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<div class="section" id="gimple-statements">
<h1>Gimple statements<a class="headerlink" href="#gimple-statements" title="Permalink to this headline">¶</a></h1>
<dl class="class">
<dt id="gcc.Gimple">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">Gimple</tt><a class="headerlink" href="#gcc.Gimple" title="Permalink to this definition">¶</a></dt>
<dd><p>A statement, in GCC’s Gimple representation.</p>
<p>The __str__ method is implemented using GCC’s own pretty-printer for gimple,
so e.g.:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="nb">str</span><span class="p">(</span><span class="n">stmt</span><span class="p">)</span>
</pre></div>
</div>
<p>might return:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="s">'D.3259 = (long unsigned int) i;'</span>
</pre></div>
</div>
<dl class="attribute">
<dt id="gcc.Gimple.loc">
<tt class="descname">loc</tt><a class="headerlink" href="#gcc.Gimple.loc" title="Permalink to this definition">¶</a></dt>
<dd><p>Source code location of this statement, as a <a class="reference internal" href="basics.html#gcc.Location" title="gcc.Location"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Location</span></tt></a> (or None)</p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.Gimple.block">
<tt class="descname">block</tt><a class="headerlink" href="#gcc.Gimple.block" title="Permalink to this definition">¶</a></dt>
<dd><p>The lexical block holding this statement, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.Gimple.exprtype">
<tt class="descname">exprtype</tt><a class="headerlink" href="#gcc.Gimple.exprtype" title="Permalink to this definition">¶</a></dt>
<dd><p>The type of the main expression computed by this statement, as a
<a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a> (which might be <tt class="xref py py-class docutils literal"><span class="pre">gcc.VoidType</span></tt>)</p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.Gimple.str_no_uid">
<tt class="descname">str_no_uid</tt><a class="headerlink" href="#gcc.Gimple.str_no_uid" title="Permalink to this definition">¶</a></dt>
<dd><p>A string representation of this statement, like str(), but without
including any internal UIDs.</p>
<p>This is intended for use in selftests that compare output against some
expected value, to avoid embedding values that change into the expected
output.</p>
<p>For example, given an assignment to a
temporary, the <cite>str(stmt)</cite> for the gcc.GimpleAssign might be:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="s">'D.3259 = (long unsigned int) i;'</span>
</pre></div>
</div>
<p>where the UID “3259” is liable to change from compile to compile, whereas
the <cite>stmt.str_no_uid</cite> has value:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="s">'D.xxxx = (long unsigned int) i;'</span>
</pre></div>
</div>
<p>which won’t arbitrarily change each time.</p>
</dd></dl>
<dl class="method">
<dt id="gcc.Gimple.walk_tree">
<tt class="descname">walk_tree</tt><big>(</big><em>callback</em>, <em>*args</em>, <em>**kwargs</em><big>)</big><a class="headerlink" href="#gcc.Gimple.walk_tree" title="Permalink to this definition">¶</a></dt>
<dd><p>Visit all <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a> nodes associated with this
statement, potentially more than once each. This will visit both the
left-hand-side and right-hand-side operands of the statement (if any),
and recursively visit any of their child nodes.</p>
<p>For each node, the callback is invoked, supplying the node, and any
extra positional and keyword arguments passed to <cite>walk_tree</cite>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">callback</span><span class="p">(</span><span class="n">node</span><span class="p">,</span> <span class="o">*</span><span class="n">args</span><span class="p">,</span> <span class="o">**</span><span class="n">kwargs</span><span class="p">)</span>
</pre></div>
</div>
<p>If the callback returns a true value, the traversal stops, and that
<a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a> is the result of the call to <cite>walk_tree</cite>.
Otherwise, the traversal continues, and <cite>walk_tree</cite> eventually returns
<cite>None</cite>.</p>
</dd></dl>
</dd></dl>
<p><a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a> has various subclasses, each corresponding to the
one of the kinds of statement within GCC’s internal representation.</p>
<p>The following subclasses have been wrapped for use from Python scripts:</p>
<table border="1" class="docutils">
<colgroup>
<col width="38%" />
<col width="62%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Subclass</th>
<th class="head">Meaning</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><a class="reference internal" href="#gcc.GimpleAssign" title="gcc.GimpleAssign"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleAssign</span></tt></a></td>
<td><p class="first">An assignment of an expression to
an l-value:</p>
<div class="last highlight-python"><pre>LHS = RHS1 EXPRCODE RHS2;</pre>
</div>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="#gcc.GimpleCall" title="gcc.GimpleCall"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleCall</span></tt></a></td>
<td><p class="first">A function call:</p>
<div class="last highlight-python"><pre>[ LHS = ] FN(ARG1, ..., ARGN);</pre>
</div>
</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="#gcc.GimpleCond" title="gcc.GimpleCond"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleCond</span></tt></a></td>
<td><p class="first">A conditional jump, of the form:</p>
<div class="last highlight-python"><pre>if (LHS EXPRCODE RHS) goto TRUE_LABEL else goto FALSE_LABEL;</pre>
</div>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="#gcc.GimpleLabel" title="gcc.GimpleLabel"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleLabel</span></tt></a></td>
<td><p class="first">A label statement (jump target):</p>
<div class="last highlight-python"><pre>LABEL:</pre>
</div>
</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="#gcc.GimplePhi" title="gcc.GimplePhi"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimplePhi</span></tt></a></td>
<td><p class="first">Used in the SSA passes:</p>
<div class="last highlight-python"><pre>LHS = PHI <ARG1, ..., ARGN>;</pre>
</div>
</td>
</tr>
<tr class="row-odd"><td><a class="reference internal" href="#gcc.GimpleReturn" title="gcc.GimpleReturn"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleReturn</span></tt></a></td>
<td><p class="first">A “return” statement:</p>
<div class="last highlight-python"><div class="highlight"><pre><span class="n">RETURN</span> <span class="p">[</span><span class="n">RETVAL</span><span class="p">];</span>
</pre></div>
</div>
</td>
</tr>
<tr class="row-even"><td><a class="reference internal" href="#gcc.GimpleSwitch" title="gcc.GimpleSwitch"><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleSwitch</span></tt></a></td>
<td><p class="first">A switch statement:</p>
<div class="last highlight-python"><pre>switch (INDEXVAR)
{
case LAB1: ...; break;
...
case LABN: ...; break;
default: ...
}</pre>
</div>
</td>
</tr>
</tbody>
</table>
<p>There are some additional subclasses that have not yet been fully wrapped by
the Python plugin (email the <a class="reference external" href="https://fedorahosted.org/mailman/listinfo/gcc-python-plugin/">gcc-python-plugin’s mailing list</a> if you’re
interested in working with these):</p>
<table border="1" class="docutils">
<colgroup>
<col width="43%" />
<col width="57%" />
</colgroup>
<thead valign="bottom">
<tr class="row-odd"><th class="head">Subclass</th>
<th class="head">Meaning</th>
</tr>
</thead>
<tbody valign="top">
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleAsm</span></tt></td>
<td>One or more inline assembly
statements</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleBind</span></tt></td>
<td>A lexical scope</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleCatch</span></tt></td>
<td>An exception handler</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleDebug</span></tt></td>
<td>A debug statement</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleEhDispatch</span></tt></td>
<td>Used in exception-handling</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleEhFilter</span></tt></td>
<td>Used in exception-handling</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleEhMustNotThrow</span></tt></td>
<td>Used in exception-handling</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleErrorMark</span></tt></td>
<td>A dummy statement used for handling internal errors</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleGoto</span></tt></td>
<td>An unconditional jump</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleNop</span></tt></td>
<td>The “do nothing” statement</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpAtomicLoad</span></tt></td>
<td>Used for implementing OpenMP</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpAtomicStore</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpContinue</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpCritical</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpFor</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpMaster</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpOrdered</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpParallel</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpReturn</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpSection</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpSections</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpSectionsSwitch</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpSingle</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleOmpTask</span></tt></td>
<td>(ditto)</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimplePredict</span></tt></td>
<td>A hint for branch prediction</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleResx</span></tt></td>
<td>Resumes execution after an exception</td>
</tr>
<tr class="row-even"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleTry</span></tt></td>
<td>A try/catch or try/finally statement</td>
</tr>
<tr class="row-odd"><td><tt class="xref py py-class docutils literal"><span class="pre">gcc.GimpleWithCleanupExpr</span></tt></td>
<td>Internally used when generating GIMPLE</td>
</tr>
</tbody>
</table>
<dl class="class">
<dt id="gcc.GimpleAssign">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimpleAssign</tt><a class="headerlink" href="#gcc.GimpleAssign" title="Permalink to this definition">¶</a></dt>
<dd><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a>: an assignment of an expression to an
l-value:</p>
<div class="highlight-python"><pre>LHS = RHS1 EXPRCODE RHS2;</pre>
</div>
<dl class="attribute">
<dt id="gcc.GimpleAssign.lhs">
<tt class="descname">lhs</tt><a class="headerlink" href="#gcc.GimpleAssign.lhs" title="Permalink to this definition">¶</a></dt>
<dd><p>Left-hand-side of the assignment, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleAssign.rhs">
<tt class="descname">rhs</tt><a class="headerlink" href="#gcc.GimpleAssign.rhs" title="Permalink to this definition">¶</a></dt>
<dd><p>The operands on the right-hand-side of the expression, as a list of
<a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a> instances (either of length 1 or length 2,
depending on the expression).</p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleAssign.exprcode">
<tt class="descname">exprcode</tt><a class="headerlink" href="#gcc.GimpleAssign.exprcode" title="Permalink to this definition">¶</a></dt>
<dd><p>The kind of the expression, as an <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a> subclass (the type
itself, not an instance)</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="gcc.GimpleCall">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimpleCall</tt><a class="headerlink" href="#gcc.GimpleCall" title="Permalink to this definition">¶</a></dt>
<dd><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a>: an invocation of a function, potentially
assigning the result to an l-value:</p>
<div class="highlight-python"><pre>[ LHS = ] FN(ARG1, ..., ARGN);</pre>
</div>
<dl class="attribute">
<dt id="gcc.GimpleCall.lhs">
<tt class="descname">lhs</tt><a class="headerlink" href="#gcc.GimpleCall.lhs" title="Permalink to this definition">¶</a></dt>
<dd><p>Left-hand-side of the assignment, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a>, or <cite>None</cite></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCall.rhs">
<tt class="descname">rhs</tt><a class="headerlink" href="#gcc.GimpleCall.rhs" title="Permalink to this definition">¶</a></dt>
<dd><p>The operands on the right-hand-side of the expression, as a list of
<a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a> instances</p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCall.fn">
<tt class="descname">fn</tt><a class="headerlink" href="#gcc.GimpleCall.fn" title="Permalink to this definition">¶</a></dt>
<dd><p>The function being called, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCall.fndecl">
<tt class="descname">fndecl</tt><a class="headerlink" href="#gcc.GimpleCall.fndecl" title="Permalink to this definition">¶</a></dt>
<dd><p>The declaration of the function being called (if any), as a
<a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCall.args">
<tt class="descname">args</tt><a class="headerlink" href="#gcc.GimpleCall.args" title="Permalink to this definition">¶</a></dt>
<dd><p>The arguments for the call, as a list of <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCall.noreturn">
<tt class="descname">noreturn</tt><a class="headerlink" href="#gcc.GimpleCall.noreturn" title="Permalink to this definition">¶</a></dt>
<dd><p>(boolean) Has this call been marked as not returning? (e.g. a call to
<cite>exit</cite>)</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="gcc.GimpleReturn">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimpleReturn</tt><a class="headerlink" href="#gcc.GimpleReturn" title="Permalink to this definition">¶</a></dt>
<dd><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a>: a “return” statement, signifying the end
of a <a class="reference internal" href="cfg.html#gcc.BasicBlock" title="gcc.BasicBlock"><tt class="xref py py-class docutils literal"><span class="pre">gcc.BasicBlock</span></tt></a>:</p>
<div class="highlight-python"><div class="highlight"><pre><span class="n">RETURN</span> <span class="p">[</span><span class="n">RETVAL</span><span class="p">];</span>
</pre></div>
</div>
<dl class="attribute">
<dt id="gcc.GimpleReturn.retval">
<tt class="descname">retval</tt><a class="headerlink" href="#gcc.GimpleReturn.retval" title="Permalink to this definition">¶</a></dt>
<dd></dd></dl>
<p>The return value, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a>, or <cite>None</cite>.</p>
</dd></dl>
<dl class="class">
<dt id="gcc.GimpleCond">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimpleCond</tt><a class="headerlink" href="#gcc.GimpleCond" title="Permalink to this definition">¶</a></dt>
<dd><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a>: a conditional jump, of the form:</p>
<div class="highlight-python"><pre>if (LHS EXPRCODE RHS) goto TRUE_LABEL else goto FALSE_LABEL</pre>
</div>
<dl class="attribute">
<dt id="gcc.GimpleCond.lhs">
<tt class="descname">lhs</tt><a class="headerlink" href="#gcc.GimpleCond.lhs" title="Permalink to this definition">¶</a></dt>
<dd><p>Left-hand-side of the comparison, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCond.exprcode">
<tt class="descname">exprcode</tt><a class="headerlink" href="#gcc.GimpleCond.exprcode" title="Permalink to this definition">¶</a></dt>
<dd><p>The comparison predicate, as a <a class="reference internal" href="tree.html#gcc.Comparison" title="gcc.Comparison"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Comparison</span></tt></a> subclass (the
type itself, not an instance). For example, the gcc.GimpleCond statement
for this fragment of C code:</p>
<div class="highlight-python"><pre>if (a == b)</pre>
</div>
<p>would have stmt.exprcode == gcc.EqExpr</p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCond.rhs">
<tt class="descname">rhs</tt><a class="headerlink" href="#gcc.GimpleCond.rhs" title="Permalink to this definition">¶</a></dt>
<dd><p>The right-hand-side of the comparison, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCond.true_label">
<tt class="descname">true_label</tt><a class="headerlink" href="#gcc.GimpleCond.true_label" title="Permalink to this definition">¶</a></dt>
<dd><p>The <tt class="xref py py-class docutils literal"><span class="pre">gcc.LabelDecl</span></tt> node used as the jump target for when the
comparison is true</p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleCond.false_label">
<tt class="descname">false_label</tt><a class="headerlink" href="#gcc.GimpleCond.false_label" title="Permalink to this definition">¶</a></dt>
<dd><p>The <tt class="xref py py-class docutils literal"><span class="pre">gcc.LabelDecl</span></tt> node used as the jump target for when the
comparison is false</p>
</dd></dl>
<p>Note that a C conditional of the form:</p>
<div class="highlight-python"><pre>if (some_int) {suiteA} else {suiteB}</pre>
</div>
<p>is implicitly expanded to:</p>
<div class="highlight-python"><pre>if (some_int != 0) {suiteA} else {suiteB}</pre>
</div>
<p>and this becomes a gcc.GimpleCond with <cite>lhs</cite> as the integer, <cite>exprcode</cite> as
<cite><type ‘gcc.NeExpr’></cite>, and <cite>rhs</cite> as <cite>gcc.IntegerCst(0)</cite>.</p>
</dd></dl>
<dl class="class">
<dt id="gcc.GimplePhi">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimplePhi</tt><a class="headerlink" href="#gcc.GimplePhi" title="Permalink to this definition">¶</a></dt>
<dd><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a> used in the SSA passes: a “PHI” or
“phoney” function, for merging the various possible values a variable can
have based on the edge that we entered this <a class="reference internal" href="cfg.html#gcc.BasicBlock" title="gcc.BasicBlock"><tt class="xref py py-class docutils literal"><span class="pre">gcc.BasicBlock</span></tt></a> on:</p>
<div class="highlight-python"><pre>LHS = PHI <ARG1, ..., ARGN>;</pre>
</div>
<dl class="attribute">
<dt id="gcc.GimplePhi.lhs">
<tt class="descname">lhs</tt><a class="headerlink" href="#gcc.GimplePhi.lhs" title="Permalink to this definition">¶</a></dt>
<dd><p>Left-hand-side of the assignment, as a <tt class="xref py py-class docutils literal"><span class="pre">gcc.SsaName</span></tt></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimplePhi.args">
<tt class="descname">args</tt><a class="headerlink" href="#gcc.GimplePhi.args" title="Permalink to this definition">¶</a></dt>
<dd><p>A list of (<a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a>, <a class="reference internal" href="cfg.html#gcc.Edge" title="gcc.Edge"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Edge</span></tt></a>) pairs representing
the possible (expr, edge) inputs. Each <cite>expr</cite> is either a
<tt class="xref py py-class docutils literal"><span class="pre">gcc.SsaName</span></tt> or a <a class="reference internal" href="tree.html#gcc.Constant" title="gcc.Constant"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Constant</span></tt></a></p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="gcc.GimpleSwitch">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimpleSwitch</tt><a class="headerlink" href="#gcc.GimpleSwitch" title="Permalink to this definition">¶</a></dt>
<dd><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a>: a switch statement, signifying the end of a
<a class="reference internal" href="cfg.html#gcc.BasicBlock" title="gcc.BasicBlock"><tt class="xref py py-class docutils literal"><span class="pre">gcc.BasicBlock</span></tt></a>:</p>
<div class="highlight-python"><pre>switch (INDEXVAR)
{
case LAB1: ...; break;
...
case LABN: ...; break;
default: ...
}</pre>
</div>
<dl class="attribute">
<dt id="gcc.GimpleSwitch.indexvar">
<tt class="descname">indexvar</tt><a class="headerlink" href="#gcc.GimpleSwitch.indexvar" title="Permalink to this definition">¶</a></dt>
<dd><p>The index variable used by the switch statement, as a <a class="reference internal" href="tree.html#gcc.Tree" title="gcc.Tree"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Tree</span></tt></a></p>
</dd></dl>
<dl class="attribute">
<dt id="gcc.GimpleSwitch.labels">
<tt class="descname">labels</tt><a class="headerlink" href="#gcc.GimpleSwitch.labels" title="Permalink to this definition">¶</a></dt>
<dd><p>The labels of the switch statement, as a list of <a class="reference internal" href="tree.html#gcc.CaseLabelExpr" title="gcc.CaseLabelExpr"><tt class="xref py py-class docutils literal"><span class="pre">gcc.CaseLabelExpr</span></tt></a>.</p>
<p>The initial label in the list is always the default.</p>
</dd></dl>
</dd></dl>
<dl class="class">
<dt id="gcc.GimpleLabel">
<em class="property">class </em><tt class="descclassname">gcc.</tt><tt class="descname">GimpleLabel</tt><a class="headerlink" href="#gcc.GimpleLabel" title="Permalink to this definition">¶</a></dt>
<dd><blockquote>
<div><p>Subclass of <a class="reference internal" href="#gcc.Gimple" title="gcc.Gimple"><tt class="xref py py-class docutils literal"><span class="pre">gcc.Gimple</span></tt></a>, representing a “label” statement:</p>
<div class="highlight-python"><pre>LABEL:</pre>
</div>
</div></blockquote>
</dd></dl>
</div>
</div>
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