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Comment by masklinn | Hacker News Reader

> 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

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]

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.

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.

The comma is unnecessary too, so that’s 4 unneeded symbols.