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    <p>The dudes from the LLVM mailing list were <a href="http://lists.cs.uiuc.edu/pipermail/llvmdev/2010-June/032661.html" rel="nofollow noreferrer">helpful enough to provide a better solution</a>. They didn't say how to get the pointer from the method to the function, but I've already figured out this part so it's okay.</p> <p><strong>EDIT</strong> A clean way to do this is simply to wrap your method into a function:</p> <pre><code>int Foo_Bar(Foo* foo) { return foo-&gt;bar(); } </code></pre> <p>Then use <code>Foo_Bar</code>'s address instead of trying to get <code>Foo::bar</code>'s. Use <code>llvm::ExecutionEngine::addGlobalMapping</code> to add the mapping as shown below.</p> <p>As usual, the simplest solution has some interesting benefits. For instance, it works with virtual functions without a hiccup. (But it's so much less entertaining. The rest of the answer is kept for historical purposes, mainly because I had a lot of fun poking at the internals of my C++ runtime. Also note that it's non-portable.)</p> <hr> <p>You'll need something along these lines to figure the address of a method (be warned, that's a dirty hack that probably will only be compatible with the Itanium ABI):</p> <pre><code>template&lt;typename T&gt; const void* void_cast(const T&amp; object) { union Retyper { const T object; void* pointer; Retyper(T obj) : object(obj) { } }; return Retyper(object).pointer; } template&lt;typename T, typename M&gt; const void* getMethodPointer(const T* object, M method) // will work for virtual methods { union MethodEntry { intptr_t offset; void* function; }; const MethodEntry* entry = static_cast&lt;const MethodEntry*&gt;(void_cast(&amp;method)); if (entry-&gt;offset % sizeof(intptr_t) == 0) // looks like that's how the runtime guesses virtual from static return getMethodPointer(method); const void* const* const vtable = *reinterpret_cast&lt;const void* const* const* const&gt;(object); return vtable[(entry-&gt;offset - 1) / sizeof(void*)]; } template&lt;typename M&gt; const void* getMethodPointer(M method) // will only work with non-virtual methods { union MethodEntry { intptr_t offset; void* function; }; return static_cast&lt;const MethodEntry*&gt;(void_cast(&amp;method))-&gt;function; } </code></pre> <p>Then use <code>llvm::ExecutionEngine::addGlobalMapping</code> to map a function to the address you've gotten. To call it, pass it your object as the first parameter, and the rest as usual. Here's a quick example.</p> <pre><code>class Foo { void Bar(); virtual void Baz(); }; class FooFoo : public Foo { virtual void Baz(); }; Foo* foo = new FooFoo; const void* barMethodPointer = getMethodPointer(&amp;Foo::Bar); const void* bazMethodPointer = getMethodPointer(foo, &amp;Foo::Baz); // will get FooFoo::Baz llvm::ExecutionEngine* engine = llvm::EngineBuilder(module).Create(); llvm::Function* bar = llvm::Function::Create(/* function type */, Function::ExternalLinkage, "foo", module); llvm::Function* baz = llvm::Function::Create(/* function type */, Function::ExternalLinkage, "baz", module); engine-&gt;addGlobalMapping(bar, const_cast&lt;void*&gt;(barMethodPointer)); // LLVM always takes non-const pointers engine-&gt;addGlobalMapping(baz, const_cast&lt;void*&gt;(bazMethodPointer)); </code></pre>
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    1. POCan I bind an existing method to a LLVM Function* and use it from JIT-compiled code?
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    1. COWould you mind to show us how you resolved the issue in the end. I'm struggling with the same problem.
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    2. CO@FFox: sure. I've edited the answer to provide a helpful example.
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    3. CO@zneak, in the function type you pass to `llvm::Function::Create` what type did you use for the first argument (the object pointer)? did you use void*?
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