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A comment on AT&T Syntax versus Intel Syntax. Parent comment

Re:AT&T Syntax versus Intel Syntax by masklinn on Sunday November 13, 2022 @02:42PM (#33586574)
> They are using a classic dollar sign for assignment

They're using a dollar sign for immediates.

As if you can't notice that it's a number.

    addl $4, %eax
that's 3 different completely unnecessary symbols for things which are not ambiguous in the first place:

- the operation width is provided by the registry

- a number is an immediate

- a register is named

Hence the much less noisy Intel syntax:

    add eax, 4
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Re:AT&T Syntax versus Intel Syntax by matja on Sunday November 13, 2022 @02:54PM (#33586673)
addl is not necessary if it is not ambiguous

    add $4, %eax
- is fine

Compare with

    add 4, %eax
The "less noisy" Intel syntax becomes:

    add eax, DWORD PTR [4]
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Re:AT&T Syntax versus Intel Syntax by __init on Sunday November 13, 2022 @03:48PM (#33587181)
Most assemblers for Intel syntax will let you write:

    add eax, [4]
if you desire. Indeed, many disassemblers will follow suit in unambiguous cases. IDA, for example, does this.
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Re:AT&T Syntax versus Intel Syntax by colejohnson66 on Sunday November 13, 2022 @05:03PM (#33587855)
This. The only time “DWORD PTR” is required is when (1) you’re working with old assemblers, or (2) you’re using a memory operand with an immediate:

    add eax, [4]       ; inferred
    add [eax], 4       ; ambiguous
    add DWORD [eax], 4 ; explicit
A disassembler may output it when not necessary, however.
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Re:AT&T Syntax versus Intel Syntax by docandrew on Sunday November 13, 2022 @04:24PM (#33587491)
The comma is unnecessary too, so that’s 4 unneeded symbols.
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