├── LICENSE ├── README.md ├── _config.yml ├── _riscv_double_linked_lists.s ├── assets ├── riscv.gif ├── tests.mp4 └── thumbnail.png └── documentation.pdf /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. By contrast, 15 | the GNU General Public License is intended to guarantee your freedom to 16 | share and change all versions of a program--to make sure it remains free 17 | software for all its users. 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It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # RISC-V Project: Double Linked-list Simulation 2 | 3 | ## Overview 4 | This project implements a RISC-V assembly program that processes a series of list manipulation commands provided as a single input string. The input string, declared as `listInput` in the `.data` section, contains commands separated by the `~` character (ASCII 126). The main function and associated functions handle commands to add, delete, print, sort, and reverse elements in a list. 5 | 6 | ## Features 7 | - **ADD(char)**: Adds a new element with `DATA=char` to the end of the list. 8 | - **DEL(char)**: Searches for and removes the first occurrence of an element with `DATA=char` from the list. 9 | - **PRINT**: Prints all elements in the list in their current order. 10 | - **SORT**: Sorts the list in ascending order. 11 | - **REV**: Reverses the order of the list elements. 12 | 13 | ## Input Handling 14 | - The input string, `listInput`, can contain up to 30 commands. 15 | - Commands are separated by the `~` character. 16 | - The program performs validation checks on the commands to ensure proper formatting and valid operations. 17 | 18 | ## Command Format 19 | - **ADD and DEL Commands**: Must contain exactly one character within parentheses (e.g., `ADD(a)` or `DEL(b)`). Commands with zero or multiple characters in parentheses are considered malformed and are discarded. 20 | - **Case Sensitivity**: Commands must be in uppercase letters (e.g., `PRINT` is valid, but `print` is not). 21 | - **No Spaces in Commands**: Commands must not contain spaces within the command word (e.g., `SORT` is valid, but `SO RT` is not). However, spaces adjacent to the `~` separators are tolerated. 22 | - **Examples**: 23 | - Valid: `ADD(a)~DEL(b)~PRINT~SORT~REV` 24 | - Invalid: `AD D(a)~DE L(b)~print~SO RT~REV` 25 | 26 | ## Assembly Code Structure 27 | - **Main Function**: Processes the input string, delegates commands to respective functions, and handles overall list management. 28 | - **Helper Functions**: Implement the logic for each command (ADD, DEL, PRINT, SORT, REV) and any additional necessary operations. 29 | 30 | ## Usage 31 | 1. Place the `listInput` string in the `.data` section of the RISC-V assembly code. 32 | 2. Ensure the input string follows the specified format and constraints. 33 | 3. Run the program to see the list manipulation based on the commands provided in `listInput`. 34 | 35 | ## Example Input 36 | ``` 37 | listInput: .string "ADD(a)~ADD(b)~PRINT~SORT~PRINT~REV~PRINT" 38 | ``` 39 | 40 | ## Example Output 41 | 1. **Initial Input**: `ADD(a)~ADD(b)~PRINT~SORT~PRINT~REV~PRINT` 42 | 2. **Output**: 43 | ``` 44 | a 45 | b 46 | ----- 47 | a 48 | b 49 | ----- 50 | b 51 | a 52 | ``` 53 | 54 | This README description outlines the functionality, input handling, command format, and usage of the RISC-V assembly project for processing list commands. 55 | 56 | ## Program Logic 57 | 58 | 59 | 60 | ## Test - Video Demo 61 | [![Watch the video](./assets/thumbnail.png)](./assets/tests.mp4) 62 | 63 | ## Documentation & Repository 64 | You can download the complete documentation here. The repository is available here for browsing all the project resources. 65 | -------------------------------------------------------------------------------- /_config.yml: -------------------------------------------------------------------------------- 1 | title: "RISC-V Project: Double Linked-list Simulation" 2 | -------------------------------------------------------------------------------- /_riscv_double_linked_lists.s: -------------------------------------------------------------------------------- 1 | .data 2 | 3 | # Command references used to check if the correct formats are followed. 4 | add: .string "ADD(#)" 5 | del: .string "DEL(#)" 6 | print: .string "PRINT" 7 | rev: .string "REV" 8 | sort: .string "SORT" 9 | 10 | 11 | 12 | # Various messages used within the program. 13 | space: .word 0 14 | verifying: .string "\n>> Validating operation > " 15 | executing: .string "\n>> SUCCESS. Valid function identified! \n>> Executing function ... " 16 | invalid: .string "\n>> ERROR. Invalid function! \n" 17 | added: .string "\n>> Added char = '" 18 | addedIn: .string "' in address " 19 | deleted: .string "\n>> Element found! Delete complete! \n" 20 | notFound: .string "\n>> Element not found! Command complete! \n" 21 | sorted: .string "\n>> Sorting complete!\n" 22 | printing: .string "\n>> Printing: " 23 | reversed: .string "\n>> Reversing complete!" 24 | noElem: .string "\n>> No elements available!" 25 | running: .string "\n>> Running: Linked List Simulation. \n" 26 | inputsOk: .string "\n>> Valid number of commands identified. Proceed to command verification & execution. \n" 27 | inputerror: .string "\n>> Invalid input: maximum number[30] of commands has been exceeded! \n" 28 | fine: .string "\n>> Program terminated." 29 | newLine: .string "\n" 30 | 31 | 32 | 33 | ############## TEST INPUTS ############## 34 | 35 | listInput: .string "ADD(1) ~ ADD(a) ~ ADD(a) ~ ADD(B) ~ ADD(;) ~ ADD(9) ~PRINT~SORT~PRINT~DEL(b) ~DEL(B) ~PRI~REV~PRINT" 36 | # listInput: .string "ADD(1) ~ ADD(a) ~ ADD() ~ ADD(B) ~ ADD ~ ADD(9) ~PRINT~SORT(a)~PRINT~DEL(bb) ~DEL(B) ~PRINT~REV~PRINT" 37 | # listInput: .string "" 38 | # listInput: .string "~~~" 39 | # listInput: .string "REV ~PRINT ~ SORT~DEL(2)" 40 | # listInput: .string "ADD(1)~DEL(2)~add(3)~del(4)~SORT(5)~ADD(6)~DEL(7)~add(8)~del(9)~SORT(10)~DD(11)~DEL(12)~add(13)~del(14)~SORT(15)~ADD(16)~DEL(17)~add(18)~del(19)~SORT(20)~aDD(21)~DEL(22)~add(23)~del(24)~SORT(25)~ADD(26)~DEL(27)~add(28)~del(29)~SORT(30)~add(31)" 41 | # listInput: .string "# ADD(1)~ ADD(a)~ ADD(,) ~ add(a) ~ADD(a) ~ ADD(B) ~ PRiNT ~DEL(a) ~ REV() ~ ~ DEL(A) ~ ADD(9)~ ADD()) ~ print ~ ADD(}) ~PRI~REV~PRINT ~SORT ~PRINT~ PRINvT " 42 | 43 | 44 | 45 | .text 46 | 47 | la s0, listInput # array of commands to be executed 48 | li s1, 0xFFFFFFFF # PTAIL - last element pointer 49 | li s2, 0xFFFFFFFF # PHEAD - first element pointer 50 | # s7 cmd format address 51 | li s11, 0 # listInput pointer 52 | li s10, 0 # listInput pointer value 53 | li s9, 1 # no_error [ 1 - true, 0 - false ] 54 | li s8, 0 # DATA char value for ADD & DEL 55 | li s6, 0 # cmd_status [ 0 - NULL or no valid command found, 65 - ADD, 68 - DEL, 80 - PRINT, 82 - REV, 83 - SORT ] 56 | li s5, 0x0011 # default LFSR 57 | li s4, 0 # element counter 58 | 59 | 60 | 61 | 62 | MAIN: 63 | jal msg_running 64 | 65 | verify_command_numbers: 66 | add a2, s0, zero 67 | jal func_counter # func_counter(listInput) - Returns the number of commands within the listInput. 68 | li t0, 30 69 | blt a0, t0, inputs_ok # If commands are greater than 30, interrupt the program. Else proceed executing the commands on listInput. 70 | jal msg_inputerror 71 | j end 72 | 73 | inputs_ok: jal msg_inputsOk 74 | execute_inputs: jal msg_verifying 75 | 76 | while_has_char: 77 | add t4, s0, s11 78 | lb s10, 0(t4) # Get the current value on listInput pointer. 79 | jal msg_print_data 80 | beq s10, zero, Phase4_Exec # If no char left from listInput, verify cmd_status & execute last command. 81 | beq s9, zero, Phase3_TildaCheck # If no_error == false, find tilda & execute error message 82 | bgt s6, s9, Phase2_CmdFormatCheck # If cmd_status > 1, & has a potential function, verify function format. 83 | 84 | Phase1_Ident_1st_Letter: # PHASE 1 - Verifies the first character of the command & setup the cmdAddress accordingly for reference to check if the format is correct. 85 | addi s11, s11, 1 # Set listInput pointer to 1. 86 | li t0, 1 # Set cmdAddress pointer to 1 which is the second letter of the reference array. 87 | li t1, 32 88 | beq s10, t1, while_has_char # If it encounters a ' ', a space character, return to phase1 and continue searching for a valid first letter. 89 | li t1, 65 90 | beq s10, t1, cmd_A # If it starts with 'A', set the cmdAddress to ADD(#) as the potential command to execute, then proceed to phase2. 91 | li t1, 68 92 | beq s10, t1, cmd_D # If it starts with 'D', set the cmdAddress to DEL(#) as the potential command to execute, then proceed to phase2. 93 | li t1, 80 94 | beq s10, t1, cmd_P # If it starts with 'P', set the cmdAddress to PRINT as the potential command to execute, then proceed to phase2. 95 | li t1, 82 96 | beq s10, t1, cmd_R # If it starts with 'R', set the cmdAddress to REV as the potential command to execute, then proceed to phase2. 97 | li t1, 83 98 | beq s10, t1, cmd_S # If it starts with 'S', set the cmdAddress to SORT as the potential command to execute, then proceed to phase2. 99 | li t1, 126 100 | beq s10, t1, type2_error # If it encounters a '~', a null function, send an error message & return to phase1. 101 | j type1_error # If it encounters all other invalid characters, set an error status & continue checking until tilda(~) is found. 102 | 103 | cmd_A: li s6, 65 # Set the cmd status to ADD. 104 | la s7, add # Set the cmdAddress to ADD(#) as the reference array. 105 | j while_has_char 106 | cmd_D: li s6, 68 # Set the cmd status to DEL. 107 | la s7, del # Set the cmdAddress to DEL(#) as the reference array. 108 | j while_has_char 109 | cmd_P: li s6, 80 # Set the cmd status to PRINT. 110 | la s7, print # Set the cmdAddress to PRINT as the reference array. 111 | j while_has_char 112 | cmd_R: li s6, 82 # Set the cmd status to REV. 113 | la s7, rev # Set the cmdAddress to REV as the reference array. 114 | j while_has_char 115 | cmd_S: li s6, 83 # Set the cmd status to SORT. 116 | la s7, sort # Set the cmdAddress to SORT as the reference array. 117 | j while_has_char 118 | 119 | type1_error: li s6, 0 # Set the cmd status to NULL. 120 | li s9, 0 # Set the phase tracker to 0, which signals that an error is found. 121 | j while_has_char 122 | type2_error: jal msg_error 123 | j end_exec 124 | 125 | 126 | Phase2_CmdFormatCheck: # PHASE 2 - Verifies the rest of the characters of the command using an array in cmdAddress as a reference if they follow the correct format. 127 | add t1, t0, s7 128 | lb t1, 0(t1) # Get the current value on cmdAddress pointer. 129 | beq t1, zero, Phase3_TildaCheck # If all the letters of cmdAddress are verified & corrisponds correctly, go to phase3 to look for tilda(~). 130 | addi t0, t0, 1 # Increment cmdAddress pointer by 1. 131 | addi s11, s11, 1 # Increment listInput pointer by 1. 132 | li t2, 35 133 | bne t1, t2, verify # If the character '#' is encountered on the cmdAddress, save the value from the current listInput pointer which is the DATA (input value). 134 | add s8, s10, zero # Save the DATA to s8(input value for ADD or DEL commands). 135 | j while_has_char 136 | verify: 137 | beq t1, s10 while_has_char # While the values of cmdAddress & listinput corrisponds correctly, continue verifying. 138 | li t2, 126 139 | beq s10, t2, type2_error # If the command is not fully verified & a tilda is met, then the command is invalid. Send an error message & return to phase1. 140 | j type1_error # If it encounters all other invalid characters, set an error status & continue checking until a tilda(~) is found. 141 | 142 | 143 | Phase3_TildaCheck: # PHASE 3 - Verifies the rest of the characters of the listInput until a tilda(~) is found. 144 | addi s11, s11, 1 # Increment listInput pointer by 1. 145 | li t2, 32 146 | beq s10, t2 while_has_char # If it encounters a ' ', a space character, continue checking until tilda(~) is found. 147 | li t2, 126 148 | beq s10, t2 Phase4_Exec # If tilda(~) is found, go to phase4 & execute the function. 149 | j type1_error # If it encounters all other invalid characters, set an error status & continue checking until tilda(~) is found. 150 | 151 | 152 | Phase4_Exec: 153 | bne s6, zero, execute_command 154 | bne s10, zero, type2_error # If the listInput still has other commands & an error is found, execute an error message. 155 | jal msg_error # If the last command has an error execute an error message & end the program. 156 | j end 157 | execute_command: 158 | jal msg_executing 159 | j setup&call_func # Setup the arguments & call the current correct function. 160 | end_exec: 161 | beq s10, zero, end 162 | li s9, 1 163 | li s6, 0 164 | j execute_inputs 165 | 166 | setup&call_func: 167 | li t0, 65 168 | beq s6, t0, call_ADD 169 | beq s4, zero, err_noElem 170 | li t0, 68 171 | beq s6, t0, call_DEL 172 | li t0, 80 173 | beq s6, t0, call_PRINT 174 | li t0, 82 175 | beq s6, t0, call_REV 176 | li t0, 83 177 | beq s6, t0, call_SORT 178 | j end_exec 179 | call_ADD: add a2, s8, zero # DATA 180 | add a3, s5, zero # lfsr 181 | add a4, s1, zero # PTAIL, the address of the last element. 182 | add a5, s2, zero # PHEAD, the address of the last element. 183 | jal Func_ADD 184 | addi s4, s4, 1 # Increment DATA counter by 1 185 | add s1, a0, zero # Updates the PTAIL 186 | add s5, a1, zero # Updates the SEED 187 | lw s2, 0(sp) # Updates the PHEAD 188 | addi sp, sp, 4 189 | j end_exec 190 | call_DEL: add a2, s8, zero # Set DATA as function argument. 191 | add a3, s2, zero # Set PHEAD as function argument. 192 | add a4, s1, zero # Set PTAIL as function argument. 193 | add a5, s4, zero # Set data counter as function argument. 194 | jal Func_DEL 195 | add s1, a0, zero # Updates the PTAIL 196 | add s2, a1, zero # Updates the PHEAD 197 | lw s4, 0(sp) # Updates DATA counter 198 | addi sp, sp, 4 199 | j end_exec 200 | call_PRINT: jal msg_printing 201 | add a2, s2, zero # Set PHEAD as function argument. 202 | jal Func_PRINT 203 | j end_exec 204 | call_REV: add a2, s2, zero # Set PHEAD as function argument. 205 | jal Func_REV 206 | add s2, a0, zero # Updates the PHEAD 207 | j end_exec 208 | call_SORT: add a2, s2, zero # set phead as function argument1 209 | add a3, s4, zero # set n(number of data) as function argument2 210 | jal Bubblesort 211 | jal msg_sorted 212 | j end_exec 213 | err_noElem: jal msg_noElem 214 | j end_exec 215 | 216 | # END MAIN 217 | 218 | 219 | 220 | 221 | 222 | 223 | 224 | 225 | 226 | 227 | 228 | # ================================================================================== 229 | # - @name func_counter(char[] listInput) 230 | # - @descript. Counts the number of commands within the listInput. 231 | # - @args char[] a2 - listInput 232 | # - @return int a0 - number_of_commands 233 | 234 | func_counter: 235 | li t0, 0 236 | li t1, 126 237 | li t3, 0 238 | funz_counter_while: 239 | add t2, a2, t0 240 | lb t2, 0(t2) 241 | beq t2, zero, funz_counter_end 242 | addi t0, t0, 1 243 | bne t2, t1, funz_counter_while 244 | addi t3, t3, 1 245 | j funz_counter_while 246 | funz_counter_end: 247 | add a0, t3, zero 248 | jr ra 249 | 250 | 251 | 252 | 253 | # ================================================================================== 254 | # - @name Func_ADD(char DATA, byte lfsr, byte PTAIL, byte PHEAD) 255 | # - @descript. Inserts the DATA char to the linked list. 256 | # - @args char a2 - DATA 257 | # - @args byte a3 - lfsr 258 | # - @args byte a4 - PTAIL 259 | # - @args byte a5 - PHEAD 260 | # - @return byte a0 - new_PTAIL 261 | # - @return byte a1 - new_lfsr 262 | # - @return byte sp - new_PHEAD 263 | 264 | Func_ADD: 265 | addi sp, sp, -8 266 | sw a2, 4(sp) # Save DATA to the stack memory. 267 | sw ra, 0(sp) # Save return address to the stack memory. 268 | 269 | add a2, a3, zero # Setup lfsr argument. 270 | jal Get_new_address # Call Get_new_address(lfsr) function. 271 | add t0, a0, zero # New address where DATA must be stored. 272 | add t3, a1, zero # New lfsr 273 | lw t2, 4(sp) # Retrieve DATA from the stack memory. 274 | 275 | insertData: 276 | li t1, 0xFFFFFFFF 277 | sw a4, 0(t0) # Store PBACK 278 | sb t2, 4(t0) # Store DATA 279 | sw t1, 5(t0) # Store PAHEAD 280 | 281 | add a0, t0, zero 282 | jal msg_add1 283 | 284 | beq a4, t1, setHead # IF PTAIL == 0xFFFFFFFF, set PHEAD. 285 | sw t0, 5(s1) # Update the PAHEAD of the previous element with the new address of the new element. 286 | sw a5, 4(sp) # return value - PHEAD 287 | j end_add 288 | setHead: 289 | sw t0, 4(sp) # return value - PHEAD 290 | 291 | end_add: 292 | add a0, t0, zero # return value - PTAIL 293 | add a1, t3, zero # return value - lfsr 294 | lw ra, 0(sp) 295 | addi sp, sp, 4 296 | jr ra 297 | 298 | 299 | 300 | 301 | # ================================================================================== 302 | # - @name Get_new_address(byte lfsr) 303 | # - @descript. Generates a new memory address. 304 | # - @args byte a2 - lfsr 305 | # - @return byte a0 - new_address 306 | # - @return byte a1 - new_LFSR 307 | 308 | Get_new_address: 309 | add t0, a2, zero 310 | 311 | calculate_LFSR: 312 | srli t1, t0, 2 # lfsr >> 2 313 | xor t2, t0, t1 # newBit = lfsr >> 0 XOR lfsr >> 2 314 | srli t1, t0, 3 # lfsr >> 3 315 | xor t2, t2, t1 # newBit = newBit XOR lfsr >> 3 316 | srli t1, t0, 5 # lfsr >> 5 317 | xor t2, t2, t1 # newBit = newBit XOR lfsr >> 5 318 | slli t2, t2, 15 # newBit = newBit << 15 319 | srli t1, t0, 1 # lfsr >> 1 320 | or t0, t2, t1 # newBit = newBit OR lfsr >> 2 321 | 322 | trim_16bit: 323 | li t1, 0xFFFF0000 324 | or t0, t0, t1 325 | xor t0, t0, t1 326 | 327 | new_address: 328 | li t1, 0x00010000 329 | or t2, t1, t0 # newAddress = 0x001000 OR 16-bit-LFSR 330 | 331 | check_address: 332 | lb t4, 9(t2) 333 | bne t4, zero, calculate_LFSR 334 | lw t4, 0(t2) 335 | beq t4, zero, end_get_new_address 336 | j calculate_LFSR 337 | 338 | end_get_new_address: 339 | add a0, t2, zero # return value - new address 340 | add a1, t0, zero # return value - new LFSR 341 | jr ra 342 | 343 | 344 | 345 | 346 | # ================================================================================== 347 | # - @name Func_DEL(char DATA, byte PHEAD, byte PTAIL, int element_number) 348 | # - @descript. Find the first element which corrisponds to the DATA within the linked list & eliminates it. 349 | # - @args char a2 - DATA 350 | # - @args byte a3 - PHEAD 351 | # - @args byte a4 - PTAIL 352 | # - @args int a5 - data_counter 353 | # - @return byte a0 - new_PTAIL 354 | # - @return byte a1 - new_PHEAD 355 | # - @return int sp - new_value_data_counter 356 | 357 | Func_DEL: 358 | addi sp, sp, -4 359 | sw ra, 0(sp) 360 | add t0, a3, zero # PHEAD - the address of the first element. 361 | 362 | fetchData: 363 | lb t1, 4(t0) 364 | bne t1, a2, checkNext 365 | 366 | savePointers: 367 | lw t2, 0(t0) 368 | lw t3, 5(t0) 369 | 370 | deleteChar: 371 | sw zero, 0(t0) 372 | sb zero, 4(t0) 373 | sw zero, 5(t0) 374 | 375 | li t4, 0xFFFFFFFF 376 | 377 | fixPHead: 378 | bne t3, t4, fixPTail 379 | sw t4, 5(t2) # beq t3 FFFF 380 | add t0, t2, zero 381 | add t1, a3, zero 382 | j _deleted 383 | 384 | fixPTail: 385 | bne t2, t4, fixPHeadTail 386 | sw t4, 0(t3) # beq t2 FFFF 387 | add t0, a4, zero 388 | add t1, t3, zero 389 | j _deleted 390 | 391 | fixPHeadTail: 392 | add t5, t2, zero 393 | add t6, t3, zero 394 | sw t6, 5(t2) # bne t2 FFFF 395 | sw t5, 0(t3) # bne t3 FFFF 396 | add t0, a4, zero 397 | add t1, a3, zero 398 | j _deleted 399 | 400 | checkNext: 401 | li t4, 0xFFFFFFFF 402 | lw t1, 5(t0) 403 | beq t1, t4, char_not_found 404 | add t0, t1, zero 405 | j fetchData 406 | 407 | char_not_found: 408 | jal msg_notFound 409 | add a0, a4, zero # return value - PTAIL 410 | add a1, a3, zero # return value - PHEAD 411 | j _end_del 412 | 413 | _deleted: 414 | jal msg_deleted 415 | addi a5, a5, -1 416 | add a0, t0, zero # return value - PTAIL 417 | add a1, t1, zero # return value - PHEAD 418 | 419 | _end_del: 420 | lw ra, 0(sp) 421 | sw a5, 0(sp) # return value - data_counter 422 | jr ra 423 | 424 | 425 | 426 | 427 | # ================================================================================== 428 | # - @name Func_PRINT(byte PHEAD) 429 | # - @descript. Prints every element of the linked list to the console. 430 | # - @args byte a2 - PHEAD 431 | # - @return null 432 | 433 | Func_PRINT: 434 | addi sp, sp, -4 435 | sw ra, 0(sp) 436 | 437 | add t0, a2, zero 438 | li t2, 0xFFFFFFFF 439 | 440 | print_data: 441 | lb a0, 4(t0) 442 | li a7, 11 443 | ecall 444 | 445 | lw t1, 5(t0) 446 | beq t1, t2, end_print 447 | add t0, t1, zero 448 | j print_data 449 | 450 | end_print: 451 | jal msg_newline 452 | lw ra, 0(sp) 453 | addi sp, sp, 4 454 | jr ra 455 | 456 | 457 | 458 | 459 | # ================================================================================== 460 | # - @name Func_REV(byte PHEAD) 461 | # - @descript. Changes the position of every element of the linked list in reverse order by switching its pointers. 462 | # - @args byte a2 - PHEAD 463 | # - @return byte a0 - new_PHEAD 464 | 465 | Func_REV: 466 | addi sp, sp, -4 467 | sw ra, 0(sp) 468 | 469 | add t0, a2, zero 470 | 471 | load_pointers_to_temp: 472 | lw t2, 0(t0) 473 | lw t3, 5(t0) 474 | 475 | swap_pointers: 476 | sw t3, 0(t0) 477 | sw t2, 5(t0) 478 | 479 | li t4, 0xFFFFFFFF 480 | beq t3, t4, rev_end 481 | add t0, t3, zero 482 | j load_pointers_to_temp 483 | 484 | rev_end: 485 | jal msg_reversed 486 | add a0, t0, zero # return value - phead address 487 | lw ra, 0(sp) 488 | addi sp, sp, 4 489 | jr ra 490 | 491 | 492 | 493 | 494 | # ================================================================================== 495 | # - @name Bubblesort(byte PHEAD, int data_counter) 496 | # - @descript. Sorts the elements of the linked list. 497 | # - @args byte a2 - PHEAD 498 | # - @args int a3 - data_counter 499 | # - @return null 500 | 501 | Bubblesort: # bubblesort(arr[], n) 502 | li t5, 1 503 | 504 | base_case: # n==1 505 | bne a3, t5, non_base_case 506 | jr ra 507 | 508 | non_base_case: # n>1 509 | li t6, 0 # i=0 510 | addi t0, a3, -1 # n-1 511 | 512 | while: 513 | beq t0, t6, recursive_call 514 | 515 | lb t2, 4(a2) # Get arr[i] 516 | lw t3, 5(a2) 517 | lb t3, 4(t3) # Get arr[i+1] 518 | 519 | addi sp, sp, -12 520 | sw t0, 8(sp) 521 | sw a2, 4(sp) 522 | sw ra, 0(sp) 523 | 524 | add a2, t2, zero 525 | jal Categorize # Perform categorize(arr[i]) function. 526 | add t4, a0, zero # category(arr[i]) value. 527 | 528 | add a2, t3, zero 529 | jal Categorize # Perform categorize(arr[i+1]) function. 530 | add t5, a0, zero # category(arr[i+1]) value. 531 | 532 | lw ra, 0(sp) 533 | lw a2, 4(sp) 534 | lw t0, 8(sp) 535 | addi sp, sp, 12 536 | 537 | beq t4, t5 check_ascii # If category(arr[i]) == category(arr[i+1]), compare their ascii values. 538 | bgt t4, t5 swap # If category(arr[i]) > category(arr[i+1]), then swap values. 539 | j sort_next # Otherwise category(arr[i]) < category(arr[i+1]), no need to swap. Proceed to next pair. 540 | 541 | check_ascii: 542 | bgt t2, t3 swap # If arr[i] > arr[i+1], then swap values. 543 | j sort_next # Otherwise arr[i] < arr[i+1], no need to swap. Proceed to next pair. 544 | 545 | swap: 546 | sb t3, 4(a2) 547 | lw t4, 5(a2) 548 | sb t2, 4(t4) 549 | 550 | sort_next: 551 | addi t6, t6, 1 552 | lw a2, 5(a2) 553 | j while 554 | 555 | recursive_call: 556 | add a2, s2, zero # head pointer 557 | addi a3, a3, -1 # n-1 558 | 559 | addi sp, sp, -4 560 | sw ra, 0(sp) 561 | 562 | jal Bubblesort # Bubblesort(arr[], n) 563 | 564 | lw ra, 0(sp) 565 | addi sp, sp, 4 566 | jr ra 567 | 568 | 569 | 570 | # ================================================================================== 571 | # - @name Categorize(char DATA) 572 | # - @descript. Returns an int value which represents the category of the char [ 1 - spec.char, 2 - numbers, 3 - min.alpha., 4 - maus.alpha.] 573 | # - @args char a2 - DATA 574 | # - @return int a0 - category 575 | 576 | Categorize: 577 | li t0, 48 578 | blt a2, t0, cat1 579 | li t0, 58 580 | blt a2, t0, cat2 581 | li t0, 65 582 | blt a2, t0, cat1 583 | li t0, 91 584 | blt a2, t0, cat4 585 | li t0, 97 586 | blt a2, t0, cat1 587 | li t0, 123 588 | blt a2, t0, cat3 589 | cat1: li a0, 1 590 | jr ra 591 | cat2: li a0, 2 592 | jr ra 593 | cat3: li a0, 3 594 | jr ra 595 | cat4: li a0, 4 596 | jr ra 597 | 598 | 599 | 600 | 601 | ################################################ 602 | ############## MESSAGES ############## 603 | ################################################ 604 | 605 | msg_add1: add t0, a0, zero 606 | la a0, added 607 | li a7, 4 608 | ecall 609 | addi a0, s8, 0 610 | li a7, 11 611 | ecall 612 | la a0, addedIn 613 | li a7, 4 614 | ecall 615 | addi a0, t0, 0 616 | li a7, 34 617 | ecall 618 | lw a0, newLine 619 | li a7, 11 620 | ecall 621 | jr ra 622 | 623 | msg_verifying: la a0, verifying 624 | li a7, 4 625 | ecall 626 | jr ra 627 | 628 | msg_error: la a0, invalid 629 | li a7, 4 630 | ecall 631 | jr ra 632 | 633 | msg_executing: la a0, executing 634 | li a7, 4 635 | ecall 636 | jr ra 637 | 638 | msg_sorted: la a0, sorted 639 | li a7, 4 640 | ecall 641 | jr ra 642 | 643 | msg_printing: la a0, printing 644 | li a7, 4 645 | ecall 646 | jr ra 647 | 648 | msg_print_data: li t4, 126 649 | beq s10, t4, end_msg_print_data 650 | addi a0, s10, 0 651 | li a7, 11 652 | ecall 653 | end_msg_print_data: 654 | jr ra 655 | 656 | msg_deleted: la a0, deleted 657 | li a7, 4 658 | ecall 659 | jr ra 660 | 661 | msg_notFound: la a0, notFound 662 | li a7, 4 663 | ecall 664 | jr ra 665 | 666 | msg_noElem: la a0, noElem 667 | li a7, 4 668 | ecall 669 | lw a0, newLine 670 | li a7, 11 671 | ecall 672 | jr ra 673 | 674 | msg_reversed: la a0, reversed 675 | li a7, 4 676 | ecall 677 | lw a0, newLine 678 | li a7, 11 679 | ecall 680 | jr ra 681 | 682 | msg_newline: lw a0, newLine 683 | li a7, 11 684 | ecall 685 | jr ra 686 | 687 | msg_inputerror: la a0, inputerror 688 | li a7, 4 689 | ecall 690 | jr ra 691 | 692 | msg_inputsOk: la a0, inputsOk 693 | li a7, 4 694 | ecall 695 | jr ra 696 | 697 | msg_running: la a0, running 698 | li a7, 4 699 | ecall 700 | jr ra 701 | 702 | 703 | 704 | 705 | end: 706 | la a0, fine 707 | li a7, 4 708 | ecall -------------------------------------------------------------------------------- /assets/riscv.gif: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/ngljcb/px-riscv-double-linkedlist/2aee4159ee81da987af2353f4ff98eeed7ea41e7/assets/riscv.gif -------------------------------------------------------------------------------- /assets/tests.mp4: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/ngljcb/px-riscv-double-linkedlist/2aee4159ee81da987af2353f4ff98eeed7ea41e7/assets/tests.mp4 -------------------------------------------------------------------------------- /assets/thumbnail.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/ngljcb/px-riscv-double-linkedlist/2aee4159ee81da987af2353f4ff98eeed7ea41e7/assets/thumbnail.png -------------------------------------------------------------------------------- /documentation.pdf: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/ngljcb/px-riscv-double-linkedlist/2aee4159ee81da987af2353f4ff98eeed7ea41e7/documentation.pdf --------------------------------------------------------------------------------