Refactor the MemFlags
internal representation
#8162
Merged
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This commit refactors the internal
MemFlags
bits to be not just flags.Instead some bits are now grouped together and interpreted as a unit.
This enables two primary API changes:
First the
heap
/table
/vmctx
split is now represented as an "aliasregion" which is set as an enum. This means that all
MemFlags
carryan
Option<AliasRegion>
internally.Second trapping state is now represented as an
Option<TrapCode>
.This means that
notrap
is no longer a flag andtabletrap
is nolonger a flag. This does enable storing arbitrary trap codes though so
long as they aren't
TrapCode::User(_)
.The main purpose of this commit is to enable using more trap codes with
MemFlags
for when a segfault is detected. For example with #5291 wewant a segfault to indicate a call-to-null, which is not currently
covered by
MemFlags
.