diff options
Diffstat (limited to 'libc/sysdeps/linux/sparc/setcontext.S')
| -rw-r--r-- | libc/sysdeps/linux/sparc/setcontext.S | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/libc/sysdeps/linux/sparc/setcontext.S b/libc/sysdeps/linux/sparc/setcontext.S new file mode 100644 index 000000000..f9da21563 --- /dev/null +++ b/libc/sysdeps/linux/sparc/setcontext.S @@ -0,0 +1,118 @@ +/* Install given context. + Copyright (C) 2008-2016 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by David S. Miller <davem@davemloft.net>, 2008. + + 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 + <http://www.gnu.org/licenses/>. */ + +#include <sysdep.h> + +#include "ucontext_i.h" + +#define ST_FLUSH_WINDOWS 3 + +/* int __setcontext (const ucontext_t *ucp) + + Restores the machine context in UCP and thereby resumes execution + in that context. + + This implementation is intended to be used for *synchronous* context + switches only. Therefore, it does not have to restore anything + other than the PRESERVED state. */ + +ENTRY(__setcontext) + save %sp, -112, %sp + + mov SIG_SETMASK, %o0 + add %i0, UC_SIGMASK, %o1 + clr %o2 + mov 8, %o3 + mov __NR_rt_sigprocmask, %g1 + ta 0x10 + + /* This is a bit on the expensive side, and we could optimize + the unwind similar to how the 32-bit sparc longjmp code + does if performance of this routine really matters. */ + ta ST_FLUSH_WINDOWS + + ldub [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_EN], %g1 + cmp %g1, 0 + be 1f + nop + ld [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_FSR], %fsr + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D0], %f0 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D2], %f2 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D4], %f4 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D6], %f6 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D8], %f8 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D10], %f10 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D12], %f12 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D14], %f14 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D16], %f16 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D18], %f18 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D20], %f20 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D22], %f22 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D24], %f24 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D26], %f26 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D28], %f28 + ldd [%i0 + UC_MCONTEXT + MC_FPREGS + FPU_D30], %f30 +1: + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_Y], %g1 + wr %g1, 0x0, %y + + /* We specifically do not restore %g1 since we need it here as + a temporary. */ + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G2], %g2 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G3], %g3 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G4], %g4 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G5], %g5 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G6], %g6 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_G7], %g7 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O1], %i1 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O2], %i2 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O3], %i3 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O4], %i4 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O5], %i5 + ld [%i0 + UC_MCONTEXT + MC_GREGS + GREG_O6], %i6 + restore + ld [%o0 + UC_MCONTEXT + MC_GREGS + GREG_O7], %o7 + ld [%o0 + UC_MCONTEXT + MC_GREGS + GREG_PC], %g1 + jmpl %g1, %g0 + ld [%o0 + UC_MCONTEXT + MC_GREGS + GREG_O0], %o0 +END(__setcontext) + +weak_alias (__setcontext, setcontext) + +/* This is the helper code which gets called if a function which is + registered with 'makecontext' returns. In this case we have to + install the context listed in the uc_link element of the context + 'makecontext' manipulated at the time of the 'makecontext' call. + If the pointer is NULL the process must terminate. */ + +ENTRY(__start_context) + ld [%sp + (16 * 4)], %g1 + cmp %g1, 0 + be,a 1f + clr %o0 + call __setcontext + mov %g1, %o0 + /* If this returns (which can happen if the syscall fails) we'll + exit the program with the return error value (-1). */ +1: call HIDDEN_JUMPTARGET(exit) + nop + /* The 'exit' call should never return. In case it does cause + the process to terminate. */ + unimp +END(__start_context) |