stdlib/exit.c' -- and functions registered via 'atexit'
are now called at return from 'main' or manual 'exit' invocation.
https://cygwin.com/pipermail/cygwin/2022-December/252737.html
If the less is started from non-cygwin shell and window size is
changed, it will hang-up when quitting. The cause of the proglem is
that less uses longjump() in signal handler. If the signal handler
is called while cygwin is acquiring the mutex, cygwin loses the
chance to release mutex. With this patch, the mutex is released
just before calling kill_pgrp() and re-acquired when kill_pgrp()
returns.
Reported-by: Gregory Mason <grmason@epic.com>
Signed-off-by: Takashi Yano <takashi.yano@nifty.ne.jp>
After 90236c3a2c, the testsuite is failing, as the cygwin0.dll
referenced by the implib that testsuite programs are linked with doesn't
exist anymore.
We don't need to make and link the testsuite with a specially named DLL,
as the cygwin DLL (since 526b0fbca3) takes into consideration the path
it's executing from to define separate "Cygwin installations", which
don't interact.
Fixes: 90236c3a2c ("Cygwin: Makefile: build new-cygwin1.dll in a single step")
Commit c1023ee353 introduced a split between mount flags and
path flags. It didn't initialize symlink_info::path_flags in
path_conv::check, because that's done in symlink_info::check.
However, there are two code paths expecting symlink_info::path_flags
being already initialized and both skip symlink_info::check.
Make sure symlink_info::path_flags is initalized to 0 early in
path_conv::check.
Fixes: c1023ee353 ("Cygwin: path_conv: decouple path_types from mount types")
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Rather than guessing, based on just the presence of libbfd, add an
explicit configuration option, to build dumper or not, defaulting to
building it.
This might have some use when bootstrapping Cygwin for a new
architecture, or when building your own Cygwin-targetted cross-compiler,
rather than installing one from the copr, along with the dependencies of
libbfd.
Tweak slightly to allow implementing entire {w}mem{p}{cpy,move}
family:
Add WIDE macro processing for wmem* and POST macro processing for
memp* functions.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Since no other port uses this custom libgloss multi-build.in logic,
and it's making things difficult to unify, drop it all. The set of
installed objects and their content should be the same.
There is a difference in the builds: currently we compile all the
objects in this subdir twice, but only a subset of them use a diff
set of flags, and are actually installed (the librdimon.a and its
objects). So this change speeds things up by removing the duplicate
compilation.
There is a short term cost in having to duplicate the compile rules
for the files that are different, but this is minor when compared to
being able to delete the unused multi-build logic (which we'll do in
a sep commit), and we'll be able to clean this up when we move the
code to unified automake.
None of this should be confused with the common multilib logic.
This is *multi-build* which is processed in parallel.
This logic looks like it was copied from the arm port, but it isn't
actually used here. Since no other port uses this custom libgloss
multi-build.in logic, and it's making things difficult to unify,
and aarch64 isn't even using it, drop it all. The set of installed
objects and their content should be the same.
Once we move this to unified automake, if we want to readd support
for subdir multi-builds, it'll be a lot easier as we can just add
another set of objects with custom flags.
None of this should be confused with the common multilib logic.
This *multi-build* which is processed in parallel.
It seems there is a swapped logic in one of the subcases of
setjmp.S for MIPS: when the FPU registers are 64-bit within
a 32-bit aligned jmp_buf, the code realigns the pointers
before doing 64-bit writes, but the branch logic is swapped:
we must avoid the address adjustement when bit 2 is zero
(that is, the address is already 8-byte aligned).
This always triggers an address error when run, as tested
on a MIPS VR4300 with O64 ABI.
The implementation of expf() explains how approximation in the range [0 - 0.34] is done. The comment describes the "Reme" algorithm for constructing the polynomial. This is a typo and should be the "Remez" algorithm. The remez algorithm (or minimax) is used to calculate the coefficients of polynomials in other implementations of exp(0 and log().
See more:
https://en.wikipedia.org/wiki/Remez_algorithm
This implements a set of vectorized math routines to be used by the
compiler auto-vectorizer. Versions for vectors with 2 lanes up to
64 lanes (in powers of 2) are provided.
These routines are based on the scalar versions of the math routines in
libm/common, libm/math and libm/mathfp. They make extensive use of the GCC
C vector extensions and GCN-specific builtins in GCC.
As per the arm Procedure Call Standard for the Arm Architecture
section 6.1.2 [1], VFP registers s16-s31 (d8-d15, q4-q7) must be
preserved across subroutine calls.
The current setjmp/longjmp implementations preserve only the core
registers, with the jump buffer size too small to store the required
co-processor registers.
In accordance with the C Library ABI for the Arm Architecture
section 6.11 [2], this patch sets _JBTYPE to long long adjusting
_JBLEN to 20.
It also emits vfp load/store instructions depending on architectural
support, predicated at compile time on ACLE feature-test macros.
[1] https://github.com/ARM-software/abi-aa/blob/main/aapcs32/aapcs32.rst
[2] https://github.com/ARM-software/abi-aa/blob/main/clibabi32/clibabi32.rst
Victor L. Do Nascimento
Takashi Yano
Corinna Vinschen
Jon Turney
Mike Frysinger
CompilerAI Research Group
Brian Inglis
Thomas Schwinge
Giovanni Bajo
Jeff Johnston
Nadav Rotem
Kwok Cheung Yeung