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glibc  2.9
__longjmp.c
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00001 /* Copyright (C) 1992, 1995, 1997, 2000, 2003, 2004
00002    Free Software Foundation, Inc.
00003    This file is part of the GNU C Library.
00004    Contributed by Brendan Kehoe (brendan@zen.org).
00005 
00006    The GNU C Library is free software; you can redistribute it and/or
00007    modify it under the terms of the GNU Lesser General Public
00008    License as published by the Free Software Foundation; either
00009    version 2.1 of the License, or (at your option) any later version.
00010 
00011    The GNU C Library is distributed in the hope that it will be useful,
00012    but WITHOUT ANY WARRANTY; without even the implied warranty of
00013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00014    Lesser General Public License for more details.
00015 
00016    You should have received a copy of the GNU Lesser General Public
00017    License along with the GNU C Library; if not, write to the Free
00018    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00019    02111-1307 USA.  */
00020 
00021 #include <setjmp.h>
00022 #include <sgidefs.h>
00023 #include <stdlib.h>
00024 
00025 #undef __longjmp
00026 
00027 #ifndef       __GNUC__
00028   #error This file uses GNU C extensions; you must compile with GCC.
00029 #endif
00030 
00031 void
00032 __longjmp (env, val_arg)
00033      __jmp_buf env;
00034      int val_arg;
00035 {
00036   /* gcc 1.39.19 miscompiled the longjmp routine (as it did setjmp before
00037      the hack around it); force it to use $a1 for the longjmp value.
00038      Without this it saves $a1 in a register which gets clobbered
00039      along the way.  */
00040   register int val asm ("a1");
00041 
00042 #ifdef __mips_hard_float
00043   /* Pull back the floating point callee-saved registers.  */
00044 #if _MIPS_SIM == _ABI64
00045   asm volatile ("l.d $f24, %0" : : "m" (env[0].__fpregs[0]));
00046   asm volatile ("l.d $f25, %0" : : "m" (env[0].__fpregs[1]));
00047   asm volatile ("l.d $f26, %0" : : "m" (env[0].__fpregs[2]));
00048   asm volatile ("l.d $f27, %0" : : "m" (env[0].__fpregs[3]));
00049   asm volatile ("l.d $f28, %0" : : "m" (env[0].__fpregs[4]));
00050   asm volatile ("l.d $f29, %0" : : "m" (env[0].__fpregs[5]));
00051   asm volatile ("l.d $f30, %0" : : "m" (env[0].__fpregs[6]));
00052   asm volatile ("l.d $f31, %0" : : "m" (env[0].__fpregs[7]));
00053 #else
00054   asm volatile ("l.d $f20, %0" : : "m" (env[0].__fpregs[0]));
00055   asm volatile ("l.d $f22, %0" : : "m" (env[0].__fpregs[1]));
00056   asm volatile ("l.d $f24, %0" : : "m" (env[0].__fpregs[2]));
00057   asm volatile ("l.d $f26, %0" : : "m" (env[0].__fpregs[3]));
00058   asm volatile ("l.d $f28, %0" : : "m" (env[0].__fpregs[4]));
00059   asm volatile ("l.d $f30, %0" : : "m" (env[0].__fpregs[5]));
00060 #endif
00061 
00062   /* Get and reconstruct the floating point csr.  */
00063   asm volatile ("lw $2, %0" : : "m" (env[0].__fpc_csr));
00064   asm volatile ("ctc1 $2, $31");
00065 #endif
00066 
00067   /* Get the GP. */
00068   asm volatile ("ld $gp, %0" : : "m" (env[0].__gp));
00069 
00070   /* Get the callee-saved registers.  */
00071   asm volatile ("ld $16, %0" : : "m" (env[0].__regs[0]));
00072   asm volatile ("ld $17, %0" : : "m" (env[0].__regs[1]));
00073   asm volatile ("ld $18, %0" : : "m" (env[0].__regs[2]));
00074   asm volatile ("ld $19, %0" : : "m" (env[0].__regs[3]));
00075   asm volatile ("ld $20, %0" : : "m" (env[0].__regs[4]));
00076   asm volatile ("ld $21, %0" : : "m" (env[0].__regs[5]));
00077   asm volatile ("ld $22, %0" : : "m" (env[0].__regs[6]));
00078   asm volatile ("ld $23, %0" : : "m" (env[0].__regs[7]));
00079 
00080   /* Get the PC.  */
00081   asm volatile ("ld $31, %0" : : "m" (env[0].__pc));
00082 
00083 
00084   /* Restore the stack pointer and the FP.  They have to be restored
00085      last and in a single asm as gcc, depending on options used, may
00086      use either of them to access env.  */
00087   asm volatile ("ld $29, %0\n\t"
00088               "ld $30, %1\n\t" : : "m" (env[0].__sp), "m" (env[0].__fp));
00089 
00090 /* Give setjmp 1 if given a 0, or what they gave us if non-zero.  */
00091   if (val == 0)
00092     asm volatile ("dli $2, 1");
00093   else
00094     asm volatile ("move $2, %0" : : "r" (val));
00095 
00096   asm volatile ("j $31");
00097 
00098   /* Avoid `volatile function does return' warnings.  */
00099   for (;;);
00100 }