LoadableByAddress was losing debug info, including at -Onone.
When converting a load-store pair to a copy_addr, the debug info
attached to the load was not salvaged.
Additionally, the wrong scope was being attached to other debug
values.
They can lower to a set of i64 registers we consider small but exploded
to (manifested as SSA) registers they will cause significant code bloat.
rdar://125265576
For years, optimizer engineers have been hitting a common bug caused by passes
assuming all SILValues have a parent function only to be surprised by SILUndef.
Generally we see SILUndef not that often so we see this come up later in
testing. This patch eliminates that problem by making SILUndef uniqued at the
function level instead of the module level. This ensures that it makes sense for
SILUndef to have a parent function, eliminating this possibility since we can
define an API to get its parent function.
rdar://123484595
Functions with c convention can have large direct arguments that are not
re-written by the LoadableByAddress pass before they get to reg2Mem
optimization.
https://github.com/apple/swift/issues/71757
In preparation for inserting mark_dependence instructions for lifetime
dependencies early, immediately after SILGen. That will simplify the
implementation of borrowed arguments.
Marking them unresolved is needed to make OSSA verification
conservative until lifetime dependence diagnostics runs.
Pattern:
%f = function_ref @invocationClosure : $@convention(thin) (BigStruct) -> ()
%s = struct $InvocationWrapper (%f : $@convention(thin) (BigStruct) -> ())
Error:
Unhandled use of FunctionRefInst
UNREACHABLE executed at /swift/lib/IRGen/LoadableByAddress.cpp:3057!
This fix simply adds the unrecognized case. Rewriting a function_ref
does not change its value, so I'm not sure why the assert exists in
the first place.
Optionally, the dependency to the initialization of the global can be specified with a dependency token `depends_on <token>`.
This is usually a `builtin "once"` which calls the initializer for the global variable.
The dependent 'value' may be marked 'nonescaping', which guarantees that the
lifetime dependence is statically enforceable. In this case, the compiler
must be able to follow all values forwarded from the dependent 'value', and
recognize all final (non-forwarded, non-escaping) use points. This implies
that `findPointerEscape` is false. A diagnostic pass checks that the
incoming SIL to verify that these use points are all initially within the
'base' lifetime. Regular 'mark_dependence' semantics ensure that
optimizations cannot violate the lifetime dependence after diagnostics.
I am doing this in preparation for adding options to SILParameterInfo/
SILResultInfo that state that a parameter/result is transferring. Even though I
could have just introduced a new bit here, I instead streamlined the interface
of SILParameterInfo/SILResultInfo to use an OptionSet instead of individual bits
to make it easier to add new flags here. The reason why it is easier is that
along API (e.x.: function argument) boundaries one does not have to marshal each
field or pass each field. Instead one can just pass the whole OptionSet as an
opaque thing. Using this I was able to change serialization/deserialization of
SILParameterInfo/SILResultInfo so that one does not need to update them if one
adds new fields!
The reason why I am doing this for both SILParameterInfo/SILResultInfo in the
same commit is because they share code in the demangler that I did not want to
have to duplicate in an intervening commit. By changing them both at the same
type, I didn't have to change anything without an actual need to.
I am doing this in a separate commit from adding transferring support so I can
validate correctness using the tests for the options already supported
(currently only differentiability).
LoadableByAddress was accidentally changing ownership of
direct_unowned values to @in (owned). This generates unsupported SIL
for on-stack partial applies, which now breaks SIL verification.
This also resulted in extra copies of values inside of closure
contexts. Before calling the original function, the value would need to
be copied onto the stack and the context would be destroyed. Now, we
simply pass a pointer directly from the closure context. See
IRGen/indirect_argument.sil+huge_partial_application.
I'm pretty sure fixing this has no effect on the mangling of public symbols.
The `bare` attribute indicates that the object header is not used throughout the lifetime of the value.
This means, no reference counting operations are performed on the object and its metadata is not used.
The header of bare objects doesn't need to be initialized.
We missed converting such types inside static initializers of global variables.
This results in ptrauth crashes when ptrauth is enabled.
rdar://108165425
This patch replaces the stateful generation of SILScope information in
SILGenFunction with data derived from the ASTScope hierarchy, which should be
100% in sync with the scopes needed for local variables. The goal is to
eliminate the surprising effects that the stack of cleanup operations can have
on the current state of SILBuilder leading to a fully deterministic (in the
sense of: predictible by a human) association of SILDebugScopes with
SILInstructions. The patch also eliminates the need to many workarounds. There
are still some accomodations for several Sema transformation passes such as
ResultBuilders, which don't correctly update the source locations when moving
around nodes. If these were implemented as macros, this problem would disappear.
This necessary rewrite of the macro scope handling included in this patch also
adds proper support nested macro expansions.
This fixes
rdar://88274783
and either fixes or at least partially addresses the following:
rdar://89252827
rdar://105186946
rdar://105757810
rdar://105997826
rdar://105102288
instead of bitcasting the original type. Once the original tuple value is
rewritten, the projected element will be the type we want, so the
original instruction would be invalid anyway, and we can make
a new instruction with the correct type directly.
It confused the original type's substituted generic signature for the new
type's invocation generic signature, leading to corrupted SIL when a
function had a substituted SIL function type with a return type involving
large loadable types that have to be passed indirectly in IR.
Fixes rdar://87792152
This change separates out the formation of the generic signature and
substitutions for a SIL substituted function type as a pre-pass
before doing the actual function type lowering. The only input we
really need to form this signature is the original abstraction pattern
that a type is being lowered against, and pre-computing it should make
the code less side-effecty and confusing. It also allows us to handle
generic nominal types in a more robust way; we transfer over all of
the nominal type requirements to the generalized generic signature,
then when recursively visiting the bindings, we same-type-constrain
the generic parameters used in those requirements to the newly-generalized
generic arguments. This ensures that the minimized signature preserves
any non-trivial requirements imposed by the nominal type, such as
conditional conformances on its type arguments, same-type constraints
among associated types, etc.
This approach does lead to less-than-optimal generalized generic
signatures getting generated, since nominal type generic arguments
get same-type-bound either to other generic arguments or fixed to
concrete types almost always. It would be useful to do a minimization
pass on the final generic signature to eliminate these unnecessary
generic arguments, but that can be done in a follow-up PR.
The code to handle yield instructions must be done earlier in `rewriteFunction` because it can add more instructions to the data structures, which also needs to be processed in `rewriteFunction`.
https://bugs.swift.org/browse/SR-14994
rdar://77526343
Instead, put the archetype->instrution map into SIlModule.
SILOpenedArchetypesTracker tried to maintain and reconstruct the mapping locally, e.g. during a use of SILBuilder.
Having a "global" map in SILModule makes the whole logic _much_ simpler.
I'm wondering why we didn't do this in the first place.
This requires that opened archetypes must be unique in a module - which makes sense. This was the case anyway, except for keypath accessors (which I fixed in the previous commit) and in some sil test files.
Refactor SILGen's ApplyOptions into an OptionSet, add a
DoesNotAwait flag to go with DoesNotThrow, and sink it
all down into SILInstruction.h.
Then, replace the isNonThrowing() flag in ApplyInst and
BeginApplyInst with getApplyOptions(), and plumb it
through to TryApplyInst as well.
Set the flag when SILGen emits a sync call to a reasync
function.
When set, this disables the SIL verifier check against
calling async functions from sync functions.
Finally, this allows us to add end-to-end tests for
rdar://problem/71098795.
My goal was to reduce the size of SILLocation. It now contains only of a storage union, which is basically a pointer and a bitfield containing the Kind, StorageKind and flags. By far, most locations are only single pointers to an AST node. For the few cases where more data needs to be stored, this data is allocated separately: with the SILModule's bump pointer allocator.
While working on this, I couldn't resist to do a major refactoring to simplify the code:
* removed unused stuff
* The term "DebugLoc" was used for 3 completely different things:
- for `struct SILLocation::DebugLoc` -> renamed it to `FilePosition`
- for `hasDebugLoc()`/`getDebugSourceLoc()` -> renamed it to `hasASTNodeForDebugging()`/`getSourceLocForDebugging()`
- for `class SILDebugLocation` -> kept it as it is (though, `SILScopedLocation` would be a better name, IMO)
* made SILLocation more "functional", i.e. replaced some setters with corresponding constructors
* replaced the hand-written bitfield `KindData` with C bitfields
* updated and improved comments
This makes it easier to understand conceptually why a ValueOwnershipKind with
Any ownership is invalid and also allowed me to explicitly document the lattice
that relates ownership constraints/value ownership kinds.
