sysdeps/mips/mips64/__longjmp.c

   1 /* Copyright (C) 1992-2022 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 #include <stdlib.h>
  21
  22 #ifndef __GNUC__
  23   #error This file uses GNU C extensions; you must compile with GCC.
  24 #endif
  25
  26 void
  27 __longjmp (__jmp_buf env_arg, int val_arg)
  28 {
  29   /* gcc 1.39.19 miscompiled the longjmp routine (as it did setjmp before
  30      the hack around it); force it to use $a1 for the longjmp value.
  31      Without this it saves $a1 in a register which gets clobbered
  32      along the way.  */
  33   register struct __jmp_buf_internal_tag *env asm ("a0");
  34   register int val asm ("a1");
  35 #ifdef CHECK_SP
  36   register long long sp asm ("$29");
  37   CHECK_SP (env[0].__sp, sp, long long);
  38 #endif
  39
  40 #ifdef __mips_hard_float
  41   /* Pull back the floating point callee-saved registers.  */
  42 #if _MIPS_SIM == _ABI64
  43   asm volatile ("l.d $f24, %0" : : "m" (env[0].__fpregs[0]));
  44   asm volatile ("l.d $f25, %0" : : "m" (env[0].__fpregs[1]));
  45   asm volatile ("l.d $f26, %0" : : "m" (env[0].__fpregs[2]));
  46   asm volatile ("l.d $f27, %0" : : "m" (env[0].__fpregs[3]));
  47   asm volatile ("l.d $f28, %0" : : "m" (env[0].__fpregs[4]));
  48   asm volatile ("l.d $f29, %0" : : "m" (env[0].__fpregs[5]));
  49   asm volatile ("l.d $f30, %0" : : "m" (env[0].__fpregs[6]));
  50   asm volatile ("l.d $f31, %0" : : "m" (env[0].__fpregs[7]));
  51 #else
  52   asm volatile ("l.d $f20, %0" : : "m" (env[0].__fpregs[0]));
  53   asm volatile ("l.d $f22, %0" : : "m" (env[0].__fpregs[1]));
  54   asm volatile ("l.d $f24, %0" : : "m" (env[0].__fpregs[2]));
  55   asm volatile ("l.d $f26, %0" : : "m" (env[0].__fpregs[3]));
  56   asm volatile ("l.d $f28, %0" : : "m" (env[0].__fpregs[4]));
  57   asm volatile ("l.d $f30, %0" : : "m" (env[0].__fpregs[5]));
  58 #endif
  59 #endif
  60
  61   /* Get the GP. */
  62   asm volatile ("ld $gp, %0" : : "m" (env[0].__gp));
  63
  64   /* Get the callee-saved registers.  */
  65   asm volatile ("ld $16, %0" : : "m" (env[0].__regs[0]));
  66   asm volatile ("ld $17, %0" : : "m" (env[0].__regs[1]));
  67   asm volatile ("ld $18, %0" : : "m" (env[0].__regs[2]));
  68   asm volatile ("ld $19, %0" : : "m" (env[0].__regs[3]));
  69   asm volatile ("ld $20, %0" : : "m" (env[0].__regs[4]));
  70   asm volatile ("ld $21, %0" : : "m" (env[0].__regs[5]));
  71   asm volatile ("ld $22, %0" : : "m" (env[0].__regs[6]));
  72   asm volatile ("ld $23, %0" : : "m" (env[0].__regs[7]));
  73
  74   /* Get the PC.  */
  75   asm volatile ("ld $31, %0" : : "m" (env[0].__pc));
  76
  77
  78   /* Restore the stack pointer and the FP.  They have to be restored
  79      last and in a single asm as gcc, depending on options used, may
  80      use either of them to access env.  */
  81   asm volatile ("ld $29, %0\n\t"
  82                 "ld $30, %1\n\t" : : "m" (env[0].__sp), "m" (env[0].__fp));
  83
  84 /* Give setjmp 1 if given a 0, or what they gave us if non-zero.  */
  85   if (val == 0)
  86     asm volatile ("dli $2, 1");
  87   else
  88     asm volatile ("move $2, %0" : : "r" (val));
  89
  90   asm volatile ("j $31");
  91
  92   /* Avoid `volatile function does return' warnings.  */
  93   for (;;);
  94 }