diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/loongarch/makecontext.c')
| -rw-r--r-- | sysdeps/unix/sysv/linux/loongarch/makecontext.c | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/loongarch/makecontext.c b/sysdeps/unix/sysv/linux/loongarch/makecontext.c new file mode 100644 index 0000000000..94a45bf4ad --- /dev/null +++ b/sysdeps/unix/sysv/linux/loongarch/makecontext.c @@ -0,0 +1,81 @@ +/* Create new context. + Copyright (C) 2022 Free Software Foundation, Inc. + + 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 + <https://www.gnu.org/licenses/>. */ + +#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; + unsigned long int *sp; + + _Static_assert(LARCH_REG_NARGS == 8, + "__makecontext assumes 8 argument registers"); + + /* Set up the stack. */ + sp = (unsigned long int *) + (((uintptr_t) 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[LARCH_REG_RA] = (uintptr_t) 0; + ucp->uc_mcontext.__gregs[LARCH_REG_S0] = (uintptr_t) 0; + ucp->uc_mcontext.__gregs[LARCH_REG_S1] = (uintptr_t) func; + ucp->uc_mcontext.__gregs[LARCH_REG_S2] = (uintptr_t) ucp->uc_link; + ucp->uc_mcontext.__gregs[LARCH_REG_SP] = (uintptr_t) sp; + ucp->uc_mcontext.__pc = (uintptr_t) &__start_context; + + /* Put args in a0-a7, then put any remaining args on the stack. */ + ucp->uc_mcontext.__gregs[LARCH_REG_A0 + 0] = (uintptr_t) a0; + ucp->uc_mcontext.__gregs[LARCH_REG_A0 + 1] = (uintptr_t) a1; + ucp->uc_mcontext.__gregs[LARCH_REG_A0 + 2] = (uintptr_t) a2; + ucp->uc_mcontext.__gregs[LARCH_REG_A0 + 3] = (uintptr_t) a3; + ucp->uc_mcontext.__gregs[LARCH_REG_A0 + 4] = (uintptr_t) a4; + + if (__glibc_unlikely (argc > 5)) + { + va_list vl; + va_start (vl, a4); + + long int reg_args = argc < LARCH_REG_NARGS ? argc : LARCH_REG_NARGS; + for (long int i = 5; i < reg_args; i++) + ucp->uc_mcontext.__gregs[LARCH_REG_A0 + i] = va_arg (vl, unsigned long int); + + long int stack_args = argc - reg_args; + if (stack_args > 0) + { + sp = (unsigned long int *) + (((uintptr_t) sp - stack_args * sizeof (long int)) & ALMASK); + ucp->uc_mcontext.__gregs[LARCH_REG_SP] = (uintptr_t) sp; + for (long int i = 0; i < stack_args; i++) + sp[i] = va_arg (vl, unsigned long int); + } + + va_end (vl); + } +} + +weak_alias (__makecontext, makecontext) |