Type annotations for instruction operands are omitted, e.g.
```
%3 = struct $S(%1, %2)
```
Operand types are redundant anyway and were only used for sanity checking in the SIL parser.
But: operand types _are_ printed if the definition of the operand value was not printed yet.
This happens:
* if the block with the definition appears after the block where the operand's instruction is located
* if a block or instruction is printed in isolation, e.g. in a debugger
The old behavior can be restored with `-Xllvm -sil-print-types`.
This option is added to many existing test files which check for operand types in their check-lines.
Most of this patch is just removing special cases for materializeForSet
or other fairly mechanical replacements. Unfortunately, the rest is
still a fairly big change, and not one that can be easily split apart
because of the quite reasonable reliance on metaprogramming throughout
the compiler. And, of course, there are a bunch of test updates that
have to be sync'ed with the actual change to code-generation.
This is SR-7134.
The SILGen testsuite consists of valid Swift code covering most language
features. We use these tests to verify that no unknown nodes are in the
file's libSyntax tree. That way we will (hopefully) catch any future
changes or additions to the language which are not implemented in
libSyntax.
conversions that reverse an implicit conversion done to align
foreign declarations with their imported types.
For example, consider an Objective-C method that returns an NSString*:
- (nonnull NSString*) foo;
This will be imported into Swift as a method returning a String:
func foo() -> String
A call to this method will implicitly convert the result to String
behind the scenes. If the user then casts the result back to NSString*,
that would normally be compiled as an additional conversion. The
compiler cannot simply eliminate the conversion because that is not
necessarily semantically equivalent.
This peephole recognizes as-casts that immediately reverse a bridging
conversion as a special case and gives them special power to eliminate
both conversions. For example, 'foo() as NSString' will simply return
the original return value. In addition to call results, this also
applies to call arguments, property accesses, and subscript accesses.
Keep in mind that these are approximations that will not impact correctness
since in all cases I ensured that the SIL will be the same after the
OwnershipModelEliminator has run. The cases that I was unsure of I commented
with SEMANTIC ARC TODO. Once we have the verifier any confusion that may have
occurred here will be dealt with.
rdar://28685236
Similarly to how we've always handled parameter types, we
now recursively expand tuples in result types and separately
determine a result convention for each result.
The most important code-generation change here is that
indirect results are now returned separately from each
other and from any direct results. It is generally far
better, when receiving an indirect result, to receive it
as an independent result; the caller is much more likely
to be able to directly receive the result in the address
they want to initialize, rather than having to receive it
in temporary memory and then copy parts of it into the
target.
The most important conceptual change here that clients and
producers of SIL must be aware of is the new distinction
between a SILFunctionType's *parameters* and its *argument
list*. The former is just the formal parameters, derived
purely from the parameter types of the original function;
indirect results are no longer in this list. The latter
includes the indirect result arguments; as always, all
the indirect results strictly precede the parameters.
Apply instructions and entry block arguments follow the
argument list, not the parameter list.
A relatively minor change is that there can now be multiple
direct results, each with its own result convention.
This is a minor change because I've chosen to leave
return instructions as taking a single operand and
apply instructions as producing a single result; when
the type describes multiple results, they are implicitly
bound up in a tuple. It might make sense to split these
up and allow e.g. return instructions to take a list
of operands; however, it's not clear what to do on the
caller side, and this would be a major change that can
be separated out from this already over-large patch.
Unsurprisingly, the most invasive changes here are in
SILGen; this requires substantial reworking of both call
emission and reabstraction. It also proved important
to switch several SILGen operations over to work with
RValue instead of ManagedValue, since otherwise they
would be forced to spuriously "implode" buffers.
For long names this is easier to read and in most cases the omitted information can be seen in the actual SIL code.
With the option -Xllvm -sil-full-demangle the old behavior can be restored.
Having a separate address and container value returned from alloc_stack is not really needed in SIL.
Even if they differ we have both addresses available during IRGen, because a dealloc_stack is always dominated by the corresponding alloc_stack in the same function.
Although this commit quite large, most changes are trivial. The largest non-trivial change is in IRGenSIL.
This commit is a NFC regarding the generated code. Even the generated SIL is the same (except removed #0, #1 and @local_storage).
And include some supplementary mangling changes:
- Give the first generic param (depth=0, index=0) a single character mangling. Even after removing the self type from method declaration types, 'Self' still shows up very frequently in protocol requirement signatures.
- Fix the mangling of generic parameter counts to elide the count when there's only one parameter at the starting depth of the mangling.
Together these carve another 154KB out of a debug standard library. There's some awkwardness in demangled strings that I'll clean up in subsequent commits; since decl types now only mangle the number of generic params at their own depth, it's context-dependent what depths those represent, which we get wrong now. Currying markers are also wrong, but since free function currying is going away, we can mangle the partial application thunks in different ways.
Swift SVN r32896
Canonical dependent member types are always based from a generic parameter, so we can use a more optimal mangling that assumes this. We can also introduce substitutions for AssociatedTypeDecls, and when a generic parameter in a signature is constrained by a single protocol, we can leave that protocol qualification out of the unsubstituted associated type mangling. These optimizations together shrink the standard library by 117KB, and bring the length of the longest Swift symbol in the stdlib down from 578 to 334 characters, shorter than the longest C++ symbol in the stdlib.
Swift SVN r32786
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
use a thin function type.
We still need thin-function-to-RawPointer conversions
for generic code, but that's fixable with some sort of
partial_apply_thin_recoverable instruction.
Swift SVN r24364
optional callback; retrofit existing implementations.
There's a lot of unpleasant traffic in raw pointers here
which I'm going to try to clean up.
Swift SVN r24123
Now the SILLinkage for functions and global variables is according to the swift visibility (private, internal or public).
In addition, the fact whether a function or global variable is considered as fragile, is kept in a separate flag at SIL level.
Previously the linkage was used for this (e.g. no inlining of less visible functions to more visible functions). But it had no effect,
because everything was public anyway.
For now this isFragile-flag is set for public transparent functions and for everything if a module is compiled with -sil-serialize-all,
i.e. for the stdlib.
For details see <rdar://problem/18201785> Set SILLinkage correctly and better handling of fragile functions.
The benefits of this change are:
*) Enable to eliminate unused private and internal functions
*) It should be possible now to use private in the stdlib
*) The symbol linkage is as one would expect (previously almost all symbols were public).
More details:
Specializations from fragile functions (e.g. from the stdlib) now get linkonce_odr,default
linkage instead of linkonce_odr,hidden, i.e. they have public visibility.
The reason is: if such a function is called from another fragile function (in the same module),
then it has to be visible from a third module, in case the fragile caller is inlined but not
the specialized function.
I had to update lots of test files, because many CHECK-LABEL lines include the linkage, which has changed.
The -sil-serialize-all option is now handled at SILGen and not at the Serializer.
This means that test files in sil format which are compiled with -sil-serialize-all
must have the [fragile] attribute set for all functions and globals.
The -disable-access-control option doesn't help anymore if the accessed module is not compiled
with -sil-serialize-all, because the linker will complain about unresolved symbols.
A final note: I tried to consider all the implications of this change, but it's not a low-risk change.
If you have any comments, please let me know.
Swift SVN r22215
accessors on non-dynamic storage.
This allows us to take advantage of dynamic knowledge
that a property is implemented as stored in order to
gain direct access to it instead of copying into a
temporary. When a class or protocol-member property
is expensive to copy, and particularly when it's of
copy-on-write type, such direct accesses can massively
improve the performance of a program.
We are currently only able to apply this when the
property is implemented purely as stored. A willSet
observer inherently blocks the optimization, but we
should be able to make it work even for properties
with didSet observers. This could be done by returning
an arbitrary callback from materializeForSet instead
of returning a flag indicating whether to call the
setter.
rdar://17416120
Swift SVN r22122