glibc/sysdeps/unix/sysv/linux/riscv/makecontext.c

79 lines
2.7 KiB
C
Raw Normal View History

2018-01-29 18:28:32 +00:00
/* Create new context. RISC-V version.
Copyright (C) 2001-2021 Free Software Foundation, Inc.
2018-01-29 18:28:32 +00:00
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
Prefer https to http for gnu.org and fsf.org URLs Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 05:40:42 +00:00
<https://www.gnu.org/licenses/>. */
2018-01-29 18:28:32 +00:00
#include <sysdep.h>
#include <sys/asm.h>
#include <sys/ucontext.h>
#include <stdarg.h>
#include <assert.h>
void
__makecontext (ucontext_t *ucp, void (*func) (void), int argc,
long int a0, long int a1, long int a2, long int a3, long int a4,
...)
{
extern void __start_context (void) attribute_hidden;
long int i, sp;
_Static_assert (REG_NARGS == 8, "__makecontext assumes 8 argument registers");
/* Set up the stack. */
sp = ((long int) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size) & ALMASK;
/* Set up the register context.
ra = s0 = 0, terminating the stack for backtracing purposes.
s1 = the function we must call.
s2 = the subsequent context to run. */
ucp->uc_mcontext.__gregs[REG_RA] = 0;
ucp->uc_mcontext.__gregs[REG_S0] = 0;
ucp->uc_mcontext.__gregs[REG_S1] = (long int) func;
ucp->uc_mcontext.__gregs[REG_S2] = (long int) ucp->uc_link;
ucp->uc_mcontext.__gregs[REG_SP] = sp;
ucp->uc_mcontext.__gregs[REG_PC] = (long int) &__start_context;
/* Put args in a0-a7, then put any remaining args on the stack. */
ucp->uc_mcontext.__gregs[REG_A0 + 0] = a0;
ucp->uc_mcontext.__gregs[REG_A0 + 1] = a1;
ucp->uc_mcontext.__gregs[REG_A0 + 2] = a2;
ucp->uc_mcontext.__gregs[REG_A0 + 3] = a3;
ucp->uc_mcontext.__gregs[REG_A0 + 4] = a4;
if (__glibc_unlikely (argc > 5))
{
va_list vl;
va_start (vl, a4);
long reg_args = argc < REG_NARGS ? argc : REG_NARGS;
for (i = 5; i < reg_args; i++)
ucp->uc_mcontext.__gregs[REG_A0 + i] = va_arg (vl, long);
long int stack_args = argc - reg_args;
if (stack_args > 0)
{
sp = (sp - stack_args * sizeof (long int)) & ALMASK;
ucp->uc_mcontext.__gregs[REG_SP] = sp;
for (i = 0; i < stack_args; i++)
((long int *) sp)[i] = va_arg (vl, long int);
}
va_end (vl);
}
}
weak_alias (__makecontext, makecontext)