expressi.inc

一个用纯汇编 写的操作系统 源代码 是用 TASM 编译器写的

	ret
      fp_div:
	mov	eax,[edi+4]
	xor	edx,edx
	div	ecx
	mov	[edi+4],eax
	mov	eax,[edi]
	div	ecx
	mov	[edi],eax
	mov	eax,[edi+12]
	div	ecx
	mov	[edi+12],eax
	mov	ebx,eax
	or	ebx,[edi]
	or	ebx,[edi+4]
	jz	fp_zero
      .loop:
	test	byte [edi+7],80h
	jnz	.exp_ok
	mov	eax,[edi]
	shld	[edi+4],eax,1
	mov	eax,[edi+12]
	shld	[edi],eax,1
	add	eax,eax
	mov	[edi+12],eax
	dec	dword [edi+8]
	add	edx,edx
	jmp	.loop
      .exp_ok:
	mov	eax,edx
	xor	edx,edx
	div	ecx
	add	[edi+12],eax
	adc	dword [edi],0
	adc	dword [edi+4],0
	jnc	.done
	mov	eax,[edi+4]
	mov	ebx,[edi]
	shrd	[edi],eax,1
	shrd	[edi+12],ebx,1
	shr	eax,1
	or	eax,80000000h
	mov	[edi+4],eax
	inc	dword [edi+8]
      .done:
	ret
      fp_add:
	cmp	dword [ebx+8],8000h
	je	.done
	cmp	dword [edi+8],8000h
	je	.copy
	mov	eax,[ebx+8]
	cmp	eax,[edi+8]
	jge	.exp_ok
	mov	eax,[edi+8]
      .exp_ok:
	call	.change_exp
	xchg	ebx,edi
	call	.change_exp
	xchg	ebx,edi
	mov	edx,[ebx+12]
	mov	eax,[ebx]
	mov	ebx,[ebx+4]
	add	[edi+12],edx
	adc	[edi],eax
	adc	[edi+4],ebx
	jnc	.done
	mov	eax,[edi]
	shrd	[edi+12],eax,1
	mov	eax,[edi+4]
	shrd	[edi],eax,1
	shr	eax,1
	or	eax,80000000h
	mov	[edi+4],eax
	inc	dword [edi+8]
      .done:
	ret
      .copy:
	mov	eax,[ebx]
	mov	[edi],eax
	mov	eax,[ebx+4]
	mov	[edi+4],eax
	mov	eax,[ebx+8]
	mov	[edi+8],eax
	mov	eax,[ebx+12]
	mov	[edi+12],eax
	ret
      .change_exp:
	push	ecx
	mov	ecx,eax
	sub	ecx,[ebx+8]
	mov	edx,[ebx+4]
	jecxz	.exp_done
      .exp_loop:
	mov	ebp,[ebx]
	shrd	[ebx+12],ebp,1
	shrd	[ebx],edx,1
	shr	edx,1
	inc	dword [ebx+8]
	loop	.exp_loop
      .exp_done:
	mov	[ebx+4],edx
	pop	ecx
	ret
      fp_optimize:
	mov	eax,[edi]
	mov	ebp,[edi+4]
	or	ebp,[edi]
	or	ebp,[edi+12]
	jz	fp_zero
      .loop:
	test	byte [edi+7],80h
	jnz	.done
	shld	[edi+4],eax,1
	mov	ebp,[edi+12]
	shld	eax,ebp,1
	mov	[edi],eax
	shl	dword [edi+12],1
	dec	dword [edi+8]
	jmp	.loop
      .done:
	ret
      fp_zero:
	mov	dword [edi+8],8000h
	ret

calculate_expression:
	mov	[current_offset],edi
	mov	[value_undefined],0
	cmp	byte [esi],0
	je	get_string_value
	cmp	byte [esi],'.'
	je	convert_fp
      calculation_loop:
	lods	byte [esi]
	cmp	al,1
	je	get_byte_number
	cmp	al,2
	je	get_word_number
	cmp	al,4
	je	get_dword_number
	cmp	al,8
	je	get_qword_number
	cmp	al,0Fh
	je	value_out_of_range
	cmp	al,10h
	je	get_register
	cmp	al,11h
	je	get_label
	cmp	al,')'
	je	expression_calculated
	cmp	al,']'
	je	expression_calculated
	cmp	al,'!'
	je	invalid_expression
	sub	edi,14h
	mov	ebx,edi
	sub	ebx,14h
	cmp	al,0E0h
	je	calculate_rva
	cmp	al,0E1h
	je	calculate_plt
	cmp	al,0D0h
	je	calculate_not
	cmp	al,083h
	je	calculate_neg
	mov	dx,[ebx+8]
	or	dx,[edi+8]
	cmp	al,80h
	je	calculate_add
	cmp	al,81h
	je	calculate_sub
	mov	ah,[ebx+12]
	or	ah,[edi+12]
	jz	absolute_values_calculation
	cmp	[error_line],0
	jne	absolute_values_calculation
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      absolute_values_calculation:
	cmp	al,90h
	je	calculate_mul
	cmp	al,91h
	je	calculate_div
	or	dx,dx
	jnz	invalid_expression
	cmp	al,0A0h
	je	calculate_mod
	cmp	al,0B0h
	je	calculate_and
	cmp	al,0B1h
	je	calculate_or
	cmp	al,0B2h
	je	calculate_xor
	cmp	al,0C0h
	je	calculate_shl
	cmp	al,0C1h
	je	calculate_shr
	jmp	invalid_expression
      expression_calculated:
	sub	edi,14h
	cmp	[value_undefined],0
	je	expression_value_ok
	xor	eax,eax
	mov	[edi],eax
	mov	[edi+4],eax
	mov	[edi+12],al
      expression_value_ok:
	ret
      get_byte_number:
	mov	word [edi+8],0
	mov	byte [edi+12],0
	xor	eax,eax
	lods	byte [esi]
	stos	dword [edi]
	xor	al,al
	stos	dword [edi]
	add	edi,0Ch
	jmp	calculation_loop
      get_word_number:
	mov	word [edi+8],0
	mov	byte [edi+12],0
	xor	eax,eax
	lods	word [esi]
	stos	dword [edi]
	xor	ax,ax
	stos	dword [edi]
	add	edi,0Ch
	jmp	calculation_loop
      get_dword_number:
	mov	word [edi+8],0
	mov	byte [edi+12],0
	movs	dword [edi],[esi]
	xor	eax,eax
	stos	dword [edi]
	add	edi,0Ch
	jmp	calculation_loop
      get_qword_number:
	mov	word [edi+8],0
	mov	byte [edi+12],0
	movs	dword [edi],[esi]
	movs	dword [edi],[esi]
	add	edi,0Ch
	jmp	calculation_loop
      get_register:
	mov	byte [edi+9],0
	mov	byte [edi+12],0
	lods	byte [esi]
	mov	[edi+8],al
	mov	byte [edi+10],1
	xor	eax,eax
	stos	dword [edi]
	stos	dword [edi]
	add	edi,0Ch
	jmp	calculation_loop
      get_label:
	xor	eax,eax
	mov	[edi+8],eax
	mov	[edi+12],al
	mov	[edi+20],eax
	lods	dword [esi]
	cmp	eax,0Fh
	jb	predefined_label
	je	reserved_word_used_as_symbol
	mov	ebx,eax
	mov	ax,[current_pass]
	mov	[ebx+18],ax
	or	byte [ebx+8],8
	test	byte [ebx+8],1
	jz	label_undefined
	cmp	ax,[ebx+16]
	je	label_defined
	test	byte [ebx+8],4
	jnz	label_undefined
	test	byte [ebx+9],1
	jz	label_defined
	mov	eax,[ebx]
	sub	eax,dword [adjustment]
	stos	dword [edi]
	mov	eax,[ebx+4]
	sbb	eax,dword [adjustment+4]
	stos	dword [edi]
	mov	eax,dword [adjustment]
	or	eax,dword [adjustment+4]
	jz	got_label
	or	[next_pass_needed],-1
	jmp	got_label
      label_defined:
	mov	eax,[ebx]
	stos	dword [edi]
	mov	eax,[ebx+4]
	stos	dword [edi]
      got_label:
	mov	al,[ebx+11]
	mov	[edi-8+12],al
	mov	eax,[ebx+12]
	mov	[edi-8+8],eax
	mov	eax,[ebx+20]
	mov	[edi-8+16],eax
	add	edi,0Ch
	mov	al,[ebx+10]
	or	al,al
	jz	calculation_loop
	cmp	[size_override],-1
	je	calculation_loop
	cmp	[size_override],0
	je	check_size
	cmp	[operand_size],0
	jne	calculation_loop
	mov	[operand_size],al
	jmp	calculation_loop
      check_size:
	xchg	[operand_size],al
	or	al,al
	jz	calculation_loop
	cmp	al,[operand_size]
	jne	operand_sizes_do_not_match
	jmp	calculation_loop
      current_offset_label:
	mov	al,[labels_type]
	mov	[edi+12],al
	mov	eax,[org_symbol]
	mov	[edi+16],eax
	mov	eax,[current_offset]
	xor	edx,edx
	sub	eax,dword [org_origin]
	sbb	edx,dword [org_origin+4]
	stos	dword [edi]
	mov	eax,edx
	stos	dword [edi]
	mov	eax,[org_registers]
	stos	dword [edi]
	add	edi,8
	jmp	calculation_loop
      org_origin_label:
	mov	al,[labels_type]
	mov	[edi+12],al
	mov	eax,[org_symbol]
	mov	[edi+16],eax
	mov	eax,[org_start]
	xor	edx,edx
	sub	eax,dword [org_origin]
	sbb	edx,dword [org_origin+4]
	stos	dword [edi]
	mov	eax,edx
	stos	dword [edi]
	mov	eax,[org_registers]
	stos	dword [edi]
	add	edi,8
	jmp	calculation_loop
      counter_label:
	mov	eax,[counter]
      make_dword_label_value:
	stos	dword [edi]
	xor	eax,eax
	stos	dword [edi]
	add	edi,0Ch
	jmp	calculation_loop
      timestamp_label:
	call	make_timestamp
	jmp	make_dword_label_value
      predefined_label:
	or	eax,eax
	jz	current_offset_label
	cmp	eax,1
	je	counter_label
	cmp	eax,2
	je	timestamp_label
	cmp	eax,3
	je	org_origin_label
      label_undefined:
	cmp	[current_pass],1
	ja	undefined_value
      force_next_pass:
	or	[next_pass_needed],-1
      undefined_value:
	mov	byte [edi+12],0
	or	[value_undefined],-1
	xor	eax,eax
	stos	dword [edi]
	stos	dword [edi]
	add	edi,0Ch
	cmp	[error_line],0
	jne	calculation_loop
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],undefined_symbol
	jmp	calculation_loop
      calculate_add:
	mov	ecx,[ebx+16]
	cmp	byte [edi+12],0
	je	add_values
	mov	ecx,[edi+16]
	cmp	byte [ebx+12],0
	je	add_values
	cmp	[error_line],0
	jne	add_values
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      add_values:
	mov	al,[edi+12]
	or	[ebx+12],al
	mov	[ebx+16],ecx
	mov	eax,[edi]
	add	[ebx],eax
	mov	eax,[edi+4]
	adc	[ebx+4],eax
	or	dx,dx
	jz	calculation_loop
	push	esi
	mov	esi,ebx
	lea	ebx,[edi+10]
	mov	cl,[edi+8]
	call	add_register
	lea	ebx,[edi+11]
	mov	cl,[edi+9]
	call	add_register
	pop	esi
	jmp	calculation_loop
      add_register:
	or	cl,cl
	jz	add_register_done
      add_register_start:
	cmp	[esi+8],cl
	jne	add_in_second_slot
	mov	al,[ebx]
	add	[esi+10],al
	jnz	add_register_done
	mov	byte [esi+8],0
	ret
      add_in_second_slot:
	cmp	[esi+9],cl
	jne	create_in_first_slot
	mov	al,[ebx]
	add	[esi+11],al
	jnz	add_register_done
	mov	byte [esi+9],0
	ret
      create_in_first_slot:
	cmp	byte [esi+8],0
	jne	create_in_second_slot
	mov	[esi+8],cl
	mov	al,[ebx]
	mov	[esi+10],al
	ret
      create_in_second_slot:
	cmp	byte [esi+9],0
	jne	invalid_expression
	mov	[esi+9],cl
	mov	al,[ebx]
	mov	[esi+11],al
      add_register_done:
	ret
      calculate_sub:
	xor	ah,ah
	mov	ah,[ebx+12]
	mov	al,[edi+12]
	or	al,al
	jz	sub_values
	cmp	al,ah
	jne	invalid_sub
	xor	ah,ah
	mov	ecx,[edi+16]
	cmp	ecx,[ebx+16]
	jne	invalid_sub
      sub_values:
	mov	[ebx+12],ah
	mov	eax,[edi]
	sub	[ebx],eax
	mov	eax,[edi+4]
	sbb	[ebx+4],eax
	or	dx,dx
	jz	calculation_loop
	push	esi
	mov	esi,ebx
	lea	ebx,[edi+10]
	mov	cl,[edi+8]
	call	sub_register
	lea	ebx,[edi+11]
	mov	cl,[edi+9]
	call	sub_register
	pop	esi
	jmp	calculation_loop
      invalid_sub:
	cmp	[error_line],0
	jne	sub_values
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
	jmp	sub_values
      sub_register:
	or	cl,cl
	jz	add_register_done
	neg	byte [ebx]
	jmp	add_register_start
      calculate_mul:
	or	dx,dx
	jz	mul_start
	cmp	word [ebx+8],0
	jne	mul_start
	mov	eax,[ebx]
	xchg	eax,[edi]
	mov	[ebx],eax
	mov	eax,[ebx+4]
	xchg	eax,[edi+4]
	mov	[ebx+4],eax
	mov	eax,[ebx+8]
	xchg	eax,[edi+8]
	mov	[ebx+8],eax
	mov	eax,[ebx+12]
	xchg	eax,[edi+12]
	mov	[ebx+12],eax
      mul_start:
	push	esi edx
	mov	esi,ebx
	xor	bl,bl
	bt	dword [esi+4],31
	jnc	mul_first_sign_ok
	not	dword [esi]
	not	dword [esi+4]
	add	dword [esi],1
	adc	dword [esi+4],0
	not	bl
      mul_first_sign_ok:
	bt	dword [edi+4],31
	jnc	mul_second_sign_ok
	not	dword [edi]
	not	dword [edi+4]
	add	dword [edi],1
	adc	dword [edi+4],0
	not	bl
      mul_second_sign_ok:
	cmp	dword [esi+4],0
	jz	mul_numbers
	cmp	dword [edi+4],0
	jnz	value_out_of_range
      mul_numbers:
	mov	eax,[esi+4]
	mul	dword [edi]
	or	edx,edx
	jnz	value_out_of_range
	mov	ecx,eax
	mov	eax,[esi]
	mul	dword [edi+4]
	or	edx,edx
	jnz	value_out_of_range
	add	ecx,eax
	jc	value_out_of_range
	mov	eax,[esi]
	mul	dword [edi]
	add	edx,ecx
	jc	value_out_of_range
	test	edx,1 shl 31
	jnz	value_out_of_range
	mov	[esi],eax
	mov	[esi+4],edx
	or	bl,bl
	jz	mul_ok
	not	dword [esi]
	not	dword [esi+4]
	add	dword [esi],1
	adc	dword [esi+4],0
      mul_ok:
	pop	edx
	or	dx,dx
	jz	mul_calculated
	cmp	word [edi+8],0
	jne	invalid_value
	cmp	byte [esi+8],0
	je	mul_first_register_ok
	mov	al,[edi]
	cbw
	cwde
	cdq
	cmp	edx,[edi+4]
	jne	value_out_of_range
	cmp	eax,[edi]
	jne	value_out_of_range
	imul	byte [esi+10]
	mov	dl,ah
	cbw
	cmp	ah,dl
	jne	value_out_of_range
	mov	[esi+10],al
      mul_first_register_ok:
	cmp	byte [esi+9],0
	je	mul_calculated
	mov	al,[edi]
	cbw
	cwde
	cdq
	cmp	edx,[edi+4]
	jne	value_out_of_range
	cmp	eax,[edi]
	jne	value_out_of_range
	imul	byte [esi+11]
	mov	dl,ah
	cbw
	cmp	ah,dl
	jne	value_out_of_range
	mov	[esi+11],al
      mul_calculated:
	pop	esi
	jmp	calculation_loop
      calculate_div:
	push	esi edx
	mov	esi,ebx
	call	div_64
	pop	edx
	or	dx,dx
	jz	div_calculated
	cmp	byte [esi+8],0
	je	div_first_register_ok
	mov	al,[edi]
	cbw
	cwde
	cdq
	cmp	edx,[edi+4]
	jne	value_out_of_range
	cmp	eax,[edi]
	jne	value_out_of_range
	or	al,al
	jz	value_out_of_range
	mov	al,[esi+10]
	cbw
	idiv	byte [edi]
	or	ah,ah
	jnz	invalid_use_of_symbol
	mov	[esi+10],al
      div_first_register_ok:
	cmp	byte [esi+9],0
	je	div_calculated
	mov	al,[edi]
	cbw
	cwde
	cdq
	cmp	edx,[edi+4]
	jne	value_out_of_range
	cmp	eax,[edi]
	jne	value_out_of_range
	or	al,al
	jz	value_out_of_range
	mov	al,[esi+11]
	cbw
	idiv	byte [edi]
	or	ah,ah
	jnz	invalid_use_of_symbol
	mov	[esi+11],al
      div_calculated:
	pop	esi
	jmp	calculation_loop
      calculate_mod:
	push	esi
	mov	esi,ebx
	call	div_64
	mov	[esi],eax
	mov	[esi+4],edx
	pop	esi
	jmp	calculation_loop
      calculate_and:
	mov	eax,[edi]
	and	[ebx],eax
	mov	eax,[edi+4]
	and	[ebx+4],eax
	jmp	calculation_loop
      calculate_or:
	mov	eax,[edi]
	or	[ebx],eax
	mov	eax,[edi+4]
	or	[ebx+4],eax
	jmp	calculation_loop
      calculate_xor:
	mov	eax,[edi]
	xor	[ebx],eax
	mov	eax,[edi+4]
	xor	[ebx+4],eax
	jmp	calculation_loop
      shr_negative:
	not	dword [edi]
	not	dword [edi+4]
	add	dword [edi],1