Home | History | Annotate | Line # | Download | only in mips 
      1 /* MIPS support code for fibers and multithreading.
      2    Copyright (C) 2019-2022 Free Software Foundation, Inc.
      3 
      4 This file is part of GCC.
      5 
      6 GCC is free software; you can redistribute it and/or modify it under
      7 the terms of the GNU General Public License as published by the Free
      8 Software Foundation; either version 3, or (at your option) any later
      9 version.
     10 
     11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
     12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
     13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
     14 for more details.
     15 
     16 Under Section 7 of GPL version 3, you are granted additional
     17 permissions described in the GCC Runtime Library Exception, version
     18 3.1, as published by the Free Software Foundation.
     19 
     20 You should have received a copy of the GNU General Public License and
     21 a copy of the GCC Runtime Library Exception along with this program;
     22 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
     23 <http://www.gnu.org/licenses/>.  */
     24 
     25 #include "../common/threadasm.S"
     26 
     27 #if _MIPS_SIM == _ABIO32
     28 
     29 /**
     30  * Performs a context switch.
     31  *
     32  * $a0 - void** - ptr to old stack pointer
     33  * $a1 - void*  - new stack pointer
     34  *
     35  */
     36     .text
     37     .globl fiber_switchContext
     38     .align 2
     39     .ent fiber_switchContext,0
     40 fiber_switchContext:
     41     .cfi_startproc
     42     addiu $sp, $sp, -(10 * 4)
     43 
     44     // fp regs and return address are stored below the stack
     45     // because we don't want the GC to scan them.
     46 
     47 #ifdef __mips_hard_float
     48 #define ALIGN8(val) (val + (-val & 7))
     49 #define BELOW (ALIGN8(6 * 8 + 4))
     50     s.d $f20, (0 * 8 - BELOW)($sp)
     51     s.d $f22, (1 * 8 - BELOW)($sp)
     52     s.d $f24, (2 * 8 - BELOW)($sp)
     53     s.d $f26, (3 * 8 - BELOW)($sp)
     54     s.d $f28, (4 * 8 - BELOW)($sp)
     55     s.d $f30, (5 * 8 - BELOW)($sp)
     56 #endif
     57     sw $ra, -4($sp)
     58 
     59     sw $s0, (0 * 4)($sp)
     60     sw $s1, (1 * 4)($sp)
     61     sw $s2, (2 * 4)($sp)
     62     sw $s3, (3 * 4)($sp)
     63     sw $s4, (4 * 4)($sp)
     64     sw $s5, (5 * 4)($sp)
     65     sw $s6, (6 * 4)($sp)
     66     sw $s7, (7 * 4)($sp)
     67     sw $s8, (8 * 4)($sp)
     68     sw $gp, (9 * 4)($sp)
     69 
     70     // swap stack pointer
     71     sw $sp, 0($a0)
     72     move $sp, $a1
     73 
     74 #ifdef __mips_hard_float
     75     l.d $f20, (0 * 8 - BELOW)($sp)
     76     l.d $f22, (1 * 8 - BELOW)($sp)
     77     l.d $f24, (2 * 8 - BELOW)($sp)
     78     l.d $f26, (3 * 8 - BELOW)($sp)
     79     l.d $f28, (4 * 8 - BELOW)($sp)
     80     l.d $f30, (5 * 8 - BELOW)($sp)
     81 #endif
     82     lw $ra, -4($sp)
     83 
     84     lw $s0, (0 * 4)($sp)
     85     lw $s1, (1 * 4)($sp)
     86     lw $s2, (2 * 4)($sp)
     87     lw $s3, (3 * 4)($sp)
     88     lw $s4, (4 * 4)($sp)
     89     lw $s5, (5 * 4)($sp)
     90     lw $s6, (6 * 4)($sp)
     91     lw $s7, (7 * 4)($sp)
     92     lw $s8, (8 * 4)($sp)
     93     lw $gp, (9 * 4)($sp)
     94 
     95     addiu $sp, $sp, (10 * 4)
     96 
     97     jr $ra // return
     98     .cfi_endproc
     99     .end fiber_switchContext
    100     .size fiber_switchContext,.-fiber_switchContext
    101 
    102 #endif
    103