/* Save current context. Copyright (C) 2009-2016 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 . */ #include #include "ucontext_i.h" #include "ucontext-internal.h" /* int getcontext (ucontext_t *ucp) Returns 0 on success -1 and errno on failure. */ .text ENTRY(__getcontext) /* The saved context will return to the getcontext() call point with a return value of 0 */ str xzr, [x0, oX0 + 0 * SZREG] stp x18, x19, [x0, oX0 + 18 * SZREG] stp x20, x21, [x0, oX0 + 20 * SZREG] stp x22, x23, [x0, oX0 + 22 * SZREG] stp x24, x25, [x0, oX0 + 24 * SZREG] stp x26, x27, [x0, oX0 + 26 * SZREG] stp x28, x29, [x0, oX0 + 28 * SZREG] str x30, [x0, oX0 + 30 * SZREG] /* Place LR into the saved PC, this will ensure that when switching to this saved context with setcontext() control will pass back to the caller of getcontext(), we have already arrange to return the appropriate return value in x0 above. */ str x30, [x0, oPC] /* Save the current SP */ mov x2, sp str x2, [x0, oSP] /* Initialize the pstate. */ str xzr, [x0, oPSTATE] /* Figure out where to place the first context extension block. */ add x2, x0, #oEXTENSION /* Write the context extension fpsimd header. */ mov w3, #(FPSIMD_MAGIC & 0xffff) movk w3, #(FPSIMD_MAGIC >> 16), lsl #16 str w3, [x2, #oHEAD + oMAGIC] mov w3, #FPSIMD_CONTEXT_SIZE str w3, [x2, #oHEAD + oSIZE] /* Fill in the FP SIMD context. */ add x3, x2, #oV0 + 8 * SZVREG stp q8, q9, [x3], # 2 * SZVREG stp q10, q11, [x3], # 2 * SZVREG stp q12, q13, [x3], # 2 * SZVREG stp q14, q15, [x3], # 2 * SZVREG add x3, x2, oFPSR mrs x4, fpsr str w4, [x3] mrs x4, fpcr str w4, [x3, oFPCR - oFPSR] /* Write the termination context extension header. */ add x2, x2, #FPSIMD_CONTEXT_SIZE str xzr, [x2, #oHEAD + oMAGIC] str xzr, [x2, #oHEAD + oSIZE] /* Grab the signal mask */ /* rt_sigprocmask (SIG_BLOCK, NULL, &ucp->uc_sigmask, _NSIG8) */ add x2, x0, #UCONTEXT_SIGMASK mov x0, SIG_BLOCK mov x1, 0 mov x3, _NSIG8 mov x8, SYS_ify (rt_sigprocmask) svc 0 cbnz x0, 1f /* Return 0 for success */ mov x0, 0 RET 1: b C_SYMBOL_NAME(__syscall_error) PSEUDO_END (__getcontext) weak_alias (__getcontext, getcontext)