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.global handle_cycle_limit
.global do_sync
handle_cycle_limit:
cmp 84(%rsi), %eax
jb skip_sync
do_sync:
push %rcx
push %rdi
call m68k_save_context
mov %rsi, %rdi
xor %esi, %esi
test $8, %esp
jnz adjust_rsp
call sync_components
jmp done_adjust
adjust_rsp:
sub $8, %rsp
call sync_components
add $8, %rsp
done_adjust:
mov %rax, %rsi
call m68k_load_context
pop %rdi
pop %rcx
skip_sync:
ret
sr_msg_int:
.asciz "SR set to $%X due to interrupt\n"
debug_print_sr_int:
call m68k_save_context
push %rsi
lea sr_msg_int(%rip), %rdi
movzxb 5(%rsi), %rsi
xor %rax, %rax
call printf
pop %rsi
call m68k_load_context
ret
sr_msg:
.asciz "SR set to $%X\n"
.global debug_print_sr
debug_print_sr:
call m68k_save_context
push %rsi
lea sr_msg(%rip), %rdi
movzxb 5(%rsi), %rsi
xor %rax, %rax
call printf
pop %rsi
call m68k_load_context
ret
invalid_msg:
.asciz "Invalid instruction at %X\n"
.global m68k_invalid
m68k_invalid:
lea invalid_msg(%rip), %rdi
mov %ecx, %esi
xor %rax, %rax
call printf
mov $1, %rdi
call exit
.global bcd_add
bcd_add:
xchg %rax, %rdi
mov %cl, %ch
mov %al, %ah
and $0xF, %ch
and $0xF, %ah
and $0xF0, %cl
and $0xF0, %al
add %ah, %ch
cmp $10, %ch
jb no_adjust
add $6, %ch
no_adjust:
add %ch, %al
add %al, %cl
mov $0, %ch
jc def_adjust
cmp $0xA0, %cl
jb no_adjust_h
def_adjust:
add $0x60, %cl
mov $1, %ch
no_adjust_h:
mov %rdi, %rax
ret
.global bcd_sub
bcd_sub:
xchg %rax, %rdi
mov %cl, %ch
mov %al, %ah
and $0xF, %ch
and $0xF, %ah
and $0xF0, %cl
and $0xF0, %al
sub %ah, %ch
cmp $10, %ch
jb no_adjusts
sub $6, %ch
no_adjusts:
add %ch, %cl
sub %al, %cl
mov $0, %ch
jc def_adjusts
cmp $0xA0, %cl
jb no_adjust_hs
def_adjusts:
sub $0x60, %cl
mov $1, %ch
no_adjust_hs:
mov %rdi, %rax
ret
.global get_sr
get_sr:
mov 5(%rsi), %cl
shl $8, %cx
mov (%rsi), %cl
shl $1, %cl
or %bl, %cl
shl $1, %cl
or %dl, %cl
shl $1, %cl
or %bh, %cl
shl $1, %cl
or %dh, %cl
ret
.global set_sr
set_sr:
mov %cl, %dh
and $1, %dh
shr $1, %cl
mov %cl, %bh
and $1, %bh
shr $1, %cl
mov %cl, %dl
and $1, %dl
shr $1, %cl
mov %cl, %bl
and $1, %bl
shr $1, %cl
and $1, %cl
mov %cl, (%rsi)
shr $8, %cx
mov %cl, 5(%rsi)
/* call debug_print_sr */
ret
.global set_ccr
set_ccr:
mov %cl, %dh
and $1, %dh
shr $1, %cl
mov %cl, %bh
and $1, %bh
shr $1, %cl
mov %cl, %dl
and $1, %dl
shr $1, %cl
mov %cl, %bl
and $1, %bl
shr $1, %cl
and $1, %cl
mov %cl, (%rsi)
ret
.global m68k_modified_ret_addr
m68k_modified_ret_addr:
add $16, %rsp
call m68k_native_addr
jmp *%rcx
.global m68k_native_addr_and_sync
m68k_native_addr_and_sync:
call m68k_save_context
push %rcx
mov %rsi, %rdi
xor %esi, %esi
test $8, %rsp
jnz adjust_rsp_na
call sync_components
jmp no_adjust_rsp_na
adjust_rsp_na:
sub $8, %rsp
call sync_components
add $8, %rsp
no_adjust_rsp_na:
pop %rsi
push %rax
mov %rax, %rdi
call get_native_address_trans
mov %rax, %rcx
pop %rsi
call m68k_load_context
ret
.global m68k_native_addr
m68k_native_addr:
call m68k_save_context
push %rsi
mov %rsi, %rdi
mov %ecx, %esi
call get_native_address_trans
mov %rax, %rcx
pop %rsi
call m68k_load_context
ret
.global m68k_retrans_stub
m68k_retrans_stub:
call m68k_save_context
push %rsi
call m68k_retranslate_inst
pop %rsi
mov %rax, %rcx
call m68k_load_context
jmp *%rcx
.global m68k_save_context
m68k_save_context:
mov %bl, 1(%rsi) /* N Flag */
mov %dl, 2(%rsi) /* Z flag */
mov %bh, 3(%rsi) /* V flag */
mov %dh, 4(%rsi) /* C flag */
mov %r10d, 8(%rsi) /* d0 */
mov %r11d, 12(%rsi) /* d1 */
mov %r12d, 16(%rsi) /* d2 */
mov %r8d, 20(%rsi) /* d3 */
mov %r13d, 40(%rsi) /* a0 */
mov %r14d, 44(%rsi) /* a1 */
mov %r9d, 48(%rsi) /* a2 */
mov %r15d, 68(%rsi) /* a7 */
mov %eax, 80(%rsi) /* current cycle count */
ret
.global m68k_load_context
m68k_load_context:
mov 1(%rsi), %bl /* N Flag */
mov 2(%rsi), %dl /* Z flag */
mov 3(%rsi), %bh /* V flag */
mov 4(%rsi), %dh /* C flag */
mov 8(%rsi), %r10d /* d0 */
mov 12(%rsi), %r11d /* d1 */
mov 16(%rsi), %r12d /* d2 */
mov 20(%rsi), %r8d /* d3 */
mov 40(%rsi), %r13d /* a0 */
mov 44(%rsi), %r14d /* a1 */
mov 48(%rsi), %r9d /* a2 */
mov 68(%rsi), %r15d /* a7 */
mov 76(%rsi), %ebp /* target cycle count */
mov 80(%rsi), %eax /* current cycle count */
ret
.global m68k_start_context
m68k_start_context:
push %rbp
push %r12
push %r13
push %r14
push %r15
call m68k_load_context
call *%rdi
call m68k_save_context
pop %r15
pop %r14
pop %r13
pop %r12
pop %rbp
ret
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