Previously type sizes would be inconsistently sourced from either the LLVM type
or the FixedTypeInfo, depending on the call site. This was problematic because
TypeInfo operates with a resolution of whole bytes, which means that types such
as i1 would get a reported as having a size of 8. This patch now asserts that
all occurrences of the same type have the same size as the first, cached
occurence.
To avoid triggering the cached type verification assertion, this patch avoids
caching of storage-sized containers. It also removes the unique identifier from
forward declarations, which could lead to type confusion during LTO.
rdar://102367872
instead of using name and decl context.
The advantages of this approach are three-fold:
- This is necessary to support inlined generic functions.
- We can retire the debugger-specific type name manfgling mode for archetypes.
- This saves 270kb of debug information in the x86_64 libSwiftCore.dylib alone.
<rdar://problem/38306256>