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| author | scratko <m@scratko.xyz> | 2024-03-27 22:38:51 +0300 |
|---|---|---|
| committer | scratko <m@scratko.xyz> | 2024-03-27 22:38:51 +0300 |
| commit | 21f616b5593d87d6381c1f3d67a3df0c442dba44 (patch) | |
| tree | 28eba727b41d4d6b6b273ba3f7e81a4793d56e84 /string_conversion.asm | |
| download | trigonometric-table-21f616b5593d87d6381c1f3d67a3df0c442dba44.tar.gz trigonometric-table-21f616b5593d87d6381c1f3d67a3df0c442dba44.tar.bz2 trigonometric-table-21f616b5593d87d6381c1f3d67a3df0c442dba44.zip | |
Initial commit
Diffstat (limited to 'string_conversion.asm')
| -rw-r--r-- | string_conversion.asm | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/string_conversion.asm b/string_conversion.asm new file mode 100644 index 0000000..1cef531 --- /dev/null +++ b/string_conversion.asm @@ -0,0 +1,40 @@ +global to_int + +section .text + +; +; angle translation from string to integer +; [ebp+8] is pointer to string +; eax=-1 if digit is not 0-9 +; else eax=number +; +to_int: push ebp + mov ebp, esp + sub esp, 8 ; local variables + push esi ; save esi + mov dword [ebp-4], 0 ; init number + mov dword [ebp-8], 10 ; init const + mov esi, [ebp+8] ; buffer + cld +.lp: lodsb + cmp al, 0 + je .store + cmp al, '0' + jl .error + cmp al, '9' + jg .error + sub al, '0' + xor ecx, ecx + xchg al, cl + mov eax, [ebp-4] + mul dword [ebp-8] + add eax, ecx + mov [ebp-4], eax + jmp .lp +.error: mov eax, -1 + jmp .quit +.store: mov eax, [ebp-4] +.quit: pop esi + mov esp, ebp + pop ebp + ret |