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.
Add partial support for initializing expressions for variable declaration. This is based on https://github.com/carbon-language/carbon-lang/pull/2006, which introduces expression categories, and how it is possible to convert to/from those different categories.
## Functional changes
* Initializing expressions initialize directly the provided storage when used to initialize a variable.
* Allows initializing expressions to avoid a copy when using `[var|let] name: type = call_expression(...)` by initializing `name` in-place.
* Support `returned var: ...` and `return <expr>`
* Support nested initializing expressions
## Main implementation changes
* Updated PatternMatch logic to handle expression categories
* Updated `VariableDefinition` interpreter statement to allocate and pass a location to initializing expressions
* Update statement actions to allow passing an allocation, used by return expr or returned var
* Modified the RuntimeScope API to be one step closer to the memory model we want to have
* Remove `GetAllocationId` and older `Bind` which don't apply
* New set of tests to highlight those different situations
* Added a new intrinsic to print the allocation stack (and make sure we behave correctly, beyond visible side effects)
## Next work
* Dedicated `Action` to retrieve expression category information in the interpreter (https://github.com/carbon-language/carbon-lang/pull/2927)
* Avoid copies when initializing value expression from reference expression and prevent mutations for the duration of the "pinning" (https://github.com/carbon-language/carbon-lang/pull/2927)
* Avoid unnecessary copies from value expression to value expression, after ensuring that even value expression temporaries are registered for destruction.
* Avoid unnecessary copies when binding function arguments
The intent of this change is that instead of paths looking like `explorer/testdata/foo/bar.carbon` (repo-relative), they're now just `bar.carbon` (local). The consequence is that paths should be a bit more durable in various environments, and just paths should be shorter and easier to read.
The explorer's prelude is an exception to this since it comes from data, rather than being the test target. Due to the change in approaches, it needs the regex again.
Uses #2829
Isolating test execution time (no build time included):
- Linux, `lit` test-per-file: Elapsed time: 28.214s, Critical Path: 13.97s
- Linux, `cc_test`-per-file: Elapsed time: 11.534s, Critical Path: 6.05s
- Linux, merged `cc_test` with 50 shards: Elapsed time: 11.677s, Critical Path: 11.17s
- Mac, `lit` test-per-file: Elapsed time: 295.686s, Critical Path: 20.00s
- Mac, `cc_test`-per-file: Elapsed time: 55.788s, Critical Path: 3.81s
- Mac, merged `cc_test` with 50 shards: Elapsed time: 16.269s, Critical Path: 7.54s
In GH actions:
- [Before](https://github.com/carbon-language/carbon-lang/actions/runs/4866602695/jobs/8678306144?pr=2799):
- test / test (ubuntu-22.04, fastbuild) (pull_request_target) Successful in 20m
- test / test (ubuntu-22.04, opt) (pull_request_target) Successful in 15m
- test / test (macos-12, fastbuild) (pull_request_target) Successful in 36m
- test / test (macos-12, opt) (pull_request_target) Successful in 21m
- [After](https://github.com/carbon-language/carbon-lang/actions/runs/4875154751/jobs/8697004066?pr=2811):
- test / test (ubuntu-22.04, fastbuild) (pull_request_target) Successful in 10m
- test / test (ubuntu-22.04, opt) (pull_request_target) Successful in 9m
- test / test (macos-12, fastbuild) (pull_request_target) Successful in 12m
- test / test (macos-12, opt) (pull_request_target) Successful in 9m
I'm still leaving a handful of `lit` tests to test end-to-end binary execution. This is why testdata directories are split (`lit` tests next to the `explorer` binary, the `cc_test`s next to `ParseAndExecute`).
This is adding more validation of intrinsics. It addresses a bug in rand where CHECK-fails would occur for bad range inputs, instead of a runtime error. I'm also addressing what I think was an int32 range issue in the handling by running the generator with int64.
Rename value categories to expression categories based on [Discord discussion](https://discord.com/channels/655572317891461132/753021843459538996/1092924035517665332) regarding naming and behavior.
>* let expression -> value expression
>* var expression -> reference expression
>* located expression -> initializing expression
>So:
>- "value expressions" produce values (with no associated location). "reference expressions" produce a location of an existing value. "initializing expressions" take a location and initialize it.
>- A let binding is initialized by a value expression, because lets represent values (with category conversions performed as needed, but if a conversion is performed from a different category of expression, the value of the object is pinned for the lifetime of the let).
>- A var binding is initialized by an initializing expression, without performing a copy (with category conversions performed as needed, calling a copy constructor if the initializer is a different expression category).
>- The & operator requires a reference expression, and it's an error to give it other kinds.
>- The left-hand side of . requires a value expression when calling a function with a non-addr receiver, and requires a reference expression when calling a function with an addr receiver (it's an error to give it a value expression, and for an initializing expression, a temporary is materialized).
Changes
* Rename "value category" to "expression category"
* Rename Var and Let value categories to Value, Reference, and Initializing expression
* Rename `lvalue` to `location` (most of the time)
These functions are dangerous, as they check whether conversions are possible without actually performing the conversions. In each case where they were used, explorer would crash in some cases if a user-defined conversion is required.
This change moves us more towards implicit conversions being handled by a regular function call on an interface and away from them being magical builtins. Unfortunately, this exposes a pre-existing bug that a call of the form `x.(ImplicitAs(T).Convert)()` compiles even if `x` only has an explicit conversion to `T`. That's worked around here for now, but will need a proper fix later.
Adds a simple script to merge stdout/stderr and put on labels. This is hidden to the RUN line using lit.cfg.py.
This is my solution to addressing how errors printed by the toolchain break sorting of stdout output; just put stdout first. We could also have toggles for interleaving output or such, which might help test whether we do it properly.
This also moves some previous-distributed replacement logic into lit_autoupdate_base.py: I think having that adjacent to lit.cfg.py is probably the better choice, and it reduces duplication in toolchain scripts. It happens here because I need to change the resulting commands to include the merge.
On #2224 @zygoloid pointed out we needed --implicit-check-not to ensure we were correctly matching output. This is the standard way we're writing explorer tests, so I was looking at unifying our lit approaches.
This is one take on it, making more use of substitutions to bring various testing into alignment, as well as symlinks to avoid config skew (maybe I'll eventually figure out a better solution than symlinks).
Makes a couple small fixes in explorer to remove end-of-line whitespace on output.
* initial implementation of new and delete
* remove requirement for empty heap from trace.carbon
* more tests
* fixed substitution for generic function types
Use FileCheck's `[[@LINE+n]]` mechanism to refer to the next line.
This is made awkward by a couple of things:
* We want to keep the `CHECK` lines in the original order.
* Errors are sometimes more than one line long.
The approach we use is to interleave the original lines and the check lines, putting each check line as early as possible subject to two rules:
1) Check lines never precede the 'AUTOUPDATE' line
2) Except when required by rule (1), a check line that refers to a source line by line number is never placed earlier than a source line that precedes that source line.
The actual `[[@LINE+n]]` annotations are created in a second pass after we've interleaved the lines so that we can work out the correct offsets.
Co-authored-by: Jon Meow <jperkins@google.com>
Richard Smith
Adrien Leravat
josh11b
Jon Ross-Perkins
cui fliter
Jeremy G. Siek