[capture-promotion] When checking if a (struct_element_addr (project_box box)) is written to, check that all of the operands are loads, instead of returning early when we find one. #10270
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…box box)) is written to, check that all of the operands are loads, instead of returning early when we find one. I found this bug by inspection. This is an important bug to fix since this pass runs at -Onone and the bug results in the compiler hitting an unreachable. The way the unreachable is triggered is that when we detect that we are going to promote a box, if we see a (struct_element_addr (project_box box)), we don't map the struct_element_addr to a cloned value. If we have a load, this is not an issue, since we are mapping the load to the struct_extract. But if we have /any/ other non-load users of the struct_element_addr, the cloner will attempt to look up the struct_element_addr and will be unable to find it, hitting an unreachable. rdar://32776202
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@swift-ci smoke test and merge |
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@shahmishal Sorry. Forgot that you were updating the CI! |
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@swift-ci smoke test and merge |
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[capture-promotion] When checking if a (struct_element_addr (project_box box)) is written to, check that all of the operands are loads, instead of returning early when we find one.
I found this bug by inspection.
This is an important bug to fix since this pass runs at -Onone and the bug
results in the compiler hitting an unreachable.
The way the unreachable is triggered is that when we detect that we are going to
promote a box, if we see a (struct_element_addr (project_box box)), we don't map
the struct_element_addr to a cloned value. If we have a load, this is not an
issue, since we are mapping the load to the struct_extract. But if we have /any/
other non-load users of the struct_element_addr, the cloner will attempt to look
up the struct_element_addr and will be unable to find it, hitting an
unreachable.
rdar://32776202