diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/aarch64/morello/swapcontext.S')
| -rw-r--r-- | sysdeps/unix/sysv/linux/aarch64/morello/swapcontext.S | 120 |
1 files changed, 120 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/aarch64/morello/swapcontext.S b/sysdeps/unix/sysv/linux/aarch64/morello/swapcontext.S new file mode 100644 index 0000000000..90e4eca413 --- /dev/null +++ b/sysdeps/unix/sysv/linux/aarch64/morello/swapcontext.S @@ -0,0 +1,120 @@ +/* Modify saved context. + + Copyright (C) 2009-2022 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 "ucontext_i.h" +#include "ucontext-internal.h" + +/* int swapcontext (ucontext_t *oucp, const ucontext_t *ucp) */ + + .text +ENTRY(__swapcontext) + /* Set the value returned when swapcontext() returns in this context. + And set up x1 to become the return address of the caller, so we + can return there with a normal RET instead of an indirect jump. */ + + /* For Morello, the capability registers are located in after the FPSIMD + context. */ + add c9, c0, #oEXTENSION + FPSIMD_CONTEXT_SIZE + + /* Write the context extension morello header. */ + mov w3, #(MORELLO_MAGIC & 0xffff) + movk w3, #(MORELLO_MAGIC >> 16), lsl #16 + str w3, [c9, #oCHEAD + oMAGIC] + mov w3, #MORELLO_CONTEXT_SIZE + str w3, [c9, #oCHEAD + oSIZE] + + add c10, c9, #oC0 + stp czr, c30, [c10, 0 * SZCREG] + /* Arrange the oucp context to return to 2f. */ + adr c30, 2f + + stp c18, c19, [c10, 18 * SZCREG] + stp c20, c21, [c10, 20 * SZCREG] + stp c22, c23, [c10, 22 * SZCREG] + stp c24, c25, [c10, 24 * SZCREG] + stp c26, c27, [c10, 26 * SZCREG] + stp c28, c29, [c10, 28 * SZCREG] + str c30, [c10, 30 * SZCREG] + str c30, [c9, oPCC] + mov c11, csp + str c11, [c9, oCSP] + + /* Figure out where to place the fpsimd context extension + block. */ + add c9, c0, #oEXTENSION + + /* Write the context extension fpsimd header. */ + mov w3, #(FPSIMD_MAGIC & 0xffff) + movk w3, #(FPSIMD_MAGIC >> 16), lsl #16 + str w3, [c9, #oHEAD + oMAGIC] + mov w3, #FPSIMD_CONTEXT_SIZE + str w3, [c9, #oHEAD + oSIZE] + + /* Fill in the FP SIMD context. */ + add c10, c9, #oV0 + 8 * SZVREG + stp q8, q9, [c10], #2 * SZVREG + stp q10, q11, [c10], #2 * SZVREG + stp q12, q13, [c10], #2 * SZVREG + stp q14, q15, [c10], #2 * SZVREG + + add c10, c9, #oFPSR + mrs x4, fpsr + str w4, [c10, #oFPSR - oFPSR] + mrs x4, fpcr + str w4, [c10, #oFPCR - oFPSR] + + /* Write the termination context extension header after the Morello + context. */ + add c9, c9, #FPSIMD_CONTEXT_SIZE + MORELLO_CONTEXT_SIZE + str wzr, [c9, #oHEAD + oMAGIC] + str wzr, [c9, #oHEAD + oSIZE] + + /* Preserve ucp. */ + mov c11, c1 + + /* rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, &oucp->uc_sigmask, + _NSIG8) */ + /* Grab the signal mask */ + /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */ + add c2, c0, #UCONTEXT_SIGMASK + mov x0, SIG_BLOCK + mov x1, 0 + mov x3, _NSIG8 + mov x8, SYS_ify (rt_sigprocmask) + svc 0 + cbnz x0, 1f + + mov c15, c30 + mov c0, c11 + bl JUMPTARGET (__setcontext) + mov c30, c15 + RET + +1: + b C_SYMBOL_NAME(__syscall_error) +2: + /* The oucp context is restored here via an indirect branch, + x1 must be restored too which has the real return address. */ + mov c30, c1 + RET +PSEUDO_END (__swapcontext) +weak_alias (__swapcontext, swapcontext) |