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<p class="MsoNormal">I’m trying to incorporate thinLTO into our proprietary linker. I can’t seem to make it work at all (although I do have the ‘thick’ form working). When I try to invoke the ThinGenerator API it crashes somewhere way down in the bowels of
IPO. So stepping away from the linker, I am just trying to explore the processing steps using standalone off-the shelf llvm built from tip-of-tree.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">1. When I do ‘clang -c -flto=thin t1.c’ on a simple input file, the resulting .o file is a bitcode file as expected, but when I llvm-dis it there is no evidence of the module summary information. Is there a way to view the summary index
for a given module?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">2. When I take two or three .o files generated using -flto=thin and pass them to the standalone llvm-lto tool, as in:<o:p></o:p></p>
<p class="MsoNormal"> llvm-lto --thinlto t2.o t3.o --exported-symbol=t2 -o index<o:p></o:p></p>
<p class="MsoNormal">the combined index is (apparently) empty.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">3. When I take a program and pass all the .o files to llvm-lto --thinlto-action=run, I get recompiled .o files for each but there seems to be no IPO (no inlining, etc).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">What am I missing?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">-Alan<o:p></o:p></p>
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