Both the syntax and relative order of the LLVM `nocapture` parameter
attribute changed upstream in 29441e4f5fa5f5c7709f7cf180815ba97f611297.
To reduce conflicts with rebranch, adjust FileCheck patterns to expect
both syntaxes and orders anywhere the presence of the attribute is not
critical to the test. These changes are temporary and will be cleaned
up once rebranch is merged into main.
This attribute was introduced in
7eca38ce76d5d1915f4ab7e665964062c0b37697 (llvm-project).
Match it using a wildcard regex, since it is not relevant to these
tests.
This is intended to reduce future conflicts with rebranch.
rdar://149985633
Using at least Int8 here allows LLVM to apply more optimizations, reducing code size, avoiding stack allocations and as a result often eliminating complete stack frames.
The use of 'nocapture' for parameters and return values is incorrect for C++ types, as they can actually capture a pointer into its own value (e.g. std::string in libstdc++)
rdar://115062687
The Swift Simplification pass can do more than the old MandatoryCombine pass: simplification of more instruction types and dead code elimination.
The result is a better -Onone performance while still keeping debug info consistent.
Currently following code patterns are simplified:
* `struct` -> `struct_extract`
* `enum` -> `unchecked_enum_data`
* `partial_apply` -> `apply`
* `br` to a 1:1 related block
* `cond_br` with a constant condition
* `isConcrete` and `is_same_metadata` builtins
More simplifications can be added in the future.
rdar://96708429
rdar://104562580
LLVM does type based analysis on sret storage types. This is a problem
with non-fixed types whose storage type does not contain the non-fixed
part.
rdar://73778591
Previously, the trailing flags field of runtime instantiated generic
metadata for types which had prespecialization enabled were not zeroed.
Consequently, the field always contained garbage. Often, metadata was
instantiated on new (and so, zeroed) pages, so the garbage happened to
be zero as is appropriate. However, when the metadata was instantiated
on pages which had previously been dirtied, the garbage value would
sometimes indicate that the metadata was canonical statically
specialized. When that occurred, swift_checkMetadataState would
incorrectly return a metadata state of complete, despite the fact that
the metadata might not in fact be complete. As a result, the runtime
was trafficking in incomplete metadata as if it were complete, resulting
in various crashes that would arise from for example missing a witness
table or a value witness table.
Here the problem is corrected. The trailing flags field of structs and
enums that have the field is set to 0.
For structs, this is accomplished by modifying the extra data pattern to
exist not only when there is fixed type info for the type but also when
the type is being prespecialized. Specifically, the extra data for a
struct is, rather than an i32 array of field offsets, a struct
consisting of none, one, or both of the following: (1) the array of
field offsets, (2) the trailing flags.
Similarly, enums now have an extra data pattern which consists of none,
one, or both of the following: (1) the payload size, (2) the trailing
flags. Enum metadata extra data setting was previously achieved by
customizing the metadata allocation function; that customization is now
eliminated, being replaced with the shared runtime code for copying
extra data into place, a modest code size savings.
rdar://problem/61465515
Regardless of any flags, the stdlib will have its generic metadata
prespecialized.
Temporarily reintroduced the flag to enable the feature flag while
preserving the flag to disable it and changed the default back to off
for the moment.
When a specialized usage of a generic enum occurs in the same module
where the enum was defined, directly reference the prespecialized
metadata.
rdar://problem/56994321
