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Next: <a href="GIMPLE_005fEH_005fFILTER.html#GIMPLE_005fEH_005fFILTER" accesskey="n" rel="next"><code>GIMPLE_EH_FILTER</code></a>, Previous: <a href="GIMPLE_005fCOND.html#GIMPLE_005fCOND" accesskey="p" rel="prev"><code>GIMPLE_COND</code></a>, Up: <a href="Tuple-specific-accessors.html#Tuple-specific-accessors" accesskey="u" rel="up">Tuple specific accessors</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="GIMPLE_005fDEBUG-1"></a>
<h4 class="subsection">11.8.7 <code>GIMPLE_DEBUG</code></h4>
<a name="index-GIMPLE_005fDEBUG"></a>
<a name="index-GIMPLE_005fDEBUG_005fBIND"></a>

<dl>
<dt><a name="index-_002agimple_005fbuild_005fdebug_005fbind"></a>GIMPLE function: <em>gdebug</em> <strong>*gimple_build_debug_bind</strong> <em>(tree var, tree value, gimple stmt)</em></dt>
<dd><p>Build a <code>GIMPLE_DEBUG</code> statement with <code>GIMPLE_DEBUG_BIND</code> of
<code>subcode</code>.  The effect of this statement is to tell debug
information generation machinery that the value of user variable
<code>var</code> is given by <code>value</code> at that point, and to remain with
that value until <code>var</code> runs out of scope, a
dynamically-subsequent debug bind statement overrides the binding, or
conflicting values reach a control flow merge point.  Even if
components of the <code>value</code> expression change afterwards, the
variable is supposed to retain the same value, though not necessarily
the same location.
</p>
<p>It is expected that <code>var</code> be most often a tree for automatic user
variables (<code>VAR_DECL</code> or <code>PARM_DECL</code>) that satisfy the
requirements for gimple registers, but it may also be a tree for a
scalarized component of a user variable (<code>ARRAY_REF</code>,
<code>COMPONENT_REF</code>), or a debug temporary (<code>DEBUG_EXPR_DECL</code>).
</p>
<p>As for <code>value</code>, it can be an arbitrary tree expression, but it is
recommended that it be in a suitable form for a gimple assignment
<code>RHS</code>.  It is not expected that user variables that could appear
as <code>var</code> ever appear in <code>value</code>, because in the latter we&rsquo;d
have their <code>SSA_NAME</code>s instead, but even if they were not in SSA
form, user variables appearing in <code>value</code> are to be regarded as
part of the executable code space, whereas those in <code>var</code> are to
be regarded as part of the source code space.  There is no way to
refer to the value bound to a user variable within a <code>value</code>
expression.
</p>
<p>If <code>value</code> is <code>GIMPLE_DEBUG_BIND_NOVALUE</code>, debug information
generation machinery is informed that the variable <code>var</code> is
unbound, i.e., that its value is indeterminate, which sometimes means
it is really unavailable, and other times that the compiler could not
keep track of it.
</p>
<p>Block and location information for the newly-created stmt are
taken from <code>stmt</code>, if given.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005fget_005fvar"></a>GIMPLE function: <em>tree</em> <strong>gimple_debug_bind_get_var</strong> <em>(gimple stmt)</em></dt>
<dd><p>Return the user variable <var>var</var> that is bound at <code>stmt</code>.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005fget_005fvalue"></a>GIMPLE function: <em>tree</em> <strong>gimple_debug_bind_get_value</strong> <em>(gimple stmt)</em></dt>
<dd><p>Return the value expression that is bound to a user variable at
<code>stmt</code>.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005fget_005fvalue_005fptr"></a>GIMPLE function: <em>tree *</em> <strong>gimple_debug_bind_get_value_ptr</strong> <em>(gimple stmt)</em></dt>
<dd><p>Return a pointer to the value expression that is bound to a user
variable at <code>stmt</code>.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005fset_005fvar"></a>GIMPLE function: <em>void</em> <strong>gimple_debug_bind_set_var</strong> <em>(gimple stmt, tree var)</em></dt>
<dd><p>Modify the user variable bound at <code>stmt</code> to <var>var</var>.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005fset_005fvalue"></a>GIMPLE function: <em>void</em> <strong>gimple_debug_bind_set_value</strong> <em>(gimple stmt, tree var)</em></dt>
<dd><p>Modify the value bound to the user variable bound at <code>stmt</code> to
<var>value</var>.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005freset_005fvalue"></a>GIMPLE function: <em>void</em> <strong>gimple_debug_bind_reset_value</strong> <em>(gimple stmt)</em></dt>
<dd><p>Modify the value bound to the user variable bound at <code>stmt</code> so
that the variable becomes unbound.
</p></dd></dl>

<dl>
<dt><a name="index-gimple_005fdebug_005fbind_005fhas_005fvalue_005fp"></a>GIMPLE function: <em>bool</em> <strong>gimple_debug_bind_has_value_p</strong> <em>(gimple stmt)</em></dt>
<dd><p>Return <code>TRUE</code> if <code>stmt</code> binds a user variable to a value,
and <code>FALSE</code> if it unbinds the variable.
</p></dd></dl>

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Next: <a href="GIMPLE_005fEH_005fFILTER.html#GIMPLE_005fEH_005fFILTER" accesskey="n" rel="next"><code>GIMPLE_EH_FILTER</code></a>, Previous: <a href="GIMPLE_005fCOND.html#GIMPLE_005fCOND" accesskey="p" rel="prev"><code>GIMPLE_COND</code></a>, Up: <a href="Tuple-specific-accessors.html#Tuple-specific-accessors" accesskey="u" rel="up">Tuple specific accessors</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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