Commit Graph

140 Commits (4975ba90519f5d38fd206476cc358ff3a7d83eb3)

Author SHA1 Message Date
Sören Tempel d0b03541bf common-trampoline: Ensure omission of frame-pointer
Some architecture-specific implementations of the FETCH_LINKPTR
(e.g. the one for x86) attempt to find the linkptr relative to the
stack pointer. Therefore, they make assumption about the value of
the SP at the point where the FETCH_LINKPTR code is executed. This
means that we don't want the C compiler to mess with our SP.

For this purpose, local variables in this function are currently
declared using the register storage specifier. Additionally, we
need to make sure that a frame pointer is /always/ omitted for
this function. On x86 Alpine, the frame pointer is presently not
omitted with GCC 13 when using -Os, therefore the tests segfault
with -Os on Alpine presently.

Fixes #52
2024-08-07 17:46:50 -07:00
Volker Christian 124a962b39 aarch64: fix return value if getcontext was used to acquire the current context.
x0 hast to be 0 in case setcontext is called with a context acquired by getcontext.
Thus x0=0 must be stored in getcontext.
2024-08-07 17:45:47 -07:00
Volker Christian 9e5de65076 libucontext: Add patch fixing return values of get/set/swapcontext
The arm ABI defines that the value in register r0 is used as the return
value of a function. To indicate success for get/set/swapcontext (return
value of 0) the register r0 must contain zero at the end of the function
call. Thus set r0 to zero and store it in the context. This context
is restored later and indicate successful execution, because r0 is 0.

The order registers are stored has changed so that only one additional
instruction (mov r0, #0) needs to be added to fix the return value
bug for get/set/swapcontext.

Signed-off-by: Volker Christian <me@vchrist.at>
2024-08-07 17:44:43 -07:00
Richard Campbell 3044c2b908 Fixed empty TYPE(__proc) causing linker issues on 32-bit arm 2022-03-23 15:18:39 -07:00
Richard Campbell 7bc3e90984 Added arm conditional vfp save/restore 2022-03-04 10:35:25 -08:00
Ariadne Conill 0a72eff002 or1k: add freestanding bits 2022-02-13 09:06:58 +00:00
Ariadne Conill 973e61441a or1k: add getcontext/setcontext/swapcontext 2022-02-13 08:58:38 +00:00
Ariadne Conill 00128f7575 or1k: add makecontext and trampoline 2022-02-13 08:58:03 +00:00
Ariadne Conill 7fc08a6dc6 or1k: add definitions 2022-02-13 08:57:36 +00:00
Ariadne Conill a51dce6e2c common-trampoline: initialize link pointer to NULL 2022-02-13 07:35:23 +00:00
Richard Campbell 1e37bf30f9 Adjusted location within ucontext of saved/restored FP regs for compatibility 2021-07-30 12:45:12 -07:00
Richard Campbell 06303df1cd Added saving/restoring of bottom 64 bits of d8-d15 per AAPCS64 2021-07-29 18:45:48 -07:00
Peng Fan a182fee66a Add support for Loongarch64
Signed-off-by: Peng Fan <fanpeng@loongson.cn>
2021-06-04 09:07:38 -06:00
Ariadne Conill fb1d203677 everywhere: drop _GNU_SOURCE requirement 2021-03-09 00:25:13 -07:00
Ariadne Conill 1ad20e03e5 add riscv32 port 2021-03-09 00:00:26 -07:00
osy 9b1d8f01a6 aarch64: remove usage of FUNC macro for clang
Clang's arm64 assembler does not support multiple directives on a single
line. C macros ALWAYS expand to a single line.
2021-03-08 15:13:34 -08:00
osy 5d66c194a7 x86_64: define reg names if not defined
_GNU_SOURCE can be defined without defining REG_X macros so it is not a
good indicator. (QEMU for example defines it in the build system.) x86
and x86_64 should have consistant looking defs.h so ifndef guards are
added to each REG_X definition.
2021-03-08 14:02:58 -08:00
osy f3e1b876c7 project: move freestanding include headers
This is needed because in libucontext.h we include "libucontext/bits.h".
We therefore need to have bits.h in somepath/libucontext/bits.h. In the
Makefile, somepath/freestanding/bits.h was copied to the right path but
in the meson build system, the include copy happens at the end.
2021-03-08 13:02:27 -08:00
Daniel Kolesa 4801f0bdd8 all: mark the trampoline symbol hidden
this should not be a part of the public ABI
2021-01-08 15:17:13 +01:00
Daniel Kolesa efa6464e41 ppc, ppc64: do not use ALIAS for libucontext_swapcontext 2021-01-08 15:17:11 +01:00
Ariadne Conill b1902729f7 aarch64: fix freestanding structure layout when building with clang 2021-01-08 11:19:01 +00:00
Ariadne Conill 5546fde1e5 aarch64: add static asserts for struct layout 2021-01-08 10:39:47 +00:00
Ariadne Conill 09f78ddc28 alias __makecontext too 2021-01-08 10:37:27 +00:00
osy fffb55011b arm: fix broken FETCH_LINKPTR 2021-01-08 03:20:14 -07:00
osy f7eed30132 build: guard _GNU_SOURCE define if build system defines it 2021-01-08 03:16:05 -07:00
osy d31c95a11a build: remove -DLIBUCONTEXT_ASSEMBLY
Meson does not support separate defines for .S compile.
2021-01-08 03:11:25 -07:00
Ariadne Conill e4233715f3 mips: use PROC_NAME where appropriate 2021-01-08 03:10:10 -07:00
osy 163c11d989 build: support mach-o ABI 2021-01-08 03:05:06 -07:00
osy 73d5e101ad build: respect EXPORT_UNPREFIXED for libucontext_makecontext 2021-01-08 03:02:43 -07:00
Ariadne Conill e45956896a common-trampoline: use register keyword to force register allocation 2021-01-08 03:00:37 -07:00
osy e1e6508af2 defs: use register output only for FETCH_LINKPTR 2021-01-08 02:59:43 -07:00
Ariadne Conill 638770cfd0 x86_64: add static assert verifying memory layout 2021-01-08 02:56:45 -07:00
Ariadne Conill 39a2958561 add previous ABI symbols 2021-01-08 02:30:50 -07:00
Daniel Kolesa cf05112306 ppc, ppc64: use common ALIAS/FUNC/END macros 2021-01-08 04:52:46 +01:00
Daniel Kolesa 6026980cac ppc, ppc64: tag global symbols as functions
it is necessary to tag these symbols as functions otherwise the
linker gets confused; this previously manifested as the internal
functions (pre-rename) like __getcontext leaking into the symbol
table of things linked against libucontext that used the ucontext
POSIX API through the weak aliases

it also had another bad effect and that is if you tried to use
libucontext's API (post-rename), the linker would warn you during
compile time that the type is unknown, and the resulting program
would crash at runtime

after properly tagging everything, I no longer notice any leakage,
i.e. there don't seem to be any references to the aliased symbols
in the resulting symbol table when using the aliases, and using
the libucontext prefixed symbols directly also works
2021-01-08 04:27:27 +01:00
Ariadne Conill d81154a61c riscv64: port to C trampoline 2020-12-12 00:08:48 -07:00
Ariadne Conill 11a40293be riscv64: simplify the context swapping 2020-12-12 07:05:09 +00:00
Ariadne Conill 22b91690bc aarch64: move to C trampoline 2020-12-12 06:43:58 +00:00
Ariadne Conill afcca79d7b arm: move to C trampoline 2020-12-12 06:40:27 +00:00
Ariadne Conill 388edbe121 x86: port to use common trampoline 2020-12-12 06:32:01 +00:00
Ariadne Conill b6542e1a6a m68k: port to use common trampoline 2020-12-12 00:17:26 -06:00
Ariadne Conill 09d3f81dcf sh: use new common trampoline 2020-12-12 06:08:33 +00:00
Ariadne Conill 2d51d7bfa4 x86_64: add common trampoline code written in C, port to it 2020-12-11 23:04:47 -07:00
Ariadne Conill 5c3ca5a7e1 sh: add freestanding bits 2020-12-12 06:02:47 +00:00
Ariadne Conill 8d58adb3ba sh: fix up setcontext/swapcontext 2020-12-12 05:57:58 +00:00
Ariadne Conill dd7ef8a806 sh: makecontext: fix stack alignment 2020-12-12 05:04:39 +00:00
Ariadne Conill f9a3f65f5b sh: fix getcontext implementation 2020-12-12 05:04:17 +00:00
Ariadne Conill 82f734ab47 sh: makecontext: set up stack pointer in r15 2020-12-12 04:53:50 +00:00
Ariadne Conill da3c8d170f sh: add remaining port files 2020-12-11 23:18:04 +00:00
Ariadne Conill a42fb86da0 sh: add plausible swapcontext implementation 2020-12-11 22:37:21 +00:00