This is shorter, more closely connected to code using the typed node
types, and avoids using the ambiguous word `Node` in places referring to
typed `SemIR` nodes.
Replace `SemIR::Node::GetAsFoo` and `SemIR::Node::Foo::Make` with
`SemIR::Foo` class that represents a particular kind of node, with named
fields.
Rename `SemIR::IntegerLiteral` and `SemIR::RealLiteral` to
`IntegerValue` / `RealValue` to better reflect their purpose and avoid a
name collision with the corresponding `SemIR` node kinds.
Remove `NodeKind::Invalid` and the `SemIR::Node` default constructor
entirely, as they were not used for anything.
Also add `name_reference_untyped` for references to non-first-class
names without types, which currently covers namespaces and functions.
This improves the fidelity of the SemIR representation, and fixes some
issues where we would use the wrong location for nodes and diagnostics
downstream of a name reference.
We're still missing a representation for dotted name expressions, such
as `Namespace.Function`, and we don't use the `untyped` node as an
operand of any other node yet.
Combine the initialization, implicit conversion, and value category
conversion functions into a single function.
This substantially reduces the duplication between these steps, and
ensures that we support the same set of conversions in all these
contexts. This also fixes some issues where we would not use the proper
value representation for tuples and structs after performing implicit
conversions.
Fix a bug where we would perform the computation of the return location
in SemIR after we have already used it in some cases, leading to
assertion failures during lowering. Instead, accumulate a sequence of
instructions to compute the return location in a temporary block, and
overwrite the return slot with those instructions when we perform
initialization.
StubReference is replaced by a more general SpliceBlock node, that takes
a code block and a result value, executes the instructions in the block,
and produces the result. This is used in the uncommon case where more
than one instruction is required to compute the return slot, which can
happen if we need to first emit a temporary and then index into it, or
if we need to perform multiple levels of indexing before we reach an
entity to initialize.
Factor out the common code to find the return slot for an initializing
expression, and use it to simplify the two different ways we finalize
initializers, as either initializing a temporary or initializing some
specific object.
This slightly changes the SemIR we create for function calls: instead of
rewriting the Call node to have a different destination and replacing
its temporary with a `no_op`, we now replace its temporary with a
`stub_reference` to the new destination. This results in the same amount
of SemIR being produced, but allows calls and other kinds of
initializers to be handled uniformly.
The speculative insertion of StubReferences after elements in an
argument list turned out to not be necessary, because we decided we want
to insert per-argument initialization steps after all arguments are
evaluated, rather than interleaving them. The StubReferences we insert
are causing some minor code complexity, so remove them.
We still create StubReferences when performing patch-ups of
already-emitted code, but we no longer ever need to look through them
when determining whether an initializer was a literal or when evaluating
a type expression.
This implements initializing expression semantics for structs and
tuples, following #2006 and discussions since.
Tuple and (and analogously, struct) literals are treated as having a
mixed expression category that is later resolved based on how the
literal is used, as either a tuple initializer or a tuple value, at
which point we create a `TupleInit` or `TupleValue` that represents the
formation of the tuple initializer or tuple value from the tuple
literal.
There's quite a lot of TODOs here, and the SemIR representation is still
not quite right, but this seems like a good place to checkpoint some
incremental progress.
- `Peek()` no longer returns a useful value, because we often don't
allocate a `NodeBlockId` until we finish building the block. Remove it
and update both its callers.
- Rename `PeekForAdd()` to `PeekOrAdd()` since it's no longer used to
get a block ID to add elements into.
- `PushForAdd()` was unused. Remove it.
- Add `NodeBlockStack::AddNode` to combine the operations of adding a
node and inserting it into a block.
Instead of modeling array initialization as a thin wrapper around tuple
initialization, handle it like a function call, with a return slot as
part of its input. This better matches how initialization via a call to
`ImplicitAs::Convert` will eventually work, and in particular lets us do
in-place initialization of arrays rather than always creating a
temporary.
`SemIR` now only stores complete blocks, and placeholders for blocks
where we need a block ID before we know the block contents.
This is a preparation step towards the new node block allocation design.
This removes the risk of accidentally performing a vector copy when
calling these functions, and is a preparation step towards the new node
block allocation design.
This required changing how we build call expressions. Instead of
finishing the argument block and then later adding a return slot, we now
delay finishing the argument block and checking for conversions to
parameter types until after we've added the return slot to it.
This better reflects the purpose of these semantics nodes, and prepares
for adding TupleValue and TupleInit nodes to represent forming values
and initializers from literals.
In order to maintain diagnostic quality, add a mechanism to add notes to
any diagnostics that are produced as part of initialization of function
parameters. As suggested in review of #3205.
In passing, fix the only caller of `ImplicitAsRequired` outside of the
implementation of `Check::Context` to instead use
`ConvertToValueExpressionOfType`. This causes some missing
`value_binding` nodes to be added to the produced SemIR. Also fixed a
matching bug in lowering where a bogus load was being added, that
resulted in assertion failures when the checker bug was fixed.
The warning `-Wnon-virtual-dtor` starts producing false-positive
warnings after this change. Replace it with the fixed version,
`-Wdelete-non-virtual-dtor`.
Continuing with #3070. Just a dir and file rename (only prefix change is
lexer_file_test). Everything in the lex dir should be marked as a move.
Note, I think this closes#3070. There may still be further cleanup
later, but the organizational changes suggested there are being
completed.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
Continuing with #3070. Just a dir and file rename (mostly removing
prefixes, although for parse_tree_fuzzer and parse_tree_file_test I'm
dropping "tree" instead of "parse"). Everything in the parse dir should
be marked as a move.
Continuing along with #3070. Note this is just a file rename, with BUILD
edits; every file previously in semantics/ should show as moved (except
maybe BUILDs, which split).
Richard Smith
Jon Ross-PerkinsandChandler Carruth