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<p class="MsoNormal">I’d like to generate an indirect call instruction that will end up as a call via memory and not register.<o:p></o:p></p>
<p class="MsoNormal">The address of the target is a constant.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">For example, something like<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">%25 = load i64, i64* @get_Now<o:p></o:p></p>
<p class="MsoNormal">%26 = inttoptr i64 %25 to i64 ()*<o:p></o:p></p>
<p class="MsoNormal">%27 = call i64 %26()<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">may end up as<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">mov rsi,qword ptr [00007FF658381070]<o:p></o:p></p>
<p class="MsoNormal">call rsi<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">or as<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">call qword ptr [00007FF658381070]<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If I want to guarantee that the second form is always used, how would I go about that?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">One possibility is to use patchpoints (<a href="http://llvm.org/docs/StackMaps.html#id9">http://llvm.org/docs/StackMaps.html#id9</a>). Are there any other alternatives?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Eugene<o:p></o:p></p>
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