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| <a name="Statement-and-operand-traversals"></a> |
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| Previous: <a href="Adding-a-new-GIMPLE-statement-code.html#Adding-a-new-GIMPLE-statement-code" accesskey="p" rel="prev">Adding a new GIMPLE statement code</a>, Up: <a href="GIMPLE.html#GIMPLE" accesskey="u" rel="up">GIMPLE</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> |
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| <a name="Statement-and-operand-traversals-1"></a> |
| <h3 class="section">11.11 Statement and operand traversals</h3> |
| <a name="index-Statement-and-operand-traversals"></a> |
| |
| <p>There are two functions available for walking statements and |
| sequences: <code>walk_gimple_stmt</code> and <code>walk_gimple_seq</code>, |
| accordingly, and a third function for walking the operands in a |
| statement: <code>walk_gimple_op</code>. |
| </p> |
| <dl> |
| <dt><a name="index-walk_005fgimple_005fstmt"></a>GIMPLE function: <em>tree</em> <strong>walk_gimple_stmt</strong> <em>(gimple_stmt_iterator *gsi, walk_stmt_fn callback_stmt, walk_tree_fn callback_op, struct walk_stmt_info *wi)</em></dt> |
| <dd><p>This function is used to walk the current statement in <code>GSI</code>, |
| optionally using traversal state stored in <code>WI</code>. If <code>WI</code> is <code>NULL</code>, no |
| state is kept during the traversal. |
| </p> |
| <p>The callback <code>CALLBACK_STMT</code> is called. If <code>CALLBACK_STMT</code> returns |
| true, it means that the callback function has handled all the |
| operands of the statement and it is not necessary to walk its |
| operands. |
| </p> |
| <p>If <code>CALLBACK_STMT</code> is <code>NULL</code> or it returns false, <code>CALLBACK_OP</code> is |
| called on each operand of the statement via <code>walk_gimple_op</code>. If |
| <code>walk_gimple_op</code> returns non-<code>NULL</code> for any operand, the remaining |
| operands are not scanned. |
| </p> |
| <p>The return value is that returned by the last call to |
| <code>walk_gimple_op</code>, or <code>NULL_TREE</code> if no <code>CALLBACK_OP</code> is specified. |
| </p></dd></dl> |
| |
| |
| <dl> |
| <dt><a name="index-walk_005fgimple_005fop"></a>GIMPLE function: <em>tree</em> <strong>walk_gimple_op</strong> <em>(gimple stmt, walk_tree_fn callback_op, struct walk_stmt_info *wi)</em></dt> |
| <dd><p>Use this function to walk the operands of statement <code>STMT</code>. Every |
| operand is walked via <code>walk_tree</code> with optional state information |
| in <code>WI</code>. |
| </p> |
| <p><code>CALLBACK_OP</code> is called on each operand of <code>STMT</code> via <code>walk_tree</code>. |
| Additional parameters to <code>walk_tree</code> must be stored in <code>WI</code>. For |
| each operand <code>OP</code>, <code>walk_tree</code> is called as: |
| </p> |
| <div class="smallexample"> |
| <pre class="smallexample">walk_tree (&<code>OP</code>, <code>CALLBACK_OP</code>, <code>WI</code>, <code>PSET</code>) |
| </pre></div> |
| |
| <p>If <code>CALLBACK_OP</code> returns non-<code>NULL</code> for an operand, the remaining |
| operands are not scanned. The return value is that returned by |
| the last call to <code>walk_tree</code>, or <code>NULL_TREE</code> if no <code>CALLBACK_OP</code> is |
| specified. |
| </p></dd></dl> |
| |
| |
| <dl> |
| <dt><a name="index-walk_005fgimple_005fseq"></a>GIMPLE function: <em>tree</em> <strong>walk_gimple_seq</strong> <em>(gimple_seq seq, walk_stmt_fn callback_stmt, walk_tree_fn callback_op, struct walk_stmt_info *wi)</em></dt> |
| <dd><p>This function walks all the statements in the sequence <code>SEQ</code> |
| calling <code>walk_gimple_stmt</code> on each one. <code>WI</code> is as in |
| <code>walk_gimple_stmt</code>. If <code>walk_gimple_stmt</code> returns non-<code>NULL</code>, the walk |
| is stopped and the value returned. Otherwise, all the statements |
| are walked and <code>NULL_TREE</code> returned. |
| </p></dd></dl> |
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