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Hi.</div>
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I'm trying to use LLD to get it's input file from a string in memory instead of a file.</div>
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My use case is a JIT compiler (IR --> AMD GCN ISA) where calling the linker to make it a loadable object via system() is hitting a bug (somewhere in the system).</div>
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Here's what I do:</div>
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<li><span>With the AMDGPU backend I write the output to a string</span></li><li><span>I sneak in this string into LLD via an added access function.</span></li><li><span>Since LLD invocation is only used in this form:<br>
ld.lld -shared k.o -o k.so<br>
I modified 'elf::readFile' to</span></li></ol>
<div><span> std::string tmp = qdp_jit_get_object(); // this retrieves the sneaky string
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<div> llvm::outs() << "size = " << tmp.size() << "\n";</div>
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<div> std::unique_ptr<MemoryBuffer> mb = MemoryBuffer::getMemBuffer( StringRef( tmp.c_str() , tmp.length() ) );</div>
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<div> MemoryBufferRef mbref = mb->getMemBufferRef();</div>
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<span> return mbref;</span><br>
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When I then call LLD via lld::elf::link, I get</div>
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size = 2192
<div>ld: error: :1: unknown directive: </div>
<div>>>> A�E�A�E�@���?V@���?V�3��������}j<������� �J�0�ւ���j�</div>
<span>>>> ^</span><br>
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This is how the string containing the object was created:</div>
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string str_obj;</div>
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llvm::raw_string_ostream rss(str_obj);
<div> llvm::buffer_ostream bos(rss);</div>
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<div> if (TargetMachine->addPassesToEmitFile(CodeGenPasses, </div>
<div> bos,<br>
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<div> nullptr,</div>
<span> llvm::CodeGenFileType::CGFT_ObjectFile ))</span><br>
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<span style="color: rgb(0, 0, 0); font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt;">CodeGenPasses.run(*Mod);</span><br>
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Is there anything wrong how I turn the string into a MemoryBuffer so that the link fails?</div>
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Thanks,</div>
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Frank</div>
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