Some small deinit-barrier related optimizations #81159
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eeckstein
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| // We can ignore any memory writes in a program termination point, because it's not relevant | ||
| // for the caller. But we need to consider memory reads, otherwise preceding memory writes | ||
| // would be eliminated by dead-store-elimination in the caller. | ||
| return GlobalEffects(memory: Memory(read: memory.read)) |
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Is it valid to have isDeinitBarrier as false for such functions by default ?
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Yes, it should be valid. "Program termination point" functions are functions like fatalError and exit. They are not accessing objects (except strings).
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can you add that as a comment ?
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…fined in the same module This case was neglected. The fix can result in better side effect analysis, e.g. in the stdlib core module.
…, even if library evolution is turned on. This is possible because no copy of the function is emitted in the original module.
This API already existed in Swift, but not in the C++ SIL.
…he inlined function is not a deinit barrier. There is no need to do so. And this can enable other optimizations for non-lexical alloc-stacks.
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This PR contains a few small optimization improvements which help to reduce the optimization limitations of lexical lifetimes and deinit barriers.
alloc_stackif the inlined function is not a deinit barrier. There is no need to do so. And this can enable other optimizations for non-lexical alloc-stacks.@alwaysEmitIntoClientfunctions, even if library evolution is turned on. This is possible because no copy of the function is emitted in the original module.