Implements a backend targeting RV32GC and RV64GC, based on Linux standardizing around GC. The assembler is written to make it easy to disable usage of C, but because the sizes of some instruction sequences are compile-time constants, an additional build configuration would need to be defined to make use of it.
The assembler and disassembler cover every RV32/64GC instruction. The simulator covers all instructions except accessing CSRs and the floating point state accessible through such, include accrued exceptions and dynamic rounding mode.
Quirks:
- RISC-V is a compare-and-branch architecture, but some existing "architecture-independent" parts of the Dart compiler assume a condition code architecture. To avoid rewriting these parts, we use a peephole in the assembler to map to compare-and-branch. See Assembler::BranchIf. Luckily nothing depended on taking multiple branches on the same condition code set.
- There are no hardware overflow checks, so we must use Hacker's Delight style software checks. Often these are very cheap: if the sign of one operand is known, a single branch is needed.
- The ranges of RISC-V branches and jumps are such that we use 3 levels of generation for forward branches, instead of the 2 levels of near and far branches used on ARM[64]. Nearly all code is handled by the first two levels with 20-bits of range, with enormous regex matchers triggering the third level that uses aupic+jalr to get 32-bits of range.
- For PC-relative calls in AOT, we always generate auipc+jalr pairs with 32-bits of range, so we never generate trampolines.
- Only a subset of registers are available in some compressed instructions, so we assign the most popular uses to these registers. In particular, THR, TMP[2], CODE and PP. This has the effect of assigning CODE and PP to volatile registers in the C calling convention, whereas they are assigned preserved registers on the other architectures. As on ARM64, PP is untagged; this is so short indices can be accessed with a compressed instruction.
- There are no push or pop instructions, so combining pushes and pops is preferred so we can update SP once.
- The C calling convention has a strongly aligned stack, but unlike on ARM64 we don't need to use an alternate stack pointer. The author ensured language was added to the RISC-V psABI making the OS responsible for realigning the stack pointer for signal handlers, allowing Dart to leave the stack pointer misaligned from the C calling convention's point of view until a foreign call.
- We don't bother with the link register tracking done on ARM[64]. Instead we make use of an alternate link register to avoid inline spilling in the write barrier.
Unimplemented:
- non-trivial FFI cases
- Compressed pointers - No intention to implement.
- Unboxed SIMD - We might make use of the V extension registers when the V extension is ratified.
- BigInt intrinsics
TEST=existing tests for IL level, new tests for assembler/disassembler/simulator
Bug: https://github.com/dart-lang/sdk/issues/38587
Bug: https://github.com/dart-lang/sdk/issues/48164
Change-Id: I991d1df4be5bf55efec5371b767b332d37dfa3e0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/217289
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Slava Egorov <vegorov@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
* Add fallbacks to package smith to match the build recipes.
Cq-Include-Trybots: luci.dart.try:dart-sdk-linux-try,dart-sdk-mac-arm64-try,dart-sdk-mac-try,dart-sdk-win-try
Change-Id: I2d9da9e02119227bf59d4c200c886df4afc87487
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/202963
Commit-Queue: Alexander Thomas <athom@google.com>
Reviewed-by: William Hesse <whesse@google.com>
Reduce the suites run by AOT ASAN/MSAN to "vm" and "standalone"; the full set of suites takes longer than the bot timeout.
Change-Id: I29cb0cfc19d429d63229f2123fe7f6ddfad93cd0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/142566
Reviewed-by: Alexander Markov <alexmarkov@google.com>
Original change is in Patchset 1. I erroneously assumed DART_PRECOMPILER
was only used AOT compilation (it is also used for JIT snapshots).
Change-Id: I77f6c463db7f2b482c9b098f353dc28f0676ea0d
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/135900
Reviewed-by: Martin Kustermann <kustermann@google.com>
Commit-Queue: Samir Jindel <sjindel@google.com>
- Better name than "optedIn".
- Actually hook up the command-line option to the configuration.
- Add tests, which would have caught the previous mistake.
- Don't allow comma-separated values for "--progress" and "--nnbd".
- Remove unused dead "--strong" option.
Change-Id: I57d7cb0d81af50d662dcf3f7f4c9ca1f2b102f2f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/116544
Commit-Queue: Bob Nystrom <rnystrom@google.com>
Auto-Submit: Bob Nystrom <rnystrom@google.com>
Reviewed-by: Mayank Patke <fishythefish@google.com>
Towards #37318
- appJit has been replaced by appJitk and is no longer.
- precompiled has been replaced by dartkp and is no longer used.
- For the precompiled runtime, default to dartkp.
- Remove status file references to these compiler options and normalize
status files.
Change-Id: I48728db13dc84737092a92314e2f474a9309f4d9
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/106942
Reviewed-by: Alexander Thomas <athom@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>
This adds support for BabelJS to test.py's dart2js compiler
configuration. When --babel is specified directly or through a named
configuration, test.py will run an additional step after dart2js that
post-processes the javascript output by running it through BabelJS with
the specified Babel configuration. BabelJS is added to the DEPS in its
standalone form. d8 is used to run BabelJS standalone to avoid adding
a dependency on NodeJS. d8 can only write to stdout but not to files or
stderr, which makes it necessary to change the test_runner to handle
commands that expect their output to be piped to a file.
Changes:
* Add --babel option to test.py.
* Add babel option to pkg/smith.
* Switch IE11 builder to use babel transformation.
* Fix option list comparison bugs in pkg/smith.
* Change dart2js compiler configuration to generate files using the
test name rather than just "out.js" (update test that relied on this).
* Remove runtime_configuration dependency on test_suite.
* Remove obsolete blocks adding --preview-dart-2 dart2js arguments.
* Make dart2js' compiler configuration more like DDC's.
* Remove createCommand method that is no longer used.
* Remove support for "OtherResources" which was only used for
dart:isolate tests on dart2js and DDC.
* Skip co19_2 tests that are slow to transform with babel.
* Simplify the timeout handling in the test runner with Future.timeout.
Change-Id: I32e4917b2a57ecbe684538e40d744f0101c552a0
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/90402
Commit-Queue: Alexander Thomas <athom@google.com>
Reviewed-by: Sigmund Cherem <sigmund@google.com>
Makes the --keep-generated-files flag an option for the test.py command
only, not part of a named configuration passed in with the -n flag
and defined in tools/bots/test_matrix.json.
Change-Id: If67c2848cf6fc15e4cb7167ce23eeb3eb9bd1684
Reviewed-on: https://dart-review.googlesource.com/c/85705
Commit-Queue: Martin Kustermann <kustermann@google.com>
Reviewed-by: William Hesse <whesse@google.com>
This CL just adds the compiler=compareAnalyzerCfe option to the test
framework, and updates the status files so that no language_2 failures
are expected when this "compiler" is used. A placeholder executable
has been added to sdk/bin, but it is not wired up yet--that will be
done in a future CL.
In a future CL I will wire up the placeholder executable to the code
in pkg/analyzer_fe_comparison, and fill in the methods in
CompareAnalyzerCfeCommandOutput to process the output accordingly.
Change-Id: I27439de4ac609cb8b003f157a0ff88d181bfbcae
Reviewed-on: https://dart-review.googlesource.com/73561
Commit-Queue: Paul Berry <paulberry@google.com>
Reviewed-by: Bob Nystrom <rnystrom@google.com>
* Update named configs for unit tests to Dart 2.
* Bump json_rpc_2 in front_end package.
* Use named configurations in unit tests.
* Fix typing issues.
Change-Id: Id3b393a0d2abe92c8eaec10fa8057fb35d18a4c6
Reviewed-on: https://dart-review.googlesource.com/67341
Reviewed-by: Jens Johansen <jensj@google.com>
Alexander Thomas