21 Commits

Author SHA1 Message Date
mmel
9062907b18 Publish __aeabi_uidiv and __aeabi_idiv as compatible symbols from libc.
Due to bug[1] in libcompiler_rt, all symbols declared by
DEFINE_AEABI_FUNCTION_ALIAS() are not hidden. All these but two
are explicitly exported from libc and don't causes problems.

Remaining two, __aeabi_uidiv and __aeabi_idiv, infecting all
non-versioned shared libraries. And these symbols are consumed
by many (if not all) packages[2].

As workaround, export these from libc as compatible symbols,
in global namespace. With this, these are still visible for
rtld, but static linker doesn't use then.

[1]
DEFINE_AEABI_FUNCTION_ALIAS() macro uses '.set' directive for
declaration of aliased symbol. Unfortunately, '.set' doesn't
inherit visibility of base symbol, and macro don't explicitly
sets visibility for aliased one.

[2]
Given symbols are exported from non-versioned libraries only if
library itself uses them. So, if world is built for CPU with
HW divide, these function are not used and given symbols are
not exported. By this, contents of these libraries is not stable,
and all packages fails to run.

Note: Due to r313823 I'm forced to commit this too early, without
leave enough time for proper review.

MFC after: 1 month
Differential Revision: https://reviews.freebsd.org/D9632
2017-02-17 11:16:19 +00:00
ngie
32a5b43489 Replace dot-dot relative pathing with SRCTOP-relative paths where possible
This reduces build output, need for recalculating paths, and makes it clearer
which paths are relative to what areas in the source tree. The change in
performance over a locally mounted UFS filesystem was negligible in my testing,
but this may more positively impact other filesystems like NFS.

LIBC_SRCTOP was left alone so Juniper (and other users) can continue to
manipulate lib/libc/Makefile (and other Makefile.inc's under lib/libc) as
include Makefiles with custom options.

Discussed with:	marcel, sjg
MFC after:	1 week
Reviewed by:	emaste
Sponsored by:	Dell EMC Isilon
Differential Revision:	https://reviews.freebsd.org/D9207
2017-01-20 03:23:24 +00:00
imp
3b518c4dc1 Make armv6 hard float abi by default. Kill armv6hf.
Allow CPUTYPE=soft to build the current soft-float abi libraries.
Add UPDATING entry to announce this.

Approved by: re@ (gjb)
2016-05-18 06:01:18 +00:00
andrew
b58948f222 Revert a change that sneeked with 297619 2016-04-06 16:50:18 +00:00
andrew
1c933ace1f Disable support for compat syscalls on arm64. These symbols were never
shipped since arm64 exists only on 11+.

Submitted by:	brooks
Reviewed by:	emaste, imp
2016-04-06 16:09:10 +00:00
kib
2b6ac44d5d Annotate arm userspace assembler sources stating their tolerance to
the non-executable stack.

Reviewed by:	andrew
Sponsored by:	The FreeBSD Foundation
2015-09-29 16:09:58 +00:00
andrew
08e22f2cb8 Export the ARM __aeabi_mem* functions from libc, they are needed by the gcc
from ports as it doesn't include these in the copy of libgcc it installs
uses.

Obtained from:	ABT Systems Ltd
2015-06-16 16:40:25 +00:00
andrew
ec75d7f7fb Use a register to set the cpsr bits. The ip register is safe to be changed
within all of these functions, and is only stored in some to correctly pad
the stack.

This will be needed to build as Thumb-2 as, unlike with ARM instructions,
the msr instruction only takes a register as the input.
2015-05-31 09:07:26 +00:00
andrew
07deb5ca15 Teach bits of libc about Thumb. This adds the if-then instructions needed
to handle the ARM conditional execution.

While here fix a bug found by this in the hard-float code, cc is the
opposite of cs. The former is used for 'less than' in floating-point code
and is executed when the C (carry) bit is clear, the latter is used when
greater than, equal, or unordered, and is executed when the C bit is set.
2015-05-12 10:03:14 +00:00
dim
59eeccaa33 Apparently more Makefiles use stuff from compiler-rt, so fix them up
too.  (This did not show during a make universe, strangely.)
2015-01-08 20:11:38 +00:00
andrew
ae2dabfbf3 Add support for the __aeabi_c*cmp* functions. These are similar to the
existing functions with the exception they use the condition flags to
store the result.

Differential Revision:	https://reviews.freebsd.org/D872
Silence from:	current@ and numerics@
MFC after:	1 week
2014-10-14 14:27:51 +00:00
andrew
47431db4e9 Clean up detection of hard-float ABIs. As with big-endian in r272368 we
can check against arm*hf*.
2014-10-01 16:08:19 +00:00
imp
79c623db6a From https://sourceware.org/ml/newlib/2014/msg00113.html
By Richard Earnshaw at ARM
>
>GCC has for a number of years provides a set of pre-defined macros for
>use with determining the ISA and features of the target during
>pre-processing.  However, the design was always somewhat cumbersome in
>that each new architecture revision created a new define and then
>removed the previous one.  This meant that it was necessary to keep
>updating the support code simply to recognise a new architecture being
>added.
>
>The ACLE specification (ARM C Language Extentions)
>(http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.set.swdev/index.html)
>provides a much more suitable interface and GCC has supported this
>since gcc-4.8.
>
>This patch makes use of the ACLE pre-defines to map to the internal
>feature definitions.  To support older versions of GCC a compatibility
>header is provided that maps the traditional pre-defines onto the new
>ACLE ones.

Stop using __FreeBSD_ARCH_armv6__ and switch to __ARM_ARCH >= 6 in the
couple of places in tree. clang already implements ACLE. Add a define
that says we implement version 1.1, even though the implementation
isn't quite complete.
2014-08-14 04:20:13 +00:00
ian
a65b4d5170 Add dl_unwind_find_exidx() for ARM EABI, required for C++ exception
handling.  For statically linked apps this uses the __exidx_start/end
symbols set up by the linker.  For dynamically linked apps it finds the
shared object that contains the given address and returns the location and
size of the exidx section in that shared object.

The dl_unwind_find_exidx() name is used by other BSD projects and Android,
and is mentioned in clang 3.5 comments as "the BSD interface" for finding
exidx data.  GCC (in libgcc_s) expects the exact same API and functionality
to be provided by a function named __gnu_Unwind_Find_exidx(), so we provide
that with an alias ("strong reference").

Reviewed by:	kib@
MFC after:	1 week
2014-07-19 22:13:27 +00:00
andrew
8842d57879 Add a new ARM TARGET_ARCH, armv6hf. This is considered experimental.
This targets the existing ARMv6 and ARMv7 SoCs that contain a VFP unit.
This is an optional coprocessors may not be present in all devices, however
it appears to be in all current SoCs we support.

armv6hf targets the VFP variant of the ARM EABI and our copy of gcc is too
old to support this. Because of this there are a number of WITH/WITHOUT
options that are unsupported and must be left as the default value. The
options and their required value are:
 * WITH_ARM_EABI
 * WITHOUT_GCC
 * WITHOUT_GNUCXX

In addition, without an external toolchain, the following need to be left
as their default:
 * WITH_CLANG
 * WITH_CLANG_IS_CC

As there is a different method of passing float and double values to
functions the ABI is incompatible with existing armv6 binaries. To use
this a full rebuild of world is required. Because no floating point values
are passed into the kernel an armv6 kernel with VFP enabled will work with
an armv6hf userland and vice versa.
2014-03-23 12:49:25 +00:00
andrew
47e8ffc6b7 Remove an extra 1 in an #if line
Reported by:	ian@
2014-03-16 14:21:09 +00:00
andrew
5d9911c770 Fix the spelling of function.
Reported by:	ian@
2014-03-16 14:19:46 +00:00
andrew
f643cc2261 Add an optimised version of the float and double helper functions. These
are only used on armv6 when the vfp unit is detected. They will also be
available for the upcoming armv6hf platform, however while not used by
default there will need to be defined for any software that calls them
directly.
2014-03-16 13:16:30 +00:00
marcel
99c9726a00 Replace use of ${.CURDIR} by ${LIBC_SRCTOP} and define ${LIBC_SRCTOP}
if not already defined. This allows building libc from outside of
lib/libc using a reach-over makefile.

A typical use-case is to build a standard ILP32 version and a COMPAT32
version in a single iteration by building the COMPAT32 version using a
reach-over makefile.

Obtained from:	Juniper Networks, Inc.
2014-03-04 02:19:39 +00:00
andrew
3303d1f6a9 When clang builds libc it may insert calls to __aeabi_* functions. Normally
this is not a problem as they are resolved by libgcc. The exception is for
the __aeabi_mem* functions. These call back into libc to the appropriate
function. This causes issues for static binaries as we only link against
libc once so there is no way for it to call into libgcc and back.

The fix for this is to include these symbols in libc but keep them hidden
so binaries use the libgcc version.
2013-02-12 06:04:51 +00:00
andrew
ee70ac6d85 Add the required __aeabi_* functions to libc.
The floating point functions are here rather than compiler-rt because the
libc softfloat code allows us to set the rounding mode.
2013-01-19 05:33:55 +00:00