clean up runtime

This commit is contained in:
nub31
2025-06-10 22:22:49 +02:00
parent 9f48f2cd9b
commit 299e06a03e
6 changed files with 40 additions and 50 deletions

View File

@@ -2,9 +2,10 @@
.extern main
.section .text
.globl _start
.global _start
_start:
mov rdi, rsp
# main([]^string): i64
call main
mov rdi, rax
mov rax, 60

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@@ -1,24 +1,20 @@
.intel_syntax noprefix
.section .text
# Memory copy function
# Arguments: rdi = destination, rsi = source, rdx = count
# Returns: rdi (original destination pointer)
.globl nub_memcpy
# func nub_memcpy(destination: ^u8, source: ^u8, count: u64): ^u8
.global nub_memcpy
nub_memcpy:
push rdi # Save original destination for return value
mov rcx, rdx # Load count into counter register
# Handle zero count case
push rdi
mov rcx, rdx
test rcx, rcx
jz .done
# Simple byte-by-byte copy (no overlap handling)
.loop:
mov al, BYTE PTR [rsi] # Load byte from source
mov BYTE PTR [rdi], al # Store byte to destination
inc rsi # Move to next source byte
inc rdi # Move to next destination byte
dec rcx # Decrement counter
jnz .loop # Continue if counter not zero
.done:
pop rax # Return original destination pointer
jz memcpy_done
memcpy_loop:
mov al, BYTE PTR [rsi]
mov BYTE PTR [rdi], al
inc rsi
inc rdi
dec rcx
jnz memcpy_loop
memcpy_done:
pop rax
ret

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@@ -1,22 +1,19 @@
.intel_syntax noprefix
.section .text
# Memory set function
# Arguments: rdi = destination pointer, rsi = value (byte), rdx = count
# Returns: rdi (original destination pointer)
.globl nub_memset
# func nub_memset(destination: ^u8, value: i8, count: u64): ^u8
.global nub_memset
nub_memset:
push rdi # Save original destination for return value
mov rcx, rdx # Load count into counter register
mov al, sil # Move byte value to al (lower 8 bits of rsi)
# Handle zero count case
push rdi
mov rcx, rdx
mov al, sil
test rcx, rcx
jz .done
.loop:
mov BYTE PTR [rdi], al # Store byte at current position
inc rdi # Move to next byte
dec rcx # Decrement counter
jnz .loop # Continue if counter not zero
.done:
pop rax # Return original destination pointer
jz memset_done
memset_loop:
mov BYTE PTR [rdi], al
inc rdi
dec rcx
jnz memset_loop
memset_done:
pop rax
ret

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@@ -1,10 +1,8 @@
.intel_syntax noprefix
.section .text
# Panic function with message
# Arguments: rdi = message (*char), rsi = message length (long)
# Remarks: exits the program
.globl nub_panic
# func nub_panic(message: ^u8, message_length: u64): void
.global nub_panic
nub_panic:
mov rdx, rsi
mov rsi, rdi

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@@ -1,24 +1,22 @@
.intel_syntax noprefix
.section .text
# String comparison function null-terminated strings
# Arguments: rdi = lhs (*char), rsi = rhs (*char)
# Returns: 1 if equal, else 0
.globl nub_strcmp
# func nub_strcmp(lhs: ^u8, rhs: ^u8): bool
.global nub_strcmp
nub_strcmp:
xor rdx, rdx
.loop:
strcmp_loop:
mov al, BYTE PTR [rsi + rdx]
mov bl, BYTE PTR [rdi + rdx]
inc rdx
cmp al, bl
jne .not_equal
jne strcmp_not_equal
cmp al, 0
je .equal
jmp .loop
.not_equal:
je strcmp_equal
jmp strcmp_loop
strcmp_not_equal:
mov rax, 0
ret
.equal:
strcmp_equal:
mov rax, 1
ret

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@@ -1,5 +1,5 @@
.intel_syntax noprefix
.globl core_syscall
.global core_syscall
.section .text
core_syscall: