.text
   .globl swi_handler
   .type swi_handler,@function
swi_handler:
   movq %rdx, amd64_spill_rdx(%rip)
   movq %rdi, amd64_spill_rdi(%rip)
   movq %rsi, amd64_spill_rsi(%rip)

   cmpq $0, %rcx
   jl swi_kernel

   movq dcb_current(%rip), %rdx
   movq 8(%rdx), %rdx

   cmpb $0, 0(%rdx)
   ja disabled

   cmpq 96(%rdx), %rcx
   jc enabled

   cmpq 104(%rdx), %rcx
   jc disabled

enabled:
   leaq 112(%rdx), %rdi
   movq $0x0000000000000000, %rsi
   jmp checked

disabled:
   movq $0x0000000000000001, %rsi
   leaq 440(%rdx), %rdi

checked:
   movq %rax, RAX_REG(%rdi)
   movq %rbx, RBX_REG(%rdi)
   movq %rcx, RCX_REG(%rdi)
   movq %rbp, RBP_REG(%rdi)
   movq %rsp, RSP_REG(%rdi)
   movq %r8, R8_REG(%rdi)
   movq %r9, R9_REG(%rdi)
   movq %r10, R10_REG(%rdi)
   movq %r11, R11_REG(%rdi)
   movq %r12, R12_REG(%rdi)
   movq %r13, R13_REG(%rdi)
   movq %r14, R14_REG(%rdi)
   movq %r15, R15_REG(%rdi)
   mov %cr2, %rax
   mov %rax, CR2_REG(%rdi)
   movq (amd64_spillarea + OFFSETOF_SPILLAREA_RDI)(%rip), %rax
   movq (amd64_spillarea + OFFSETOF_SPILLAREA_RSI)(%rip), %rbx
   movq (amd64_spillarea + OFFSETOF_SPILLAREA_RDX)(%rip), %rcx
   movq %rax, RDI_REG(%rdi)
   movq %rbx, RSI_REG(%rdi)
   movq %rcx, RDX_REG(%rdi)

   leaq kernel_stack(%rip), %rsp
   subq $0xfffffffffffff000, %rsp
   jmp sys_syscall@PLT

swi_kernel:
   jmp sys_syscall_kernel@PLT
   .size swi_handler, . - swi_handler