- Only allow assignment at the top level in an expression statement.
- Allow both negation and complement as subexpressions of both bitwise
and numeric operators.
- Remove parsing support for postincrement and postdecrement.
- Add parsing support for `as` operator.
- Use the same ambient precedence for types and non-type expressions.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
Refactor type canonicalization so that we can reuse the same code for
building a `T*` expression and for forming the type of an `&x`
expression.
Add basic computation of expression category in order to check that we
only take the address of durable reference expressions. This is
currently computed on demand rather than being tracked as part of the
semantics node, but in most cases can be determined by looking at only a
single expression, so caching it in the node doesn't seem worthwhile
yet. This decision should be revisited if we start doing more complex
category calculations.
Also add trivial lowering support, but it doesn't work properly yet
because lowering doesn't yet take the expression category into account.
Allow interleaving of STDOUT and STDERR check lines. Put STDOUT lines
after the line they're attached to, and STDERR lines before. If no
STDOUT check line is attached to any line, then put them all at the end
of the file instead.
This is intended to better handle the case where stdout contains
unreplaced mentions of line numbers, and also reflects that stdout is
typically a consequence of the test rather than commentary on it, so
placing it after the test seems likely to read better.
Semantic handling for use of `T*` and `const T` as types.
There's no way to form values of these types yet, and no conversions for
them are supported.
Factor out the common code to canonicalize types using a folding set,
and switch to using the same folding set for all kinds of type by adding
the kind as part of the folding set key.
Improve type printing to not include the `as type` portion when the type
is printed in a context within another type where a conversion to `type`
is implied, as in `{}*` and pre-existing cases like `({}, {}) as type`
(which we used to print as `({} as type, {} as type}) as type`.
I've migrated the toolchain autoupdate scripts here, I just need a
little more time to do the explorer side (which I need to check
performance, that may require multithreading as we do in the current
script). However, this felt substantial enough to share and it means I
can handle autoupdate in more of the toolchain, including preparatory
work for autoupdate on multi-file tests.
Once explorer is done I'll remove the old script.
For `Assign` and `ReturnExpression`, this field wasn't used for
anything. For `StructTypeField`, we stored the type of the field here,
and now store it as an argument of the node instead.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
This is a simplification of the construction, although somewhat limiting
(it means that the caller can't register the same file multiple times,
though I stopped doing that anyways since it was causing confusion).
What this more importantly _allows_ is logic on the FileTestBase child
itself that's not test-specific -- in particular, autoupdate
functionality which wouldn't use RUN_ALL_TESTS.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
This is sufficient to convert remaining toolchain tests to file_test. %s
and %t are currently used. While #2978 might use %T with lit, I think
that's resolving a lit-specific issue that's not necessary when
TEST_TMPDIR is readily available for any necessary operations (i.e.,
setting the working directory). With ARGS, I think it's feasible to
switch to file_test without %T.
Also adds documentation to file_test_base.h, which was starting to feel
like a significant gap.
This is not yet handled by autoupdate, but I'm eyeing that next.
Also switch from modeling type values as `i1` to modeling them as an
empty struct. We don't need any runtime representation for types, as
there are no runtime operations on them, so an empty struct seems like a
good representation.
Putting fuzzer files under //testing to emphasize the testonly aspect
(consolidates bazel and common subdirectories). The attributes on
explorer_fuzzer are also a little skewed from what's desirable; it's
been working okay, but this should still be a refinement.
Right now we expect crashes on invalid parses, we just don't try to
handle it in general even though the long-term intent is we should
handle semantics for bad parses. However, in theory, we should be
correctly handling code that parses as valid and that's probably more
interesting to fix bugs for. So this starts trying to fuzz that space of
valid parses.
Fuzzer corpus is based on explorer tests, with one merge run.
This also makes the filename a reference to the buffer since the line
seems better to have as a reference (versus copying a string per error).
Most tests now have different line deltas due to the extra output, but
the actual errors should overall stay the same.
Some of the error locations look like they could be improved, but this
change is only making it clear where they were before.
Handles tuples (including nested tuples) in the semantic phase of the
tool chain. Does not handle tuple element access yet.
---------
Co-authored-by: Farzana Ahmed Siddique <fasiddique@google.com>
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
This started with cleaning up the remaining Name/expression type punning
in the node stack, and grew. I'm factoring out a class because we've
previously expressed the desire to factor logic out of SemanticsContext
where possible, and this seemed like a reasonable cut.
NameExpression as the first node as a QualifiedExpression allows the
qualifier handling to consider Name in one less spot, an incremental
simplification. However, the additional complexity caused by this makes
me split ApplyNameQualifier/ApplyExpressionQualifier in order to avoid
repeat checks of the parse node's kind. The logic is still largely
shared, thus a couple helper functions. I think this is all fairly well
structured in the isolated class.
I can see that we may want to avoid passing SemanticsContext as an
argument in the future if it elides a step of lookup.
This adds a distinction between Unused and SoloParseNode, rather than
equating the two. This is intended to help identify nodes which are
getting pushed but maybe don't need to be.
Not totally done because I want to adjust declaration name handling due
to a quirk with how it mixes Name with Expression, but almost done. Once
that's done the type punning will be completely gone.
I think there's more we can do here, but this seemed like a good
checkpoint to make sure the path I'm going down is roughly what you
expected. There's one actual edit in if expression structure to match
the increased enforcement.
This handles namespacing of functions. Parsing and semantics are changed
significantly, while lowering works without changes. Variables can't be
namespaced yet because they're dealing with patterns, and I didn't dig
through that code.
Most of the logic is done through the new name declaration stack, which
is necessary because semantics isn't quite sure where the declaration
name ends. It'd be complex for parsing to send a signal about this,
probably involving node variants and rewrites of the tree, and this
solution seems to work well. Unfortunately this means a new stack, but
that may be inevitable due to the extra information needing to be
tracked.
Note this doesn't deal with scoped lookups of non-namespace things,
which we'll need for generics. That'll probably involve pushing resolved
scopes onto a stack (or maybe just setting a singleton value?) to affect
contextual name lookup. But, I think the basics are there to make it
work when we can test the behavior.
This renames "designator expression" to "qualified expression" and adds
"qualified declaration" in order to use terminology more consistent with
C++.
Namespaces will probably need to be considered for name mangling down
the line, but this still uses the basic name.
`semantics_handle.cpp` is a little on the large side, and is going to grow as we add new nodes. Some of the statement-specific parts have already been split into their own files. Split out the remaining such parts.
This PR renames parse nodes on a Name/NameExpression taxonomy. NameExpressions occur in a name context. The difference is that in non-expression contexts it's useful to return the identifier / string ID for adding to name lookup, whereas in expression contexts it's useful to return the resolved node ID for consistency with other expressions.
In the code, I do note SelfValueName is returned in the expression context: I'd expect this to change, as `self` in `[self: Self]` versus `self.Foo()` will probably be best handled similarly to the above. That means that, in the proposed taxonomy, both `SelfValueName` and `SelfValueNameExpression` will exist in order to assist semantics.
To contrast choices:
Original | Current | [zygoloid suggestion](https://discord.com/channels/655572317891461132/655578254970716160/1121581663399464970) | [This PR](https://discord.com/channels/655572317891461132/655578254970716160/1121814551789318215)
--- | --- | --- | ---
DeclaredName/DesignatedName | Identifier | NameComponent | Name
NameReference | NameReference | NameReference | NameExpression
SelfValueIdentifier | SelfValueIdentifier | SelfValueReference | SelfValueName
SelfTypeIdentifier | SelfTypeIdentiifer | SelfTypeReference | SelfTypeNameExpression
Add validation that every code block in a function is terminated by a sequence of terminating instructions, and that terminators don't appear anywhere else in code blocks.
This required tracking whether we're in a reachable code block. That's done on the fly when we create a new code block; the new `SemanticsNodeBlockId::Unreachable` is used to represent the case where we're not actually creating a code block because we're in unreachable code.
This is just a simplification: I think these different forms are getting in the way more than they're helping, particularly as I was looking into namespace functionality. The handling in semantics can be identical, providing a more uniform behavior.
This follows the same structure as `if` expressions, except that no
result value is needed.
Semantics IR building for code blocks is also added. Rather than popping
all the node stack entries we push for statements within a code block,
change statements and declarations to not push themselves onto the
stack. We're not notionally performing work recursively within prior
statements, and we don't need their value for anything, so it seems
cleaner to not push them. This also allows statements and declarations
to determine what syntactic context they're in by peeking at the top of
the stack, though that's not used in this patch.
Replacing direct raw_string_ostream uses. I figure the wrapper should be used more consistently.
There are still remaining raw_string_ostream uses that weren't compatible -- I'm continuing to look at those, but felt it was cleaner to have this on its own.
This is just a cleanup. Since we now have a testing directory, I think this is a better home for testonly libraries than //common. (I was thinking about this when I was considering adding more test_raw_ostream deps)
Add semantic analysis and semantics IR building for `if` expressions, and add the first parts of control flow handling to semantics IR. After discussion with @chandlerc, use [block arguments](https://en.wikipedia.org/wiki/Static_single-assignment_form#Block_arguments) to convey values from the two arms of the `if` to the result. For now, only a single block argument is supported, but we should revisit this as we explore more of the requirements of the Semantics IR form.
Functions can now contain multiple code blocks, so grab the entry block up-front instead of assuming the entry block will be at the top of the block stack when we reach the end of function emission.
Add trivial support for `bool` type literal, because without it we can't write testcases.
Now that the driver uses vfs, there's less reason for tests to do their own flow. Switch SemanticsIRTest to use the driver directly as an example simplification.
Richard SmithandChandler Carruth
Farzana Ahmed SiddiqueandFarzana Ahmed Siddique
Jon Ross-Perkins