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
I found the corresponding code in LLDB that depended on this hack and
am now removing both. This makes it possible to share the same code
path for top-level archetypes and member types.
rdar://problem/45462765
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>
This commit adds a DebugVariable field that is shared by
- AllocBoxInst
- AllocStackInst
- DebugValueInst
- DebugValueAddrInst
Currently DebugVariable only holds the Swift argument number.
This allows us to retire several expensive heuristics in IRGen that
attempted to identify which local variables actually where arguments
and recover their relative order.
Memory footprint notes:
This commit adds a 4-byte field to 4 SILInstructin subclasses.
This was offset by 8ab1e2dd50
which removed 20 bytes from *every* SILInstruction.
Caveats:
This commit surfaces a known bug in FunctionSigantureOpts, tracked in
rdar://problem/23727705 — debug info for exploded function arguments
cannot be expressed until this is fixed.
This reapplies ed2b16dc5a with a bugfix for
generic function arrguments and an additional testcase.
<rdar://problem/21185379&22705926>
