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<h3 class="section"><code>ld</code> and the H8/300</h3>



   <p>For the H8/300, <code>ld</code> can perform these global optimizations when

you specify the <code>--relax</code> command-line option.



     <dl>

<dt><em>relaxing address modes</em>

     <dd><code>ld</code> finds all <code>jsr</code> and <code>jmp</code> instructions whose

targets are within eight bits, and turns them into eight-bit

program-counter relative <code>bsr</code> and <code>bra</code> instructions,

respectively.



     <br><dt><em>synthesizing instructions</em>

     <dd><code>ld</code> finds all <code>mov.b</code> instructions which use the

sixteen-bit absolute address form, but refer to the top

page of memory, and changes them to use the eight-bit address form. 

(That is: the linker turns <code>mov.b @</code><var>aa</var><code>:16</code> into

<code>mov.b @</code><var>aa</var><code>:8</code> whenever the address <var>aa</var> is in the

top page of memory). 

</dl>



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