Recent questions tagged Assembly

0 votes

1.1k views

1 answer

During reading of an Intel manual book I came across the following: On processors that support Intel 64 architecture ... a 'canonical address'? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

940 views

1 answer

assembly - How to "goto" into different function in c?

Basically I am trying to simulate assembly code in C. Here is the C code: int main() { test(); main_next: ... -procedural goto in C? Thank you! See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

880 views

1 answer

assembly - Reading from memory in 8086 real mode while using 'ORG 0x0000'

I've been messing around with x86-16 assembly and running it with VirtualBox. For some reason when I read ... fault. It prints something like: See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.1k views

1 answer

assembly - X86 instructions to power off computer in real mode?

Is there any sequence of x86 instructions in real mode that will power off (not reboot) the machine? I have an ... mode or 64-bit long mode. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.0k views

1 answer

assembly - How does one do integer (signed or unsigned) division on ARM?

I'm working on Cortex-A8 and Cortex-A9 in particular. I know that some architectures don't come with integer ... best solution? Cheers! = ) See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.1k views

1 answer

assembly - What is callq instruction?

I have some gnu assembler code for the x86_64 architecture generated by a tool and there are these instructions: movq ... Where can I find them? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.1k views

1 answer

assembly - How to write to the console in fasm?

I'm exceptionally new to assembly. I only picked it up yesterday and I've looked through many examples and still ... it in my own way. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.1k views

1 answer

assembly - What does an equals sign = on the right side of a LDR instruction in ARM mean?

Been googling this for a while but i can't find any documentation relating to this. I've been trying to ... me understand this? Thank you! See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

793 views

1 answer

assembly - How does the CPU/assembler know the size of the next instruction?

For the sake of example, imagine I was building a virtual machine. I have a byte array and a while ... particular instruction is more important. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.2k views

1 answer

assembly - Why would we use addiu instead of addi?

In MIPS assembly, what is the benefit of using addiu over addi? Isn't addiu unsigned (and will ruin our calculations?) See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

763 views

1 answer

assembly - x86 32 bit opcodes that differ in x86-x64 or entirely removed

I've looked up Wikipedia for x86 backward compatibility in x86-x64 and it says: x86-64 is fully backwards compatible ... 32 bit in x86-x64. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

895 views

1 answer

assembly - Is reserving stack space necessary for functions less than four arguments?

Just started learning x64 assembly and I have a question about functions, arguments, and the stack. As far as ... is it just a recommendation? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.4k views

1 answer

assembly - View disassembly in XCode 4 (or Xcode 5 or Xcode 6)

I'm having trouble finding much in the way of information about the new XCode layout. How can I view the disassembly ... than just the C++ code? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

968 views

1 answer

assembly - How can ARM's MOV instruction work with a large number as the second operand?

I just begin to study ARM assembly language, and am not clear about how to use MOV to transfer an ... range according to the specification? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.6k views

1 answer

assembly - Linking C with NASM

I have a NASM file and a C file. How do I call a function in the C file from the NASM file? How do ... function from the C file? Many Thanks DD See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.5k views

1 answer

assembly - In x86 what's difference between "test eax,eax" and "cmp eax,0"

Is test eax, eax more efficient than cmp eax, 0? Is there any case that the test eax, eax is necessary ... eax, 0 doesn't fulfill requirement? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

867 views

1 answer

assembly - What is register %eiz?

In the following assembly code that I dumped out using objdump: lea 0x0(%esi,%eiz,1),%esi What is register ... does the preceding code mean? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

929 views

1 answer

assembly - Converting very simple ARM instructions to binary/hex

I've been trying to use this page as well as various other guides to figure out how to express very simple ... Thanks in advance for your help. See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.0k views

1 answer

assembly - What's the purpose of the rotate instructions (ROL, RCL on x86)?

I always wondered what's the purpose of the rotate instructions some CPUs have (ROL, RCL on x86, for example ... added to the instructions set? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.6k views

1 answer

assembly - ret, retn, retf - how to use them

I have the following asm code: ; int __stdcall wWinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPWSTR ... optional parameter, nBytes? See Question&Answers more detail:os...

asked Oct 24, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.0k views

1 answer

assembly - What's the purpose of the CIL nop opcode?

I'm going through MSIL and noticing there are a lot of nop instructions in the MSIL. The MSDN article ... the question originally asked about.) See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

861 views

1 answer

assembly - Writing my own BIOS

I'm not crazy, just reinventing the wheel :D I wrote boot-loaders, mouse & keyboard mini-drivers, mini OS ... I start editing my current BIOS? See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.2k views

1 answer

assembly - Print decimal in 8086 emulator

I implemented the multiplication of two big integer in emu8086 with code as below : ; MULTIPLY N1 * N2 = RES ... ? Thanks for your advance :) See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

986 views

1 answer

assembly - Saving integers as Strings in MIPS

I was just wondering, is there any way in MIPS to store a summation of numbers as a string and later read them ... and so on. Is this possible? See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.0k views

1 answer

assembly - How to determine if ModR/M is needed through Opcodes?

I am reading the ia-32 instruction format and found that ModR/M is one byte if required, but how to ... documents which explain the details? See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

1.2k views

1 answer

assembly - Multiply numbers without using instructions MUL, IMUL, SHL, SHR, LOOP

Is it possible to calculate result of multiplication without using instructions MUL, IMUL, SHL, SHR, LOOP, JMP in x86 assembly language? See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

871 views

1 answer

assembly - Creating an x86 assembler program that converts an integer to a 16-bit binary string of 0's and 1's

As the question suggests, I have to write a MASM program to convert an integer to binary. I have tried many ... : pop ebp _intToBin ENDP END See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

0 votes

885 views

1 answer

assembly - Make previous memory stores visible to subsequent memory loads

I want to store data in a large array with _mm256_stream_si256() called in a loop. As I understood, a ... the current thread currently holds. See Question&Answers more detail:os...

asked Oct 17, 2021 in Technique[技术] by 深蓝 (71.8m points)

Categories

Just Browsing Browsing

Most popular tags