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

	adc	dword [edi+4],0
      calculate_shl:
	mov	eax,dword [edi+4]
	bt	eax,31
	jc	shl_negative
	or	eax,eax
	jnz	zero_value
	mov	ecx,[edi]
	cmp	ecx,64
	jae	zero_value
	cmp	ecx,32
	jae	shl_high
	mov	edx,[ebx+4]
	mov	eax,[ebx]
	shld	edx,eax,cl
	shl	eax,cl
	mov	[ebx],eax
	mov	[ebx+4],edx
	jmp	calculation_loop
      shl_high:
	sub	cl,32
	mov	eax,[ebx]
	shl	eax,cl
	mov	[ebx+4],eax
	mov	dword [ebx],0
	jmp	calculation_loop
      shl_negative:
	not	dword [edi]
	not	dword [edi+4]
	add	dword [edi],1
	adc	dword [edi+4],0
      calculate_shr:
	mov	eax,dword [edi+4]
	bt	eax,31
	jc	shr_negative
	or	eax,eax
	jnz	zero_value
	mov	ecx,[edi]
	cmp	ecx,64
	jae	zero_value
	cmp	ecx,32
	jae	shr_high
	mov	edx,[ebx+4]
	mov	eax,[ebx]
	shrd	eax,edx,cl
	shr	edx,cl
	mov	[ebx],eax
	mov	[ebx+4],edx
	jmp	calculation_loop
      shr_high:
	sub	cl,32
	mov	eax,[ebx+4]
	shr	eax,cl
	mov	[ebx],eax
	mov	dword [ebx+4],0
	jmp	calculation_loop
      zero_value:
	mov	dword [ebx],0
	mov	dword [ebx+4],0
	jmp	calculation_loop
      calculate_not:
	cmp	word [edi+8],0
	jne	invalid_expression
	cmp	byte [edi+12],0
	je	not_ok
	cmp	[error_line],0
	jne	not_ok
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      not_ok:
	cmp	[value_size],1
	je	not_byte
	cmp	[value_size],2
	je	not_word
	cmp	[value_size],4
	je	not_dword
	cmp	[value_size],6
	je	not_pword
      not_qword:
	not	dword [edi]
	not	dword [edi+4]
	add	edi,14h
	jmp	calculation_loop
      not_byte:
	cmp	dword [edi+4],0
	jne	not_qword
	cmp	word [edi+2],0
	jne	not_qword
	cmp	byte [edi+1],0
	jne	not_qword
	not	byte [edi]
	add	edi,14h
	jmp	calculation_loop
      not_word:
	cmp	dword [edi+4],0
	jne	not_qword
	cmp	word [edi+2],0
	jne	not_qword
	not	word [edi]
	add	edi,14h
	jmp	calculation_loop
      not_dword:
	cmp	dword [edi+4],0
	jne	not_qword
	not	dword [edi]
	add	edi,14h
	jmp	calculation_loop
      not_pword:
	cmp	word [edi+6],0
	jne	not_qword
	not	dword [edi]
	not	word [edi+4]
	add	edi,14h
	jmp	calculation_loop
      calculate_neg:
	cmp	word [edi+8],0
	jne	invalid_expression
	cmp	byte [edi+12],0
	je	neg_ok
	cmp	[error_line],0
	jne	neg_ok
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      neg_ok:
	mov	eax,[edi]
	mov	edx,[edi+4]
	mov	dword [edi],0
	mov	dword [edi+4],0
	sub	[edi],eax
	sbb	[edi+4],edx
	add	edi,14h
	jmp	calculation_loop
      calculate_rva:
	cmp	word [edi+8],0
	jne	invalid_expression
	cmp	[output_format],5
	je	calculate_gotoff
	cmp	[output_format],3
	jne	invalid_expression
	test	[format_flags],8
	jnz	pe64_rva
	mov	al,2
	bt	[resolver_flags],0
	jc	rva_type_ok
	xor	al,al
      rva_type_ok:
	cmp	byte [edi+12],al
	je	rva_ok
	cmp	[error_line],0
	jne	rva_ok
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      rva_ok:
	mov	byte [edi+12],0
	mov	eax,[code_start]
	mov	eax,[eax+34h]
	cdq
	sub	[edi],eax
	sbb	[edi+4],edx
	add	edi,14h
	jmp	calculation_loop
      pe64_rva:
	mov	al,4
	bt	[resolver_flags],0
	jc	pe64_rva_type_ok
	xor	al,al
      pe64_rva_type_ok:
	cmp	byte [edi+12],al
	je	pe64_rva_ok
	cmp	[error_line],0
	jne	pe64_rva_ok
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      pe64_rva_ok:
	mov	byte [edi+12],0
	mov	eax,[code_start]
	mov	edx,[eax+34h]
	mov	eax,[eax+30h]
	sub	[edi],eax
	sbb	[edi+4],edx
	add	edi,14h
	jmp	calculation_loop
      calculate_gotoff:
	test	[format_flags],8+1
	jnz	invalid_expression
	mov	dl,5
	cmp	byte [edi+12],2
	je	change_value_type
      incorrect_change_of_value_type:
	cmp	[error_line],0
	jne	change_value_type
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      change_value_type:
	mov	byte [edi+12],dl
	add	edi,14h
	jmp	calculation_loop
      calculate_plt:
	cmp	word [edi+8],0
	jne	invalid_expression
	cmp	[output_format],5
	jne	invalid_expression
	test	[format_flags],1
	jnz	invalid_expression
	mov	dl,6
	mov	dh,2
	test	[format_flags],8
	jz	check_value_for_plt
	mov	dh,4
      check_value_for_plt:
	mov	eax,[edi]
	or	eax,[edi+4]
	jnz	incorrect_change_of_value_type
	cmp	byte [edi+12],dh
	jne	incorrect_change_of_value_type
	mov	eax,[edi+16]
	cmp	byte [eax],81h
	jne	incorrect_change_of_value_type
	jmp	change_value_type
      div_64:
	xor	ebx,ebx
	cmp	dword [edi],0
	jne	divider_ok
	cmp	dword [edi+4],0
	jne	divider_ok
	cmp	[next_pass_needed],0
	je	value_out_of_range
	jmp	div_done
      divider_ok:
	bt	dword [esi+4],31
	jnc	div_first_sign_ok
	not	dword [esi]
	not	dword [esi+4]
	add	dword [esi],1
	adc	dword [esi+4],0
	not	bx
      div_first_sign_ok:
	bt	dword [edi+4],31
	jnc	div_second_sign_ok
	not	dword [edi]
	not	dword [edi+4]
	add	dword [edi],1
	adc	dword [edi+4],0
	not	bl
      div_second_sign_ok:
	cmp	dword [edi+4],0
	jne	div_high
	mov	ecx,[edi]
	mov	eax,[esi+4]
	xor	edx,edx
	div	ecx
	mov	[esi+4],eax
	mov	eax,[esi]
	div	ecx
	mov	[esi],eax
	mov	eax,edx
	xor	edx,edx
	jmp	div_done
      div_high:
	mov	eax,[esi+4]
	xor	edx,edx
	div	dword [edi+4]
	mov	ebx,[esi]
	mov	[esi],eax
	mov	dword [esi+4],0
	mov	ecx,edx
	mul	dword [edi]
      div_high_loop:
	cmp	ecx,edx
	ja	div_high_done
	jb	div_high_large_correction
	cmp	ebx,eax
	jae	div_high_done
      div_high_correction:
	dec	dword [esi]
	sub	eax,[edi]
	sbb	edx,[edi+4]
	jnc	div_high_loop
      div_high_done:
	sub	ebx,eax
	sbb	ecx,edx
	mov	edx,ecx
	mov	eax,ebx
	ret
      div_high_large_correction:
	push	eax edx
	mov	eax,edx
	sub	eax,ecx
	xor	edx,edx
	div	dword [edi+4]
	shr	eax,1
	jz	div_high_small_correction
	sub	[esi],eax
	push	eax
	mul	dword [edi+4]
	sub	dword [esp+4],eax
	pop	eax
	mul	dword [edi]
	sub	dword [esp+4],eax
	sbb	dword [esp],edx
	pop	edx eax
	jmp	div_high_loop
      div_high_small_correction:
	pop	edx eax
	jmp	div_high_correction
      div_done:
	or	bh,bh
	jz	remainder_ok
	not	eax
	not	edx
	add	eax,1
	adc	edx,0
      remainder_ok:
	or	bl,bl
	jz	div_ok
	not	dword [esi]
	not	dword [esi+4]
	add	dword [esi],1
	adc	dword [esi+4],0
      div_ok:
	ret
      convert_fp:
	inc	esi
	mov	word [edi+8],0
	mov	byte [edi+12],0
	mov	al,[value_size]
	cmp	al,4
	je	convert_fp_dword
	cmp	al,8
	je	convert_fp_qword
	jmp	invalid_value
      convert_fp_dword:
	xor	eax,eax
	cmp	word [esi+8],8000h
	je	fp_dword_store
	mov	bx,[esi+8]
	mov	eax,[esi+4]
	shl	eax,1
	shr	eax,9
	jnc	fp_dword_ok
	inc	eax
	bt	eax,23
	jnc	fp_dword_ok
	and	eax,1 shl 23 - 1
	inc	bx
	shr	eax,1
      fp_dword_ok:
	add	bx,7Fh
	cmp	bx,100h
	jae	value_out_of_range
	shl	ebx,23
	or	eax,ebx
      fp_dword_store:
	mov	bl,[esi+11]
	shl	ebx,31
	or	eax,ebx
	mov	[edi],eax
	xor	eax,eax
	mov	[edi+4],eax
	add	esi,13
	ret
      convert_fp_qword:
	xor	eax,eax
	xor	edx,edx
	cmp	word [esi+8],8000h
	je	fp_qword_store
	mov	bx,[esi+8]
	mov	eax,[esi]
	mov	edx,[esi+4]
	add	eax,eax
	adc	edx,edx
	mov	ecx,edx
	shr	edx,12
	shrd	eax,ecx,12
	jnc	fp_qword_ok
	add	eax,1
	adc	edx,0
	bt	edx,20
	jnc	fp_qword_ok
	and	edx,1 shl 20 - 1
	inc	bx
	shr	edx,1
	rcr	eax,1
      fp_qword_ok:
	add	bx,3FFh
	cmp	bx,800h
	jae	value_out_of_range
	shl	ebx,20
	or	edx,ebx
      fp_qword_store:
	mov	bl,[esi+11]
	shl	ebx,31
	or	edx,ebx
	mov	[edi],eax
	mov	[edi+4],edx
	add	esi,13
	ret
      get_string_value:
	inc	esi
	lods	dword [esi]
	mov	ecx,eax
	cmp	ecx,8
	ja	value_out_of_range
	mov	edx,edi
	xor	eax,eax
	stos	dword [edi]
	stos	dword [edi]
	mov	edi,edx
	rep	movs byte [edi],[esi]
	mov	edi,edx
	inc	esi
	mov	word [edi+8],0
	mov	byte [edi+12],0
	ret

get_byte_value:
	mov	[value_size],1
	mov	[size_override],-1
	call	calculate_expression
	mov	eax,[edi+16]
	mov	[symbol_identifier],eax
	mov	[value_type],0
	cmp	word [edi+8],0
	jne	invalid_value
	cmp	byte [edi+12],0
	je	check_byte_value
	cmp	[error_line],0
	jne	check_byte_value
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      check_byte_value:
	mov	eax,[edi]
	mov	edx,[edi+4]
	or	edx,edx
	jz	byte_positive
	cmp	edx,-1
	jne	range_exceeded
	cmp	eax,-80h
	jb	range_exceeded
	ret
      byte_positive:
	cmp	eax,100h
	jae	range_exceeded
      return_byte_value:
	ret
      range_exceeded:
	xor	eax,eax
	xor	edx,edx
	cmp	[error_line],0
	jne	return_byte_value
	mov	ecx,[current_line]
	mov	[error_line],ecx
	mov	[error],value_out_of_range
	ret
get_word_value:
	mov	[value_size],2
	mov	[size_override],-1
	call	calculate_expression
	mov	eax,[edi+16]
	mov	[symbol_identifier],eax
	cmp	word [edi+8],0
	jne	invalid_value
	mov	al,[edi+12]
	mov	[value_type],al
	cmp	al,2
	jb	check_word_value
	cmp	[error_line],0
	jne	check_word_value
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      check_word_value:
	mov	eax,[edi]
	mov	edx,[edi+4]
	or	edx,edx
	jz	word_positive
	cmp	edx,-1
	jne	range_exceeded
	cmp	eax,-8000h
	jb	range_exceeded
	ret
      word_positive:
	cmp	eax,10000h
	jae	range_exceeded
	ret
get_dword_value:
	mov	[value_size],4
	mov	[size_override],-1
	call	calculate_expression
	mov	eax,[edi+16]
	mov	[symbol_identifier],eax
	cmp	word [edi+8],0
	jne	invalid_value
	mov	al,[edi+12]
	mov	[value_type],al
	cmp	al,4
	jne	check_dword_value
	mov	[value_type],2
	mov	eax,[edi]
	cdq
	cmp	edx,[edi+4]
	jne	range_exceeded
	ret
      check_dword_value:
	mov	eax,[edi]
	mov	edx,[edi+4]
	or	edx,edx
	jz	dword_positive
	cmp	edx,-1
	jne	range_exceeded
	bt	eax,31
	jnc	range_exceeded
      dword_positive:
	ret
get_pword_value:
	mov	[value_size],6
	mov	[size_override],-1
	call	calculate_expression
	mov	eax,[edi+16]
	mov	[symbol_identifier],eax
	cmp	word [edi+8],0
	jne	invalid_value
	mov	al,[edi+12]
	mov	[value_type],al
	cmp	al,4
	jne	check_pword_value
	cmp	[error_line],0
	jne	check_pword_value
	mov	eax,[current_line]
	mov	[error_line],eax
	mov	[error],invalid_use_of_symbol
      check_pword_value:
	mov	eax,[edi]
	mov	edx,[edi+4]
	cmp	edx,10000h
	jge	range_exceeded
	cmp	edx,-8000h
	jl	range_exceeded
	ret
get_qword_value:
	mov	[value_size],8
	mov	[size_override],-1
	call	calculate_expression
	mov	eax,[edi+16]
	mov	[symbol_identifier],eax
	cmp	word [edi+8],0
	jne	invalid_value
	mov	al,[edi+12]
	mov	[value_type],al
      check_qword_value:
	mov	eax,[edi]
	mov	edx,[edi+4]
	ret
get_value:
	mov	[operand_size],0
	lods	byte [esi]
	call	get_size_operator
	cmp	al,'('
	jne	invalid_value
	mov	al,[operand_size]
	cmp	al,1
	je	value_byte
	cmp	al,2
	je	value_word
	cmp	al,4
	je	value_dword
	cmp	al,6
	je	value_pword
	cmp	al,8
	je	value_qword
	or	al,al
	jnz	invalid_value
      value_qword:
	call	get_qword_value
	ret
      value_pword:
	call	get_pword_value
	movzx	edx,dx
	ret
      value_dword:
	call	get_dword_value
	xor	edx,edx
	ret
      value_word:
	call	get_word_value
	xor	edx,edx
	movzx	eax,ax
	ret
      value_byte:
	call	get_byte_value
	xor	edx,edx
	movzx	eax,al
	ret
get_address_value:
	mov	[address_size],0
	mov	[value_size],8
      calculate_address:
	cmp	byte [esi],'.'
	je	invalid_address
	call	calculate_expression
	mov	eax,[edi+16]
	mov	[address_symbol],eax
	mov	al,[edi+12]
	mov	[value_type],al
	cmp	al,5
	je	gotoff_address
	ja	invalid_use_of_symbol
	test	al,1
	jnz	invalid_use_of_symbol
	or	al,al
	jz	address_size_ok
	shl	al,5
	jmp	address_symbol_ok
      gotoff_address:
	mov	al,40h
      address_symbol_ok:
	mov	ah,[address_size]
	or	[address_size],al
	shr	al,4
	or	ah,ah
	jz	address_size_ok
	cmp	al,ah
	je	address_size_ok
	cmp	ax,0408h
	jne	address_sizes_do_not_agree
	mov	[value_type],2
	mov	eax,[edi]
	cdq
	cmp	edx,[edi+4]
	je	address_size_ok
	cmp	[error_line],0
	jne	address_size_ok
	mov	ecx,[current_line]
	mov	[error_line],ecx
	mov	[error],value_out_of_range
      address_size_ok:
	xor	ebx,ebx
	xor	ecx,ecx
	mov	cl,[value_type]
	shl	ecx,16
	mov	ch,[address_size]
	cmp	word [edi+8],0
	je	check_immediate_address
	mov	al,[edi+8]
	mov	dl,[edi+10]
	call	get_address_register
	mov	al,[edi+9]
	mov	dl,[edi+11]
	call	get_address_register
	mov	ax,bx
	shr	ah,4
	shr	al,4
	or	bh,bh
	jz	check_address_registers
	or	bl,bl
	jz	check_address_registers
	cmp	al,ah
	jne	invalid_address
      check_address_registers:
	or	al,ah
	mov	ah,[address_size]
	and	ah,0Fh
	jz	address_registers_sizes_ok
	cmp	al,ah
	jne	address_sizes_do_not_match
      address_registers_sizes_ok:
	cmp	al,4
	je	sib_allowed
	cmp	al,8
	je	sib_allowed
	cmp	al,0Fh
	je	check_ip_relative_address
	or	cl,cl
	jz	check_word_value
	cmp	cl,1
	je	check_word_value
	jmp	invalid_address