.file "fiber_continue_x86_64.s" .text .global __fiber_continue .type __fiber_continue, @function .align 16 __fiber_continue: # Parameter List (in order) # rdi = pointer to continuation (should hold value of target stack will be filled with this continuation) # Return # rax = continuation that returned control back to the caller (null if fallthrough) # Variables # r12 = temporary for the old stack pointer ############### Save State ############### # Make space for all register state we will store. leaq -0x38(%rsp), %rsp # Store calee saved general registers. movq %r12, 0x00(%rsp) movq %r13, 0x08(%rsp) movq %r14, 0x10(%rsp) movq %r15, 0x18(%rsp) movq %rbx, 0x20(%rsp) movq %rbp, 0x28(%rsp) # Store MMX control- and status-word stmxcsr 0x30(%rsp) # Store x87 control-word fnstcw 0x34(%rsp) ############### Save State ############### # Perform change to new stack. # Keep old stack as second parameter to our callback function. movq %rsp, %r12 # switch to new stack pointer movq %rdi, %rsp ############ Restore State ############ # restore calee saved general registers movq 0x00(%rsp), %r12 movq 0x08(%rsp), %r13 movq 0x10(%rsp), %r14 movq 0x18(%rsp), %r15 movq 0x20(%rsp), %rbx movq 0x28(%rsp), %rbp # restore MMX control- and status-word ldmxcsr 0x30(%rsp) # restore x87 control-word fldcw 0x34(%rsp) # Free space for restored state leaq 0x38(%rsp), %rsp ############ Restore State ############ # Return the context we came from as a continuation. movq %r12, %rax ret