#### 9.3.2.1 Special Characters

`%`

  A register name can optionally be prefixed by a ‘`%`’ character. So register `%r0` is equivalent to `r0` in the assembly code.

`#`

  The presence of a ‘`#`’ character within a line (but not at the start of a line) indicates the start of a comment that extends to the end of the current line.

  Note: if a line starts with a ‘`#`’ character then it can also be a logical line number directive (see Comments) or a preprocessor control command (see Preprocessing).

`@`

  Prefixing an operand with an ‘`@`’ specifies that the operand is a symbol and not a register. This is how the assembler disambiguates the use of an ARC register name as a symbol. So the instruction

      mov r0, @r0

  moves the address of symbol `r0` into register `r0`.

```

  The ‘```’ (backtick) character is used to separate statements on a single line.

`-`

  Used as a separator to obtain a sequence of commands from a C preprocessor macro.