Ownership is truly a property not of a declaration, but of a function body. So
it makes sense to just match what we deserialize.
This also helps us to avoid mismatches if we lower ownership from a function,
delete it, and then relink it.
I also used this as an opportunity to clean up where we set that flag in
deserialization to only happen in one place for both declarations/definitions.
This indicates that the "self" argument to the current function is always dynamically of the exact
static base class type, allowing metadata accesses in IRGen to use the local self metadata to answer
metadata requests for the class type. Set this attribute on allocating entry points of designated
inits, which is one of the most common places where we emit redundant metadata accesses.
Assign separate SILProfiler instances to stored property initializers
and constructors.
Starting with rdar://39460313, coverage reporting for these constructs
was bundled up into a single SILProfiler uniqued by the NominalTypeDecl.
There are two problems with doing this.
First, the shared SILProfiler is given a fake name that can't be
demangled. That breaks Xcode's reports. Second, the relationship
between SILProfiler and SILFunction is supposed to be 1:1. Having a
shared SILProfiler muddies things a bit and requires extra bookkeeping.
rdar://47467864
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
SIL passes were violating the existing invariant on non-cond-br
critical edges in several places. I fixed the places that I could
find. Wherever there was a post-pass to "clean up" critical edges, I
replaced it with a a call to verification that the critical edges
aren't broken in the first place.
We still need to eliminate critical edges entirely before enabling
ownership SIL.
ConvertFunction and reabstraction thunks need this attribute. Otherwise,
there is no way to identify that withoutActuallyEscaping was used
to explicitly perform a conversion.
The destination of a [without_actually_escaping] conversion always has
an escaping function type. The source may have either an escaping or
@noescape function type. The conversion itself may be a nop, and there
is nothing distinctive about it. The thing that is special about these
conversions is that the source function type may have unboxed
captures. i.e. they have @inout_aliasable parameters. Exclusivity
requires that the compiler enforce a SIL data flow invariant that
nonescaping closures with unboxed captures can never be stored or
passed as an @escaping function argument. Adding this attribute allows
the compiler to enforce the invariant in general with an escape hatch
for withoutActuallyEscaping.
This commit does not modify those APIs or their usage. It just:
1. Moves the APIs onto SILFunctionBuilder and makes SILFunctionBuilder a friend
of SILModule.
2. Hides the APIs on SILModule so all users need to use SILFunctionBuilder to
create/destroy functions.
I am doing this in order to allow for adding/removing function notifications to
be enforced via the type system in the SILOptimizer. In the process of finishing
off CallerAnalysis for FSO, I discovered that we were not doing this everywhere
we need to. After considering various other options such as:
1. Verifying after all passes that the notifications were sent correctly and
asserting. Turned out to be expensive.
2. Putting a callback in SILModule. This would add an unnecessary virtual call.
I realized that by using a builder we can:
1. Enforce that users of SILFunctionBuilder can only construct composed function
builders by making the composed function builder's friends of
SILFunctionBuilder (notice I did not use the word subclass, I am talking
about a pure composition).
2. Refactor a huge amount of code in SILOpt/SILGen that involve function
creation onto a SILGenFunctionBuilder/SILOptFunctionBuilder struct. Many of
the SILFunction creation code in question are straight up copies of each
other with small variations. A builder would be a great way to simplify that
code.
3. Reduce the size of SILModule.cpp by 25% from ~30k -> ~23k making the whole
file easier to read.
NOTE: In this commit, I do not hide the constructor of SILFunctionBuilder since
I have not created the derived builder structs yet. Once I have created those in
a subsequent commit, I will hide that constructor.
rdar://42301529
The "subclass scope" is meant to represent a connection to a vtable (and how
public something needs to be), for things that end up in class
vtables. Specializations and thunks are mostly internal implementation details
and do not end up there, so subclass scope is not applicable to them. This stops
the thunks and specializations being incorrectly public.
(Note, there are some thunks that _are_ public facing: if a function has its
signature optimized, the original entry point becomes a thunk, and this entry
point is what ends up in vtables etc., so needs to remain around, which means
keeping the same hacks for `private` members of an `open` class.)
Fixes rdar://problem/40738913.
Signature optimization is slightly different to (most) other thunks, in that
it's taking an existing function and turning that into a thunk, rather than
creating a thunk that calls an existing function. These symbols can be public,
etc. and so need to be handled a bit different to other types of thunks.
@effects is too low a level, and not meant for general usage outside
the standard library. Therefore it deserves to be underscored like
other such attributes.
Replace two prominent uses of SubstitutionList, in ConcreteDeclRef and
Witness, with SubstitutionMap. Deal with the myriad places where we
now have substitution maps and need substitution lists (or vice versa)
caused by this change.
Overall, removes ~50 explicit uses of SubstitutionList (of ~400).
The ASTs for functions which aren't definitions may not be fully
typechecked or well-formed, so: avoid looking at them.
This fixes at least one assertion failure seen while building a project
with coverage, and is probably good for some substantial compile-time
improvements with coverage enabled.
rdar://39069115
This is mostly intended to be used for testing at this point; in the
long run, we want to be using availability information to decide
whether to weak-link something or not. You'll notice a bunch of FIXMEs
in the test case that we may not need now, but will probably need to
handle in the future.
Groundwork for doing backward-deployment execution tests.
We need to be able to detect function definitions that have been
deserialized. There's no need to rerun diagnostics on those functions,
and in some cases it's actually incorrect to do so. With exclusivity,
we could even miscompile in theory (debug assert) because the fully
optimized SIL does adhere to rules requires by the
diagnostic. Hopefully that specific issue can be fixed soon, but the
point is that we need control over the order that passes are run
because we play these games all the time. Not to mention the wasted
compilation time.
It would probably be sufficient to check isAvailableExternally. However, using
an explicit flag is, well, more explicit. It also generalizes to serializing IR
at any stage.
Note: I would strongly prefer not to rely on this flag for correctness. In
principle, serialized SIL should be compatible with all SIL stages prior to the
serialization point. However, it is necessary to fix bugs in the short term, and
useful for bootstrapping SIL changes in general. Also, it formalizes some
assumptions about the way the pass pipeline is expected to work making it easier
to reason about and avoid pass ordering bugs. In particular, we should not be
relying on a second round of the mandatory pass pipeline to catch important
performance opportunities.
This is a step towards being able to report coverage for closures in
member initializer expressions. These closures do not inherit a
profiler, so they need a fresh one.
We currently treat initializer expressions which aren't closures as a
part of the constructor. This doesn't work for closures because the
constructor's profiler may not be available at the time the closure is
created.
This patch moves the ownership of profiling state from SILGenProfiling
to SILFunction, where it always belonged. Similarly, it moves ownership
of the profile reader from SILGenModule to SILModule.
The refactor sets us up to fix a few outstanding code coverage bugs and
does away with sad hacks like ProfilerRAII. It also allows us to locally
guarantee that a profile counter increment actually corresponds to the
SILFunction at hand.
That local guarantee causes a bugfix to accidentally fall out of this
refactor: we now set up the profiling state for delayed functions
correctly. Previously, we would set up a ProfilerRAII for the delayed
function, but its counter increment would never be emitted :(. This fix
constitutes the only functional change in this patch -- the rest is NFC.
As a follow-up, I plan on removing some dead code in the profiling
logic and fixing a few naming inconsistencies. I've left that for later
to keep this patch simple.
This patch moves the ownership of profiling state from SILGenProfiling
to SILFunction, where it always belonged. Similarly, it moves ownership
of the profile reader from SILGenModule to SILModule.
The refactor sets us up to fix a few outstanding code coverage bugs and
does away with sad hacks like ProfilerRAII. It also allows us to locally
guarantee that a profile counter increment actually corresponds to the
SILFunction at hand.
That local guarantee causes a bugfix to accidentally fall out of this
refactor: we now set up the profiling state for delayed functions
correctly. Previously, we would set up a ProfilerRAII for the delayed
function, but its counter increment would never be emitted :(. This fix
constitutes the only functional change in this patch -- the rest is NFC.
As a follow-up, I plan on removing some dead code in the profiling
logic and fixing a few naming inconsistencies. I've left that for later
to keep this patch simple.
We can just !SILFunction::hasQualifiedOwnership(). Plus as Andy pointed out,
even ignoring the functional aspects, having APIs with names this close can
create confusion.
This commit is mostly refactoring.
*) Introduce a new OptimizationMode enum and use that in SILOptions and IRGenOptions
*) Allow the optimization mode also be specified for specific SILFunctions. This is not used in this commit yet and thus still a NFC.
Also, fixes a minor bug: we didn’t run mandatory IRGen passes for functions with @_semantics("optimize.sil.never")
@_silgen_name and @_cdecl functions are assumed to be referenced from
C code. Public and internal functions marked as such must not be deleted
by the optimizer, and their C symbols must be public or hidden respectively.
rdar://33924873, SR-6209