Generate declarations of specific functions on demand. Definitions are
not emitted yet, and I'm using a temporary, known-broken scheme for name
mangling.
Here I'm trying to add some simple formatting based on the token kind,
aiming mainly to keep the implementation short for now.
This approach won't generalize to arbitrary structures (e.g., it doesn't
discern between braces for a function body and a struct literal). I
think we'll probably want to build a parse tree and associate parse
kinds with tokens in order to format, additionally doing something less
linear. But my essential goal at present is to just get a
proof-of-concept that the basics can yield something that looks okay.
This is improving the comment production to produce fewer distinct
comments.
At present, comment processing uses strict prefix matching. It either
expects `// ` (with a space) for valid comments, or just `//` (without a
space) for invalid comments that lacked the space.
As a consequence, the following would be three comments:
```
// Comment 1
//
//
// Comment 4
```
This is because a 3-character prefix is used for valid comments. The
prefix switches between lines 1 and 2, and again between lines 3 and 4,
each resulting in a separate comment.
For contrast, this is one comment because only a 2-character prefix is
used:
```
//Comment 1
//
//
//Comment 4
```
That's because all lines lack a suffix space.
Additionally, with SIMD 16-byte boundaries, further splits can occur if
processing needs to transition to non-SIMD.
Here, I'm trying to just address all of this by:
1. Stitching together adjacent comments. Since a lexed comment starts at
the `//` excluding the indent, the delta from the prior comment must be
precisely the indent.
2. Adding support for switching from SIMD to non-SIMD on file
boundaries.
I considered trying to have a separate `//\n` prefix for SIMD processing
of `// `, but I wasn't sure about the tradeoff of doing both at the same
time (in particular, it'd require constructing a string for the
different prefix), thus this stitch approach. This does mean multiple
passes will be required for a typical long comment structure using blank
comment lines to separate paragraphs (for performance reasons, I will
recommend engineers not write comm... nevermind).
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
Add a new `specific_function` instruction that represents a generic
function plus its deduced argument list as a callee in a function call.
The new instruction can only appear as the immediate operand of a call
instruction, so we give it a builtin placeholder type.
At the end of each file, require definitions for all specific functions
used in that file. Resolve the generic with the argument list to produce
those specific function definitions as needed, and diagnose if the
generic doesn't have a definition available.
A few tests are updated in cases where they declared and used generic
functions but didn't previously provide a function definition.
Note in particular that this fixes an issue where SharedValueStore had
been shared across files, when they should be per-file. This is only
visible when doing multiple compilations in a single test, which was
rare before.
This also moves these tests into the Testing namespace. My memory of the
various namespacing changes is that we'd generally agreed to have tests
in Testing so that we'd see SemIR:: and similar, same as we would in a
lot of the implementation.
In order to format comments, it's helpful if they're tracked. This
tracks them separately from tokens in order to avoid interfering with
parse; it'd be inconvenient if comment tokens could show up in arbitrary
locations, albeit possible to support.
This additionally extracts out the TokenIterator support into a template
in order to generally have it available for IndexBase types. I'm only
adding it for CommentInfo, not sure if we'll want it elsewhere, but this
structure still felt like a good fit.
The locations point to the first instruction in the generic that needed
the relevant constant value or type.
For now, this must makes the formatted SemIR a bit more useful, but in
the future it will also provide locations for diagnostics caused by
monomorphization failure.
Since formatting covers comments, and the CHECK lines are in comments,
it can create recursive behaviors. This introduces AUTOUPDATE-SPLIT as a
way of formally designating a split to exclusively be used for
autoupdate output.
This extracts out the SourceBuffer handling of `-` in order to trivially
share it.
Note this still has a number of TODOs, it's just setting up the
essential subcommand infrastructure, with some tests demonstrating that
it at least does something.
This should substantially reduce the total build size of `-c dbg`
builds, and especially improve cache hits during incremental
development. I'm seeing over 50% reduction total on Linux in just the
raw size of a complete debug build. Even on macOS where we can't use
split DWARF there are substantial reductions.
Note that LLDB and GDB want slightly different flags to have the best
experience with split debug information, and so the build and
documentation have been updated to enable LLDB's flags by default but
provide clear instructions for switching to GDB's flags, and they are
structured so that this can be done persistently for an individual
developer.
This adds deduction in all the cases where we can match the instruction
fields of the parameter against the corresponding instruction fields of
the argument. This handles all current type constants except for struct
types, for which we would want to match by field name.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Refactor the current function call deduction logic to make it reusable.
Call into it from `impl` deduction. Also build a generic region for the
definition portion of a generic `impl` and substitute into it before
accessing the witness in a specific `impl`.
This is enough to get simple uses of generic `impl`s to work. The main
blocker for more complex cases is that we have very little support for
non-trivial deduction, so while we can deduce `forall [T:! type] T as
I`, we can't deduce `forall [T:! type] C as I(T)` yet.
Instead of stringifying types in the caller in some cases, add new types
to represent:
- `InstIdAsType`: an `InstId` diagnostic argument that represents a type
expression that should be included in the diagnostic
- `InstIdAsTypeOfExpr`: an `InstId` diagnostic argument that represents
an expression whose type should be included in the diagnostic
For these cases, we can produce more user-friendly descriptions of a
type than we can with a canonicalized `TypeId`. Add comments to
discourage using `TypeId` diagnostic arguments when one of the above can
be used, and move over existing uses where it's straightforward to do
so.
Move type stringification code to its own files and out of `SemIR::File`
to make `File` smaller and to further discourage the direct use of the
stringification logic.
Also update type printing to include the `` ` `` delimiters surrounding
the type. The intent is that we will eventually want to include other
information when formatting a type, like Clang does when printing a
typedef (`'string' (aka 'std::basic_string<char>')`), and such
formatting requires that the diagnostic machinery produces the `` ` ``s
itself.
There are a couple of cases where we really want to format valid Carbon
type syntax directly into a diagnostic, rather than an `aka` or similar,
because the diagnostic text includes part of the type itself, for
example: ``"consider using `partial {0}`"``. For such cases, a `Raw`
form of the diagnostic argument types is added: `TypeIdAsRawType` and
`InstIdAsRawType`. In principle we could instead use ``"consider using
`partial {0:raw}`"``, but our diagnostic machinery isn't set up for
that.
---------
Co-authored-by: josh11b <15258583+josh11b@users.noreply.github.com>
Causes the default development (`fastbuild`) Bazel build and test to
both use ASan, minimal optimizations, and produce good backtraces with
source locations.
This also fixes all of the non-host configs that were deeply broken for
the latest releases of Bazel going back quite some time.
The intent of our our Bazel toolchain config was for a minimally
optimized, minimal debug info, and ASan + UBSan configuration to be the
`fastbuild`, or the default development build of the project. This
matches its inclusion of asserts, etc.
At some point quite some time ago, all of this stopped working. Bazel no
longer has a `nonhost` feature. This was disabled a long time ago,
briefly argued to be re-enabled, but has persistently been removed.
However, since then the host and non-host features have been separated
including the compilation mode, and so none of that is needed now.
Instead, we can use a much simpler and more principled approach to all
of the feature configuration now which this PR implements.
However, we added TCMalloc _after_ all of the ASan stuff became broken,
and so we never saw that it is fundamentally incompatible with ASan. So
this PR also reworks how TCMalloc is used to only apply to `-c opt`
builds on Linux, and it also explicitly disables it when using
`--config=asan`. I've not found a convenient way to tie the malloc
library choice to a toolchain feature in Bazel, so this relies on the
config being used rather than the feature in isolation.
Last but not least, with this change `fastbuild` creates substantially
larger output and so this change also passes several new flags to reduce
the size costs. One is a general improvement from outlining ASan
instrumentation. The others are in a special feature as they reduce the
error message quality for two of the more expensive UBSan checks in
favor of small generated code size. Keeping these last two separate
allows disabling this locally if needed to debug a failure.
When profiling, these jumped out as good inline candidates that happened
to be out-of-line, this just moves them inline so that they're
available. I think as much as 10% improvement in check-phase from this,
but I haven't run detailed before/after measurements as these changes
seemed minimally disruptive.
Also switched from `CHECK` to `DCHECK` in one place that seems
especially hot and where the check itself seems reasonable to only do in
debug builds. Left a comment since we rarely need to remove these any
more.
llvm::function_ref (like std::unique_ptr, for instance) already has a
null/empty state, so use that to avoid confusion/duplication of empty
states between optional and the nested function_refs.
This should free up quite a bit of space and even make our builds faster
by avoiding duplicating every output. The syntax for this flag is
counter intuitive, so I've left a comment explaining it.
With this, we now check:
* The left argument to `where` is a facet type
* The right argument of a rewrite (`=`) requirement converts to the type
of the left argument.
* The left argument of an `impls` requirement is a type and the right
argument is a facet type.
No checking is done for `==` constraints yet.
In addition, make the "is facet type" query into its own function and
fix some comments noticed as part of this change.
This change reveals that accessing the members of a facet, like `.Self`,
isn't doing the right thing, and will have to be fixed in a follow-on
PR. Some tests have been adjusted or disabled as a result.
---------
Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Updates `SemIR::Function::GetParamFromParamRefId` to return more
information in the form of a new `ParamInfo` struct. This struct has a
method for getting the `NameId` from the name binding instruction. The
callers previously got it from the `Param` instruction, but the plan is
for that instruction to no longer be associated with a name.
---------
Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Geoff Romer <gromer@google.com>
Not sure about error recovery options - can/should we drop the
definition as a means of recovery when building the SemIR? I guess
probably not, so I guess this change is about right.
Phrasing of the error message I'm certainly open to.
This makes the code more resilient to changes in the structure of
parameter insts, and could help avoid bugs by making the
ImportRefResolver's data structures the single source of truth.
According to
https://docs.carbon-lang.dev/docs/design/generics/details.html#adapting-types:
> You can add any declaration that you could add to a class except for
declarations that would change the representation of the type. This
means you can add methods, functions, interface implementations, and
aliases, but not fields, base classes, or virtual functions. The
specific implementations of virtual functions are part of the type
representation, and so no virtual functions may be overridden in an
adapter either.
So, let's check/reject that.
Checking at the end of the class ensures that no matter the order of
methods and adapt statements, the issue will still be correctly
diagnosed.
If the bucket is of size zero or one, which is expected to be the common
case, then store it directly. For the remaining cases, use a side table
of lookup buckets.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
Update impl handling to more closely match other kinds of declaration,
including support for declaring and defining gneeric `impl`s.
When of performing redeclaration lookup for impls by looking for the
self and constraint type, produce a list of impls rather than a single
impl because it's possible for there to be multiple impls with different
deduced parameters but the same self type and constraint. Following
#3763, only consider impls to be redeclarations if they're spelled the
same, not just if they have the same self and constraint types.
No support yet for impl selection to deduce the arguments of a generic
impl.
---------
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
This only sets the symbolizer for our more used targets; not sure if
there's a great way to set it everywhere (I suppose I could try wrapping
cc_binary etc rules if there's a strong preference).
There is a downside here, symbolizing a fastbuild crash seems to take
about 3s. Not sure if there's a good way to get a faster llvm-symbolizer
execution...?
I tried running with the new LLVM update without the
LLVM_SYMBOLIZER_PATH, and it looks like that's insufficient. With the
settings, I now get readable crashes:
```
#9 0x000055dc007d1724 void Carbon::Internal::CheckFail<Carbon::TemplateString<5>{"FATAL"}, Carbon::TemplateString<27>{"toolchain/driver/driver.cpp"}, 84, Carbon::TemplateString<0>{}, Carbon::TemplateString<3>{"err"}>() (/usr/local/google/home/jperkins/.cache/bazel/_bazel_jperkins/85deb7d9d96f7e0e80b42618a55969d7/sandbox/linux-sandbox/9383/execroot/_main/bazel-out/k8-fastbuild/bin/toolchain/testing/file_test.runfiles/_main/toolchain/testing/file_test+0x2894724)
```
Note the LLVM update is for
https://github.com/llvm/llvm-project/pull/109021
`ToolContext` should be explicitly initialized.
`-c` can still require a valid, writable `-o` path.
---------
Co-authored-by: Chandler Carruth <chandlerc@gmail.com>
When an instruction makes an absolute reference to another instruction,
such as when `assoc_const` refers to the declaration of the associated
constant in an interface, substitution into that instruction should not
substitute into the referenced instruction.
Mark the corresponding `InstId` fields in the typed instructions as
being absolute by giving them a distinct ID type that `Subst` doesn't
substitute into. This formation of unnecessarily complicated SemIR that
could in some cases lead to a CHECK failure when printing formatted
SemIR because the same instruction ends up in multiple scopes.
One of the things that ClangRunnerTest is doing is capturing
stderr/stdout because clang prints to it directly. This adds support for
that to FileTest.
I'm renaming the current `capture_output` field to `dump_output` because
the name is ambiguous after this change, and the flag is already named
`--dump_output`. It's still not great, but at least it's more distinct.
Note ClangRunner still doesn't use the vfs; that still needs work. I'm
just moving the NoArgs test over as a trivial test of the functionality.
The check stage now produces SemIR instructions to represent a `where`
clause. It still does not check types.
---------
Co-authored-by: Josh L <josh11b@users.noreply.github.com>
Co-authored-by: Jon Ross-Perkins <jperkins@google.com>
We're trying to remain compatible with an environment where
`declare_symlink` is (apparently) disallowed.
`--allow_unresolved_symlinks=false` will prevent regressions.
josh11bandJosh L
Richard Smith
Jon Ross-Perkins
Céline Dedaj
David Blaikie
Geoff Romer