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<title>Using as: Statements</title>
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<a name="Statements"></a>
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<div class="header">
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<p>
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Next: <a href="Constants.html#Constants" accesskey="n" rel="next">Constants</a>, Previous: <a href="Symbol-Intro.html#Symbol-Intro" accesskey="p" rel="prev">Symbol Intro</a>, Up: <a href="Syntax.html#Syntax" accesskey="u" rel="up">Syntax</a> [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="AS-Index.html#AS-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
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<a name="Statements-1"></a>
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<h3 class="section">3.5 Statements</h3>
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<a name="index-statements_002c-structure-of"></a>
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<a name="index-line-separator-character"></a>
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<a name="index-statement-separator-character"></a>
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<p>A <em>statement</em> ends at a newline character (‘<samp>\n</samp>’) or a
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<em>line separator character</em>. The line separator character is target
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specific and described in the <em>Syntax</em> section of each
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target’s documentation. Not all targets support a line separator character.
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The newline or line separator character is considered to be part of the
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preceding statement. Newlines and separators within character constants are an
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exception: they do not end statements.
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</p>
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<a name="index-newline_002c-required-at-file-end"></a>
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<a name="index-EOF_002c-newline-must-precede"></a>
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<p>It is an error to end any statement with end-of-file: the last
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character of any input file should be a newline.
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</p>
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<p>An empty statement is allowed, and may include whitespace. It is ignored.
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</p>
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<a name="index-instructions-and-directives"></a>
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<a name="index-directives-and-instructions"></a>
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<p>A statement begins with zero or more labels, optionally followed by a
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key symbol which determines what kind of statement it is. The key
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symbol determines the syntax of the rest of the statement. If the
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symbol begins with a dot ‘<samp>.</samp>’ then the statement is an assembler
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directive: typically valid for any computer. If the symbol begins with
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a letter the statement is an assembly language <em>instruction</em>: it
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assembles into a machine language instruction.
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Different versions of <code>as</code> for different computers
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recognize different instructions. In fact, the same symbol may
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represent a different instruction in a different computer’s assembly
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language.
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</p>
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<a name="index-_003a-_0028label_0029"></a>
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<a name="index-label-_0028_003a_0029"></a>
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<p>A label is a symbol immediately followed by a colon (<code>:</code>).
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Whitespace before a label or after a colon is permitted, but you may not
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have whitespace between a label’s symbol and its colon. See <a href="Labels.html#Labels">Labels</a>.
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</p>
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<p>For HPPA targets, labels need not be immediately followed by a colon, but
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the definition of a label must begin in column zero. This also implies that
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only one label may be defined on each line.
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</p>
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<div class="smallexample">
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<pre class="smallexample">label: .directive followed by something
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another_label: # This is an empty statement.
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instruction operand_1, operand_2, …
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</pre></div>
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<p>
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