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| <a name="Declarations-2"></a> |
| <h3 class="section">13.14 Declarations</h3> |
| <a name="index-RTL-declarations"></a> |
| <a name="index-declarations_002c-RTL"></a> |
| |
| <p>Declaration expression codes do not represent arithmetic operations |
| but rather state assertions about their operands. |
| </p> |
| <dl compact="compact"> |
| <dd><a name="index-strict_005flow_005fpart"></a> |
| <a name="index-subreg_002c-in-strict_005flow_005fpart"></a> |
| </dd> |
| <dt><code>(strict_low_part (subreg:<var>m</var> (reg:<var>n</var> <var>r</var>) 0))</code></dt> |
| <dd><p>This expression code is used in only one context: as the destination operand of a |
| <code>set</code> expression. In addition, the operand of this expression |
| must be a non-paradoxical <code>subreg</code> expression. |
| </p> |
| <p>The presence of <code>strict_low_part</code> says that the part of the |
| register which is meaningful in mode <var>n</var>, but is not part of |
| mode <var>m</var>, is not to be altered. Normally, an assignment to such |
| a subreg is allowed to have undefined effects on the rest of the |
| register when <var>m</var> is less than a word. |
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