sysdeps/mips/mips64/setjmp_aux.c

   1 /* Copyright (C) 1996-2023 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library.  If not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <setjmp.h>
  19 #include <sgidefs.h>
  20
  21 /* This function is only called via the assembly language routine
  22    __sigsetjmp, which arranges to pass in the stack pointer and the frame
  23    pointer.  We do things this way because it's difficult to reliably
  24    access them in C.  */
  25
  26 /* Stack protection is disabled to avoid changing s0 (or any other
  27    caller-save register) before storing it to environment.
  28    See BZ #22624.  */
  29
  30 int
  31 inhibit_stack_protector
  32 __sigsetjmp_aux (jmp_buf env, int savemask, long long sp, long long fp,
  33                  long long gp)
  34 {
  35 #ifdef __mips_hard_float
  36   /* Store the floating point callee-saved registers...  */
  37 #if _MIPS_SIM == _ABI64
  38   asm volatile ("s.d $f24, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[0]));
  39   asm volatile ("s.d $f25, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[1]));
  40   asm volatile ("s.d $f26, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[2]));
  41   asm volatile ("s.d $f27, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[3]));
  42   asm volatile ("s.d $f28, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[4]));
  43   asm volatile ("s.d $f29, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[5]));
  44   asm volatile ("s.d $f30, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[6]));
  45   asm volatile ("s.d $f31, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[7]));
  46 #else
  47   asm volatile ("s.d $f20, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[0]));
  48   asm volatile ("s.d $f22, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[1]));
  49   asm volatile ("s.d $f24, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[2]));
  50   asm volatile ("s.d $f26, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[3]));
  51   asm volatile ("s.d $f28, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[4]));
  52   asm volatile ("s.d $f30, %0" : : "m" (env[0].__jmpbuf[0].__fpregs[5]));
  53 #endif
  54 #endif
  55
  56   /* .. and the PC;  */
  57   asm volatile ("sd $31, %0" : : "m" (env[0].__jmpbuf[0].__pc));
  58
  59   /* .. and the stack pointer;  */
  60   env[0].__jmpbuf[0].__sp = sp;
  61
  62   /* .. and the FP; it'll be in s8. */
  63   env[0].__jmpbuf[0].__fp = fp;
  64
  65   /* .. and the GP; */
  66   env[0].__jmpbuf[0].__gp = gp;
  67
  68   /* .. and the callee-saved registers; */
  69   asm volatile ("sd $16, %0" : : "m" (env[0].__jmpbuf[0].__regs[0]));
  70   asm volatile ("sd $17, %0" : : "m" (env[0].__jmpbuf[0].__regs[1]));
  71   asm volatile ("sd $18, %0" : : "m" (env[0].__jmpbuf[0].__regs[2]));
  72   asm volatile ("sd $19, %0" : : "m" (env[0].__jmpbuf[0].__regs[3]));
  73   asm volatile ("sd $20, %0" : : "m" (env[0].__jmpbuf[0].__regs[4]));
  74   asm volatile ("sd $21, %0" : : "m" (env[0].__jmpbuf[0].__regs[5]));
  75   asm volatile ("sd $22, %0" : : "m" (env[0].__jmpbuf[0].__regs[6]));
  76   asm volatile ("sd $23, %0" : : "m" (env[0].__jmpbuf[0].__regs[7]));
  77
  78   /* Save the signal mask if requested.  */
  79   return __sigjmp_save (env, savemask);
  80 }