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<p class="MsoNormal">Hi all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does LLVM currently have any way to exploit known register usage of already-compiled callee functions within a module to reduce register pressure in calling functions? GCC does this, but I haven’t seen any sign of this being done (having
checked on a couple of different target architectures), and can’t find any mention of such optimisation in the source.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Have I overlooked something? Or is there a rationale for not attempting this? (Such as limiting potential parallelism in compiling a module)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks!<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-- <o:p></o:p></p>
<p class="MsoNormal">Colin <o:p></o:p></p>
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