X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Fthreads%2Fswitch.S;h=6cb70aa86e38b8ad85c930376e260ce7ef43cf1d;hb=441c95fdb9ead6e5575c3e720b47df6c20e179d2;hp=4f0d412c7266e3117d6fa33bdb2e9f598dbb63e8;hpb=5b670fb86ef37f5a81188e940e5fe1b04b5824af;p=pintos-anon diff --git a/src/threads/switch.S b/src/threads/switch.S index 4f0d412..6cb70aa 100644 --- a/src/threads/switch.S +++ b/src/threads/switch.S @@ -12,54 +12,56 @@ #### restore the registers. As part of switching stacks we record the #### current stack pointer in CUR's thread structure. - .intel_syntax noprefix - -.globl switch_threads +.globl switch_threads +.func switch_threads switch_threads: # Save caller's register state. # - # Note that the SVR4 ABI allows us to destroy eax, ecx, edx, - # but requires us to preserve ebx, ebp, esi, edi. See + # Note that the SVR4 ABI allows us to destroy %eax, %ecx, %edx, + # but requires us to preserve %ebx, %ebp, %esi, %edi. See # [SysV-ABI-386] pages 3-11 and 3-12 for details. # # This stack frame must match the one set up by thread_create(). - push ebx - push ebp - push esi - push edi + pushl %ebx + pushl %ebp + pushl %esi + pushl %edi # Get offsetof (struct thread, stack). .globl thread_stack_ofs - mov edx, thread_stack_ofs + mov thread_stack_ofs, %edx # Save current stack pointer to old thread's stack, if any. - mov eax, SWITCH_CUR[esp] - test eax, eax + movl SWITCH_CUR(%esp), %eax + test %eax, %eax jz 1f - mov [eax + edx], esp + movl %esp, (%eax,%edx,1) 1: # Restore stack pointer from new thread's stack. - mov ecx, SWITCH_NEXT[esp] - mov esp, [ecx + edx] + movl SWITCH_NEXT(%esp), %ecx + movl (%ecx,%edx,1), %esp # Restore caller's register state. - pop edi - pop esi - pop ebp - pop ebx + popl %edi + popl %esi + popl %ebp + popl %ebx ret +.endfunc .globl switch_entry +.func switch_entry switch_entry: # Discard switch_threads() arguments. - add esp, 8 + addl $8, %esp # Call schedule_tail(prev). - push eax + pushl %eax .globl schedule_tail call schedule_tail - add esp, 4 + addl $4, %esp # Start thread proper. ret +.endfunc