It avoids generation of llvm phi nodes with identical predecessors and differing values.
This change replaces my previous fix of this problem in r23580, where I handled it in IRGen.
There were some discussions about it with the conclusion that it's better to just disallow such cond_br instructions in SIL.
It makes the life easier for some SIL optimizations which can't deal with cond_br with identical destinations.
The original radar is <rdar://problem/18568272> Swift compiler fails with "PHI node has multiple entries for the same basic block with different incoming values!"
Swift SVN r23861
Verify that witness_method instructions with a lookup type that is an
opened archetype have the optional operand that represents the
open_existential instruction.
I ran into this working supporting substitution of existential types in
mandatory inlining (rdar://problem/17769717).
Swift SVN r23665
This can arise by substitution when we specialize a generic parameter bounded by an ObjC protocol with an ObjC protocol type. Fixes rdar://problem/19035529.
Swift SVN r23463
Before this patch there was no dependence visible to the optimizer between a
open_existential and the witness_method allowing the optimizer to reorder the
two instruction. The dependence was implicit in the opened archetype but this
is not a concept model by the SIL optimizer.
%2 = open_existential %0 : $*FooProto to $*@opened("...") FooProto
%3 = witness_method $@opened("...") FooProto,
#FooProto.bar!1 : $@cc(...)
%4 = apply %3<...>(%2)
This patch changes the SIL representation such that witness_methods on opened
archetypes take the open_existential (or the producer of the opened existential)
as an operand preventing the optimizer from reordering them.
%2 = open_existential %0 : $*FooProto to $*@opened("...") FooProto
%3 = witness_method $@opened("...") FooProto,
#FooProto.bar!1,
%2 : $*@opened("...") FooProto : $@cc(...)
%4 = apply %3<...>(%2)
rdar://18984526
Swift SVN r23438
Verify that existentials have null conformances, just as is required of
archetypes, and require non-null conformances in other cases.
The last require that we had here attempted to allow for null
conformances, but we check just above that the conformance is non-null,
and this was firing on existentials with some other changes that I have.
Swift SVN r23200
The instruction isn't expressive enough to represent an arbitrary indirect cast, which may need a buffer to change the value's representation, and it looks like we don't exercise this legacy capability anymore.
Swift SVN r23130
Fixes a bug where dynamic dispatches of class methods or initializers through generic interfaces didn't redispatch to subclasses. Also fix up some logic errors noticed by inspection.
Swift SVN r22945
This is a type that has ownership of a reference while allowing access to the
spare bits inside the pointer, but which can also safely hold an ObjC tagged pointer
reference (with no spare bits of course). It additionally blesses one
Foundation-coordinated bit with the meaning of "has swift refcounting" in order
to get a faster short-circuit to native refcounting. It supports the following
builtin operations:
- Builtin.castToBridgeObject<T>(ref: T, bits: Builtin.Word) ->
Builtin.BridgeObject
Creates a BridgeObject that contains the bitwise-OR of the bit patterns of
"ref" and "bits". It is the user's responsibility to ensure "bits" doesn't
interfere with the reference identity of the resulting value. In other words,
it is undefined behavior unless:
castReferenceFromBridgeObject(castToBridgeObject(ref, bits)) === ref
This means "bits" must be zero if "ref" is a tagged pointer. If "ref" is a real
object pointer, "bits" must not have any non-spare bits set (unless they're
already set in the pointer value). The native discriminator bit may only be set
if the object is Swift-refcounted.
- Builtin.castReferenceFromBridgeObject<T>(bo: Builtin.BridgeObject) -> T
Extracts the reference from a BridgeObject.
- Builtin.castBitPatternFromBridgeObject(bo: Builtin.BridgeObject) -> Builtin.Word
Presents the bit pattern of a BridgeObject as a Word.
BridgeObject's bits are set up as follows on the various platforms:
i386, armv7:
No ObjC tagged pointers
Swift native refcounting flag bit: 0x0000_0001
Other available spare bits: 0x0000_0002
x86_64:
Reserved for ObjC tagged pointers: 0x8000_0000_0000_0001
Swift native refcounting flag bit: 0x0000_0000_0000_0002
Other available spare bits: 0x7F00_0000_0000_0004
arm64:
Reserved for ObjC tagged pointers: 0x8000_0000_0000_0000
Swift native refcounting flag bit: 0x4000_0000_0000_0000
Other available spare bits: 0x3F00_0000_0000_0007
TODO: BridgeObject doesn't present any extra inhabitants. It ought to at least provide null as an extra inhabitant for Optional.
Swift SVN r22880
terminators"
This is an assumption that the SSAUpdater makes. Verify that we preserve this
property.
With changes to the test cases, SIL documentation and add a critical edge (non
cond_br only) splitting pass to the mandatory pipeline.
This reapplies commit 22775.
Swift SVN r22803
This reverts commit r22775 as it breaks SILPasses/simplify_cfg_args.sil
and SILPasses/split_critical_edges.sil for me with:
Assertion failed: (!isCriticalEdgePred(BB.getTerminator(), Idx) && "non
cond_br critical edges not allowed"), function verify, file
/Users/dave/src/s/swift/lib/SIL/Verifier.cpp, line 2380.
Swift SVN r22780
Modeling builtins as first-class function values doesn't really make sense because there's no real function value to emit, and modeling them this way complicates passes that work with builtins because they have to invent function types for builtin invocations. It's much more straightforward to have a single instruction that references the builtin by ID, along with the type information for the necessary values, type parameters, and results, so add a new "builtin" instruction that directly represents a builtin invocation. NFC yet.
Swift SVN r22690
layouts. Introduce new SIL instructions to initialize
and open existential metatype values.
Don't actually, y'know, lift any of the restriction on
existential metatypes; just pointlessly burn extra
memory storing them.
Swift SVN r22592
Since both shared and shared_external both lower to linkonce_odr, neither of
them can be declarations. This commit puts a check into the verifier to ensure
that this does not happen at the SIL level allowing us to catch such issues
earlier.
Swift SVN r22552
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
The metatype is associated with the formal AST type of the value, not whatever lowered SIL type we happen to have lying around. Adjust the SIL verifier to check that value_metatype instructions produce a metatype for which the instance is a potential lowering rather than by exact type match. This lets us take the metatype of metatypes (and incidentally, of functions, and of tuples thereof), fixing rdar://problem/17242770.
Swift SVN r22202
This is already an assumption in SILFunctionType:
bool hasIndirectResult() const {
return !getParameters().empty()
&& getParameters()[0].isIndirectResult();
}
SILParameterInfo getIndirectResult() const {
assert(hasIndirectResult());
return getParameters()[0];
}
This just bakes the invariant into the IR so it is clear when writing tests that
this is not an issue.
I also updated function_ref and partial_apply to have the same such checks. This
should handle the majority of the cases.
Swift SVN r22119
This is necessary to be able to properly stash values with nontrivial lowerings, such as metatypes and functions, inside existential containers. Modify SILGen to lower values to the proper abstraction level before storing them in an existential container. Part of the fix for rdar://problem/18189508, though runtime problems still remain when trying to actually dynamicCast out a metatype from an Any container.
Swift SVN r21830
We want to be able to work around problems with non-failable
Objective-C initializers actually failing, which can happen when the
API audit data incorrectly marks an initializer as non-failable.
Swift SVN r21711
