diff options
Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/tile/setcontext.S')
| -rw-r--r-- | ports/sysdeps/unix/sysv/linux/tile/setcontext.S | 201 |
1 files changed, 201 insertions, 0 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/tile/setcontext.S b/ports/sysdeps/unix/sysv/linux/tile/setcontext.S new file mode 100644 index 0000000000..f95ad7ccaa --- /dev/null +++ b/ports/sysdeps/unix/sysv/linux/tile/setcontext.S @@ -0,0 +1,201 @@ +/* Copyright (C) 2011 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011. + + 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 <asm/errno.h> +#include <arch/spr_def.h> +#include <arch/abi.h> + +#include "ucontext_i.h" + +/* PL to return to via iret in setcontext */ +#define RETURN_PL 0 + +/* int setcontext (const ucontext_t *ucp) */ + + .text +ENTRY (__setcontext) + FEEDBACK_ENTER(__setcontext) + + /* See if this is a true signal context (flags == 0). + If so, restore by invoking rt_sigreturn(). */ +#if UC_FLAGS_OFFSET != 0 +# error "Add offset to r0 prior to load." +#endif + LD_PTR r10, r0 + { + BEQZ r10, .Lsigreturn + addi r10, r10, -1 /* Confirm that it has value "1". */ + } + BNEZ r10, .Lbadcontext + + /* Save lr and r0 briefly on the stack and set the signal mask: + rt_sigprocmask (SIG_SETMASK, &ucp->uc_sigmask, NULL, _NSIG / 8). */ + { + ST sp, lr + ADDI_PTR r11, sp, -(2 * REGSIZE) + move r10, sp + } + ADDI_PTR sp, sp, -(3 * REGSIZE) + cfi_def_cfa_offset (3 * REGSIZE) + cfi_offset (lr, 0) + { + ST r11, r10 + ADDI_PTR r10, sp, (2 * REGSIZE) + } + { + ST r10, r0 + ADDLI_PTR r1, r0, UC_SIGMASK_OFFSET + } + cfi_offset (r0, -REGSIZE) + { + movei r3, _NSIG / 8 + movei r2, 0 + } + { + movei r0, SIG_SETMASK + moveli TREG_SYSCALL_NR_NAME, __NR_rt_sigprocmask + } + swint1 + ADDI_PTR r11, sp, 2 * REGSIZE /* Restore uc_context to r11. */ + { + LD r11, r11 + ADDI_PTR sp, sp, 3 * REGSIZE + } + cfi_def_cfa_offset (0) + LD lr, sp + { + ADDI_PTR r10, r11, UC_REG(0) + BNEZ r1, .Lsyscall_error + } + + /* Restore the argument registers; note they will be random + unless makecontext() has been called. */ + { LD r0, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r1, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r2, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r3, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r4, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r5, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r6, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r7, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r8, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r9, r10; ADDLI_PTR r10, r10, UC_REG(30) - UC_REG(9) } + + /* Restore the callee-saved GPRs. */ + { LD r30, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r31, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r32, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r33, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r34, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r35, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r36, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r37, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r38, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r39, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r40, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r41, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r42, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r43, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r44, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r45, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r46, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r47, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r48, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r49, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r50, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r51, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r52, r10; ADDI_PTR r10, r10, REGSIZE * 2 } + /* Skip tp since it must not change for a given thread. */ + { LD sp, r10; ADDI_PTR r10, r10, REGSIZE } + { LD lr, r10; ADDI_PTR r10, r10, REGSIZE } + { LD r11, r10; ADDI_PTR r10, r10, REGSIZE } + + /* Construct an iret context; we set ICS so we can validly load + EX_CONTEXT for iret without being interrupted halfway through. */ + { + LD r12, r10 + movei r13, 1 + } + { + mtspr INTERRUPT_CRITICAL_SECTION, r13 + shli r12, r12, SPR_EX_CONTEXT_0_1__ICS_SHIFT + } + { + mtspr EX_CONTEXT_0_0, r11 + ori r12, r12, RETURN_PL + } + mtspr EX_CONTEXT_0_1, r12 + iret + jrp lr /* keep the backtracer happy */ + +.Lsigreturn: + /* This is a context obtained from a signal handler. + Perform a full restore by pushing the context + passed onto a simulated signal frame on the stack + and call the signal return syscall as if a signal + handler exited normally. */ + { + ADDLI_PTR sp, sp, -(C_ABI_SAVE_AREA_SIZE + SI_MAX_SIZE + UC_SIZE) + ADDLI_PTR r1, sp, -UC_SIZE + } + cfi_def_cfa_offset (C_ABI_SAVE_AREA_SIZE + SI_MAX_SIZE + UC_SIZE) + moveli r2, UC_SIZE / REGSIZE +0: { + LD r10, r0 + ADDI_PTR r0, r0, REGSIZE + } + { + ST r1, r10 + ADDI_PTR r1, r1, REGSIZE + addi r2, r2, -1 + } + BNEZ r2, 0b + moveli TREG_SYSCALL_NR_NAME, __NR_rt_sigreturn + swint1 + + /* Restore the stack and fall through to the error + path. Successful rt_sigreturn never returns to + its calling place. */ + ADDLI_PTR sp, sp, (C_ABI_SAVE_AREA_SIZE + SI_MAX_SIZE + UC_SIZE) + cfi_def_cfa_offset (0) + +.Lsyscall_error: + j SYSCALL_ERROR_NAME + +.Lbadcontext: + { + movei r1, EINVAL + j SYSCALL_ERROR_NAME + } + +END (__setcontext) + +.hidden __setcontext +weak_alias (__setcontext, setcontext) + +ENTRY (__startcontext) + FEEDBACK_ENTER(__startcontext) + BEQZ r30, 1f + { + move r0, r30 + jal __setcontext + } +1: j HIDDEN_JUMPTARGET(exit) +END (__startcontext) +.hidden __startcontext |