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 <a name="Expressions"></a>
 <div class="header">
 <p>
 Next: <a href="Tagging-Insns.html#Tagging-Insns" accesskey="n" rel="next">Tagging Insns</a>, Previous: <a href="Defining-Attributes.html#Defining-Attributes" accesskey="p" rel="prev">Defining Attributes</a>, Up: <a href="Insn-Attributes.html#Insn-Attributes" accesskey="u" rel="up">Insn Attributes</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
 </div>
 <hr>
 <a name="Attribute-Expressions"></a>
 <h4 class="subsection">16.19.2 Attribute Expressions</h4>
 <a name="index-attribute-expressions"></a>

 <p>RTL expressions used to define attributes use the codes described above
 plus a few specific to attribute definitions, to be discussed below.
 Attribute value expressions must have one of the following forms:
 </p>
 <dl compact="compact">
 <dd><a name="index-const_005fint-and-attributes"></a>
 </dd>
 <dt><code>(const_int <var>i</var>)</code></dt>
 <dd><p>The integer <var>i</var> specifies the value of a numeric attribute.  <var>i</var>
 must be non-negative.
 </p>
 <p>The value of a numeric attribute can be specified either with a
 <code>const_int</code>, or as an integer represented as a string in
 <code>const_string</code>, <code>eq_attr</code> (see below), <code>attr</code>,
 <code>symbol_ref</code>, simple arithmetic expressions, and <code>set_attr</code>
 overrides on specific instructions (see <a href="Tagging-Insns.html#Tagging-Insns">Tagging Insns</a>).
 </p>
 <a name="index-const_005fstring-and-attributes"></a>
 </dd>
 <dt><code>(const_string <var>value</var>)</code></dt>
 <dd><p>The string <var>value</var> specifies a constant attribute value.
 If <var>value</var> is specified as &lsquo;<samp>&quot;*&quot;</samp>&rsquo;, it means that the default value of
 the attribute is to be used for the insn containing this expression.
 &lsquo;<samp>&quot;*&quot;</samp>&rsquo; obviously cannot be used in the <var>default</var> expression
 of a <code>define_attr</code>.
 </p>
 <p>If the attribute whose value is being specified is numeric, <var>value</var>
 must be a string containing a non-negative integer (normally
 <code>const_int</code> would be used in this case).  Otherwise, it must
 contain one of the valid values for the attribute.
 </p>
 <a name="index-if_005fthen_005felse-and-attributes"></a>
 </dd>
 <dt><code>(if_then_else <var>test</var> <var>true-value</var> <var>false-value</var>)</code></dt>
 <dd><p><var>test</var> specifies an attribute test, whose format is defined below.
 The value of this expression is <var>true-value</var> if <var>test</var> is true,
 otherwise it is <var>false-value</var>.
 </p>
 <a name="index-cond-and-attributes"></a>
 </dd>
 <dt><code>(cond [<var>test1</var> <var>value1</var> &hellip;] <var>default</var>)</code></dt>
 <dd><p>The first operand of this expression is a vector containing an even
 number of expressions and consisting of pairs of <var>test</var> and <var>value</var>
 expressions.  The value of the <code>cond</code> expression is that of the
 <var>value</var> corresponding to the first true <var>test</var> expression.  If
 none of the <var>test</var> expressions are true, the value of the <code>cond</code>
 expression is that of the <var>default</var> expression.
 </p></dd>
 </dl>

 <p><var>test</var> expressions can have one of the following forms:
 </p>
 <dl compact="compact">
 <dd><a name="index-const_005fint-and-attribute-tests"></a>
 </dd>
 <dt><code>(const_int <var>i</var>)</code></dt>
 <dd><p>This test is true if <var>i</var> is nonzero and false otherwise.
 </p>
 <a name="index-not-and-attributes"></a>
 <a name="index-ior-and-attributes"></a>
 <a name="index-and-and-attributes"></a>
 </dd>
 <dt><code>(not <var>test</var>)</code></dt>
 <dt><code>(ior <var>test1</var> <var>test2</var>)</code></dt>
 <dt><code>(and <var>test1</var> <var>test2</var>)</code></dt>
 <dd><p>These tests are true if the indicated logical function is true.
 </p>
 <a name="index-match_005foperand-and-attributes"></a>
 </dd>
 <dt><code>(match_operand:<var>m</var> <var>n</var> <var>pred</var> <var>constraints</var>)</code></dt>
 <dd><p>This test is true if operand <var>n</var> of the insn whose attribute value
 is being determined has mode <var>m</var> (this part of the test is ignored
 if <var>m</var> is <code>VOIDmode</code>) and the function specified by the string
 <var>pred</var> returns a nonzero value when passed operand <var>n</var> and mode
 <var>m</var> (this part of the test is ignored if <var>pred</var> is the null
 string).
 </p>
 <p>The <var>constraints</var> operand is ignored and should be the null string.
 </p>
 <a name="index-match_005ftest-and-attributes"></a>
 </dd>
 <dt><code>(match_test <var>c-expr</var>)</code></dt>
 <dd><p>The test is true if C expression <var>c-expr</var> is true.  In non-constant
 attributes, <var>c-expr</var> has access to the following variables:
 </p>
 <dl compact="compact">
 <dt><var>insn</var></dt>
 <dd><p>The rtl instruction under test.
 </p></dd>
 <dt><var>which_alternative</var></dt>
 <dd><p>The <code>define_insn</code> alternative that <var>insn</var> matches.
 See <a href="Output-Statement.html#Output-Statement">Output Statement</a>.
 </p></dd>
 <dt><var>operands</var></dt>
 <dd><p>An array of <var>insn</var>&rsquo;s rtl operands.
 </p></dd>
 </dl>

 <p><var>c-expr</var> behaves like the condition in a C <code>if</code> statement,
 so there is no need to explicitly convert the expression into a boolean
 0 or 1 value.  For example, the following two tests are equivalent:
 </p>
 <div class="smallexample">
 <pre class="smallexample">(match_test &quot;x &amp; 2&quot;)
 (match_test &quot;(x &amp; 2) != 0&quot;)
 </pre></div>

 <a name="index-le-and-attributes"></a>
 <a name="index-leu-and-attributes"></a>
 <a name="index-lt-and-attributes"></a>
 <a name="index-gt-and-attributes"></a>
 <a name="index-gtu-and-attributes"></a>
 <a name="index-ge-and-attributes"></a>
 <a name="index-geu-and-attributes"></a>
 <a name="index-ne-and-attributes"></a>
 <a name="index-eq-and-attributes"></a>
 <a name="index-plus-and-attributes"></a>
 <a name="index-minus-and-attributes"></a>
 <a name="index-mult-and-attributes"></a>
 <a name="index-div-and-attributes"></a>
 <a name="index-mod-and-attributes"></a>
 <a name="index-abs-and-attributes"></a>
 <a name="index-neg-and-attributes"></a>
 <a name="index-ashift-and-attributes"></a>
 <a name="index-lshiftrt-and-attributes"></a>
 <a name="index-ashiftrt-and-attributes"></a>
 </dd>
 <dt><code>(le <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(leu <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(lt <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(ltu <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(gt <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(gtu <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(ge <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(geu <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(ne <var>arith1</var> <var>arith2</var>)</code></dt>
 <dt><code>(eq <var>arith1</var> <var>arith2</var>)</code></dt>
 <dd><p>These tests are true if the indicated comparison of the two arithmetic
 expressions is true.  Arithmetic expressions are formed with
 <code>plus</code>, <code>minus</code>, <code>mult</code>, <code>div</code>, <code>mod</code>,
 <code>abs</code>, <code>neg</code>, <code>and</code>, <code>ior</code>, <code>xor</code>, <code>not</code>,
 <code>ashift</code>, <code>lshiftrt</code>, and <code>ashiftrt</code> expressions.
 </p>
 <a name="index-get_005fattr"></a>
 <p><code>const_int</code> and <code>symbol_ref</code> are always valid terms (see <a href="Insn-Lengths.html#Insn-Lengths">Insn Lengths</a>,for additional forms).  <code>symbol_ref</code> is a string
 denoting a C expression that yields an <code>int</code> when evaluated by the
 &lsquo;<samp>get_attr_&hellip;</samp>&rsquo; routine.  It should normally be a global
 variable.
 </p>
 <a name="index-eq_005fattr"></a>
 </dd>
 <dt><code>(eq_attr <var>name</var> <var>value</var>)</code></dt>
 <dd><p><var>name</var> is a string specifying the name of an attribute.
 </p>
 <p><var>value</var> is a string that is either a valid value for attribute
 <var>name</var>, a comma-separated list of values, or &lsquo;<samp>!</samp>&rsquo; followed by a
 value or list.  If <var>value</var> does not begin with a &lsquo;<samp>!</samp>&rsquo;, this
 test is true if the value of the <var>name</var> attribute of the current
 insn is in the list specified by <var>value</var>.  If <var>value</var> begins
 with a &lsquo;<samp>!</samp>&rsquo;, this test is true if the attribute&rsquo;s value is
 <em>not</em> in the specified list.
 </p>
 <p>For example,
 </p>
 <div class="smallexample">
 <pre class="smallexample">(eq_attr &quot;type&quot; &quot;load,store&quot;)
 </pre></div>

 <p>is equivalent to
 </p>
 <div class="smallexample">
 <pre class="smallexample">(ior (eq_attr &quot;type&quot; &quot;load&quot;) (eq_attr &quot;type&quot; &quot;store&quot;))
 </pre></div>

 <p>If <var>name</var> specifies an attribute of &lsquo;<samp>alternative</samp>&rsquo;, it refers to the
 value of the compiler variable <code>which_alternative</code>
 (see <a href="Output-Statement.html#Output-Statement">Output Statement</a>) and the values must be small integers.  For
 example,
 </p>
 <div class="smallexample">
 <pre class="smallexample">(eq_attr &quot;alternative&quot; &quot;2,3&quot;)
 </pre></div>

 <p>is equivalent to
 </p>
 <div class="smallexample">
 <pre class="smallexample">(ior (eq (symbol_ref &quot;which_alternative&quot;) (const_int 2))
      (eq (symbol_ref &quot;which_alternative&quot;) (const_int 3)))
 </pre></div>

 <p>Note that, for most attributes, an <code>eq_attr</code> test is simplified in cases
 where the value of the attribute being tested is known for all insns matching
 a particular pattern.  This is by far the most common case.
 </p>
 <a name="index-attr_005fflag"></a>
 </dd>
 <dt><code>(attr_flag <var>name</var>)</code></dt>
 <dd><p>The value of an <code>attr_flag</code> expression is true if the flag
 specified by <var>name</var> is true for the <code>insn</code> currently being
 scheduled.
 </p>
 <p><var>name</var> is a string specifying one of a fixed set of flags to test.
 Test the flags <code>forward</code> and <code>backward</code> to determine the
 direction of a conditional branch.
 </p>
 <p>This example describes a conditional branch delay slot which
 can be nullified for forward branches that are taken (annul-true) or
 for backward branches which are not taken (annul-false).
 </p>
 <div class="smallexample">
 <pre class="smallexample">(define_delay (eq_attr &quot;type&quot; &quot;cbranch&quot;)
   [(eq_attr &quot;in_branch_delay&quot; &quot;true&quot;)
    (and (eq_attr &quot;in_branch_delay&quot; &quot;true&quot;)
         (attr_flag &quot;forward&quot;))
    (and (eq_attr &quot;in_branch_delay&quot; &quot;true&quot;)
         (attr_flag &quot;backward&quot;))])
 </pre></div>

 <p>The <code>forward</code> and <code>backward</code> flags are false if the current
 <code>insn</code> being scheduled is not a conditional branch.
 </p>
 <p><code>attr_flag</code> is only used during delay slot scheduling and has no
 meaning to other passes of the compiler.
 </p>
 <a name="index-attr"></a>
 </dd>
 <dt><code>(attr <var>name</var>)</code></dt>
 <dd><p>The value of another attribute is returned.  This is most useful
 for numeric attributes, as <code>eq_attr</code> and <code>attr_flag</code>
 produce more efficient code for non-numeric attributes.
 </p></dd>
 </dl>

 <hr>
 <div class="header">
 <p>
 Next: <a href="Tagging-Insns.html#Tagging-Insns" accesskey="n" rel="next">Tagging Insns</a>, Previous: <a href="Defining-Attributes.html#Defining-Attributes" accesskey="p" rel="prev">Defining Attributes</a>, Up: <a href="Insn-Attributes.html#Insn-Attributes" accesskey="u" rel="up">Insn Attributes</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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	<a name="Expressions"></a>
	<div class="header">
	<p>
	Next: <a href="Tagging-Insns.html#Tagging-Insns" accesskey="n" rel="next">Tagging Insns</a>, Previous: <a href="Defining-Attributes.html#Defining-Attributes" accesskey="p" rel="prev">Defining Attributes</a>, Up: <a href="Insn-Attributes.html#Insn-Attributes" accesskey="u" rel="up">Insn Attributes</a>   [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
	</div>
	<hr>
	<a name="Attribute-Expressions"></a>
	<h4 class="subsection">16.19.2 Attribute Expressions</h4>
	<a name="index-attribute-expressions"></a>

	<p>RTL expressions used to define attributes use the codes described above
	plus a few specific to attribute definitions, to be discussed below.
	Attribute value expressions must have one of the following forms:
	</p>
	<dl compact="compact">
	<dd><a name="index-const_005fint-and-attributes"></a>
	</dd>
	<dt><code>(const_int <var>i</var>)</code></dt>
	<dd><p>The integer <var>i</var> specifies the value of a numeric attribute. <var>i</var>
	must be non-negative.
	</p>
	<p>The value of a numeric attribute can be specified either with a
	<code>const_int</code>, or as an integer represented as a string in
	<code>const_string</code>, <code>eq_attr</code> (see below), <code>attr</code>,
	<code>symbol_ref</code>, simple arithmetic expressions, and <code>set_attr</code>
	overrides on specific instructions (see <a href="Tagging-Insns.html#Tagging-Insns">Tagging Insns</a>).
	</p>
	<a name="index-const_005fstring-and-attributes"></a>
	</dd>
	<dt><code>(const_string <var>value</var>)</code></dt>
	<dd><p>The string <var>value</var> specifies a constant attribute value.
	If <var>value</var> is specified as ‘<samp>"*"</samp>’, it means that the default value of
	the attribute is to be used for the insn containing this expression.
	‘<samp>"*"</samp>’ obviously cannot be used in the <var>default</var> expression
	of a <code>define_attr</code>.
	</p>
	<p>If the attribute whose value is being specified is numeric, <var>value</var>
	must be a string containing a non-negative integer (normally
	<code>const_int</code> would be used in this case). Otherwise, it must
	contain one of the valid values for the attribute.
	</p>
	<a name="index-if_005fthen_005felse-and-attributes"></a>
	</dd>
	<dt><code>(if_then_else <var>test</var> <var>true-value</var> <var>false-value</var>)</code></dt>
	<dd><p><var>test</var> specifies an attribute test, whose format is defined below.
	The value of this expression is <var>true-value</var> if <var>test</var> is true,
	otherwise it is <var>false-value</var>.
	</p>
	<a name="index-cond-and-attributes"></a>
	</dd>
	<dt><code>(cond [<var>test1</var> <var>value1</var> …] <var>default</var>)</code></dt>
	<dd><p>The first operand of this expression is a vector containing an even
	number of expressions and consisting of pairs of <var>test</var> and <var>value</var>
	expressions. The value of the <code>cond</code> expression is that of the
	<var>value</var> corresponding to the first true <var>test</var> expression. If
	none of the <var>test</var> expressions are true, the value of the <code>cond</code>
	expression is that of the <var>default</var> expression.
	</p></dd>
	</dl>

	<p><var>test</var> expressions can have one of the following forms:
	</p>
	<dl compact="compact">
	<dd><a name="index-const_005fint-and-attribute-tests"></a>
	</dd>
	<dt><code>(const_int <var>i</var>)</code></dt>
	<dd><p>This test is true if <var>i</var> is nonzero and false otherwise.
	</p>
	<a name="index-not-and-attributes"></a>
	<a name="index-ior-and-attributes"></a>
	<a name="index-and-and-attributes"></a>
	</dd>
	<dt><code>(not <var>test</var>)</code></dt>
	<dt><code>(ior <var>test1</var> <var>test2</var>)</code></dt>
	<dt><code>(and <var>test1</var> <var>test2</var>)</code></dt>
	<dd><p>These tests are true if the indicated logical function is true.
	</p>
	<a name="index-match_005foperand-and-attributes"></a>
	</dd>
	<dt><code>(match_operand:<var>m</var> <var>n</var> <var>pred</var> <var>constraints</var>)</code></dt>
	<dd><p>This test is true if operand <var>n</var> of the insn whose attribute value
	is being determined has mode <var>m</var> (this part of the test is ignored
	if <var>m</var> is <code>VOIDmode</code>) and the function specified by the string
	<var>pred</var> returns a nonzero value when passed operand <var>n</var> and mode
	<var>m</var> (this part of the test is ignored if <var>pred</var> is the null
	string).
	</p>
	<p>The <var>constraints</var> operand is ignored and should be the null string.
	</p>
	<a name="index-match_005ftest-and-attributes"></a>
	</dd>
	<dt><code>(match_test <var>c-expr</var>)</code></dt>
	<dd><p>The test is true if C expression <var>c-expr</var> is true. In non-constant
	attributes, <var>c-expr</var> has access to the following variables:
	</p>
	<dl compact="compact">
	<dt><var>insn</var></dt>
	<dd><p>The rtl instruction under test.
	</p></dd>
	<dt><var>which_alternative</var></dt>
	<dd><p>The <code>define_insn</code> alternative that <var>insn</var> matches.
	See <a href="Output-Statement.html#Output-Statement">Output Statement</a>.
	</p></dd>
	<dt><var>operands</var></dt>
	<dd><p>An array of <var>insn</var>’s rtl operands.
	</p></dd>
	</dl>

	<p><var>c-expr</var> behaves like the condition in a C <code>if</code> statement,
	so there is no need to explicitly convert the expression into a boolean
	0 or 1 value. For example, the following two tests are equivalent:
	</p>
	<div class="smallexample">
	<pre class="smallexample">(match_test "x & 2")
	(match_test "(x & 2) != 0")
	</pre></div>

	<a name="index-le-and-attributes"></a>
	<a name="index-leu-and-attributes"></a>
	<a name="index-lt-and-attributes"></a>
	<a name="index-gt-and-attributes"></a>
	<a name="index-gtu-and-attributes"></a>
	<a name="index-ge-and-attributes"></a>
	<a name="index-geu-and-attributes"></a>
	<a name="index-ne-and-attributes"></a>
	<a name="index-eq-and-attributes"></a>
	<a name="index-plus-and-attributes"></a>
	<a name="index-minus-and-attributes"></a>
	<a name="index-mult-and-attributes"></a>
	<a name="index-div-and-attributes"></a>
	<a name="index-mod-and-attributes"></a>
	<a name="index-abs-and-attributes"></a>
	<a name="index-neg-and-attributes"></a>
	<a name="index-ashift-and-attributes"></a>
	<a name="index-lshiftrt-and-attributes"></a>
	<a name="index-ashiftrt-and-attributes"></a>
	</dd>
	<dt><code>(le <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(leu <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(lt <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(ltu <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(gt <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(gtu <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(ge <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(geu <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(ne <var>arith1</var> <var>arith2</var>)</code></dt>
	<dt><code>(eq <var>arith1</var> <var>arith2</var>)</code></dt>
	<dd><p>These tests are true if the indicated comparison of the two arithmetic
	expressions is true. Arithmetic expressions are formed with
	<code>plus</code>, <code>minus</code>, <code>mult</code>, <code>div</code>, <code>mod</code>,
	<code>abs</code>, <code>neg</code>, <code>and</code>, <code>ior</code>, <code>xor</code>, <code>not</code>,
	<code>ashift</code>, <code>lshiftrt</code>, and <code>ashiftrt</code> expressions.
	</p>
	<a name="index-get_005fattr"></a>
	<p><code>const_int</code> and <code>symbol_ref</code> are always valid terms (see <a href="Insn-Lengths.html#Insn-Lengths">Insn Lengths</a>,for additional forms). <code>symbol_ref</code> is a string
	denoting a C expression that yields an <code>int</code> when evaluated by the
	‘<samp>get_attr_…</samp>’ routine. It should normally be a global
	variable.
	</p>
	<a name="index-eq_005fattr"></a>
	</dd>
	<dt><code>(eq_attr <var>name</var> <var>value</var>)</code></dt>
	<dd><p><var>name</var> is a string specifying the name of an attribute.
	</p>
	<p><var>value</var> is a string that is either a valid value for attribute
	<var>name</var>, a comma-separated list of values, or ‘<samp>!</samp>’ followed by a
	value or list. If <var>value</var> does not begin with a ‘<samp>!</samp>’, this
	test is true if the value of the <var>name</var> attribute of the current
	insn is in the list specified by <var>value</var>. If <var>value</var> begins
	with a ‘<samp>!</samp>’, this test is true if the attribute’s value is
	<em>not</em> in the specified list.
	</p>
	<p>For example,
	</p>
	<div class="smallexample">
	<pre class="smallexample">(eq_attr "type" "load,store")
	</pre></div>

	<p>is equivalent to
	</p>
	<div class="smallexample">
	<pre class="smallexample">(ior (eq_attr "type" "load") (eq_attr "type" "store"))
	</pre></div>

	<p>If <var>name</var> specifies an attribute of ‘<samp>alternative</samp>’, it refers to the
	value of the compiler variable <code>which_alternative</code>
	(see <a href="Output-Statement.html#Output-Statement">Output Statement</a>) and the values must be small integers. For
	example,
	</p>
	<div class="smallexample">
	<pre class="smallexample">(eq_attr "alternative" "2,3")
	</pre></div>

	<p>is equivalent to
	</p>
	<div class="smallexample">
	<pre class="smallexample">(ior (eq (symbol_ref "which_alternative") (const_int 2))
	(eq (symbol_ref "which_alternative") (const_int 3)))
	</pre></div>

	<p>Note that, for most attributes, an <code>eq_attr</code> test is simplified in cases
	where the value of the attribute being tested is known for all insns matching
	a particular pattern. This is by far the most common case.
	</p>
	<a name="index-attr_005fflag"></a>
	</dd>
	<dt><code>(attr_flag <var>name</var>)</code></dt>
	<dd><p>The value of an <code>attr_flag</code> expression is true if the flag
	specified by <var>name</var> is true for the <code>insn</code> currently being
	scheduled.
	</p>
	<p><var>name</var> is a string specifying one of a fixed set of flags to test.
	Test the flags <code>forward</code> and <code>backward</code> to determine the
	direction of a conditional branch.
	</p>
	<p>This example describes a conditional branch delay slot which
	can be nullified for forward branches that are taken (annul-true) or
	for backward branches which are not taken (annul-false).
	</p>
	<div class="smallexample">
	<pre class="smallexample">(define_delay (eq_attr "type" "cbranch")
	[(eq_attr "in_branch_delay" "true")
	(and (eq_attr "in_branch_delay" "true")
	(attr_flag "forward"))
	(and (eq_attr "in_branch_delay" "true")
	(attr_flag "backward"))])
	</pre></div>

	<p>The <code>forward</code> and <code>backward</code> flags are false if the current
	<code>insn</code> being scheduled is not a conditional branch.
	</p>
	<p><code>attr_flag</code> is only used during delay slot scheduling and has no
	meaning to other passes of the compiler.
	</p>
	<a name="index-attr"></a>
	</dd>
	<dt><code>(attr <var>name</var>)</code></dt>
	<dd><p>The value of another attribute is returned. This is most useful
	for numeric attributes, as <code>eq_attr</code> and <code>attr_flag</code>
	produce more efficient code for non-numeric attributes.
	</p></dd>
	</dl>

	<hr>
	<div class="header">
	<p>
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