Questions related to the assembler `mov` instruction
The assembler mov instruction loads an immediate value into an register or transfers data between register and register or register and memory. See:
Questions tagged [mov]
296 questions
3
votes
1 answer
"mov" of "assembly language" meant copy or move?
Recently, I read the C++ of std::mov, and I thought of a question as the title.
Assume initial value following:
int a= 1;
int b= 2;
I think:
Situation 1,
after move (a <- b):
a= 2 , b=
b is null because moved
Situation 2,
after copy (a <-…
curlywei
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Assembly array access
I'm learning Assembly and I've got a question about array addressing. Suppose rsi holds the address of an array and I want to get the first byte of data starting at this address. Would the following two pieces of code do the job? If so, what is the…
Theta
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2 answers
Difference between MOV and MOV ptr
I don't understand the difference between MOV and MOV ptr.
For example, in this C code:
unsigned char x, y;
x = 2;
the second line in assembly is:
`MOV x, 2`
but the second line of this C code :
tabbyte[0] = 15
unsigned char tabbyte[4]
in…
IanMoone
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1 answer
FFprobe reports Invalid sample_count on very large .mov file
I have a 1.1TB ProRes 422 MOV file (a bit more than 24 hours of recording).
When running ffprobe -v error -print_format xml -select_streams v:0 -show_format -show_streams "Metadata Error.mov" I get the following:
[mov,mp4,m4a,3gp,3g2,mj2 @…
Pablo Montilla
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votes
1 answer
x86_64 - encoding a mov instruction
Encoding the x86_64 instruction mov rcx,rdx (using https://defuse.ca/online-x86-assembler.htm) outputs 48 89 D1.
Checking the op-code with this reference shows how that byte sequence encodes the instruction.
However two rows down in that table…
user1000039
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1 answer
Assembly Word ptr meaning
.data
num dd 090F0433H
.code
mov ax, @data
mov ds, ax
mov ax, word ptr num
mov bx, word ptr num+2
mov cl, byte ptr num+1
For mov ax, word ptr num, AH = 04, AL = 33.
Why? Can someone explain to me how to figure this out?
iTech Techno
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1 answer
When should one use MOVS opposed to MOV in x86 Assembly?
I've come across both of these instructions in the The Intel 64 and 32 Bit Architectures Software Developer Manual, and am simply wondering what the differences between the two are, and when I should use one of them over the other.
Mikestylz
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1 answer
Converting EXR image sequence to .MOV
I'm looking for a encoder that creates a Quicktime Movie (PhotoJpeg) from OpenEXR image sequences.
Any help would be really appreciated
krepitor
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Xuggle-Xuggler not converting .MOV or .AVI to .MP4
I have been trying to convert .MOV files to .MP4 using Xuggle. Here was my original code:
// create a media reader
IMediaReader mediaReader = ToolFactory.makeReader(path);
// create a media writer
IMediaWriter mediaWriter =…
user4775991
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3
votes
1 answer
8086 MOV instruction error while using a constant value and memory location as operands,
I was trying to use the instruction MOV [SI],00H in 8086 assembly language. But the masm assembler gave me an error saying: Operand must have size. I am unable to understand the reason behind it.
Also, is the syntax even allowed? Because while…
Harsh S. Kulshrestha
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1 answer
Send .mov file to ffmpeg via pipe (stdin)
If specify file in -i option, ffmpeg successfully handles file: http://pastebin.com/cn4w4aR2
But, if send file to ffmpeg via pipe (to stdin), i receive error stream 1, offset 0x24: partial file:
serafim@serafim:~/Downloads/mov $ cat…
Ruslan Sharipov
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1 answer
how many cpu cycle takes to execute MOV A, 5 instruction
My question is calculate how many CPU cycle takes to execute MOV A, 5 instruction. Describe each.
can anyone please explain me how this works. And the 5 is a value is it? Just explain me the main points.
As far as i know,
first,
-get the…
LekhAsh
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3
votes
1 answer
What do you mean by "byte equivalent" ?
I am bit new to assembly language and having difficulty understanding the term "byte equivalent".
It is used in the following context :-
The MOV instruction causes ambiguity at times. For example, look at the statements:
MOV EBX, [MY_TABLE] ;…
Pratik Singhal
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3
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C++ __asm Generating different bytes
In my function I use
__asm
{
mov ecx,dword ptr [0x28F1431]
mov ecx,ds:[0x28F14131]
}
which should produce the following bytes: 0x8B0D (mov ecx, dword ptr []). However the first instruction produces 0xB9 (mov ecx,0x28F14131) and the…
user2534466
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3
votes
1 answer
Detecting missing audio in MOV files
i'm curious if there is a way to detect if audio is missing or broken from a MOV video file. Recently there was a MOV file which was playable, but the audio was "missing".
I tried ffmpeg to get specific errors but it did not give me any. I only…
ibox
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