llvm: Switch to trampoline-based jlcall annotations #45088
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src/codegen.cpp
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| // | ||
| // ptr julia.call(ptr %fptr, ptr %f, ptr %arg1, ptr %arg2, ...) | ||
| // | ||
| // In late lowering the call then be rewritten as |
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| // In late lowering the call then be rewritten as | |
| // In late lowering the call will be rewritten as |
vchuravy
approved these changes
Apr 25, 2022
As discussed extensively in #45057, when enabling LLVM's opaque pointer support, we get significant miscompilations in jlcall callsites, because calls with mismatching calling conventions are considered undefined behavior. This implements Option D) from #45057, switching our jlcall callsites to use a `julia.call` trampoline intrinsic instead. The lowering for this intrinsic is essentially the same as the CC-based lowering before, except that the callee is now of course the first argument rather than the actual callee. Other than that, the changes are mostly mechanical. Fixes #45057
vtjnash
reviewed
Apr 28, 2022
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Remove "thunk" now from everywhere?
This LGTM. My only question is whether this will restrict optimizations in the future, since we won't be able to set function attributes on the called function target. But we will change this again later if that ever does become a real issue.
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As discussed extensively in #45057, when enabling LLVM's opaque pointer
support, we get significant miscompilations in jlcall callsites, because
calls with mismatching calling conventions are considered undefined behavior.
This implements Option D) from #45057, switching our jlcall callsites to use
a
julia.calltrampoline intrinsic instead. The lowering for this intrinsicis essentially the same as the CC-based lowering before, except that the
callee is now of course the first argument rather than the actual callee.
Other than that, the changes are mostly mechanical.
Fixes #45057