There's a buggy SIL verifier check that was previously tautological,
and it turns out that it's violated, apparently harmlessly. Since it
was already doing nothing, I've commented it out temporarily while
I figure out the right way to fix SILGen to get the invariant right.
Modeling nonescaping captures as @inout parameters is wrong, because captures are allowed to share state, unlike 'inout' parameters, which are allowed to assume to some degree that there are no aliases during the parameter's scope. To model this, introduce a new @inout_aliasable parameter convention to indicate an indirect parameter that can be written to, not only by the current function, but by well-typed, well-synchronized aliasing accesses too. (This is unrelated to our discussions of adding a "type-unsafe-aliasable" annotation to pointer_to_address to allow for safe pointer punning.)
This reflects the fact that the attribute's only for compiler-internal use, and isn't really equivalent to C's asm attribute, since it doesn't change the calling convention to be C-compatible.
At some point I want to propose a revised model for exports, but for now
just mark that support for '@exported' is still experimental and subject
to change. (Thanks, Max.)
SILPrinter was printing uses for all SIL values, except for SIL basic blocks arguments. Fill the gap and print uses for BB arguments as well. This makes reading and analyzing SIL easier.
Basic blocks may have multiple arguments, therefore print uses of each BB argument on separate lines - one line per BB argument.
The comment containing information about uses of a BB argument is printed on the line just above the basic block name, following the approach used for function_ref and other kinds of instructions, which have additional information printed on the line above the actual instruction.
The output now looks like:
// %0 // user: %3
// %1 // user: %9
bb0(%0 : $Int32, %1 : $UnsafeMutablePointer<UnsafeMutablePointer<Int8>>):
rdar://23336589
This improves support for promoting to and generating
unchecked_ref_cast so we no longer need unchecked_ref_bit_cast, which
will just go away in the next commit.
Swift SVN r32597
If the compiler can prove that a throwing function actually does not throw it can
replace a try_apply with an "apply [nothrow]". Such an apply_inst calls a function
with an error result but does not have the overhead of checking for the error case.
Currently this flag is not set, yet.
Swift SVN r31151
dealloc_ref [destructor] is the existing behavior. It expects the
reference count to have reached zero and the isDeallocating bit to
be set.
The new [constructor] variant first drops the initial strong
reference.
This allows DI to properly free uninitialized instances in
constructors. Previously this would fail with an assertion if the
runtime was built with debugging enabled.
Progress on <rdar://problem/21991742>.
Swift SVN r31142
This is mostly a "don't crash" commit, but since member XREFs don't
specify which module they're looking in, they can actually pick up
members from the module currently being compiled...which may not have
a type yet.
rdar://problem/21071045
Swift SVN r30895
Requiring a variadic parameter to come at the end of the parameter
list is an old restriction that makes no sense nowadays, and which we
had all thought we had already lifted. It made variadic parameters
unusable with trailing closures or defaulted arguments, and made our
new print() design unimplementable.
Remove this restriction, replacing it with a less onerous and slightly
less silly restriction that we not have more than one variadic
parameter in a given parameter clause. Fixes rdar://problem/20127197.
Swift SVN r30542
These variables really are local variables -- they have have a
TopLevelCodeDecl as their DeclContext rather than the SourceFile.
Treating them as global variables caused crashes in serialization.
We need an overhaul of top-level variables in script files anyway
(see rdar://problem/20992489&21628526), but this fixes the immediate
issue.
rdar://problem/21928533
Swift SVN r30519
'let' properties are settable inside certain initializers, but the
logic was wrong -- in most cases we would fall through and return
true from ::isSettable().
This came up when deserialization (correctly) didn't set the setter
accessibility on a 'let' property, and a read of that property from
a constructor in another struct incorrectly decided the property
was settable, causing a crash.
Fixes <rdar://problem/21559246>.
Swift SVN r30484
Still no implementation yet; we'll need to renovate how boxes work a bit to make them projectable (and renovate SILGen to generate typed boxes for the insn to be useful).
Swift SVN r29490
Represents a heap allocation containing a value of type T, which we'll be able to use to represent the payloads of indirect enum cases, and also improve codegen of current boxes, which generates non-uniqued box metadata on every allocation, which is dumb. No codegen changes or IRGen support yet; that will come later.
This time, fix a paste-o that caused SILBlockStorageTypes to get replaced with SILBoxTypes during type substitution. Oops.
Swift SVN r29489
This reverts commit r29475 because it conflicts with reverting r29474,
and it looks like that commit is breaking the build of the SpriteKit
overlay.
Swift SVN r29481
Still no implementation yet; we'll need to renovate how boxes work a bit to make them projectable (and renovate SILGen to generate typed boxes for the insn to be useful).
Swift SVN r29475
Represents a heap allocation containing a value of type T, which we'll be able to use to represent the payloads of indirect enum cases, and also improve codegen of current boxes, which generates non-uniqued box metadata on every allocation, which is dumb. No codegen changes or IRGen support yet; that will come later.
Swift SVN r29474
This is more complex than it could be if ExtensionDecl and NominalTypeDecl
had a common ancestor in the Decl hierarchy, however this is not possible
right now because TypeDecl inherits from ValueDecl.
Fixes <rdar://problem/20981254>.
Swift SVN r28941