diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Day1.asm | 408 | ||||
| -rw-r--r-- | src/Day2.asm | 23 |
2 files changed, 195 insertions, 236 deletions
diff --git a/src/Day1.asm b/src/Day1.asm index 34b0361..8ba8f0e 100644 --- a/src/Day1.asm +++ b/src/Day1.asm @@ -1,57 +1,15 @@ ; Advent of Code 2025 - Day 1
-;
-; #include <stdio.h>
-; #include <stdlib.h>
-; #include <stddef.h>
-; #include <stdint.h>
-;
-; int main(void)
-; {
-; FILE* input = fopen("input/day1.txt", "r");
-;
-; int32_t angle1 = 50;
-; int32_t angle2 = 50;
-;
-; int32_t password1 = 0;
-; int32_t password2 = 0;
-;
-; char line[256];
-; while (fgets(line, sizeof(line), input))
-; {
-; int32_t direction = (line[0] == 'L') ? -1 : 1;
-; int32_t steps = atoi(line + 1);
-;
-; // part 1
-; angle1 += direction * steps;
-; angle1 %= 100;
-; if (angle1 < 0)
-; angle1 += 100;
-; if (angle1 == 0)
-; password1++;
-;
-; // part 2
-; for (int i = 0; i < steps; i++)
-; {
-; angle2 = ((angle2 + direction) % 100 + 100) % 100;
-; if (angle2 == 0)
-; password2++;
-; }
-; }
-;
-; fclose(input);
-;
-; printf("Password 1: %d\n", password1);
-; printf("Password 2: %d\n", password2);
-; }
+bits 64
+default rel
global _start
-%define SYS_EXIT 1
-%define SYS_READ 3
-%define SYS_WRITE 4
-%define SYS_OPEN 5
-%define SYS_CLOSE 6
+%define SYS_EXIT 60
+%define SYS_READ 0
+%define SYS_WRITE 1
+%define SYS_OPEN 2
+%define SYS_CLOSE 3
%define O_RDONLY 0
%define STDOUT 1
@@ -79,280 +37,278 @@ section .text _start:
; open file
- mov eax, SYS_OPEN
- mov ebx, inputPath
- mov ecx, O_RDONLY
- int 0x80
+ mov rax, SYS_OPEN
+ mov rdi, inputPath
+ mov rsi, O_RDONLY
+ xor rdx, rdx
+ syscall
- mov esi, eax ; fd in ESI
- mov dword [lineLen], 0 ; no chars in current line yet
+ mov r12, rax ; fd in R12
+ mov dword [lineLen], 0 ; no chars in current line yet
ReadLoop:
; read up to 4096 bytes
- mov eax, SYS_READ
- mov ebx, esi
- mov ecx, buffer
- mov edx, 4096
- int 0x80
+ mov rax, SYS_READ
+ mov rdi, r12
+ mov rsi, buffer
+ mov rdx, 4096
+ syscall
- cmp eax, 0
- jle EOF ; <=0 -> EOF or error
+ cmp rax, 0
+ jle EOF ; <=0 -> EOF or error
- mov edi, buffer ; scan pointer
- mov ebp, eax ; bytes remaining in this chunk
+ mov rdi, buffer ; scan pointer
+ mov rbp, rax ; bytes remaining in this chunk
ScanChunk:
- cmp ebp, 0
- je ReadLoop ; chunk done, read next
+ cmp rbp, 0
+ je ReadLoop ; chunk done, read next
- mov al, [edi]
+ mov al, [rdi]
; windows can be a fucking bitch
; handle (CR) -> just skip
- cmp al, 13
- je SkipCR
+ cmp al, 13
+ je SkipCR
; handle LF (10) -> end of line
- cmp al, 10
- je EndOfLine
+ cmp al, 10
+ je EndOfLine
; normal character -> append to lineBuffer if space left
- mov edx, [lineLen]
- cmp edx, 255 ; leave 1 byte for NULL
- jae SkipStore ; ignore extra characters if too long
- mov [lineBuffer+edx], al
- inc edx
- mov [lineLen], edx
+ mov edx, [lineLen]
+ cmp edx, 255 ; leave 1 byte for NULL
+ jae SkipStore ; ignore extra characters if too long
+ mov [lineBuffer+rdx], al
+ inc edx
+ mov [lineLen], edx
SkipStore:
- inc edi
- dec ebp
- jmp ScanChunk
+ inc rdi
+ dec rbp
+ jmp ScanChunk
SkipCR:
- inc edi
- dec ebp
- jmp ScanChunk
+ inc rdi
+ dec rbp
+ jmp ScanChunk
EndOfLine:
; terminate current line
- mov edx, [lineLen]
- mov byte [lineBuffer+edx], 0
+ mov edx, [lineLen]
+ mov byte [lineBuffer+rdx], 0
; if line isn't empty, process it
- cmp edx, 0
- je LineDone
+ cmp edx, 0
+ je LineDone
- push esi
- push edi
- mov esi, lineBuffer
- call HandleLine
- pop edi
- pop esi
+ push rdi
+ mov rsi, lineBuffer
+ call HandleLine
+ pop rdi
LineDone:
- mov dword [lineLen], 0 ; reset line length
- inc edi
- dec ebp
- jmp ScanChunk
+ mov dword [lineLen], 0 ; reset line length
+ inc rdi
+ dec rbp
+ jmp ScanChunk
; process last line if not newline-terminated, then print result
EOF:
; if there is a partial line at EOF, process it
- mov edx, [lineLen]
- cmp edx, 0
- jle PrintResults
- mov byte [lineBuffer+edx], 0
+ mov edx, [lineLen]
+ cmp edx, 0
+ jle PrintResults
+ mov byte [lineBuffer+rdx], 0
- push esi
- mov esi, lineBuffer
- call HandleLine
- pop esi
+ mov rsi, lineBuffer
+ call HandleLine
PrintResults:
- mov ecx, label1
- call PrintString
- mov eax, [password1]
- call PrintInt
+ mov rcx, label1
+ call PrintString
+ mov eax, [password1]
+ call PrintInt
; newline
- mov eax, SYS_WRITE
- mov ebx, STDOUT
- mov ecx, newline
- mov edx, 1
- int 0x80
+ mov rax, SYS_WRITE
+ mov rdi, STDOUT
+ mov rsi, newline
+ mov rdx, 1
+ syscall
- mov ecx, label2
- call PrintString
- mov eax, [password2]
- call PrintInt
+ mov rcx, label2
+ call PrintString
+ mov eax, [password2]
+ call PrintInt
; new linhe
- mov eax, SYS_WRITE
- mov ebx, STDOUT
- mov ecx, newline
- mov edx, 1
- int 0x80
+ mov rax, SYS_WRITE
+ mov rdi, STDOUT
+ mov rsi, newline
+ mov rdx, 1
+ syscall
- mov eax, SYS_CLOSE
- mov ebx, esi
- int 0x80
- mov eax, SYS_EXIT
- xor ebx, ebx
- int 0x80
+ mov rax, SYS_CLOSE
+ mov rdi, r12
+ syscall
+ mov rax, SYS_EXIT
+ xor rdi, rdi
+ syscall
-; Handle one line: ESI -> "L123" or "R45"
+; Handle one line: RSI -> "L123" or "R45"
HandleLine:
- mov al, [esi]
- cmp al, 'L'
- je .left
- mov ebx, 1 ; direction = +1 for 'R' or anything else
- jmp .after
+ mov al, [rsi]
+ cmp al, 'L'
+ je .left
+ mov ebx, 1 ; direction = +1 for 'R' or anything else
+ jmp .after
.left:
- mov ebx, -1 ; direction = -1 for 'L'
+ mov ebx, -1 ; direction = -1 for 'L'
.after:
- inc esi ; skip 'L' or 'R'
- call ParseInt ; EAX = steps
- mov ecx, eax
+ inc rsi ; skip 'L' or 'R'
+ call ParseInt ; EAX = steps
+ mov ecx, eax
; Part 1
P1_Start:
- mov eax, ecx
- imul eax, ebx
- add eax, [angle1]
- call NormalizeAngle
- mov [angle1], eax
- cmp eax, 0
- jne P2_Start
- mov edi, password1
- mov edx, [edi]
- inc edx
- mov [edi], edx
+ mov eax, ecx
+ imul eax, ebx
+ add eax, [angle1]
+ call NormalizeAngle
+ mov [angle1], eax
+ cmp eax, 0
+ jne P2_Start
+ mov rdi, password1
+ mov edx, [rdi]
+ inc edx
+ mov [rdi], edx
; Part 2
P2_Start:
- mov edi, password2
+ mov rdi, password2
.loop:
- test ecx, ecx
- jle P2_Exit
- dec ecx
+ test ecx, ecx
+ jle P2_Exit
+ dec ecx
- mov eax, [angle2]
- call UpdateAngleCount
- mov [angle2], eax
+ mov eax, [angle2]
+ call UpdateAngleCount
+ mov [angle2], eax
- jmp .loop
+ jmp .loop
P2_Exit:
ret
; normalize eax to 0..99
NormalizeAngle:
- cmp eax, 0
- jl .add
- cmp eax, 100
- jl .done
- sub eax, 100
- jmp NormalizeAngle
+ cmp eax, 0
+ jl .add
+ cmp eax, 100
+ jl .done
+ sub eax, 100
+ jmp NormalizeAngle
.add:
- add eax, 100
- jmp NormalizeAngle
+ add eax, 100
+ jmp NormalizeAngle
.done:
ret
-; eax = angle, ebx = direction, edi = password counter addr
+; eax = angle, ebx = direction, rdi = password counter addr
UpdateAngleCount:
- add eax, ebx
- call NormalizeAngle
+ add eax, ebx
+ call NormalizeAngle
- cmp eax, 0
- jne .done
- mov edx, [edi]
- inc edx
- mov [edi], edx
+ cmp eax, 0
+ jne .done
+ mov edx, [rdi]
+ inc edx
+ mov [rdi], edx
.done:
ret
; parse ASCII integer into EAX
ParseInt:
- xor eax, eax ; result = 0
+ xor eax, eax ; result = 0
.parseLoop:
- mov dl, [esi]
- cmp dl, '0'
- jl .done
- cmp dl, '9'
- jg .done
+ mov dl, [rsi]
+ cmp dl, '0'
+ jl .done
+ cmp dl, '9'
+ jg .done
- sub dl, '0' ; digit value 0..9
- movzx edx, dl
+ sub dl, '0' ; digit value 0..9
+ movzx edx, dl
- imul eax, eax, 10 ; result *= 10
- add eax, edx ; result += digit
+ imul eax, eax, 10 ; result *= 10
+ add eax, edx ; result += digit
- inc esi
- jmp .parseLoop
+ inc rsi
+ jmp .parseLoop
.done:
ret
PrintInt:
- mov edi, numberBuffer+15 ; write digits from the end
- mov byte [edi], 0 ; terminator
- dec edi
+ mov edi, numberBuffer+15 ; write digits from the end
+ mov byte [rdi], 0 ; terminator
+ dec rdi
- cmp eax, 0
- jne .convert
- mov byte [edi], '0'
- jmp .finish
+ cmp eax, 0
+ jne .convert
+ mov byte [rdi], '0'
+ jmp .finish
.convert:
; we will repeatedly compute:
; q = eax / 10
; r = eax % 10
; using only subtraction
.nextDigit:
- mov edx, eax ; tmp = current value
- mov ecx, 0 ; q = 0
+ mov edx, eax ; tmp = current value
+ mov ecx, 0 ; q = 0
- cmp edx, 10 ; if < 0, q=0, r=edx
- jb .lastDigit
+ cmp edx, 10 ; if < 0, q=0, r=edx
+ jb .lastDigit
.subLoop:
- sub edx, 10
- inc ecx ; q++
- cmp edx, 10
- jae .subLoop ; while tmp >= 10
+ sub edx, 10
+ inc ecx ; q++
+ cmp edx, 10
+ jae .subLoop ; while tmp >= 10
.lastDigit:
; now:
; ecx = quotient
; edx = remainder (0..9)
- add dl, '0'
- mov [edi], dl ; store digit
- dec edi
- mov eax, ecx ; eax = quotient
- test eax, eax
- jnz .nextDigit ; more digits to extract?
+ add dl, '0'
+ mov [rdi], dl ; store digit
+ dec rdi
+ mov eax, ecx ; eax = quotient
+ test eax, eax
+ jnz .nextDigit ; more digits to extract?
- inc edi ; move to first digit
+ inc rdi ; move to first digit
.finish:
- mov eax, SYS_WRITE
- mov ebx, STDOUT
- mov ecx, edi
- mov edx, numberBuffer+15
- sub edx, edi ; length
- int 0x80
+ mov rax, SYS_WRITE
+ mov rsi, rdi ; buffer pointer
+ mov rdi, STDOUT
+ mov rdx, numberBuffer+15
+ sub rdx, rsi ; length
+ syscall
ret
PrintString:
- push ecx
- push edx
- mov edx, 0
+ push rcx
+ push rdx
+ mov rdx, 0
.count:
- cmp byte [ecx+edx], 0
- je .doneCount
- inc edx
- jmp .count
+ cmp byte [rcx+rdx], 0
+ je .doneCount
+ inc rdx
+ jmp .count
.doneCount:
- mov eax, SYS_WRITE
- mov ebx, STDOUT
- int 0x80
+ mov rax, SYS_WRITE
+ mov rdi, STDOUT
+ mov rsi, rcx
+ syscall
- pop edx
- pop ecx
+ pop rdx
+ pop rcx
ret
diff --git a/src/Day2.asm b/src/Day2.asm index d524d7c..7e154da 100644 --- a/src/Day2.asm +++ b/src/Day2.asm @@ -1,9 +1,12 @@ ; Advent of Code 2025 - Day 2 +bits 64 +default rel + global _start -%define SYS_EXIT 1 -%define SYS_WRITE 4 +%define SYS_EXIT 60 +%define SYS_WRITE 1 %define STDOUT 1 @@ -13,12 +16,12 @@ section .data section .text _start: - mov eax, SYS_WRITE - mov ebx, STDOUT - mov ecx, message - mov edx, length - int 0x80 + mov rax, SYS_WRITE + mov rdi, STDOUT + mov rsi, message + mov rdx, length + syscall - mov eax, SYS_EXIT - xor ebx, ebx - int 0x80 + mov rax, SYS_EXIT + xor rdi, rdi + syscall |