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<p class="MsoNormal"><span lang="EN-GB">Hello LLVM-people,<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I compiled a source file - containing a string - with Clang-cl to IR and.... found my string there again, which looks like that:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">@"??_C@_1BO@NHIBMFPN@?$AAS?$AAc?$AAh?$AAw?$AAi?$AAm?$AAm?$AAf?$AAl?$AAu?$AAe?$AAg?$AAe?$AAl?$AA?$AA@" = linkonce_odr dso_local unnamed_addr constant [15 x i16] [i16 83, i16 99, i16 104, i16 119, i16 105, i16 109, i16
109, i16 102, i16 108, i16 117, i16 101, i16 103, i16 101, i16 108, i16 0], comdat, align 2<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Which should be the string "Schwimmfluegel" in Windows wchar_t. This module is later loaded and will be jitted.<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">My question is, can I modify the content of the string? Even change it from 16 bit to 32 bit (adjusting the alignment as well of course) and how would I do that?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">I'm not much familiar with editing a LLVM Module in code - but I guess the first thing is to search for the strings (or strings in general) so I would start with:<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> for(auto &global : module->globals())<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> {<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> <o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"> }<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">However... there my knowledge already stops x.x"<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Do I need to check the mangled name of my symbol to identify it as a string or does "global" provide a function for that? And then of course... how to proceed reading the string content? Writing it, extending it - changing
the underlying type?<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Any help is appreciated >o<<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB"><o:p> </o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Kind greetings<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-GB">Björn<o:p></o:p></span></p>
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