Replaces page fault triggers with assembly #15053
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elad335
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Maybe instead, do T value; // Unspecified value |
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Wouldn't that just trigger read fault in most cases? |
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Fixes #14949.
Clang optimizes vm::_ref<atomic_t>(test / 4096 == begin / 4096 ? begin : test) += 0; to a simple memory barrier as it considers it's the only possible side effect:
I added a function with inline assembly to make sure it's not optimized away with a fallback to a volatile value that shouldn't be optimized away either.