diff options
Diffstat (limited to 'src/thread_asm.S')
-rw-r--r-- | src/thread_asm.S | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/src/thread_asm.S b/src/thread_asm.S new file mode 100644 index 0000000..0327fce --- /dev/null +++ b/src/thread_asm.S @@ -0,0 +1,51 @@ +/* + * Copyright (c) 2017 Richard Braun. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ + +.section .text +.code32 + +.global thread_load_context +thread_load_context: + mov 4(%esp), %eax /* Load the thread address */ + mov (%eax), %esp /* Switch to the thread stack */ + jmp thread_restore_context + +.global thread_switch_context +thread_switch_context: + mov 4(%esp), %eax /* Get prev thread address */ + mov 8(%esp), %ecx /* Get next thread address */ + + push %ebp /* Save registers owned by the caller */ + push %ebx + push %edi + push %esi + + mov %esp, (%eax) /* Save prev thread stack pointer */ + mov (%ecx), %esp /* Switch to the stack of the next thread */ + +thread_restore_context: + pop %esi + pop %edi + pop %ebx + pop %ebp + + ret |