## Copyright (C) 2016 Jeremiah Orians ## This file is part of stage0. ## ## stage0 is free software: you an redistribute it and/or modify ## it under the terms of the GNU General Public License as published by ## the Free Software Foundation, either version 3 of the License, or ## (at your option) any later version. ## ## stage0 is distributed in the hope that it will be useful, ## but WITHOUT ANY WARRANTY; without even the implied warranty of ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the ## GNU General Public License for more details. ## ## You should have received a copy of the GNU General Public License ## along with stage0. If not, see . :start 2D2D @table # LOADUI R13 @table ; Where we are putting our table # ;; We will be using R14 for our condition codes 2D2F7fff # LOADUI R15 0x7FFF ; We will be using R15 for our stack # ;; Main program functionality # ;; Reads in Tape_01 and writes out results onto Tape_02 # ;; Accepts no arguments and HALTS when done :main # ;; Prep TAPE_01 2D201100 # LOADUI R0 0x1100 42100000 # FOPEN_READ # ;; Intialize environment 0D00002C # FALSE R12 ; Set holder to zero 0D00002B # FALSE R11 ; Set PC counter to zero 2D2A0001 # LOADUI R10 1 ; Our toggle # ;; Perform first pass 2D0F @first_pass # CALLI R15 @first_pass # ;; We need to rewind tape_01 to perform our second pass 2D201100 # LOADUI R0 0x1100 42100003 # REWIND # ;; Reintialize environment 0D00002C # FALSE R12 ; Set holder to zero 0D00002B # FALSE R11 ; Set PC counter to zero 2D2A0001 # LOADUI R10 1 ; Our toggle 2D2900ff # LOADUI R9 0xFF ; Byte mask 2D28000f # LOADUI R8 0x0F ; nybble mask # ;; Prep TAPE_02 2D201101 # LOADUI R0 0x1101 42100001 # FOPEN_WRITE 2D0F @second_pass # CALLI R15 @second_pass # ;; Close up as we are done 2D201100 # LOADUI R0 0x1100 ; Close TAPE_01 42100002 # FCLOSE 2D201101 # LOADUI R0 0x1101 ; Close TAPE_02 42100002 # FCLOSE FFFFFFFF # HALT # ;; First pass function # ;; Reads Tape_01 and creates our label table # ;; Will Overwrite R0 R10 R11 # ;; Returns to Main function when done :first_pass 2D211100 # LOADUI R1 0x1100 ; Read from tape_01 42100100 # FGETC ; Read a Char # ;; Check for EOF A0100000 # CMPSKIPI.GE R0 0 0D01001F # RET R15 # ;; Check for and deal with label (:) A030003a # CMPSKIPI.NE R0 58 3C00 @storeLabel # JUMP @storeLabel # ;; Check for and deal with pointers to labels # ;; Starting with (@) A0300040 # CMPSKIPI.NE R0 64 3C00 @ThrowAwayPointer # JUMP @ThrowAwayPointer # ;; Then dealing with ($) A0300024 # CMPSKIPI.NE R0 36 3C00 @ThrowAwayPointer # JUMP @ThrowAwayPointer # ;; Now check for absolute addresses (&) A0300026 # CMPSKIPI.NE R0 38 3C00 @ThrowAwayAddress # JUMP @ThrowAwayAddress # ;; Otherwise attempt to process 2D0F @hex # CALLI R15 @hex ; Convert it A0100000 # CMPSKIPI.GE R0 0 ; Don't record, nonhex values 3C00 @first_pass # JUMP @first_pass ; Move onto Next char # ;; Determine if we got a full byte 2C9A @first_pass_0 # JUMP.Z R10 @first_pass_0 ; Jump if toggled # ;; Deal with case of first half of byte 0D00002A # FALSE R10 ; Flip the toggle 3C00 @first_pass # JUMP @first_pass :first_pass_0 # ;; Deal with case of second half of byte 0D00003A # TRUE R10 ; Flip the toggle 0FBB0001 # ADDUI R11 R11 1 ; increment PC now that that we have a full byte 3C00 @first_pass # JUMP @first_pass # ;; Second pass function # ;; Reads from Tape_01 and uses the values in the table # ;; To write desired contents onto Tape_02 # ;; Will Overwrite R0 R10 R11 # ;; Returns to Main function when done :second_pass 2D211100 # LOADUI R1 0x1100 ; Read from tape_01 42100100 # FGETC ; Read a Char # ;; Check for EOF A0100000 # CMPSKIPI.GE R0 0 0D01001F # RET R15 # ;; Check for and deal with label A030003a # CMPSKIPI.NE R0 58 3C00 @ThrowAwayLabel # JUMP @ThrowAwayLabel # ;; Check for and deal with Pointers to labels A0300040 # CMPSKIPI.NE R0 64 ; @ for relative 3C00 @StoreRelativePointer # JUMP @StoreRelativePointer A0300024 # CMPSKIPI.NE R0 36 ; $ for absolute 3C00 @StoreAbsolutePointer # JUMP @StoreAbsolutePointer A0300026 # CMPSKIPI.NE R0 38 ; & for address 3C00 @StoreAbsoluteAddress # JUMP @StoreAbsoluteAddress # ;; Process everything else 2D0F @hex # CALLI R15 @hex ; Attempt to Convert it A0100000 # CMPSKIPI.GE R0 0 ; Don't record, nonhex values 3C00 @second_pass # JUMP @second_pass ; Move onto Next char # ;; Determine if we got a full byte 2C9A @second_pass_0 # JUMP.Z R10 @second_pass_0 ; Jump if toggled # ;; Deal with case of first half of byte 05020C08 # AND R12 R0 R8 ; Store our first nibble 0D00002A # FALSE R10 ; Flip the toggle 3C00 @second_pass # JUMP @second_pass :second_pass_0 # ;; Deal with case of second half of byte 2D5C0004 # SL0I R12 4 ; Shift our first nybble 05020008 # AND R0 R0 R8 ; Mask out top 0500000C # ADD R0 R0 R12 ; Combine nybbles 0D00003A # TRUE R10 ; Flip the toggle 2D211101 # LOADUI R1 0x1101 ; Write the combined byte 42100200 # FPUTC ; To TAPE_02 0FBB0001 # ADDUI R11 R11 1 ; increment PC now that that we have a full byte 3C00 @second_pass # JUMP @second_pass # ;; Store Label function # ;; Writes out the token and the current PC value # ;; Its static variable for storing the next index to be used # ;; Will overwrite R0 # ;; Returns to first pass when done :storeLabel 2E00 @current_index # LOADR R0 @current_index ; Get address of first open index A0300000 # CMPSKIPI.NE R0 0 ; If zero intialize from R13 0900040D # COPY R0 R13 # ;; Store the PC of the label 23B00000 # STORE32 R11 R0 0 # ;; Store the name of the Label 0F000004 # ADDUI R0 R0 4 ; Increment the offset of the index 2D0F @writeout_token # CALLI R15 @writeout_token # ;; Update our index 0F00003c # ADDUI R0 R0 60 ; Hopefully our tokens are less than 60 bytes long 2F00 @current_index # STORER R0 @current_index # ;; And be done 3C00 @first_pass # JUMP @first_pass # ;; Where we are storing the location of the next free table entry :current_index 00000000 # NOP # ;; StoreRelativepointer function # ;; Deals with the special case of relative pointers # ;; Clears Temp # ;; Stores string in Temp # ;; Finds match in Table # ;; Writes out the offset # ;; Modifies R0 R11 # ;; Jumps back into Pass2 :StoreRelativePointer # ;; Correct the PC to reflect the size of the pointer 0FBB0002 # ADDUI R11 R11 2 ; Exactly 2 bytes 2D20 $Temp # LOADUI R0 $Temp ; Set where we want to shove our string 2D0F @Clear_string # CALLI R15 @Clear_string ; Clear it 2D0F @writeout_token # CALLI R15 @writeout_token ; Write it 2D0F @Match_string # CALLI R15 @Match_string ; Find the Match 1800fffc # LOAD32 R0 R0 -4 ; Get the value we care about 0500200B # SUB R0 R0 R11 ; Determine the difference 0F000004 # ADDUI R0 R0 4 ; Adjust for relative positioning 2D0F @ProcessImmediate # CALLI R15 @ProcessImmediate ; Write out the value 3C00 @second_pass # JUMP @second_pass # ;; StoreAbsolutepointer function # ;; Deals with the special case of absolute pointers # ;; Clears Temp # ;; Stores string in Temp # ;; Finds match in Table # ;; Writes out the absolute address of match # ;; Modifies R0 R11 # ;; Jumps back into Pass2 :StoreAbsolutePointer # ;; Correct the PC to reflect the size of the pointer 0FBB0002 # ADDUI R11 R11 2 ; Exactly 2 bytes 2D20 $Temp # LOADUI R0 $Temp ; Set where we want to shove our string 2D0F @Clear_string # CALLI R15 @Clear_string ; Clear it 2D0F @writeout_token # CALLI R15 @writeout_token ; Write it 2D0F @Match_string # CALLI R15 @Match_string ; Find the Match 1800fffc # LOAD32 R0 R0 -4 ; Get the value we care about 2D0F @ProcessImmediate # CALLI R15 @ProcessImmediate ; Write out the value 3C00 @second_pass # JUMP @second_pass # ;; StoreAbsoluteAddress function # ;; Deal with the special case of absolute Addresses # ;; Clear Temp # ;; Stores string in Temp # ;; Finds match in Table # ;; Writes out the full absolute address [32 bit machine] # ;; Modifies R0 R11 # ;; Jumpbacs back into Pass2 :StoreAbsoluteAddress # ;; COrrect the PC to reflect the size of the address 0FBB0004 # ADDUI R11 R11 4 ; 4 Bytes on 32bit machines 2D20 $Temp # LOADUI R0 $Temp ; Set where we ant to shove our string 2D0F @Clear_string # CALLI R15 @Clear_string ; Clear it 2D0F @writeout_token # CALLI R15 @writeout_token ; Write it 2D0F @Match_string # CALLI R15 @Match_string ; Find the Match 090200EF # PUSHR R14 R15 ; Get a temp storage place 18E0fffc # LOAD32 R14 R0 -4 ; Get the value we care about 0900040E # COPY R0 R14 ; We need to print the top 2 bytes first 2D400010 # SARI R0 16 ; Drop bottom 16 bits 2D0F @ProcessImmediate # CALLI R15 @ProcessImmediate ; Write out top 2 bytes 2D20ffff # LOADUI R0 0xFFFF ; Provide mask to keep bottom 2 bytes 0502000E # AND R0 R0 R14 ; Drop top 16 bits 090280EF # POPR R14 R15 ; Restore R14 2D0F @ProcessImmediate # CALLI R15 @ProcessImmediate ; Write out bottom 2 bytes 3C00 @second_pass # JUMP @second_pass # ;; Writeout Token Function # ;; Writes the Token [minus first char] to the address # ;; It recieves in R0 until it reaches a delimiter # ;; All register values are preserved # ;; Returns to whatever called it :writeout_token # ;; Preserve registers 0902000F # PUSHR R0 R15 0902001F # PUSHR R1 R15 0902002F # PUSHR R2 R15 # ;; Initialize 09000520 # MOVE R2 R0 ; Set R2 as our index 2D211100 # LOADUI R1 0x1100 ; Read from tape_01 # ;; Our core loop :writeout_token_0 42100100 # FGETC ; Get another byte # ;; Deal with termination cases A0300020 # CMPSKIPI.NE R0 32 ; Finished if space 3C00 @writeout_token_done # JUMP @writeout_token_done A0300009 # CMPSKIPI.NE R0 9 ; Finished if tab 3C00 @writeout_token_done # JUMP @writeout_token_done A030000a # CMPSKIPI.NE R0 10 ; Finished if newline 3C00 @writeout_token_done # JUMP @writeout_token_done # ;; Deal with valid input 21020000 # STORE8 R0 R2 0 ; Write out the byte 0F220001 # ADDUI R2 R2 1 ; Increment 3C00 @writeout_token_0 # JUMP @writeout_token_0 ; Keep looping # ;; Clean up now that we are done :writeout_token_done # ;; Restore registers 0902802F # POPR R2 R15 0902801F # POPR R1 R15 0902800F # POPR R0 R15 # ;; And be done 0D01001F # RET R15 # ;; Clear string function # ;; Clears string pointed at by the value of R0 # ;; Until a null character is reached # ;; Doesn't alter any registers # ;; Returns to the function that calls it :Clear_string # ;; Preserve registers 0902000F # PUSHR R0 R15 0902001F # PUSHR R1 R15 0902002F # PUSHR R2 R15 0902003F # PUSHR R3 R15 # ;; Setup registers 09000510 # MOVE R1 R0 2D220000 # LOADUI R2 0 2D230000 # LOADUI R3 0 :clear_byte 0503A012 # LOADXU8 R0 R1 R2 ; Get the byte 05049312 # STOREX8 R3 R1 R2 ; Overwrite with a Zero 0F220001 # ADDUI R2 R2 1 ; Prep for next loop 2CA0 @clear_byte # JUMP.NZ R0 @clear_byte ; Stop if byte is NULL # ;; Done # ;; Restore registers 0902803F # POPR R3 R15 0902802F # POPR R2 R15 0902801F # POPR R1 R15 0902800F # POPR R0 R15 0D01001F # RET R15 # ;; Match string function # ;; Walks down table until match is found # ;; Then returns address of matching string in R0 # ;; Returns to whatever called it :Match_string # ;; Preserve registers 0902001F # PUSHR R1 R15 0902002F # PUSHR R2 R15 # ;; Initialize for Loop 2D21 $Temp # LOADUI R1 $Temp ; We always compare against Temp 2D22 $table # LOADUI R2 $table ; Begin at start of table 0F220004 # ADDUI R2 R2 4 ; Where the string is located # ;; Loop until we find a match :Match_string_0 09000402 # COPY R0 R2 ; Set R0 to our current string 2D0F @strcmp # CALLI R15 @strcmp 2C50 @Match_string_1 # JUMP.E R0 @Match_string_1 ; It is a match! # ;; Prepare for next loop 2D21 $Temp # LOADUI R1 $Temp ; That function clears R1 0F220040 # ADDUI R2 R2 64 ; Each Index is 64 bytes 3C00 @Match_string_0 # JUMP @Match_string_0 ; Keep looping :Match_string_1 # ;; Store the correct answer 09000502 # MOVE R0 R2 # ;; Restore registers 0902802F # POPR R2 R15 0902801F # POPR R1 R15 0D01001F # RET R15 # ;; Our simple string compare function # ;; Recieves two pointers in R0 and R1 # ;; Returns the difference between the strings in R0 # ;; Clears R1 # ;; Returns to whatever called it :strcmp # ;; Preserve registers 0902002F # PUSHR R2 R15 0902003F # PUSHR R3 R15 0902004F # PUSHR R4 R15 # ;; Setup registers 09000520 # MOVE R2 R0 09000531 # MOVE R3 R1 2D240000 # LOADUI R4 0 :cmpbyte 0503A024 # LOADXU8 R0 R2 R4 ; Get a byte of our first string 0503A134 # LOADXU8 R1 R3 R4 ; Get a byte of our second string 0F440001 # ADDUI R4 R4 1 ; Prep for next loop 05004101 # CMP R1 R0 R1 ; Compare the bytes A0200000 # CMPSKIPI.E R0 0 ; Stop if byte is NULL 2C51 @cmpbyte # JUMP.E R1 @cmpbyte ; Loop if bytes are equal # ;; Done 09000501 # MOVE R0 R1 ; Prepare for return # ;; Restore registers 0902804F # POPR R4 R15 0902803F # POPR R3 R15 0902802F # POPR R2 R15 0D01001F # RET R15 # ;; Processimmediate Function # ;; Recieves an integer value in R0 # ;; Writes out the values to Tape_02 # ;; Doesn't modify registers # ;; Returns to whatever called it :ProcessImmediate # ;; Preserve registers 0902000F # PUSHR R0 R15 0902001F # PUSHR R1 R15 0902002F # PUSHR R2 R15 # ;; Break up Immediate 05020209 # AND R2 R0 R9 ; Put lower byte in R2 2D400008 # SARI R0 8 ; Drop Bottom byte from R0 05020009 # AND R0 R0 R9 ; Maskout everything outside of top byte # ;; Write out Top Byte 2D211101 # LOADUI R1 0x1101 ; Write the byte 42100200 # FPUTC ; To TAPE_02 # ;; Write out bottom Byte 09000502 # MOVE R0 R2 ; Put Lower byte in R0 2D211101 # LOADUI R1 0x1101 ; Write the byte 42100200 # FPUTC ; To TAPE_02 # ;; Restore registers 0902802F # POPR R2 R15 0902801F # POPR R1 R15 0902800F # POPR R0 R15 # ;; Be Done 0D01001F # RET R15 # ;; ThrowAwaypointer function # ;; Handle the special case of a generic problem # ;; for Pass1, Will update R11 and modify R0 # ;; Will return to the start of first_pass # ;; Never call this function, only jump to it :ThrowAwayPointer 0FBB0002 # ADDUI R11 R11 2 ; Pointers always take up 2 bytes 2D0F @throwAwayToken # CALLI R15 @throwAwayToken ; Get rid of rest of token 3C00 @first_pass # JUMP @first_pass ; Then return to the proper place # ;; ThrowAwayAddress function # ;; Handle the case of a 32bit absolute address storage # ;; for Pass1, Will update R11 and modify R0 # ;; Will return to the start of first_pass # ;; Never call this function, conly jump to it :ThrowAwayAddress 0FBB0004 # ADDUI R11 R11 4 ; Addresses on 32bit systems take up 4 bytes 2D0F @throwAwayToken # CALLI R15 @throwAwayToken ; Get rid of rest of token 3C00 @first_pass # JUMP @first_pass ; Then return to the proper place # ;; ThrowAwaylabel function # ;; Handle the special case of a generic problem # ;; for Pass2, Will update R11 and modify R0 # ;; Will return to the start of second_pass # ;; Never call this function, only jump to it :ThrowAwayLabel 2D0F @throwAwayToken # CALLI R15 @throwAwayToken ; Get rid of rest of token 3C00 @second_pass # JUMP @second_pass # ;; Throw away token function # ;; Deals with the general case of not wanting # ;; The rest of the characters in a token # ;; This Will alter the values of R0 R1 # ;; Returns back to whatever called it :throwAwayToken 2D211100 # LOADUI R1 0x1100 ; Read from tape_01 42100100 # FGETC ; Read a Char # ;; Stop looping if space A0300020 # CMPSKIPI.NE R0 32 0D01001F # RET R15 # ;; Stop looping if tab A0300009 # CMPSKIPI.NE R0 9 0D01001F # RET R15 # ;; Stop looping if newline A030000a # CMPSKIPI.NE R0 10 0D01001F # RET R15 # ;; Otherwise keep looping 3C00 @throwAwayToken # JUMP @throwAwayToken # ;; Hex function # ;; This function is serving three purposes: # ;; Identifying hex characters # ;; Purging line comments # ;; Returning the converted value of a hex character # ;; This function will alter the values of R0 R14 # ;; Returns back to whatever called it :hex # ;; Deal with line comments starting with # 1FE00023 # CMPUI R14 R0 35 2C5E @ascii_comment # JUMP.E R14 @ascii_comment # ;; Deal with line comments starting with ; 1FE0003b # CMPUI R14 R0 59 2C5E @ascii_comment # JUMP.E R14 @ascii_comment # ;; Deal with all ascii less than '0' 1FE00030 # CMPUI R14 R0 48 2C8E @ascii_other # JUMP.L R14 @ascii_other # ;; Deal with '0'-'9' 1FE00039 # CMPUI R14 R0 57 2C7E @ascii_num # JUMP.LE R14 @ascii_num # ;; Deal with all ascii less than 'A' 1FE00041 # CMPUI R14 R0 65 2C8E @ascii_other # JUMP.L R14 @ascii_other # ;; Deal with 'A'-'F' 1FE00046 # CMPUI R14 R0 70 2C7E @ascii_high # JUMP.LE R14 @ascii_high # ;; Deal with all ascii less than 'a' 1FE00061 # CMPUI R14 R0 97 2C8E @ascii_other # JUMP.L R14 @ascii_other # ;; Deal with 'a'-'f' 1FE00066 # CMPUI R14 R0 102 2C7E @ascii_low # JUMP.LE R14 @ascii_low # ;; Ignore the rest 3C00 @ascii_other # JUMP @ascii_other :ascii_num 11000030 # SUBUI R0 R0 48 0D01001F # RET R15 :ascii_low 11000057 # SUBUI R0 R0 87 0D01001F # RET R15 :ascii_high 11000037 # SUBUI R0 R0 55 0D01001F # RET R15 :ascii_other 0D000030 # TRUE R0 0D01001F # RET R15 :ascii_comment 2D211100 # LOADUI R1 0x1100 ; Read from TAPE_01 42100100 # FGETC ; Read another char 1FE0000a # CMPUI R14 R0 10 ; Stop at the end of line 2C6E @ascii_comment # JUMP.NE R14 @ascii_comment ; Otherwise keep looping 3C00 @ascii_other # JUMP @ascii_other # ;; Where we are storing our Temp :Temp 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP 00000000 # NOP # ;; Where we will putting our Table :table