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| <h3 class="section">7.83 <code>.p2align[wl] </code><var>abs-expr</var><code>, </code><var>abs-expr</var><code>, </code><var>abs-expr</var></h3> |
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| <p><a name="index-padding-the-location-counter-given-a-power-of-two-413"></a><a name="index-g_t_0040code_007bp2align_007d-directive-414"></a>Pad the location counter (in the current subsection) to a particular |
| storage boundary. The first expression (which must be absolute) is the |
| number of low-order zero bits the location counter must have after |
| advancement. For example ‘<samp><span class="samp">.p2align 3</span></samp>’ advances the location |
| counter until it a multiple of 8. If the location counter is already a |
| multiple of 8, no change is needed. |
| |
| <p>The second expression (also absolute) gives the fill value to be stored in the |
| padding bytes. It (and the comma) may be omitted. If it is omitted, the |
| padding bytes are normally zero. However, on some systems, if the section is |
| marked as containing code and the fill value is omitted, the space is filled |
| with no-op instructions. |
| |
| <p>The third expression is also absolute, and is also optional. If it is present, |
| it is the maximum number of bytes that should be skipped by this alignment |
| directive. If doing the alignment would require skipping more bytes than the |
| specified maximum, then the alignment is not done at all. You can omit the |
| fill value (the second argument) entirely by simply using two commas after the |
| required alignment; this can be useful if you want the alignment to be filled |
| with no-op instructions when appropriate. |
| |
| <p><a name="index-g_t_0040code_007bp2alignw_007d-directive-415"></a><a name="index-g_t_0040code_007bp2alignl_007d-directive-416"></a>The <code>.p2alignw</code> and <code>.p2alignl</code> directives are variants of the |
| <code>.p2align</code> directive. The <code>.p2alignw</code> directive treats the fill |
| pattern as a two byte word value. The <code>.p2alignl</code> directives treats the |
| fill pattern as a four byte longword value. For example, <code>.p2alignw |
| 2,0x368d</code> will align to a multiple of 4. If it skips two bytes, they will be |
| filled in with the value 0x368d (the exact placement of the bytes depends upon |
| the endianness of the processor). If it skips 1 or 3 bytes, the fill value is |
| undefined. |
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